U.S. patent application number 12/313342 was filed with the patent office on 2010-02-18 for methods for treating immune disorders associated with graft transplantation with soluble ctla4 mutant molecules.
This patent application is currently assigned to Bristol-Myers Squibb Company. Invention is credited to David Hagerty, James Rusnak.
Application Number | 20100041602 12/313342 |
Document ID | / |
Family ID | 36694299 |
Filed Date | 2010-02-18 |
United States Patent
Application |
20100041602 |
Kind Code |
A1 |
Hagerty; David ; et
al. |
February 18, 2010 |
Methods for treating immune disorders associated with graft
transplantation with soluble CTLA4 mutant molecules
Abstract
The present invention provides use of soluble CTLA4 mutant
molecules which bind with greater avidity to the CD80 and/or CD86
antigen than wild type CTLA4 or non-mutated CTLA4Ig in the
treatment of immune disorders associated with graft
transplantation.
Inventors: |
Hagerty; David; (Cardiff by
the Sea, CA) ; Rusnak; James; (Newtown, PA) |
Correspondence
Address: |
LOUIS J. WILLE;BRISTOL-MYERS SQUIBB COMPANY
PATENT DEPARTMENT, P O BOX 4000
PRINCETON
NJ
08543-4000
US
|
Assignee: |
Bristol-Myers Squibb
Company
|
Family ID: |
36694299 |
Appl. No.: |
12/313342 |
Filed: |
November 19, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11399666 |
Apr 6, 2006 |
7482327 |
|
|
12313342 |
|
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|
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60668774 |
Apr 6, 2005 |
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Current U.S.
Class: |
514/1.1 |
Current CPC
Class: |
A61K 9/0019 20130101;
A61K 38/1774 20130101; A61P 37/00 20180101; A61K 31/436 20130101;
A61P 37/06 20180101; A61K 31/5377 20130101; A61K 39/395 20130101;
A61K 31/573 20130101; A61P 25/28 20180101; A61P 37/02 20180101;
C07K 2319/30 20130101; A61K 38/1774 20130101; A61K 2300/00
20130101; A61K 31/436 20130101; A61K 2300/00 20130101; A61K 31/5377
20130101; A61K 2300/00 20130101; A61K 31/573 20130101; A61K 2300/00
20130101; A61K 39/395 20130101; A61K 2300/00 20130101 |
Class at
Publication: |
514/12 |
International
Class: |
A61K 38/16 20060101
A61K038/16; A61P 37/06 20060101 A61P037/06 |
Claims
1. A method for treating an immune disorder associated with graft
transplantation in subjects that have received an alternate
immunosuppressive therapy post transplantation comprising
administering to a subject an effective dose of a CTLA4 mutant
molecule comprising an extracellular domain of CTLA4 as shown in
SEQ ID NO:8 beginning with alanine at position 26 or methionine at
position 27 and ending with aspartic acid at position 150, or a
portion thereof, wherein in the extracellular domain or portion
thereof an alanine at position 55 is substituted with a tyrosine,
and a leucine at position 130 is substituted with a glutamic acid
and wherein the administration regimen comprises a conversion from
the alternate immunosuppressive therapy to the CTLA4 mutant
molecule, wherein the alternate immunosuppressive therapy is
decreased over an appropriate period of time and the CTLA4 mutant
molecule is administered more frequently than monthly.
2. A method for treating an immune disorder associated with graft
transplantation in subjects that have received an alternate
immunosuppressive therapy post transplantation comprising
administering to a subject an effective dose of a CTLA4 mutant
molecule comprising: (a) an amino acid sequence beginning with
methionine at position 27 and ending with aspartic acid at position
150 of SEQ ID NO:4, or (b) an amino acid sequence beginning with
alanine at position 26 and ending with aspartic acid at position
150 of SEQ ID NO:4 and wherein the administration regimen comprises
a conversion from the alternate immunosuppressive therapy to the
CTLA4 mutant molecule, wherein the alternate immunosuppressive
therapy is decreased over an appropriate period of time and the
CTLA4 mutant molecule is administered more frequently than
monthly.
3. The method according to claim 1 or 2 wherein the CTLA4 mutant
molecule is administered every two weeks during the conversion
period of the alternate immunosuppressive therapy.
4. The method according to claims 1 or 2 wherein the administration
regimen further comprises a maintenance phase regimen wherein the
maintenance phase regimen begins after the alternative
immunosuppressive therapy has been totally removed and wherein
administration of CTLA4 mutant molecule is not more frequent than
monthly.
5. The method according to claim 3 wherein the effective dose of
CTLA4 mutant molecule during the conversion is about 5 mg/kg weight
of the subject.
6. The method according to claim 4 wherein the effective dose of
CTLA4 mutant molecule during the maintenance phase is about 5 mg/kg
weight of the subject.
7. The method according to claim 1 or 2 wherein the immune
disorders associated with graft transplantation comprises solid
organ, tissue and/or cell transplant rejection.
8. The method according to claim 7 wherein the immune disorders
associated with graft transplantation comprises kidney or liver
transplant rejection.
9. The method according to claim 1 or 2 wherein the CTLA4 mutant
molecules further comprise an amino acid sequence which alters the
solubility, affinity and/or valency of the soluble CTLA4 mutant
molecule.
10. The method according to claim 9, wherein the amino acid
sequence which alters the solubility, affinity and/or valency
comprises an immunoglobulin moiety.
11. The method according to claim 10, wherein the immunoglobulin
moiety is an immunoglobulin constant region or portion thereof.
12. The method according to claim 11, wherein the immunoglobulin
constant region or portion thereof is mutated to reduce effector
function.
13. The method according to claim 11 wherein the immunoglobulin
constant region or portion thereof comprises a hinge, CH2 and CH3
regions of a human or monkey immunoglobulin molecule.
14. The method according to claim 12 wherein the immunoglobulin
constant region or portion thereof comprises a hinge, CH2 and CH3
regions of a human or monkey immunoglobulin molecule.
15. The method according to claim 10, wherein the immunoglobulin
comprises an amino acid sequence which begins with glutamic acid at
position +152 and ends with lysine at position +383, as shown in
SEQ ID NO:4.
16. The method according to claims 1 or 2 further comprising a
junction amino acid residue and an immunoglobulin, where the
junction amino acid residue is located between the amino acid
sequence which ends with aspartic acid at position +150 and the
immunoglobulin.
17. The method according to claim 1 or 2 wherein said CTLA4 mutant
molecule is co-administered with at least one of the agents
selected from the group consisting of basiliximab, daclizumab,
anti-thymocyte globulin, calcineurin inhibitors, cyclosporine,
tacrolimus, mycophenolate mofetil, mycophenolic acid, rapamycin,
azathioprine, muromonab, rituximab, sirolmus, everolimus, FTY720,
FK778, Jak-3, centican, corticosteroids, betamethasone, budesonide,
cortisol, cortisone, dexamethasone, hydrocritisone,
methylprednisolone, prednisolone, prednisone and triamcinolone.
18. A method according to claim 1 or 2 wherein development and/or
progression of an outcome selected from the group consisting of
CAN, hyperlipidemia, hypertension, diabetes, hirsuitism, alopecia,
gingival hyperplasia, tremor, neurotoxicity and bone loss is
reduced.
19. The method according to claim 1 or 2 further comprising a
target trough serum concentration of the CTLA4 mutant molecule
between about 3 .mu.g/ml and about 30 .mu.g/ml.
20. A method for treating an immune disorder associated with graft
transplantation in subjects that have received an alternate
immunosuppressive therapy post transplantation comprising
administering to a subject an effective dose of a CTLA4 mutant
molecule comprising: (a) an amino acid sequence beginning with
methionine at position 27 and ending with lysine at position +357
or glycine at position +356 of FIG. 7, or (b) an amino acid
sequence beginning with alanine at position 26 and ending with
lysine at position +357 or glycine at position +356 of FIG. 7 and
wherein the administration regimen comprises a conversion from the
alternate immunosuppressive therapy to the CTLA4 mutant molecule,
wherein the alternate immunosuppressive therapy is decreased over
an appropriate period of time and the CTLA4 mutant molecule is
administered more frequently than monthly.
21. The method according to claim 1, 2 or 20 wherein the CTLA4
mutant molecule is co-administered concomitantly or sequentially
with agents comprising basiliximab and MMF.
22. The method according to claim 1, 2 or 20 wherein the CTLA4
mutant molecule is co-administered concomitantly or sequentially
with agents comprising daclizumab and siroliums.
23. The method according to claim 1, 2 or 20 wherein renal function
of the transplanted subject is improved.
24. The method according to claim 28 wherein renal function is
measured by glomerular filtration rate (GFR).
Description
RELATED APPLICATION
[0001] This application is a continuation of U.S. application Ser.
No. 11/399,666, filed on Apr. 6, 2006, now allowed, which claims
priority of U.S. provisional Application No. 60/668,774, filed Apr.
6, 2005, the contents of both are herein incorporated by
reference.
[0002] Throughout this application various publications are
referenced. The disclosures of these publications in their
entireties are hereby incorporated by reference into this
application in order to more fully describe the state of the art to
which this invention pertains.
FIELD OF THE INVENTION
[0003] The present invention relates to the use of soluble CTLA4
mutant molecules, with increased binding avidity to CD80 (B7-1) and
CD86 (B7-2) compared with wild type CTLA4, in the treatment of
immune disorders associated with graft transplantation.
BACKGROUND OF THE INVENTION
[0004] Given the central role of T-cells in transplant rejection, a
common goal among current immunosuppressive therapies is to block
T-cell activation and function (Sayegh M H, Turka L A. The role of
T-cell costimulatory activation pathways in transplant rejection. N
Engl J Med 1998; 338(25):1813-21). T-cells require both an
antigen-specific (Signal 1) and co-stimulatory signal (Signal 2)
for full activation (Lenschow D J, Walunas T L, Bluestone J A.
CD28/B7 system of T cell costimulation. Annu Rev Immunol 1996;
14:233-58). One of the best-characterized co-stimulatory pathways
involves the CD28-CD80/86 (B7-1/2) interaction (Linsley P S,
Ledbetter J A. The role of the CD28 receptor during T cell
responses to antigen. Annu Rev Immunol 1993; 11:191-212). Cytotoxic
T-lymphocyte antigen 4 (CTLA4) binds to CD80/86 with higher avidity
than CD28, and is transiently expressed on T-cells following their
activation, where it interrupts the interaction between CD28 and
CD80/86 (Oosterwegel M A, Greenwald R J, Mandelbrot D A, Lorsbach R
B, Sharpe A H. CTLA-4 and T cell activation. Curr Opin Immunol
1999; 11(3):294-300.). This creates a negative feedback signal for
T-cell activation.
[0005] Intervention in this pathway has been previously pursued
with CTLA4Ig. CTLA4Ig has been successfully used as a strategy to
treat T-cell-mediated autoimmune disorders such as rheumatoid
arthritis (Kremer J M, Westhovens R, Leon M, et al. Treatment of
rheumatoid arthritis by selective inhibition of T-cell activation
with fusion protein CTLA4Ig. N Engl J Med 2003; 349(20):1907-15)
and psoriasis (Abrams J R, Lebwohl M G, Guzzo C A, et al.
CTLA4Ig-mediated blockade of T-cell costimulation in patients with
psoriasis vulgaris. J Clin Invest 1999; 103(9):1243-52).
[0006] LEA29Y has been studied in non-human primate transplant
models alone and in combination with other immunosuppressive
agents. Christian Larsen et al (C. Larsen, T. Pearson, A. Adams, P.
Tso, N. Shirasugi, E. Strobert, D. Anderson, S. Cowan, K. Price, J.
Naemura, J. Emswiler, J. Greene, L. A. Turk, J. Bajorath, R.
Townsend, D. Hagerty, P. Linsley and R. Peach; Rational Development
of LEA29Y (belatacept), a High-Affinity Variant of CTLA4-Ig with
Potent Immunosuppressive Properties; American Journal of
Transplantation; Vol. 5, Issue 3, March 2005, p. 443) have shown
the enhanced immunosuppressive activity of LEA29Y when compared to
CTLA4-Ig in a non-human primate model utilized to study renal
allograft rejection. LEA29Y was administered intra-operatively (10
mg/kg intravenously), on day 4 (15 mg/kg) and on post-operative
days 14, 28, 42, 56 and 70 (20 mg/kg intravenously). CTLA4Ig (16
mg/kg) was administered intra-operatively and on post-operative
days 4, 8, 11 and 16. The treatment regimen also included MMF (15
mg/kg bid s.c. on days 0-14, qd on days 15-180), methylprednisolone
(subcutaneouse injection according to the following schedule, day
0: 20 mg, day 1: 16 mg, day 3: 8 mg, day 4: 4 mg, day 5-14: 3 mg,
day 15-180: 1 mg) and basiliximab (0.3 gm/kg i.v. on day 0 and 4).
Survival of renal allograft recipients treated with LEA29Y was
clearly superior to that of a group treated with CTLA4-Ig despite
comparable serum concentrations. Control recipients treated with
albumin showed a similar median survival time to the group treated
with CTLA4-Ig. However, despite ongoing treatment with LEA29Y, all
recipients experienced a significant decline in renal function
(rise in serum creatinine).
[0007] Andrew Adams et al (A. Adams, N. Shirasugi, T. Jones, M.
Durham, E. Strobert, S. Cowan, P. Rees, R. Hendrix, K. Price, N.
Kenyon, D, Hagerty, R. Townsend, D. Hollenbaugh, T. Pearson and C.
Larsen; Development of a Chimeric Anti-CD40 Monoclonal Antibody
That Synergizes with LEA29Y to Prolong Islet Allograft Survival;
The Journal of Immunology; January 2005; 174; p. 542) have shown
that the combination of LEA29Y and Chi220 (a chimeric anti-human
CD40 mab) act synergistically in a non-human primate model of
pancreatic islet transplantation to prolong allograft survival.
LEA29Y was administered intravenously intra-operatively (20 mg/kg);
on postoperative days 4, 7 and 14; then every 2 weeks until day
100. Additional doses (20 mg/kg) were administered monthly through
6 months. Four protocols were tested: 1) LEA29Y alone, 2) Chi220
(anti-CD40), 3) LEA29Y combined with Chi220, and 4) LEA29Y combined
with anti-CD20.
[0008] Andrew Adams et al (A. Adams, N. Shirasugi, M. Durham, E.
Strobert, D. Anderson, P. Rees, S. Cowan, H. Xu, Y. Blinder, M.
Cheung, D. Hollenbaugh, N. Kenyon, T. Pearson and C. Larsen;
Calcineurin Inhibitor-Free CD28 Blockade-Based Protocol Protects
Allogeneic Islets in Nonhuman Primates; Diabetes, Vol. 51(2),
February 2002, p. 265) have shown that the combination of LEA29Y,
rapamycin, and anti-IL-2R mAb significantly prolonged islet
allograft survival. in a non-human primate model of pancreatic
islet transplantation. LEA29Y was administered intravenously
intra-operatively (10 mg/kg) and on postoperative day 4 (15 mg/kg).
Additional does of 20 mg/kg were given on postoperative day 14 and
every 2 weeks until postoperative day 154.
[0009] During 2003 more than 25,000 organs were transplanted in the
US. Kidney transplantation represented approximately 60% of the
solid organ transplants followed by liver transplants at 21%, heart
at 8%, lung at 4% and the remaining 7% represented other organ
transplants such as pancreas and intestine. (OPTN/SRTR Annual
Report 2004 at www.optn.org)
[0010] Renal transplantation is the most effective treatment for
end-stage renal disease. It provides improved survival and quality
of life (QoL). Maintenance of a functioning renal transplant
mandates lifelong immunosuppressive therapy to prevent immune
destruction of the graft. Current immunosuppressive regimens yield
1-year survival rates of 89% for cadaveric and 94% for living-donor
grafts. Over time, however, there is progressive loss of both
subjects and grafts. Five-year survival for cadaveric and
living-related donor renal transplants is 66% and 79%,
respectively. (United Network for Organ Sharing Renal Transplant
Registry 2003 at www.unos.org)
[0011] The most common causes of long-term subject and graft loss
are cardiovascular disease and chronic allograft nephropathy (CAN),
respectively. (L.C. Paul, Chronic allograft nephropathy--A model of
impaired repair rom injury? Nephrol Dial Transplant 2000;
15:149-151) Paradoxically, the principal therapies for renal
transplantation, the calcineurin inhibitors (CNIs), CsA and
tacrolimus, directly contribute to long-term allograft loss and
subject death, since they are inherently nephrotoxic, and also
cause or exacerbate cardiovascular risks, including hypertension,
hypercholesterolemia, and diabetes mellitus. Nonetheless, these
agents form the cornerstone of all conventional immunosuppressive
regimens for renal transplantation.
[0012] At present, there are no approved agents that can replace
CNIs as cornerstone maintenance immunosuppressant therapy in a
broad range of subjects. One agent, sirolimus (rapamycin,
Rapamune.RTM. from Wyeth/Ayerst), has been approved for use in a
CNI-sparing regimen. CNIs, however, must still be used with
sirolimus for at least 3 months post-transplantation. More
importantly, sirolimus has been approved as a CNI-sparing agent in
this setting only for subjects at low to moderate risk of graft
loss. Thus, for those at higher risk of graft loss, in whom
avoidance of the nephrotoxic effects of CNIs would be of greatest
benefit, there is no approved alternative to CNIs.
[0013] Therefore, there is an unmet medical need for
immunosuppressive agents that can provide acceptable control of the
alloimmune response comparable to standard of practice therapies
without toxicities that contribute to long-term subject death and
graft loss. Ideally, the agent would be useful not only in low-risk
subjects, but also in subjects at higher risk of graft loss.
SUMMARY OF INVENTION
[0014] The present invention provides methods for treating immune
disorders associated with graft transplantation by administering
CTLA4 mutant molecules which bind with greater avidity to the CD80
and/or CD86 antigen than wild type CTLA4 or non-mutated CTLA4Ig.
The CTLA4 molecules have a first amino acid sequence comprising the
extracellular domain of CTLA4, where certain amino acid residues
within the S25-R33 region and M97-G107 region are mutated. The
mutant molecules of the invention may also include a second amino
acid sequence which increases the solubility of the mutant
molecule.
[0015] One example of a CTLA4 mutant molecule is L104EA29YIg (FIG.
7, SEQ ID NOS: 3 and 4), as described herein. Another example of a
CTLA4 mutant molecule is L104EIg (FIG. 8, SEQ ID NOS: 5 and 6), as
described herein. L104EA29YIg and L104EIg bind CD80 and CD86 more
avidly than CTLA4Ig.
[0016] Administration of the CTLA4 mutant molecules of the
invention may be performed over various times. Typically,
administration regimens included an early phase, in which doses are
higher and the frequency of administration is increased during the
period of greatest immunologic risk, followed by a maintenance
phase. The early phase may range from the first 3 to 6 months
post-transplantation. The administration regimen during early phase
may vary depending on the status of the recipient/graft.
[0017] In one embodiment the present invention provides a method
for treating an immune disorder associated with graft
transplantation by administering to a subject an effective dose of
a CTLA4 mutant molecule with an extracellular domain of CTLA4 as
shown in SEQ ID NO:8 beginning with alanine at position 26 or
methionine at position 27 and ending with aspartic acid at position
150, or a portion thereof. Additionally, in the extracellular
domain or portion thereof an alanine at position 55 is substituted
with a tyrosine, and a leucine at position 130 is substituted with
a glutamic acid. Further the administration regimen comprises an
early phase regimen, wherein the early phase regimen may range from
the first 3 to 6 months post-transplantation and involves
administration that initially is more frequent than monthly.
[0018] In another embodiment the present invention provides a
method for treating an immune disorder associated with graft
transplantation by administering to a subject an effective dose of
a CTLA4 mutant molecule with an amino acid sequence beginning with
methionine at position 27 and ending with aspartic acid at position
150 of SEQ ID NO:4, or with an amino acid sequence beginning with
alanine at position 26 and ending with aspartic acid at position
150 of SEQ ID NO:4. Further the CTLA4 mutant molecule
administration regimen comprises an early phase regimen, wherein
the early phase regimen may range from the first 3 to 6 months
post-transplantation and involves administration that initially is
more frequent than monthly.
BRIEF DESCRIPTION OF THE FIGURES
[0019] FIG. 1 shows the equilibrium binding analysis of
L104EA29YIg, L104EIg, and wild-type CTLA4Ig to CD86Ig.
[0020] FIGS. 2A & 2B illustrate data from FACS assays showing
binding of L104EA29YIg, L104EIg, and CTLA4Ig to human CD80- or
CD86-transfected CHO cells as described in Example 2, infra.
[0021] FIGS. 3A & 3B depicts inhibition of proliferation of
CD80-positive and CD86-positive CHO cells as described in Example
2, infra.
[0022] FIGS. 4A & 4B shows that L104EA29YIg is more effective
than CTLA4Ig at inhibiting proliferation of primary and secondary
allostimulated T cells as described in Example 2, infra.
[0023] FIGS. 5A-C illustrate that L104EA29YIg is more effective
than CTLA4Ig at inhibiting IL-2 (FIG. 5A), IL-4 (FIG. 5B), and
.gamma.-interferon (FIG. 5C) cytokine production of allostimulated
human T cells as described in Example 2, infra.
[0024] FIG. 6 demonstrates that L104EA29YIg is more effective than
CTLA4Ig at inhibiting proliferation of phytohemaglutinin-(PHA)
stimulated monkey T cells as described in Example 2, infra.
[0025] FIG. 7 (SEQ ID NOS: 3 and 4) depicts a nucleotide and amino
acid sequence of a CTLA4 mutant molecule ("L104EA29YIg") comprising
a signal peptide; a mutated extracellular domain of CTLA4 starting
at methionine at position +1 and ending at aspartic acid at
position +124, or starting at alanine at position -1 and ending at
aspartic acid at position +124; and an Ig region as described in
Example 1, infra. SEQ ID NOS: 3 and 4 depict a nucleotide and amino
acid sequence, respectively, of a CTLA4 mutant molecule
("L104EA29YIg") comprising a signal peptide; a mutated
extracellular domain of CTLA4 starting at methionine at position
+27 and ending at aspartic acid at position +150, or starting at
alanine at position +26 and ending at aspartic acid at position
+150; and an Ig region.
[0026] FIG. 8 (SEQ ID NOS: 5 and 6) depicts a nucleotide and amino
acid sequence of a CTLA4 mutant molecule ("L104EIg") comprising a
signal peptide; a mutated extracellular domain of CTLA4 starting at
methionine at position +1 and ending at aspartic acid at position
+124, or starting at alanine at position -1 and ending at aspartic
acid at position +124; and an Ig region as described in Example 1,
infra. SEQ ID NOS: 5 and 6 depict a nucleotide and amino acid
sequence, respectively, of a CTLA4 mutant molecule ("L104EIg")
comprising a signal peptide; a mutated extracellular domain of
CTLA4 starting at methionine at position +27 and ending at aspartic
acid at position +150, or starting at alanine at position +26 and
ending at aspartic acid at position +150; and an Ig region.
[0027] FIG. 9 (SEQ ID NOS: 7 and 8) depicts a nucleotide and amino
acid sequence of a CTLA4Ig having a signal peptide; a wild type
amino acid sequence of the extracellular domain of CTLA4 starting
at methionine at position +1 to aspartic acid at position +124, or
starting at alanine at position -1 to aspartic acid at position
+124; and an Ig region. SEQ ID NOS: 7 and 8 depict a nucleotide and
amino acid sequence, respectively, of a CTLA4Ig comprising a signal
peptide; a wild type amino acid sequence of the extracellular
domain CTLA4 starting at methionine at position +27 and ending at
aspartic acid at position +150, or starting at alanine at position
+26 and ending at aspartic acid at position +150; and an Ig
region.
[0028] FIGS. 10A-C are an SDS gel (FIG. 10A) for CTLA4Ig (lane 1),
L104EIg (lane 2), and L104EA29YIg (lane 3A); and size exclusion
chromatographs of CTLA4Ig (FIG. 10B) and L104EA29YIg (FIG.
10C).
[0029] FIGS. 11A and 11B illustrate a ribbon diagram of the CTLA4
extracellular Ig V-like fold generated from the solution structure
determined by NMR spectroscopy. FIG. 11B shows an expanded view of
the S25-R33 region and the MYPPPY region indicating the location
and side-chain orientation of the avidity enhancing mutations, L104
and A29.
[0030] FIG. 12 depicts a schematic diagram of a vector,
piLN-L104EA29Y, having the L104EA29YIg insert.
[0031] FIG. 13 depicts nucleotide and amino acid sequence of CTLA4
receptor (SEQ ID NOS: 9 and 10).
DETAILED DESCRIPTION OF THE INVENTION
Definitions
[0032] All scientific and technical terms used in this application
have meanings commonly used in the art unless otherwise specified.
As used in this application, the following words or phrases have
the meanings specified.
[0033] As used herein, "ligand" refers to a molecule that
specifically recognizes and binds another molecule, for example, a
ligand for CTLA4 is a B7 molecule.
[0034] As used herein "wild type CTLA4" or "non-mutated CTLA4" has
the amino acid sequence of naturally occurring, full length CTLA4
as shown in FIG. 13 (SEQ ID NOS: 9 and 10; also as described U.S.
Pat. Nos. 5,434,131, 5,844,095, 5,851,795), or any portion or
derivative thereof, that recognizes and binds a B7 or interferes
with a B7 so that it blocks binding to CD28 and/or CTLA4 (e.g.,
endogenous CD28 and/or CTLA4). In particular embodiments, the
extracellular domain of wild type CTLA4 begins with methionine at
position +1 and ends at aspartic acid at position +124, or the
extracellular domain of wild type CTLA4 begins with alanine at
position -1 and ends at aspartic acid at position +124. Wild type
CTLA4 is a cell surface protein, having an N-terminal extracellular
domain, a transmembrane domain, and a C-terminal cytoplasmic
domain. The extracellular domain binds to target molecules, such as
a B7 molecule. In a cell, the naturally occurring, wild type CTLA4
protein is translated as an immature polypeptide, which includes a
signal peptide at the N-terminal end. The immature polypeptide
undergoes post-translational processing, which includes cleavage
and removal of the signal peptide to generate a CTLA4 cleavage
product having a newly generated N-terminal end that differs from
the N-terminal end in the immature form. One skilled in the art
will appreciate that additional post-translational processing may
occur, which removes one or more of the amino acids from the newly
generated N-terminal end of the CTLA4 cleavage product.
Alternatively, the signal peptide may not be removed completely,
generating molecules that begin before the common starting amino
acid methionine. Thus, the mature CTLA4 protein may start at
methionine at position +1 or alanine at position -1. The mature
form of the CTLA4 molecule includes the extracellular domain or any
portion thereof, which binds to B7.
[0035] "CTLA4Ig" is a soluble fusion protein comprising an
extracellular domain of wildtype CTLA4 joined to an Ig tail, or a
portion thereof that binds a B7. A particular embodiment comprises
the extracellular domain of wild type CTLA4 (as shown in FIG. 9,
SEQ ID NOS: 7 and 8) starting at methionine at position +1 and
ending at aspartic acid at position +124; or starting at alanine at
position -1 to aspartic acid at position +124; a junction amino
acid residue glutamine at position +125; and an immunoglobulin
portion encompassing glutamic acid at position +126 through lysine
at position +357 or glycine at position +356 (DNA encoding CTLA4Ig
was deposited on May 31, 1991 with the American Type Culture
Collection (ATCC), 10801 University Blvd., Manassas, Va. 20110-2209
under the provisions of the Budapest Treaty, and has been accorded
ATCC accession number ATCC 68629; Linsley, P., et al., 1994
Immunity 1:793-80. CTLA4Ig-24, a Chinese Hamster Ovary (CHO) cell
line expressing CTLA4Ig was deposited on May 31, 1991 with ATCC
identification number CRL-10762). The soluble CTLA4Ig molecules may
or may not include a signal (leader) peptide sequence.
[0036] As used herein, a "fusion protein" is defined as one or more
amino acid sequences joined together using methods well known in
the art and as described in U.S. Pat. No. 5,434,131 or 5,637,481.
The joined amino acid sequences thereby form one fusion
protein.
[0037] As used herein, "soluble" refers to any molecule, or
fragments and derivatives thereof, not bound or attached to a cell,
i.e., circulating. For example, CTLA4, B7 or CD28 can be made
soluble by attaching an immunoglobulin (Ig) moiety to the
extracellular domain of CTLA4, B7 or CD28, respectively.
Alternatively, a molecule such as CTLA4 can be rendered soluble by
removing its transmembrane domain.
[0038] As used herein "the extracellular domain of CTLA4" is the
portion of CTLA4 that recognizes and binds CTLA4 ligands, such as
B7 molecules. For example, an extracellular domain of CTLA4
comprises methionine at position +1 to aspartic acid at position
+124 (FIG. 13, SEQ ID NOS: 9 and 10). Alternatively, an
extracellular domain of CTLA4 comprises alanine at position -1 to
aspartic acid at position +124 (FIG. 13, SEQ ID NOS: 9 and 10). The
extracellular domain includes fragments or derivatives of CTLA4
that bind a B7 molecule. The extracellular domain of CTLA4 as shown
in FIG. 13 (SEQ ID NOS: 9 and 10) may also include mutations that
change the binding avidity of the CTLA4 molecule for a B7
molecule.
[0039] As used herein, a "CTLA4 mutant molecule" means wildtype
CTLA4 as shown in (SEQ ID NOS: 9 and 10) or any portion or
derivative thereof, that has a mutation or multiple mutations
(preferably in the extracellular domain of wildtype CTLA4). A CTLA4
mutant molecule has a sequence that it is similar but not identical
to the sequence of wild type CTLA4 molecule, but still binds a B7.
The mutations may include one or more amino acid residues
substituted with an amino acid having conservative (e.g.,
substitute a leucine with an isoleucine) or non-conservative (e.g.,
substitute a glycine with a tryptophan) structure or chemical
properties, amino acid deletions, additions, frameshifts, or
truncations. CTLA4 mutant molecules may include a non-CTLA4
molecule therein or attached thereto. The mutant molecules may be
soluble (i.e., circulating) or bound to a cell surface. Additional
CTLA4 mutant molecules include those described in U.S. patent
application Ser. Nos. 09/865,321, 60/214,065 and 60/287,576; in
U.S. Pat. Nos. 6,090,914 5,844,095 and 5,773,253; and as described
by Peach, R. J., et al., in J Exp Med 180:2049-2058 (1994)). CTLA4
mutant molecules can be made synthetically or recombinantly.
[0040] "L104EA29YIg" is a fusion protein that is a soluble CTLA4
mutant molecule comprising an extracellular domain of wildtype
CTLA4 with amino acid changes A29Y (a tyrosine amino acid residue
substituting for an alanine at position 29) and L104E (a glutamic
acid amino acid residue substituting for a leucine at position
+104), or a portion thereof that binds a B7 molecule, joined to an
Ig tail (included in FIG. 7, SEQ ID NOS: 3 and 4; DNA encoding
L104EA29YIg was deposited on Jun. 20, 2000 with ATCC number
PTA-2104; copending in U.S. patent application Ser. Nos.
09/579,927, 60/287,576 and 60/214,065, incorporated by reference
herein). The soluble L104EA29YIg molecules used in the methods
and/or kits of the invention may or may not include a signal
(leader) peptide sequence. Typically, in the methods and/or kits of
the invention, the molecules do not include a signal peptide
sequence.
[0041] As used herein, the term "mutation" means a change in the
nucleotide or amino acid sequence of a wildtype molecule, for
example, a change in the DNA and/or amino acid sequences of the
wild-type CTLA4 extracellular domain. A mutation in DNA may change
a codon leading to a change in the amino acid sequence. A DNA
change may include substitutions, deletions, insertions,
alternative splicing, or truncations. An amino acid change may
include substitutions, deletions, insertions, additions,
truncations, or processing or cleavage errors of the protein.
Alternatively, mutations in a nucleotide sequence may result in a
silent mutation in the amino acid sequence as is well understood in
the art. In that regard, certain nucleotide codons encode the same
amino acid. Examples include nucleotide codons CGU, CGG, CGC, and
CGA encoding the amino acid, arginine (R); or codons GAU, and GAC
encoding the amino acid, aspartic acid (D). Thus, a protein can be
encoded by one or more nucleic acid molecules that differ in their
specific nucleotide sequence, but still encode protein molecules
having identical sequences. The amino acid coding sequence is as
follows:
TABLE-US-00001 One Sym- Letter Amino Acid bol Symbol Codons Alanine
Ala A GCU, GCC, GCA, GCG Cysteine Cys C UGU, UGC Aspartic Acid Asp
D GAU, GAC Glutamic Acid Glu E GAA, GAG Phenylalanine Phe F UUU,
UUC Glycine Gly G GGU, GGC, GGA, GGG Histidine His H CAU, CAC
Isoleucine Ile I AUU, AUC, AUA Lysine Lys K AAA, AAG Leucine Leu L
UUA, UUG, CUU, CUC, CUA, CUG Methionine Met M AUG Asparagine Asn N
AAU, AAC Proline Pro P CCU, CCC, CCA, CCG Glutamine Gln Q CAA, CAG
Arginine Arg R CGU, CGC, CGA, CGG, AGA, AGG Serine Ser S UCU, UCC,
UCA, UCG, AGU, AGC Threonine Thr T ACU, ACC, ACA, ACG Valine Val V
GUU, GUC, GUA, GUG Tryptophan Trp W UGG Tyrosine Tyr Y UAU, UAC
The mutant molecule may have one or more mutations.
[0042] As used herein, a "non-CTLA4 protein sequence" or "non-CTLA4
molecule" means any protein molecule that does not bind B7 and does
not interfere with the binding of CTLA4 to its target. An example
includes, but is not limited to, an immunoglobulin (Ig) constant
region or portion thereof. Preferably, the Ig constant region is a
human or monkey Ig constant region, e.g., human C (gamma)1,
including the hinge, CH2 and CH3 regions. The Ig constant region
can be mutated to reduce its effector functions (U.S. Pat. Nos.
5,637,481, 5,844,095 and 5,434,131).
[0043] As used herein, a "fragment" or "portion" is any part or
segment of a CTLA4 molecule, preferably the extracellular domain of
CTLA4 or a part or segment thereof, that recognizes and binds its
target, e.g., a B7 molecule. The extracellular domain of CTLA4 may
include mutations that change the binding avidity of the CTLA4
molecule for a B7 molecule.
[0044] As used herein, "B7" refers to the B7 family of molecules
including, but not limited to, B7-1 (CD80), B7-2 (CD86) and B7-3
that may recognize and bind CTLA4 and/or CD28.
[0045] As used herein, "B7-positive cells" are any cells with one
or more types of B7 molecules expressed on the cell surface.
[0046] As used herein, a "derivative" is a molecule that shares
sequence homology and activity of its parent molecule. For example,
a derivative of CTLA4 includes a soluble CTLA4 molecule having an
amino acid sequence at least 70% similar to the extracellular
domain of wildtype CTLA4, and which recognizes and binds B7 e.g.,
CTLA4Ig or soluble CTLA4 mutant molecule L104EA29YIg.
[0047] As used herein, to "regulate" an immune response is to
activate, stimulate, up-regulate, inhibit, block, down-regulate or
modify the immune response. The autoimmune diseases described
herein, may be treated by regulating an immune response e.g., by
regulating functional CTLA4- and/or CD28-positive cell interactions
with B7-positive cells. For example, a method for regulating an
immune response comprises contacting the B7-positive cells with a
soluble CTLA4 molecule of the invention so as to form soluble
CTLA4/B7 complexes, the soluble CTLA4 molecule interfering with
reaction of an endogenous CTLA4 and/or CD28 molecule with said B7
molecule.
[0048] As used herein, to "block" or "inhibit" a receptor, signal
or molecule means to interfere with the activation of the receptor,
signal or molecule, as detected by an art-recognized test. Blockage
or inhibition may be partial or total. For example, blockage of a
cell-mediated immune response can be detected by determining the
functionality of the transplant, such as the serum creatinine
concentrations following renal transplantation.
[0049] As used herein, "blocking B7 interaction" means to interfere
with the binding of B7 to its ligands, such as CD28 and/or CTLA4,
thereby obstructing T-cell and B7-positive cell interactions.
Examples of agents that block B7 interactions include, but are not
limited to, molecules such as an antibody (or portion or derivative
thereof) that recognizes and binds to the any of CTLA4, CD28 or B7
molecules (e.g., B7-1, B7-2); a soluble form (or portion or
derivative thereof) of the molecules such as soluble CTLA4; a
peptide fragment or other small molecule designed to interfere with
the cell signal through the CTLA4/CD28/B7-mediated interaction. In
a preferred embodiment, the blocking agent is a soluble CTLA4
mutant molecule, such as L104EA29YIg (ATCC PTA-2104).
[0050] As used herein, "treat" or "treating" a disorder or disease
means to manage a disease or disorder by medicinal or other
therapies. Treatment of a disease or disorder may suppress
immune-mediated events associated with a disease, ameliorate the
symptoms of a disease or disorder, reduce the severity of a disease
or disorder, alter the course of disease or disorder progression
and/or ameliorate or cure the basic disease or disorder problem.
For example, to treat an immune disorder associated with graft
transplantation may be accomplished by regulating an immune
response e.g., by regulating functional CTLA4- and/or CD28-positive
cell interactions with B7-positive cells. Alternatively, treating
an immune disease or disorder may be accomplished by preventing or
inhibiting the disease or disorder from occurring or progressing
through the use of the compositions described herein. For example,
treating renal transplant rejection includes inhibition of renal
transplant rejection as measured by glomerular filtration rate
(GFR). For example treating immune disorders associated with graft
transplantation includes prophylaxis of organ rejection by
administration of L104EA29YIg. Further, treating immune disorders
associated with graft transplantation may prolong the survival of
the host and transplanted organ.
[0051] As used herein, "immune system disease" includes any disease
mediated by T-cell interactions with B7-positive cells including,
but not limited to, autoimmune diseases, immunoproliferative
diseases, and immune disorders associated with graft
transplantation.
[0052] As used herein, "immune disorders associated with graft
transplantation" means any transplant related disease mediated by
T-cell interactions with B7-positive cells including, but not
limited to, immune disorders associated with graft transplantation
rejection, graft related disorders, graft versus host disease
(GVHD) (e.g., such as may result from bone marrow transplantation,
or in the induction of tolerance), rejection of the graft or
transplant including acute rejection of the graft or transplant and
chronic rejection of the graft or transplant. The graft may be
solid organ allografts or xenografts, tissue or cell allografts or
xenografts or external anatomy allografts or xenografts, including
but not limited to skin, islet cells (also known as islets),
muscles, hepatocytes, neurons, heart, liver, kidney, lung,
appendages, limbs, nose, ear or face.
[0053] As used herein, immunoproliferative diseases include, but
are not limited to, T cell lymphoma; T cell acute lymphoblastic
leukemia; testicular angiocentric T cell lymphoma; and benign
lymphocytic angiitis.
[0054] As used herein autoimmune diseases include, but are not
limited to diseases such as lupus (e.g., lupus erythematosus, lupus
nephritis), psoriasis; Hashimoto's thyroiditis, primary myxedema,
Graves' disease, pernicious anemia, autoimmune atrophic gastritis,
Addison's disease, diabetes (e.g., insulin dependent diabetes
mellitus, type I diabetes mellitus, type II diabetes mellitus),
good pasture's syndrome, myasthenia gravis, pemphigus, Crohn's
disease, inflamatory bowl disease (IBD), sympathetic ophthalmia,
autoimmune uveitis, multiple sclerosis, autoimmune hemolytic
anemia, idiopathic thrombocytopenia, primary biliary cirrhosis,
chronic action hepatitis, ulcerative colitis, Sjogren's syndrome,
rheumatic diseases (e.g., rheumatoid arthritis, psoriatic
arthritis), polymyositis, scleroderma, and mixed connective tissue
disease.
[0055] In order that the invention herein described may be more
fully understood, the following description is set forth.
Compositions and Methods of the Invention
[0056] The present invention provides a new class of
immunosuppressive therapy for transplantation. It is a fusion
protein that binds to the B7 molecules on the surface of
antigen-presenting cells (APCs) inhibiting requisite co-stimulation
for T-cell activation. The soluble CTLA4 mutant molecules of the
invention differ from existing immunosuppressants in the restricted
distribution of its molecular target and the specificity of its
effect. The present invention provides soluble CTLA4 mutant
molecules that recognize and bind CD80 and/or CD86. In some
embodiments, the soluble CTLA4 mutants have a higher avidity to
CD80 and/or CD86 than CTLA4Ig. For example, L104EA29YIg binds
approximately 2-fold more avidly than wild type CTLA4Ig
(hereinafter referred to as CTLA4Ig) to CD80 and approximately
4-fold more avidly to CD86. This stronger binding results in
L104EA29YIg being more affective than CTLA4Ig at blocking immune
responses.
[0057] One embodiment of the present invention provides methods for
treating immune system diseases. The methods comprise administering
a therapeutic composition, comprising soluble CTLA4 mutant
molecules disclosed herein, to a subject in an amount effective to
relieve at least one of the symptoms associated with immune system
diseases. Additionally, the soluble CTLA4 mutant molecules
disclosed herein may provide long-term therapy for immune system
diseases by blocking the T-cell/B7-positive cell interactions,
thereby blocking T-cell activation/stimulation by co-stimulatory
signals such as B7 binding to CD28, leading to induction of T-cell
anergy or tolerance. Immune system diseases include, but are not
limited to, autoimmune diseases, immunoproliferative diseases, and
immune disorders associated with graft transplantation discussed
above.
[0058] Another embodiment provides methods for inducing tolerance
in a subject having immune disorders associated with graft
transplantation by administering a therapeutic composition
comprising soluble CTLA4 mutant molecules disclosed herein.
[0059] The soluble CTLA4 mutant molecules disclosed herein exhibit
inhibitory properties in vivo. Under conditions where
T-cell/B7-positive cell interactions, for example T cell/B cell
interactions, are occurring as a result of contact between T cells
and B7-positive cells, binding of introduced CTLA4 mutant molecules
to react to B7-positive cells, for example B cells, may interfere,
i.e., inhibit, the T cell/B7-positive cell interactions resulting
in regulation of immune responses.
[0060] Another embodiment provides methods for regulating immune
responses. Immune responses downregulated (reduced) by the soluble
CTLA4 mutant molecules disclosed herein may be by way of inhibiting
or blocking an immune response already in progress or may involve
preventing the induction of an immune response. The soluble CTLA4
mutant molecules disclosed herein may inhibit the functions of
activated T cells, such as T lymphocyte proliferation, cytokine
secretion and/or cytokine production, by suppressing T cell
responses or by inducing specific tolerance in T cells, or both.
Further, the soluble CTLA4 mutant molecules disclosed herein,
interfering with the CTLA4/CD28/B7 pathway may inhibit T-cell
proliferation and/or cytokine secretion, and thus result in reduced
tissue destruction and induction of T-cell unresponsiveness or
anergy.
[0061] CTLA4 mutant molecules comprise at least the extracellular
domain of CTLA4, or portions thereof that bind CD80 and/or CD86.
The extracellular portion of a CTLA4 mutant molecule comprises an
amino acid sequence starting with methionine at position +1 through
aspartic acid at position +124 (FIG. 7, SEQ ID NOS: 3 and 4; or
FIG. 8, SEQ ID NOS: 5 and 6). Alternatively, the extracellular
portion of the CTLA4 can comprise an amino acid sequence starting
with alanine at position -1 through aspartic acid at position +124
(FIG. 7, SEQ ID NOS: 3 and 4; or FIG. 8, SEQ ID NOS: 5 and 6).
[0062] In one embodiment, the soluble CTLA4 mutant molecule is a
fusion protein comprising the extracellular domain of CTLA4 having
one or more mutations in a region of an amino acid sequence
beginning with serine at +25 and ending with arginine at +33
(S25-R33). For example, the alanine at position +29 of wild type
CTLA4 can be substituted with tyrosine (codons: UAU, UAC).
Alternatively, alanine can be substituted with leucine (codons:
UUA, UUG, CUU, CUC, CUA, CUG), phenylalanine (codons: UUU, UUC),
tryptophan (codon: UGG), or threonine (codons: ACU, ACC, ACA, ACG).
As persons skilled in the art will readily understand, the uracil
(U) nucleotide of the RNA sequence corresponds to the thymine (T)
nucleotide of the DNA sequence.
[0063] In another embodiment, the soluble CTLA4 mutant molecule is
a fusion protein comprising the extracellular domain of CTLA4
having one or more mutations in or near a region of an amino acid
sequence beginning with methionine at +97 and ending with glycine
at +107 (M97-G107). For example, leucine at position +104 of wild
type CTLA4 can be substituted with glutamic acid (codons: GAA,
GAG). A CTLA4 mutant molecule having this substitution is referred
to herein as L104EIg (FIG. 8, SEQ ID NOS: 5 and 6).
[0064] In yet another embodiment, the soluble CTLA4 mutant molecule
is a fusion protein comprising the extracellular domain of CTLA4
having one or more mutations in the S25-R33 and M97-G107 regions.
For example, in one embodiment, a CTLA4 mutant molecule comprises
tyrosine at position +29 instead of alanine; and glutamic acid at
position +104 instead of leucine. A CTLA4 mutant molecule having
these substitutions is referred to herein as L104EA29YIg (FIG. 7,
SEQ ID NOS: 3 and 4). The nucleic acid molecule that encodes
L104EA29YIg is contained in pD16 L104EA29YIg and was deposited on
Jun. 19, 2000 with the American Type Culture Collection (ATCC),
10801 University Blvd., Manasas, Va. 20110-2209 (ATCC No.
PTA-2104). The pD16 L104EA29YIg vector is a derivative of the
pcDNA3 vector (INVITROGEN).
[0065] The invention further provides a soluble CTLA4 mutant
molecule comprising an extracellular domain of a CTLA4 mutant as
shown in FIG. 7 (SEQ ID NOS: 3 and 4) or FIG. 8 (SEQ ID NOS: 5 and
6) or portion(s) thereof, and a moiety that alters the solubility,
affinity and/or valency of the CTLA4 mutant molecule.
[0066] In accordance with a practice of the invention, the moiety
can be an immunoglobulin constant region or portion thereof, e.g.,
one or more of a CH1 domain, hinge, CH2 domain or CH3 domain. For
in vivo use, it is preferred that the immunoglobulin constant
region does not elicit a detrimental immune response in the
subject. For example, in clinical protocols, it may be preferred
that mutant molecules include human or monkey immunoglobulin
constant regions or portion thereof. Examples of suitable
immunoglobulin domains include, but are not limited to, IgC.gamma.1
(IgCgamma1), IgC.gamma.2 (IgCgamma2), IgC.gamma.3 (IgCgamma3),
IgC.gamma.4 (IgCgamma4), IgC.mu. (IgCmu), IgC.alpha.1 (IgCalpha1),
IgC.alpha.2 (IgCalpha2), IgC.delta. (IgCdelta) or IgC.epsilon.
(IgCepsilon). Other isotypes are possible. Further, other
immunoglobulin constant regions or portion thereof are possible
(preferably other weakly or non-immunogenic immunoglobulin constant
regions or portion thereof).
[0067] For clinical protocols, it is preferred that the
immunoglobulin moiety does not elicit a detrimental immune response
in a subject. The preferred moiety is the immunoglobulin constant
region or portion thereof, including the human or monkey
immunoglobulin constant regions or portion thereof. One example of
a suitable immunoglobulin region is human C.gamma.1, including the
hinge, CH2 and CH3 regions which can mediate effector functions
such as binding to Fc receptors, mediating complement-dependent
cytotoxicity (CDC), or mediate antibody-dependent cell-mediated
cytotoxicity (ADCC). The immunoglobulin moiety may have one or more
mutations therein, (e.g., in the CH2 domain, to reduce effector
functions such as CDC or ADCC) where the mutation modulates the
binding capability of the immunoglobulin to its ligand, by
increasing or decreasing the binding capability of the
immunoglobulin to Fc receptors. For example, mutations in the
immunoglobulin moiety may include changes in any or all its
cysteine residues within the hinge domain, for example, the
cysteines at positions +130, +136, and +139 are substituted with
serine (FIG. 9, SEQ ID NO: 8). The immunoglobulin moiety may also
include the proline at position +148 substituted with a serine, as
shown in FIG. 9 (SEQ ID NO: 8). Further, the mutations in the
immunoglobulin moiety may include having the leucine at position
+144 substituted with phenylalanine, leucine at position +145
substituted with glutamic acid, or glycine at position +147
substituted with alanine. Examples of immunoglobuling moieties
include those described and disclosed in U.S. Patent Publications
Nos. 2002/0114814 A1 and 2004/0151725 A1, U.S. Pat. Nos. 6,444,792
and 6,750,334, and WO 97/28267.
[0068] Other moieties include polypeptide tags. Examples of
suitable tags include but are not limited to the p97 molecule, env
gp120 molecule, E7 molecule, and ova molecule (Dash, B., et al.
(1994) J. Gen. Virol. 75:1389-97; Ikeda, T., et al. (1994) Gene
138:193-6; Falk, K., et al. (1993) Cell. Immunol. 150:447-52;
Fujisaka, K. et al. (1994) Virology 204:789-93). Other molecules
for use as tags are possible (Gerard, C. et al. (1994) Neuroscience
62:721-739; Byrn, R. et al. J. Virol. (1989) 63:4370-4375; Smith,
D. et al., (1987) Science 238:1704-1707; Lasky, L., (1996) Science
233:209-212).
[0069] The invention further provides soluble mutant CTLA4Ig fusion
proteins preferentially more reactive with the CD80 and/or CD86
antigen compared to wild type CTLA4. One example is L104EA29YIg as
shown in FIG. 7 (SEQ ID NOS: 3 and 4).
[0070] In another embodiment, the soluble CTLA4 mutant molecule
includes a junction amino acid residue, which is located between
the CTLA4 portion and the immunoglobulin portion. The junction
amino acid can be any amino acid, including glutamine. The junction
amino acid can be introduced by molecular or chemical synthesis
methods known in the art.
[0071] In another embodiment, the soluble CTLA4 mutant molecule
includes the immunoglobulin portion (e.g., hinge, CH2 and CH3
domains), where any or all of the cysteine residues, within the
hinge domain of the immunoglobulin portion are substituted with
serine, for example, the cysteines at positions +130, +136, or +139
(FIG. 7, SEQ ID NOS: 3 and 4; or FIG. 8, SEQ ID NOS: 5 and 6). The
mutant molecule may also include the proline at position +148
substituted with a serine, as shown in FIG. 7 (SEQ ID NOS: 3 and 4)
or FIG. 8 (SEQ ID NOS: 5 and 6).
[0072] The soluble CTLA4 mutant molecule can include a signal
peptide sequence linked to the N-terminal end of the extracellular
domain of the CTLA4 portion of the mutant molecule. The signal
peptide can be any sequence that will permit secretion of the
mutant molecule, including the signal peptide from oncostatin M
(Malik, et al., (1989) Molec. Cell. Biol. 9: 2847-2853), or CD5
(Jones, N. H. et al., (1986) Nature 323:346-349), or the signal
peptide from any extracellular protein.
[0073] The mutant molecule can include the oncostatin M signal
peptide linked at the N-terminal end of the extracellular domain of
CTLA4, and the human immunoglobulin molecule (e.g., hinge, CH2 and
CH3) linked to the C-terminal end of the extracellular domain of
CTLA4. This molecule includes the oncostatin M signal peptide
encompassing an amino acid sequence having methionine at position
-26 through alanine at position -1, the CTLA4 portion encompassing
an amino acid sequence having methionine at position +1 through
aspartic acid at position +124, a junction amino acid residue
glutamine at position +125, and the immunoglobulin portion
encompassing an amino acid sequence having glutamic acid at
position +126 through lysine at position +357 or glycine at
position +356.
[0074] The soluble CTLA4 mutant molecules of the invention can be
obtained by molecular or chemical synthesis methods. The molecular
methods may include the following steps: introducing a suitable
host cell with a nucleic acid molecule that expresses and encodes
the soluble CTLA4 mutant molecule; culturing the host cell so
introduced under conditions that permit the host cell to express
the mutant molecules; and isolating the expressed mutant molecules.
The signal peptide portion of the mutant molecule permits the
protein molecules to be expressed on the cell surface and to be
secreted by the host cell. The translated mutant molecules can
undergo post-translational modification, involving cleavage of the
signal peptide to produce a mature protein having the CTLA4 and the
immunoglobulin portions. The cleavage may occur after the alanine
at position -1, resulting in a mature mutant molecule having
methionine at position +1 as the first amino acid (FIG. 7, SEQ ID
NOS: 3 and 4; or FIG. 8, SEQ ID NOS: 5 and 6). Alternatively, the
cleavage may occur after the methionine at position -2, resulting
in a mature mutant molecule having alanine at position -1 as the
first amino acid.
[0075] One skilled in the art would be aware that expression of
L104EA29YIg in mammalian cells can result in the production of N-
and C-terminal variants, such that the proteins produced can have
the amino acid sequence of residues: (i) +1 to +357, (ii) -1 to
+357; (iii) +1 to +356 or (iv) -1 to 356 (FIG. 7, SEQ ID NOS: 3 and
4; or FIG. 8, SEQ ID NOS: 5 and 6).
[0076] A preferred embodiment is a soluble CTLA4 mutant molecule
having the extracellular domain of human CTLA4 linked to all or a
portion of a human immunoglobulin molecule (e.g., hinge, CH2 and
CH3). This preferred molecule includes the CTLA4 portion of the
soluble molecule encompassing an amino acid sequence having
methionine at position +1 through aspartic acid at position +124, a
junction amino acid residue glutamine at position +125, and the
immunoglobulin portion encompassing glutamic acid at position +126
through lysine at position +357 or glycine at position +356. The
portion having the extracellular domain of CTLA4 is mutated so that
alanine at position +29 is substituted with tyrosine and leucine at
position +104 is substituted with glutamic acid. The immunoglobulin
portion of the mutant molecule can be mutated, so that the
cysteines at positions +130, +136, and +139 are substituted with
serine, and the proline at position +148 is substituted with
serine. This mutant molecule is designated herein as L104EA29YIg
(FIG. 7, SEQ ID NOS: 3 and 4).
[0077] Another embodiment of L104EA29YIg is a mutant molecule
having an amino acid sequence having alanine at position -1 through
aspartic acid at position +124, a junction amino acid residue
glutamine at position +125, and the immunoglobulin portion
encompassing glutamic acid at position +126 (e.g., +126 through
lysine at position +357 or glycine at position +356). The portion
having the extracellular domain of CTLA4 is mutated so that alanine
at position +29 is replaced with tyrosine; and leucine at position
+104 is replaced with glutamic acid. The immunoglobulin portion of
the mutant molecule is mutated so that the cysteines at positions
+130, +136, and +139 are replaced with serine, and the proline at
position +148 is replaced with serine. This mutant molecule is
designated herein as L104EA29YIg (FIG. 7, SEQ ID NOS: 3 and 4).
After the signal sequence has been cleaved, L104EA29YIg can either
begin with a methionine at position +1, or begin with alanine at
position -1.
[0078] Another mutant molecule of the invention is a soluble CTLA4
mutant molecule having the extracellular domain of human CTLA4
linked to the human immunoglobulin molecule (e.g., hinge, CH2 and
CH3). This molecule includes the portion of the amino acid sequence
encoding CTLA4 starting with methionine at position +1 through
aspartic acid at position +124, a junction amino acid residue
glutamine at position +125, and the immunoglobulin portion
encompassing an amino acid sequence having glutamic acid at
position +126 through lysine at position +357 or glycine at
position +356. The portion having the extracellular domain of CTLA4
is mutated so that leucine at position +104 is substituted with
glutamic acid. The hinge portion of the mutant molecule is mutated
so that the cysteines at positions +130, +136, and +139 are
substituted with serine, and the proline at position +148 is
substituted with serine. This mutant molecule is designated herein
as L104EIg (FIG. 8, SEQ ID NOS: 5 and 6).
[0079] Alternatively, an embodiment of L104EIg is a soluble CTLA4
mutant molecule having an extracellular domain of human CTLA4
linked to a human immunoglobulin molecule (e.g., hinge, CH2 and
CH3). This preferred molecule includes the CTLA4 portion
encompassing an amino acid sequence beginning with alanine at
position -1 through aspartic acid at position +124, a junction
amino acid residue glutamine at position +125, and the
immunoglobulin portion encompassing glutamic acid at position +126
through lysine at position +357 or glycine at position +356. The
portion having the extracellular domain of CTLA4 is mutated so that
leucine at position +104 is substituted with glutamic acid. The
hinge portion of the mutant molecule is mutated so that the
cysteines at positions +130, +136, and +139 are substituted with
serine, and the proline at position +148 is substituted with
serine. This mutant molecule is designated herein as L104EIg (FIG.
8, SEQ ID NOS: 5 and 6).
[0080] Further, the invention provides a soluble CTLA4 mutant
molecule having: (a) a first amino acid sequence of a membrane
glycoprotein, e.g., CD28, CD86, CD80, CD40, and gp39, which blocks
T cell proliferation, fused to a second amino acid sequence; (b)
the second amino acid sequence being a fragment of the
extracellular domain of mutant CTLA4 which blocks T cell
proliferation, such as, for example an amino acid molecule
comprising methionine at position +1 through aspartic acid at
position +124 (FIG. 7, SEQ ID NOS: 3 and 4; or FIG. 8, SEQ ID NOS:
5 and 6); and (c) a third amino acid sequence which acts as an
identification tag or enhances solubility of the molecule. For
example, the third amino acid sequence can consist essentially of
amino acid residues of the hinge, CH2 and CH3 regions of a
non-immunogenic immunoglobulin molecule. Examples of suitable
immunoglobulin molecules include, but are not limited to, human or
monkey immunoglobulin, e.g., IgC.gamma.1. Other isotypes are also
possible.
[0081] The present invention also provides a method for treating an
immune disorder associated with graft transplantation by
administering to a subject an effective dose of a CTLA4 mutant
molecule with an extracellular domain of CTLA4 as shown in SEQ ID
NO:8 beginning with alanine at position 26 or methionine at
position 27 and ending with aspartic acid at position 150, or a
portion thereof. Additionally, in the extracellular domain or
portion thereof an alanine at position 55 is substituted with a
tyrosine, and a leucine at position 130 is substituted with a
glutamic acid. Further the administration regimen comprises an
early phase regimen, wherein the early phase regimen may range from
the first 3 to 6 months post-transplantation and involves
administration that initially is more frequent than monthly.
[0082] Additionally, the present invention provides a method for
treating an immune disorder associated with graft transplantation
by administering to a subject an effective dose of a CTLA4 mutant
molecule with an amino acid sequence beginning with methionine at
position 27 and ending with aspartic acid at position 150 of SEQ ID
NO:4, or with an amino acid sequence beginning with alanine at
position 26 and ending with aspartic acid at position 150 of SEQ ID
NO:4. Further the CTLA4 mutant molecule administration regimen
comprises an early phase regimen, wherein the early phase regimen
may range from the first 3 to 6 months post-transplantation and
involves administration that initially is more frequent than
monthly.
[0083] The invention further provides nucleic acid molecules
comprising nucleotide sequences encoding the amino acid sequences
corresponding to the soluble CTLA4 mutant molecules of the
invention. In one embodiment, the nucleic acid molecule is a DNA
(e.g., cDNA) or a hybrid thereof. Alternatively, the nucleic acid
molecules are RNA or a hybrids thereof.
[0084] Additionally, the invention provides a vector, which
comprises the nucleotide sequences of the invention. A host vector
system is also provided. The host vector system comprises the
vector of the invention in a suitable host cell. Examples of
suitable host cells include, but are not limited to, prokaryotic
and eukaryotic cells.
[0085] The invention includes pharmaceutical compositions for use
in the treatment of immune disorders associated with graft
transplantation comprising pharmaceutically effective doses of
soluble CTLA4 mutant molecules. In certain embodiments, the immune
disorders associated with graft transplantation are mediated by
CD28- and/or CTLA4-positive cell interactions with CD80 and/or CD86
positive cells. The soluble CTLA4 mutant molecules are preferably
CTLA4 molecules having one or more mutations in the extracellular
domain of CTLA4. The pharmaceutical composition can include soluble
CTLA4 mutant protein molecules and/or nucleic acid molecules,
and/or vectors encoding the molecules. In preferred embodiments,
the soluble CTLA4 mutant molecules have the amino acid sequence of
the extracellular domain of CTLA4 as shown in either FIGS. 7 (SEQ
ID NOS: 3 and 4) or 8 (SEQ ID NOS: 5 and 6), L104EA29Y or L104E,
respectively. Even more preferably, the soluble CTLA4 mutant
molecule is L104EA29YIg as disclosed herein. The compositions may
additionally include other therapeutic agents, including, but not
limited to, drug toxins, enzymes, antibodies, or conjugates.
[0086] The pharmaceutical compositions also preferably include
suitable carriers and adjuvants which include any material which
when combined with the molecule of the invention (e.g., a soluble
CTLA4 mutant molecule, such as, L104EA29Y or L104E) retains the
molecule's activity and is non-reactive with the subject's immune
system. Examples of suitable carriers and adjuvants include, but
are not limited to, human serum albumin; ion exchangers; alumina;
lecithin; buffer substances, such as phosphates; glycine; sorbic
acid; potassium sorbate; and salts or electrolytes, such as
protamine sulfate. Other examples include any of the standard
pharmaceutical carriers such as a phosphate buffered saline
solution; water; emulsions, such as oil/water emulsion; and various
types of wetting agents. Other carriers may also include sterile
solutions; tablets, including coated tablets and capsules.
Typically such carriers contain excipients such as starch, milk,
sugar, certain types of clay, gelatin, stearic acid or salts
thereof, magnesium or calcium stearate, talc, vegetable fats or
oils, gums, glycols, or other known excipients. Such carriers may
also include flavor and color additives or other ingredients.
Compositions comprising such carriers are formulated by well known
conventional methods. Such compositions may also be formulated
within various lipid compositions, such as, for example, liposomes
as well as in various polymeric compositions, such as polymer
microspheres.
[0087] The pharmaceutical compositions of the invention can be
administered using conventional modes of administration including,
but not limited to, intravenous (i.v.) administration,
intraperitoneal (i.p.) administration, intramuscular (i.m.)
administration, subcutaneous administration, oral administration,
administration as a suppository, or as a topical contact, or the
implantation of a slow-release device such as a miniosmotic pump,
to the subject.
[0088] The pharmaceutical compositions of the invention may be in a
variety of dosage forms, which include, but are not limited to,
liquid solutions or suspensions, tablets, pills, powders,
suppositories, polymeric microcapsules or microvesicles, liposomes,
and injectable or infusible solutions. The preferred form depends
upon the mode of administration and the therapeutic
application.
[0089] A typical pharmaceutical composition of the invention, for
intravenous (i.v.) administration is listed below.
TABLE-US-00002 Composition of lyophilized L104EA29YIg 100 mg/vial
drug product Component Amount/Vial (mg).sup.a L104EA29YIg
110.sup.a.sup. Sucrose 220 Sodium Phosphate Monobasic Monohydrate
15.18 Sodium Chloride 2.55 1N Sodium Hydroxide Adjust to pH 7.5 1N
Hydrochloric Acid Adjust to pH 7.5 .sup.aEach vial contains 10%
overfill for vial, needle and syringe holdup of the reconstituted
solution.
[0090] The lyophilized drug product may be constituted with an
aqueous carrier. The aqueous carrier of interest herein is one
which is pharmaceutically acceptable (safe and non-toxic for
administration to a human) and is useful for the preparation of a
liquid formulation, after lyophilization. Typically, the
lyophilized drug product is constituted to about 25 mg/ml with 10
ml of either Sterile Water for Injection, USP (SWFI) or 0.9% Sodium
Chloride Injection, USP. The constituted solution is further
diluted to drug product concentrations between 1 and 10 mg/ml with
0.9% Sodium Chloride Injection, USP. The diluted drug product for
injection is isotonic and suitable for administration by
intravenous infusion.
[0091] A surfactant may be added to the formulation in an amount
sufficient to reduce or prevent the interaction of the constituted
drug product with a siliconized syringe.
[0092] The most effective mode of administration and dosage regimen
for the compositions of this invention depends upon the severity
and course of the disease, the patient's health and response to
treatment and the judgment of the treating physician. Accordingly,
the dosages (also known as doses) of the compositions should be
titrated to the individual patient.
[0093] The soluble CTLA4 mutant molecules may be administered to a
subject in an amount, at a frequency over a period of a time (e.g.,
length of time and/or multiple times) sufficient to block
endogenous B7 (e.g., CD80 and/or CD86) molecules from binding their
respective ligands, in the subject. Blockage of endogenous
B7/ligand binding thereby inhibits interactions between B7-positive
cells (e.g., CD80- and/or CD86-positive cells) with CD28- and/or
CTLA4-positive cells. Dosage of a therapeutic agent is dependant
upon many factors including, but not limited to, the type of tissue
affected, the type of immune disorder associated with graft
transplantation being treated, the severity of the disease, a
subject's health, and a subject's response to the treatment with
the agents.
[0094] Doses of the molecules or the pharmaceutical compositions of
the invention are based on body weight, and administration regimens
may be dictated by the target serum trough profiles. Typically,
target trough serum concentration of CTLA4 mutant molecules of the
invention between about 3 .mu.g/mL and about 30 .mu.g/mL over the
first 3 to 6 months post-transplant will be sufficient to maintain
function of the allograft, preferably between about 5 .mu.g/mL and
about 20 .mu.g/mL. Typically, target trough serum concentration of
CTLA4 mutant molecules of the invention during the maintenance
phase are between about 0.2 .mu.g/mL and about 3 .mu.g/mL,
preferably between about 0.25 .mu.g/mL and about 2.5 .mu.g/mL.
[0095] The CTLA4 mutant molecules of the invention may be
administered in an amount between about 0.1 to about 20.0 mg/kg
weight of the patient, typically between about 1.0 to about 15.0
mg/kg. For example, L104EA29Y may be administered at 10 mg/kg
weight of the patient during the early phase, high risk period that
follows transplantation and decreased to 5 mg/kg weight of the
patient for a maintenance dosage.
[0096] Administration of the molecules or pharmaceutical
compositions of the invention can be performed over various times.
Typically, administration regimens include an early phase, in which
doses are higher and the frequency of administration is increased
during the period of greatest immunologic risk, followed by a
maintenance phase. The early phase regimen may range from the first
3 to 6 months post-transplantation and involves administration that
initially is more frequent than monthly, preferably as frequently
as daily, weekly or every two weeks depending on the immunologic
risk and/or target trough serum concentration. The maintenance
phase begins when the early phase ends and involves administration
that is not more frequent than monthly, and lasts for as long as
needed, typically for as long as the patient retains the
transplant. As used herein, day 1 is defined as the day of the
transplant or the first day of treatment with molecules or
pharmaceutical compositions of the invention.
[0097] The dosage of CTLA4 mutant molecules of the invention in the
early phase is about 8 to about 12 mg/kg weight of the patient,
preferably about 10 mg/kg. The dosage of CTLA4 mutant molecules of
the invention in the maintenance phase is about 3 to about 7 mg/kg
weight of the patient, preferably about 5 mg/kg.
[0098] The early phase may range from the first 3 to 6 months
post-transplantation. The administration regimen during early phase
may vary depending on the status of the recipient and/or graft. For
example, a more intensive early phase regimen would administer a
higher dose of the molecules or the pharmaceutical compositions of
the invention on day 1, day 5, week 2 visit (e.g., day 13-17), then
every two weeks for the first 3 months (e.g., on week 4 visit, week
6 visit, week 8 visit, week 10 visit, and week 12 visit), followed
by monthly administration through month 6 visit (e.g., on month 4
visit, month 5 visit, and month 6 visit). An example of a typical
more intensive early phase regimen is administration of 10 mg/kg
weight of the patient of L104EA29YIg at days 1, 5, 15, 29, 43, 57,
71, 85, 113, 141 and 169. A less intensive regimen, for example,
would administer the molecules or the pharmaceutical compositions
of the invention on day 1, week 2 visit, week 4 visit, then monthly
through month 3 visit. An example of a typical less intensive early
phase regimen is administration of 10 mg/kg weight of the patient
of L104EA29YIg on days 1, 15, 29, 57 and 85.
[0099] Typically, an early phase is followed by a maintenance phase
where lower doses of the molecules or pharmaceutical compositions
of the invention are administered at one to two month intervals for
as long as needed, typically for as long as the patient retains the
transplant. An example of the maintenance phase for the more
intensive regimen described above includes monthly administration
of 5 mg/kg weight of the patient of L104EA29YIg starting at month 7
visit. While an example of the maintenance phase for the less
intensive regimen above would include monthly administration of 5
mg/kg weight of the patient of L104EA29YIg starting at month 4
visit.
[0100] Alternatively, one knowledgeable in the art would be able to
modify the administration regimen in response to the patients risk
status and/or response to the therapy post transplantation. For
example, the early phase of the less intensive regimen described
above could be modified by adding administration day 5 to the
regimen, thereby increasing the frequency of administration during
the period of greatest immunologic risk.
[0101] As used herein, "four weeks," "month", "months" or "monthly"
refers to a period of 28.+-.5 days. As used herein, "two weeks"
refers to a period of 14.+-.3 days.
[0102] Flexibility in the administration regimens is required to
facilitate administration scheduling in the lives of transplant
recipients, while maintaining the target trough profile of the
CTLA4 mutant molecules of the invention. Permitted windows for
administering the doses may be as follows:
TABLE-US-00003 Visit Visit window Day 1 and day 5 96 hours apart
.+-. 6 hours Week 2 Target date .+-. 2 days Week 4-Month 6 Target
date .+-. 3 days from Month 7 thereafter Target date .+-. 5
days
[0103] The target date is a result of adding the desired duration
to the previous actual visit date. The desired duration for the
week 2 visit is 10 days. The desired duration is 14 days for a
visit planned for two weeks from the previous visit, e.g., a week 6
visit following a week 4 visit. The desired duration is 28 days for
a visit planned for a month or four week from the previous visit,
e.g., a month 4 visit following a month 3 visit. The desired
duration is 56 days for a visit planned for two months from the
previous visit, e.g., a month 8 visit after a month 6 visit. For
example, a day 15 actual visit date plus 14 days results in a week
4 target date of day 29. Based on the visit windows above, the
administration may occur on day 29.+-.3 days. Should the
administration occur on day 26, that day becomes the actual visit
date utilized for the calculation of the next target date.
[0104] Low risk of acute rejection recipients typically include
those who receive transplants from living related donors and well
matched recipient/donors. High risk of acute rejection recipients
typically include those who receive transplants from marginal
donors or re-transplants, have high panel reactive antibodies or
are African American.
[0105] In addition to the immediate risk of acute transplant
rejection, the use of maintenance drugs such as calcineurin
inhibitors and steroids over the long term result in toxicities
that negatively impact long-term outcomes and patient quality of
life. For example, side effects of maintenance drugs include
nephrotoxicity (CAN) resulting in declining renal function and/or
graft loss, and cardiovascular and metabolic diseases such as
hypertension, hyperlipidemia and diabetes which result in
cardiovascular disease and death. Additional side effects include
hirsuitism, alpecia, gingival hyperplasia, tremor, neurotoxicity
and bone loss which result in non-compliance and reduced quality of
life. The molecules or pharmaceutical compositions of the invention
maybe used to avoid these outcomes, to reduce incidence,
development and/or progression of these outcomes when treating
immune disorders associated with graft transplantation, or to treat
immune disorders associated with graft transplantation in subjects
at risk of these outcomes. The molecules or pharmaceutical
compositions of the invention maybe used to improve renal function
such as measured by GFR.
[0106] The administration of the molecules or pharmaceutical
compositions of the invention can be via a 30 minute to one or more
hour intravenous infusion. Alternatively, single to multiple
subcutaneous injections can deliver the required dosage. Typically,
a 30 minute intravenous infusion is the administration route
utilized during the early phase of treatment while the patient is
in the hospital and/or making scheduled visits to the healthcare
professional for monitoring. The subcutaneous injection is the
typical administration mode utilized during the maintenance phase,
thereby allowing the patient to return to their normal schedule by
decreasing the visits to a healthcare professional for intravenous
infusions.
[0107] An alternate embodiment of the invention provides a method
for treating an immune disorder associated with graft
transplantation in subjects that have received an alternate
immunosuppressive therapy post transplantation. The subjects on an
alternate pharmaceutical immunosuppressive therapy may change or
switch or convert to a therapy including the molecules or
pharmaceutical compositions of the present invention, thereby
eliminating the alternate drug. Typically the pharmaceutical that
is to be eliminated is ramped down over an appropriate period of
time, based on the prescribing instructions of that specific drug,
while at the same time the molecules or pharmaceutical composition
of the instant invention is administered more frequently than
monthly. Once the subject is completely off the alternate drug, the
subject may return to a standard maintenance regimen utilizing the
molecules or pharmaceutical compositions of the instant invention.
For example, a subject receiving CsA/MMF.+-.corticosteroid regimen
may switch CsA with L104EA29YIg for a
L104EA29YIg/MMF.+-.corticosteroid regimen. The conversion
administration schedule may include a ramping down of the dose of
CsA over two months and the administration of 5 mg/kg of
L104EA29YIg every two weeks during those two months. Once the CsA
is eliminated, the subject would then enter the maintenance phase
and continue to receive 5 mg/kg every 4 or 8 weeks for the duration
of the treatment in the absence of CsA.
[0108] One embodiment provides appropriate dosages for a soluble
CTLA4 mutant molecule disclosed herein that is effective for
blocking B7 interactions with its ligand and/or treating an immune
system disease. For example the dosage may be based on body weight,
and administration regimens may be dictated by the target serum
trough profiles. For example, the effective target trough serum
concentrations of soluble CTLA4 mutant molecules disclosed herein
to treat an immune system disease may be between about 0.2 .mu.g/mL
and about 30 .mu.g/mL. Alternatively, the soluble CTLA4 mutant
molecules disclosed herein may be administered in an amount between
about 0.1 to about 20.0 mg/kg weight of the patient to treat immune
system diseases.
[0109] The present invention further provides methods for treating
immune disorders associated with graft transplantation. In
particular embodiments, the immune disorders associated with graft
transplantation are mediated by CD28- and/or CTLA4-positive cell
interactions with CD80/CD86-positive cells. In a further
embodiment, T cell interactions are inhibited. These methods
comprise administering to a subject the soluble CTLA4 mutant
molecules of the invention to regulate T cell interactions with the
CD80- and/or CD86-positive cells. Examples of immune disorders
associated with graft transplantation are discussed above.
[0110] The present invention further provides a method for
prophylaxis of or inhibiting or preventing solid organ, tissue,
cell and/or external anatomy transplant rejections by a subject,
the subject being a recipient of transplant solid organ, tissue,
cell and/or external anatomy. Typically, in transplants, rejection
of the graft is initiated through its recognition as foreign by T
cells, followed by an immune response that destroys the graft. The
soluble CTLA4 mutant molecules of this invention, by inhibiting T
lymphocyte proliferation and/or cytokine secretion, may result in
reduced tissue destruction and induction of antigen-specific T cell
unresponsiveness which may result in long-term graft
acceptance.
[0111] The study described in Example 3 compared the efficacy and
safety of L104EA29YIg as a maintenance immunosuppressant with
cyclosporineA (CsA) over 12 months when used as part of a CNI-free
combination regimen consisting of basiliximab (Simulect.RTM.;
Novartis) induction, mycophenolate mofetil (MMF; CellCept.RTM.;
Roche), and corticosteroids in renal transplant recipients.
Objectives included assessment of the incidence of acute rejection
(biopsy-confirmed or presumed) at 6 months and 1 year; measured
glomerular filtration rate (GFR) via iohexyl clearance at 1, 6, and
12 months; parameters of hypertension including serum cholesterol
and triglycerides; and overall safety. Other pre-specified analyses
included patient death or graft loss at 1 year; the severity of
acute rejection; the incidence of post-transplant diabetes mellitus
[defined as any therapy required for hyperglycemia for .gtoreq.4
weeks, or a hemoglobin A1C (HbA1c)>7%, in patients not
previously known to be diabetic]; calculated GFR, using the
Modification of Diet in Renal Disease (MDRD, Levey A S, Bosch J P,
Lewis J P, Greene T, Rogers N, Roth D. A more accurate method to
estimate glomerular filtration rate from serum creatinine: a new
prediction equation. Modification of Diet in Renal Disease Study
Group. Ann Intern Med 1999; 130:461-470), Jelliffe (R W. Creatinine
clearance: Bedside estimate. Ann Inter Med. 1973; 79:604-605),
Cockcroft-Gault (Cockcroft D W, Gault M H. Prediction of creatinine
clearance from serum creatinine. Nephron 1976; 16:31-41), and
Nankivell (Nankivell B J, Gruenewald S M, Allen R D, Chapman J R.
Predicting glomerular filtration rate after kidney transplantation.
Transplantation. 1995; 59(12):1683-1689) formulas; pharmacokinetics
and immunogenicity. Diagnosis and treatment of acute rejection (AR)
was based on the Banff 97 criteria and grade (Racusen L C, Solez K,
Colvin R B, et al. The Banff 97 working classification of renal
allograft pathology. Kidney Int 1999; 55(2):713-23.). Post hoc
analysis was conducted of the incidence of chronic allograft
nephropathy (CAN).
[0112] This 12-month study demonstrated that L104EA29YIg-based
maintenance therapy conferred equivalent efficacy in preventing AR
and similar patient and graft survival compared with CsA. In
addition, L104EA29YIg demonstrated significant improvements in
renal function and reductions in CAN compared with CsA-based
maintenance immunosuppression. L104EA29YIg was safe and well
tolerated and was not associated with typical CNI-related
toxicities.
[0113] Improved renal function during the first post-transplant
year has been shown to correlate with better long-term outcomes
(Hariharan S, McBride M A, Cherikh W S, Tolleris C B, Bresnahan B
A, Johnson C P. Post-transplant renal function in the first year
predicts long-term kidney transplant survival. Kidney Int 2002;
62(1):311-8) since the long-term use of CNIs is limited by their
nephrotoxicity (Danovitch G M. Immunosuppressive medications for
renal transplantation: a multiple choice question. Kidney Int 2001;
59(1):388-402), which leads to reduced graft function and renal
insufficiency with all its attendant problems. Thus, perhaps the
most notable findings seen with L104EA29YIg treatment are the
superior GFRs coupled with the 12-month renal histology showing
reductions in development and/or progression of CAN compared with
CsA. This was a surprising outcome and the first time that a
finding of this sort has been shown in a randomized Phase II trial
of an immunosuppressive therapy. Since preservation of the nephron
mass, by prevention of immunologic, cardiovascular and/or metabolic
insults contributes to beneficial effects on both patient and graft
survival it is possible that L104EA29YIg may be associated with
better long-term outcomes.
[0114] These issues are particularly important with the increasing
use of organs from extended criteria donors or recipients since
these are particularly susceptible to CNI-related toxicity.
Decreasing the incidence of CV and metabolic events in patients who
have undergone renal transplant is also central to improving
long-term outcomes.
[0115] The molecules or pharmaceutical compositions of the
invention maybe used to treat immune disorders associated with
graft transplantation in subjects who are extended criteria
recipients and/or who are receiving grafts from extended criteria
donors. These criteria, which are based in part on criteria issued
by the United Network of Organ Sharing (UNOS), may include one or
more of the following: donor age less than 10 or greater than or
equal to 60 years; donor after cardiac death; anticipated
cold-ischemic time of donor organ greater than or equal to 24
hours; subjects undergoing first time transplant with a current
PRA.gtoreq.50%, or undergoing retransplantation with
PRA.gtoreq.30%; subjects with previous graft loss due to acute
rejection during the first 6 months after transplant; subjects with
positive T-cell lymphocytotoxic crossmatch using donor lymphocytes
and recipient serum; subjects with HIV infection; subjects with
active tuberculosis requiring treatment within the previous 3
years; or other criteria issued by the United Network of Organ
Sharing (UNOS). An example of possible extended criteria for a
donor and/or the donor kidney includes at least 1 of the following
extended criteria for organ donation a) Donor age .gtoreq.60 years
OR b) Donor age 50-59 years and 1 of the following: (i)
Cerebrovascular accident (CVA)+hypertension+SCr>1.5 mg/dL OR
(ii) CVA+hypertension OR (iii) CVA+SCr>1.5 mg/dL OR (iv)
Hypertension+SCr>1.5 mg/dL OR c) CIT.gtoreq.24 hours, donor age
>10 years OR d) Donor with cardiac death (non-heart beating
donor).
[0116] The present invention also provides methods for inhibiting
graft versus host disease in a subject. This method comprises
administering to the subject a soluble CTLA4 mutant molecule of the
invention, alone or together, concomitantly or sequentially, with
further additional ligands, reactive with IL-2, IL-2R, IL-4, or
.gamma.-interferon. For example, a soluble CTLA mutant molecule of
this invention may be administered to a bone marrow transplant
recipient to inhibit the alloreactivity of donor T cells.
Alternatively, donor T cells within a bone marrow graft may be
tolerized to a recipient's alloantigens ex vivo prior to
transplantation.
[0117] The soluble CTLA4 mutant molecules of the invention, for
example L104EA29Y, may be administered as the sole active
ingredient or together, concomitantly or sequentially, with one or
more other drugs in immunomodulating regimens, immunosuppressive
agents and/or other anti-inflammatory agents e.g., for the
treatment, prevention or inhibition or prophylaxis of allograft or
xenograft acute or chronic rejection or to induce tolerance. For
example, it may be used in combination with a calcineurin inhibitor
(e.g., cyclosporin A or FK506); an immunosuppressive macrolide
(e.g., tacrolimus, rapamycin, sirolimus) or a derivative thereof
(e.g., 40-O-(2-hydroxy)ethyl-rapamycin, sirolimus, centican); a
lymphocyte homing agent (e.g., FTY720) or an analog thereof (FK778,
Jak-3), corticosteroids; cyclophosphamide; azathioprene;
methotrexate; leflunomide or an analog thereof; mizoribine;
mycophenolic acid; mycophenolate mofetil; 15-deoxyspergualine or an
analog thereof; immunosuppressive monoclonal antibodies (e.g.,
basiliximab, daclizumab), ligands, monoclonal antibodies or
antibody fragments thereof to leukocyte receptors (e.g., MHC, CD2,
CD3, CD4, CD11a/CD18, CD7, CD25, CD 27, B7, CD40, CD45, CD58, CD
137, ICOS, CD150 (SLAM), OX40, 4-1BBor their ligands); or other
immunomodulatory compounds (e.g., CTLA4/CD28-Ig), or other adhesion
molecule inhibitors (e.g., mAbs) or low molecular weight inhibitors
including LFA-1 antagonists, Selectin antagonists and VLA-4
antagonists. The compound is particularly useful in combination
with a compound which interferes with CD40 and its ligand (e.g.,
antibodies to CD40 and antibodies to CD40-L), such as Chi220 (U.S.
Pat. No. 6,051,228) e.g., in the above described indications, e.g
the induction of tolerance.
[0118] Where the soluble CTLA4 mutant molecules of the invention
are administered concomitantly or sequentially in conjunction with
other immunosuppressive/immunomodulatory therapy, e.g as herein
specified, dosages of the co-administered immunosuppressant, or
immunomodulatory compound will of course vary depending on the type
of co-drug employed, e.g., whether it is a steroid or a
cyclosporine, on the specific drug employed, on the condition being
treated and so forth.
[0119] In accordance with the foregoing, the present invention
further provides therapeutic combinations, e.g., a kit, e.g., for
use in any method as defined above, comprising a L104EA29YIg, in
free form or in pharmaceutically acceptable salt form, to be used
concomitantly or in sequence with at least one pharmaceutical
composition comprising an immunosuppressant, immunomodulatory or
anti-inflammatory drug. The kit may comprise instructions for its
administration.
[0120] In accordance with the foregoing the present invention
provides in a yet further aspect methods as defined above
comprising co-administration, e.g., concomitantly or in sequence,
of a therapeutically effective dose of soluble CTLA4 mutant
molecule of the invention, with immunosuppressive agents.
Immunosuppressive agents include soluble gp39 (also known as CD40
ligand (CD40L), CD154, T-BAM, TRAP), soluble CD29, soluble CD40,
soluble CD80 (e.g., ATCC 68627), soluble CD86, soluble CD28 (e.g.,
68628), soluble CD56, soluble Thy-1, soluble CD3, soluble TCR,
soluble VLA-4, soluble VCAM-1, soluble LECAM-1, soluble ELAM-1,
soluble CD44, ligands, antibodies or antibody fragments reactive
with gp39 (e.g., ATCC HB-10916, ATCC HB-12055 and ATCC HB-12056),
ligands, antibodies or antibody fragments reactive with CD40 (e.g.,
ATCC HB-9110), ligands, antibodies or antibody fragments reactive
with B7 (e.g., ATCC HB-253, ATCC CRL-2223, ATCC CRL-2226, ATCC
HB-301, ATCC HB-11341, etc), ligands, antibodies or antibody
fragments reactive with CD28 (e.g., ATCC HB-11944 or mAb 9.3 as
described by Martin et al (J. Clin. Immun. 4(1):18-22, 1980),
ligands, antibodies or antibody fragments reactive with LFA-1
(e.g., ATCC HB-9579 and ATCC TIB-213), ligands, antibodies or
antibody fragments reactive with LFA-2, ligands, antibodies or
antibody fragments reactive with IL-2 or IL-2R, ligands, antibodies
or antibody fragments reactive with IL-12, ligands, antibodies or
antibody fragments reactive with IFN-gamma, ligands, antibodies or
antibody fragments reactive with CD2, antibodies ligands,
antibodies or antibody fragments reactive with CD48, ligands,
antibodies or antibody fragments reactive with any ICAM (e.g.,
ICAM-1 (ATCC CRL-2252), ICAM-2 and ICAM-3), ligands, antibodies or
antibody fragments reactive with CTLA4 (e.g., ATCC HB-304),
ligands, antibodies or antibody fragments reactive with Thy-1,
ligands, antibodies or antibody fragments reactive with CD56,
ligands, antibodies or antibody fragments reactive with CD3,
ligands, antibodies or antibody fragments reactive with CD29,
ligands, antibodies or antibody fragments reactive with TCR,
ligands, antibodies or antibody fragments reactive with VLA-4,
ligands, antibodies or antibody fragments reactive with VCAM-1,
ligands, antibodies or antibody fragments reactive with LECAM-1,
ligands, antibodies or antibody fragments reactive with ELAM-1,
ligands, antibodies or antibody fragments reactive with CD44. In
certain embodiments, monoclonal antibodies are preferred. In other
embodiments, antibody fragments are preferred. Antibody fragments
include but are not limited to Fab, Fab', F(ab').sub.2, Fv, scFv
and domain antibodies (dAbs) including but not limited to those
described in WO2006/030220. As persons skilled in the art will
readily understand, the combination can include the soluble CTLA4
mutant molecules of the invention and one other immunosuppressive
agent, the soluble CTLA4 mutant molecules with two other
immunosuppressive agents, the soluble CTLA4 molecules with three
other immunosuppressive agents, etc. The determination of the
optimal combination and dosages can be determined and optimized
using methods well known in the art.
[0121] A particularly useful combination is L104EA29YIg or
pharmaceutical composition thereof with a compound that interferes
with IL-2 and its ligand, specifically an antagonist targeted
against IL-2R (alpha) which is selectively expressed on the surface
of activated T-lymphocytes. A compound that binds to IL-2R(alpha)
competitively inhibits IL-2 mediated activation of lymphocytes,
which is a critical pathway in the cellular immune response
involved in allograft rejection.
[0122] Some specific combinations include the following:
L104EA29YIg and CD80 monoclonal antibodies (mAbs); L104EA29YIg and
CD86 mAbs; L104EA29YIg, CD80 mAbs, and CD86 mAbs; L104EA29YIg and
gp39 mAbs; L104EA29YIg and CD40 mAbs; L104EA29YIg and CD28 mAbs;
L104EA29YIg, CD80 and CD86 mAbs, and gp39 mAbs; L104EA29YIg, CD80
and CD86 mAbs and CD40 mAbs; and L104EA29YIg, anti-LFA1 mAb, and
anti-gp39 mAb. A specific example of a gp39 mAb is MR1. Other
combinations will be readily appreciated and understood by persons
skilled in the art.
[0123] In accordance with the foregoing the present invention
provides in a yet further aspect methods as defined above
comprising co-administration, e.g., concomitantly or in sequence,
of a therapeutically effective dose of soluble CTLA4 mutant
molecule of the invention, with an adjunctive agent and/or a
corticosteroid. The goal is to replace the toxic calcineurin
inhibitors with the CTLA4 mutant molecules of the invention.
However, the CTLA4 mutant molecules of the invention also may be
co-administered concomitantly or sequentially with CNIs such as
cyclosporine (Neoral.RTM., Sandimmune.RTM. from Novartis) and
tacrolimus (FK506, Prograf.RTM. from Fujisawa).
[0124] Examples of adjunctive agents include but are not limited to
inhibitors of inosine monophosphate dehydrogenase (IMPDH), e.g.,
mycopheriolate mofetil (MMF, Cellcept.RTM. from Roche Laboratories)
and mycophenolic acid (Myfortic.RTM. from Novartis); rapamycin
(sirolimus, Rapamune.RTM. from Wyeth/Ayerst); azathioprine
(Azarsan.RTM. from Salix, Imuran.RTM., generic); a lymphocyte
homing agent, e.g., FTY720 (from Novartis); FK778 (from Fujisawa);
Jak-3 (from Pfizer); and Certican.RTM. (everolimus from
Novartis).
[0125] Examples of corticosteroids include but are not limited to,
betamethasone, budesonide, cortisol, cortisone, dexamethasone,
hydrocritisone, methylprednisolone, prednisolone, prednisone and
triamcinolone.
[0126] Typical co-administration combinations include but are not
limited to L104EA29YIg and at least one adjunctive agent selected
from the group listed above; L104EA29YIg and at least one
corticosteroid selected from the group listed above; L104EA29YIg,
MMF (Cellcept from Roche) and a corticosteroid selected from the
group listed above; L104EA29YIg, rapamycin (sirolimus,
Rapamune.RTM. from Wyeth/Ayerst) with or without a corticosteroid
selected from the group listed above.
[0127] The co-administration combinations described above may be
utilized with an induction agent such as immunosuppressive
monoclonal antibodies, e.g., basiliximab (Simulect.RTM. from
Novartis), muromonab (Orthoclone OKT3.RTM. from Ortho Biotech),
rituximab (Rituxan.RTM. from Genentech) and daclizumab
(Zenapax.RTM. from Roche Labs); or anti-thymocyte globulin
(Thymoglobulin.RTM. from SangStat). For example, suitable
combinations include but are not limited to basiliximab
(Simulect.RTM. from Novartis) with L104EA29YIg, MMF (Cellcept from
Roche) and prednisolone; or daclizumab (Zenapax.RTM. from Roche),
L104EA29YIg and rapamycin (sirolimus, Rapamune.RTM. from
Wyeth/Ayerst).
[0128] Typically, the standard dosages and administration regimen
of the co-administered drugs described above are not influenced by
the addition of the CTLA4 mutant molecules of the invention to the
treatment regimen. However, one knowledgeable in the art may
prescribe lower doses of the co-administered drugs, e.g.,
adjunctive agents and/or corticosteroids, due to the incorporation
of the less toxic CTLA4 mutant molecules of the invention into the
treatment regimen.
[0129] Prescribing information may be based on the package insert
for each co-administered drug. A corticosteroid may be
co-administered with the molecules or pharmaceutical composition of
the invention. For example, subjects may be treated daily with
corticosteroids. One steroid maintenance and taper strategy may
include 500 mg i.v. methylprednisolone on arrival in the operating
room (OR) 250 mg i.v. methylprednisolone on day 2, followed by
prednisone (or prednisolone) 100 mg orally on day 3, followed by a
taper of prednisone (or prednisolone) to 20-30 mg/day by the end of
week 2, followed by a taper of prednisone (or prednisolone) to no
lower than 2.5 mg/day through month 6. Subjects may remain on at
least 2.5 mg/day throughout the course of their treatment.
[0130] Additional co-administered drugs may include mycophenolate
mofetil (MMF). Typically MMF is administered in 2 divided doses on
a consistent schedule in relation to time of day and meals. An
example of an administration regimen for MMF includes 2 g daily.
The first dose can be administered preoperatively. Subsequent doses
may be administered p.o. as soon as the subject is able to tolerate
medications by mouth. The dose and schedule may be adjusted on the
basis of laboratory values (e.g., decreased WBCs) and subject
tolerability. The package insert provides full prescribing
information.
[0131] Another co-administered drug may include basiliximab.
Reconstituted basiliximab (20 mg in 5 mL) may be diluted to a
volume of 50 mL with normal saline or dextrose 5% and administered
as an i.v. infusion over 20-30 minutes. The first 20 mg dose may be
administered on Day 1 (the day of transplantation). The second 20
mg dose may be given on Day 5. The package insert provides full
prescribing information
[0132] Further provided are therapeutic combinations, e.g., a kit,
e.g., for use in any method as defined above, comprising a
L104EA29YIg, in free form or in pharmaceutically acceptable salt
form, to be used concomitantly or in sequence with at least one
pharmaceutical composition comprising an adjunctive agent and
corticosteroids. The kit may comprise instructions for its
administration.
[0133] The label and/or the instructions may indicate that the
pharmaceutical composition can be used alone, or in combination,
concomitantly or sequentially with a second agent to treat a
condition of choice e.g., immune system diseases, autoimmune
diseases, immunoproliferative diseases, immune disorders associated
with graft transplantation as described above.
[0134] The label may indicate appropriate dosages for the molecules
disclosed herein. For example, the label can indicate that dosages
for a molecule that is effective for blocking B7 interactions with
its ligand and/or treating an immune system disease may be based on
body weight, and administration regimens may be dictated by the
target serum trough profiles. For example, the label may indicate
that the effective target trough serum concentrations of CTLA4
mutant molecules disclosed herein to treat an immune system disease
may be between about 0.2 .mu.g/mL and about 30 .mu.g/mL.
Alternatively, the label may indicate that the CTLA4 mutant
molecules disclosed herein may be administered in an amount between
about 0.1 to about 20.0 mg/kg weight of the patient to treat immune
system diseases.
Methods for Producing the Molecules of the Invention
[0135] Expression of CTLA4 mutant molecules can be in prokaryotic
cells. Prokaryotes most frequently are represented by various
strains of bacteria. The bacteria may be a gram positive or a gram
negative. Typically, gram-negative bacteria such as E. coli are
preferred. Other microbial strains may also be used.
[0136] Sequences encoding CTLA4 mutant molecules can be inserted
into a vector designed for expressing foreign sequences in
prokaryotic cells such as E. coli. These vectors can include
commonly used prokaryotic control sequences which are defined
herein to include promoters for transcription initiation,
optionally with an operator, along with ribosome binding site
sequences, include such commonly used promoters as the
beta-lactamase (penicillinase) and lactose (lac) promoter systems
(Chang, et al., (1977) Nature 198:1056), the tryptophan (trp)
promoter system (Goeddel, et al., (1980) Nucleic Acids Res. 8:4057)
and the lambda derived P.sub.L promoter and N-gene ribosome binding
site (Shimatake, et al., (1981) Nature 292:128).
[0137] Such expression vectors will also include origins of
replication and selectable markers, such as a beta-lactamase or
neomycin phosphotransferase gene conferring resistance to
antibiotics, so that the vectors can replicate in bacteria and
cells carrying the plasmids can be selected for when grown in the
presence of antibiotics, such as ampicillin or kanamycin.
[0138] The expression plasmid can be introduced into prokaryotic
cells via a variety of standard methods, including but not limited
to CaCl.sub.2-shock (Cohen, (1972) Proc. Natl. Acad. Sci. USA
69:2110, and Sambrook et al. (eds.), "Molecular Cloning: A
Laboratory Manual", 2nd Edition, Cold Spring Harbor Press, (1989))
and electroporation.
[0139] In accordance with the practice of the invention, eukaryotic
cells are also suitable host cells. Examples of eukaryotic cells
include any animal cell, whether primary or immortalized, yeast
(e.g., Saccharomyces cerevisiae, Schizosaccharomyces pombe, and
Pichia pastoris), and plant cells. Myeloma, COS and CHO cells are
examples of animal cells that may be used as hosts. Particular CHO
cells include, but are not limited to, DG44 (Chasin, et al., 1986
Som. Cell. Molec. Genet. 12:555-556; Kolkekar 1997 Biochemistry
36:10901-10909), CHO-K1 (ATCC No. CCL-61), CHO-K1 Tet-On cell line
(Clontech), CHO designated ECACC 85050302 (CAMR, Salisbury,
Wiltshire, UK), CHO clone 13 (GEIMG, Genova, IT), CHO clone B
(GEIMG, Genova, IT), CHO-K1/SF designated ECACC 93061607 (CAMR,
Salisbury, Wiltshire, UK), and RR-CHOK1 designated ECACC 92052129
(CAMR, Salisbury, Wiltshire, UK). Exemplary plant cells include
tobacco (whole plants, cell culture, or callus), corn, soybean, and
rice cells. Corn, soybean, and rice seeds are also acceptable.
[0140] Nucleic acid sequences encoding the CTLA4 mutant molecules
can also be inserted into a vector designed for expressing foreign
sequences in a eukaryotic host. The regulatory elements of the
vector can vary according to the particular eukaryotic host.
[0141] Commonly used eukaryotic control sequences for use in
expression vectors include promoters and control sequences
compatible with mammalian cells such as, for example, CMV promoter
(CDM8 vector) and avian sarcoma virus (ASV) (.pi.LN vector). Other
commonly used promoters include the early and late promoters from
Simian Virus 40 (SV40) (Fiers, et al., (1973) Nature 273:113), or
other viral promoters such as those derived from polyoma,
Adenovirus 2, and bovine papilloma virus. An inducible promoter,
such as hMTII (Karin, et al., (1982) Nature 299:797-802) may also
be used.
[0142] Vectors for expressing CTLA4 mutant molecules in eukaryotes
may also carry sequences called enhancer regions. These are
important in optimizing gene expression and are found either
upstream or downstream of the promoter region.
[0143] Examples of expression vectors for eukaryotic host cells
include, but are not limited to, vectors for mammalian host cells
(e.g., BPV-1, pHyg, pRSV, pSV2, pTK2 (Maniatis); pIRES (Clontech);
pRc/CMV2, pRc/RSV, pSFV1 (Life Technologies); pVPakc Vectors, pCMV
vectors, pSG5 vectors (Stratagene)), retroviral vectors (e.g., pFB
vectors (Stratagene)), pcDNA-3 (Invitrogen) or modified forms
thereof, adenoviral vectors; Adeno-associated virus vectors,
baculovirus vectors, yeast vectors (e.g., pESC vectors
(Stratagene)).
[0144] Nucleic acid sequences encoding CTLA4 mutant molecules can
integrate into the genome of the eukaryotic host cell and replicate
as the host genome replicates. Alternatively, the vector carrying
CTLA4 mutant molecules can contain origins of replication allowing
for extrachromosomal replication.
[0145] For expressing the nucleic acid sequences in Saccharomyces
cerevisiae, the origin of replication from the endogenous yeast
plasmid, the 2.mu. circle can be used. (Broach, (1983) Meth. Enz.
101:307). Alternatively, sequences from the yeast genome capable of
promoting autonomous replication can be used (see, for example,
Stinchcomb et al., (1979) Nature 282:39); Tschemper et al., (1980)
Gene 10:157; and Clarke et al., (1983) Meth. Enz. 101:300).
[0146] Transcriptional control sequences for yeast vectors include
promoters for the synthesis of glycolytic enzymes (Hess et al.,
(1968) J. Adv. Enzyme Reg. 7:149; Holland et al., (1978)
Biochemistry 17:4900). Additional promoters known in the art
include the CMV promoter provided in the CDM8 vector (Toyama and
Okayama, (1990) FEBS 268:217-221); the promoter for
3-phosphoglycerate kinase (Hitzeman et al., (1980) J. Biol. Chem.
255:2073), and those for other glycolytic enzymes.
[0147] Other promoters are inducible because they can be regulated
by environmental stimuli or the growth medium of the cells. These
inducible promoters include those from the genes for heat shock
proteins, alcohol dehydrogenase 2, isocytochrome C, acid
phosphatase, enzymes associated with nitrogen catabolism, and
enzymes responsible for maltose and galactose utilization.
[0148] Regulatory sequences may also be placed at the 3' end of the
coding sequences. These sequences may act to stabilize messenger
RNA. Such terminators are found in the 3' untranslated region
following the coding sequences in several yeast-derived and
mammalian genes.
[0149] Exemplary vectors for plants and plant cells include, but
are not limited to, Agrobacterium T.sub.i plasmids, cauliflower
mosaic virus (CaMV), and tomato golden mosaic virus (TGMV).
[0150] General aspects of mammalian cell host system
transformations have been described by Axel (U.S. Pat. No.
4,399,216 issued Aug. 16, 1983). Mammalian cells can be transformed
by methods including but not limited to, transfection in the
presence of calcium phosphate, microinjection, electroporation, or
via transduction with viral vectors.
[0151] Methods for introducing foreign DNA sequences into plant and
yeast genomes include (1) mechanical methods, such as
microinjection of DNA into single cells or protoplasts, vortexing
cells with glass beads in the presence of DNA, or shooting
DNA-coated tungsten or gold spheres into cells or protoplasts; (2)
introducing DNA by making cell membranes permeable to
macromolecules through polyethylene glycol treatment or subjection
to high voltage electrical pulses (electroporation); or (3) the use
of liposomes (containing cDNA) which fuse to cell membranes.
[0152] Expression of CTLA4 mutant molecules can be detected by
methods known in the art. For example, the mutant molecules can be
detected by Coomassie staining SDS-PAGE gels and immunoblotting
using antibodies that bind CTLA4. Protein recovery can be performed
using standard protein purification means, e.g., affinity
chromatography or ion-exchange chromatography, to yield
substantially pure product (R. Scopes in: "Protein Purification,
Principles and Practice", Third Edition, Springer-Verlag
(1994)).
[0153] US patent application US Publication Number 2005/0019859,
2005/0084933 and WO 04/058944 teach a processes for the production
of proteins of the invention, specifically recombinant glycoprotein
products, by animal or mammalian cell cultures and are herein
incorporated by reference.
[0154] The invention further provides soluble CTLA4 mutant
molecules produced above herein.
CTLA4Ig Codon-Based Mutagenesis
[0155] In one embodiment, site-directed mutagenesis and a novel
screening procedure were used to identify several mutations in the
extracellular domain of CTLA4 that improve binding avidity for
CD86. In this embodiment, mutations were carried out in residues in
the regions of the extracellular domain of CTLA4 from serine 25 to
arginine 33, the C' strand (alanine 49 and threonine 51), the F
strand (lysine 93, glutamic acid 95 and leucine 96), and in the
region from methionine 97 through tyrosine 102, tyrosine 103
through glycine 107 and in the G strand at positions glutamine 111,
tyrosine 113 and isoleucine 115. These sites were chosen based on
studies of chimeric CD28/CTLA4 fusion proteins (Peach et al., J.
Exp. Med., 1994, 180:2049-2058), and on a model predicting which
amino acid residue side chains would be solvent exposed, and a lack
of amino acid residue identity or homology at certain positions
between CD28 and CTLA4. Also, any residue which is spatially in
close proximity (5 to 20 Angstrom Units) to the identified residues
is considered part of the present invention.
[0156] To synthesize and screen soluble CTLA4 mutant molecules with
altered affinities for CD80 and/or CD86, a two-step strategy was
adopted. The experiments entailed first generating a library of
mutations at a specific codon of an extracellular portion of CTLA4
and then screening these by BIAcore analysis to identify mutants
with altered reactivity to CD80 or CD86. The Biacore assay system
(Pharmacia, Piscataway, N.J.) uses a surface plasmon resonance
detector system that essentially involves covalent binding of
either CD80Ig or CD86Ig to a dextran-coated sensor chip which is
located in a detector. The test molecule can then be injected into
the chamber containing the sensor chip and the amount of
complementary protein that binds can be assessed based on the
change in molecular mass which is physically associated with the
dextran-coated side of the sensor chip; the change in molecular
mass can be measured by the detector system.
ADVANTAGES OF THE INVENTION
[0157] Because CTLA4 binding to CD80 and CD86 is characterized by
rapid "on" rates and rapid dissociation ("off") rates, and because
CTLA4Ig-CD86 complexes dissociate approximately 5- to 8-fold more
rapidly than CTLA4Ig-CD80 complexes, it was reasoned that slowing
the rate of dissociation of CTLA4 .mu.g from CD80 and/or CD86 would
result in molecules with more potent immunosuppressive properties.
Thus, soluble CTLA4 mutant molecules having a higher avidity for
CD80- or CD86-positive cells compared to wild type CTLA4, or
non-mutated forms of CTLA4Ig, are expected to block the priming of
antigen specific activated cells with higher efficiency than wild
type CTLA4 or non-mutated forms of CTLA4Ig.
EXAMPLES
[0158] The following examples are presented to illustrate the
present invention and to assist one of ordinary skill in making and
using the same. The examples are not intended in any way to
otherwise limit the scope of the invention.
Example 1
[0159] This example provides a description of the methods used to
generate the nucleotide sequences encoding the soluble CTLA4 mutant
molecules of the invention. A single-site mutant L104EIg was
generated and tested for binding kinetics for CD80 and/or CD86. The
L104EIg nucleotide sequence was used as a template to generate the
double-site mutant CTLA4 sequence, L104EA29YIg, which was tested
for binding kinetics for CD80 and/or CD86.
CTLA4Ig Codon Based Mutagenesis
[0160] A mutagenesis and screening strategy was developed to
identify mutant CTLA4Ig molecules that had slower rates of
dissociation ("off" rates) from CD80 and/or CD86 molecules.
Single-site mutant nucleotide sequences were generated using
CTLA4Ig (U.S. Pat. Nos. 5,844,095; 5,851,795; and 5,885,796; ATCC
Accession No. 68629) as a template. Mutagenic oligonucleotide PCR
primers were designed for random mutagenesis of a specific cDNA
codon by allowing any base at positions 1 and 2 of the codon, but
only guanine or thymine at position 3 (XXG/T; also known as NNG/T).
In this manner, a specific codon encoding an amino acid could be
randomly mutated to code for each of the 20 amino acids. In that
regard, XXG/T mutagenesis yields 32 potential codons encoding each
of the 20 amino acids. PCR products encoding mutations in close
proximity to -M97-G107 of CTLA4Ig (see FIG. 7, SEQ ID NOS: 3 and 4;
or FIG. 8, SEQ ID NOS: 5 and 6), were digested with SacI/XbaI and
subcloned into similarly cut CTLA4Ig .pi.LN (also known as piLN)
expression vector. This method was used to generate the single-site
CTLA4 mutant molecule L104EIg (FIG. 8, SEQ ID NOS: 5 and 6).
[0161] For mutagenesis in proximity to S25-R33 of CTLA4Ig, a silent
NheI restriction site was first introduced 5' to this loop, by PCR
primer-directed mutagenesis. PCR products were digested with
NheI/XbaI and subcloned into similarly cut CTLA4Ig or L104EIg
expression vectors. This method was used to generate the
double-site CTLA4 mutant molecule L104EA29YIg (FIG. 7, SEQ ID NOS:
3 and 4). In particular, the nucleic acid molecule encoding the
single-site CTLA4 mutant molecule, L104EIg, was used as a template
to generate the double-site CTLA4 mutant molecule, L104EA29YIg. The
piLN vector having the L104EA29YIg is shown in FIG. 12.
Example 2
[0162] The following provides a description of the screening
methods used to identify the single- and double-site mutant CTLA4
polypeptides, expressed from the constructs described in Example 1,
that exhibited a higher binding avidity for CD80 and CD86 antigens,
compared to non-mutated CTLA4Ig molecules.
[0163] Current in vitro and in vivo studies indicate that CTLA4Ig
by itself is unable to completely block the priming of antigen
specific activated T cells. In vitro studies with CTLA4Ig and
either monoclonal antibody specific for CD80 or CD86 measuring
inhibition of T cell proliferation indicate that anti-CD80
monoclonal antibody did not augment CTLA4Ig inhibition. However,
anti-CD86 monoclonal antibody did augment the inhibition,
indicating that CTLA4Ig was not as effective at blocking CD86
interactions. These data support earlier findings by Linsley et al.
(Immunity, (1994), 1:793-801) showing inhibition of CD80-mediated
cellular responses required approximately 100 fold lower CTLA4Ig
concentrations than for CD86-mediated responses. Based on these
findings, it was surmised that soluble CTLA4 mutant molecules
having a higher avidity for CD86 than wild type CTLA4 should be
better able to block the priming of antigen specific activated
cells than CTLA4Ig.
[0164] To this end, the soluble CTLA4 mutant molecules described in
Example 1 above were screened using a novel screening procedure to
identify several mutations in the extracellular domain of CTLA4
that improve binding avidity for CD80 and CD86. This screening
strategy provided an effective method to directly identify mutants
with apparently slower "off" rates without the need for protein
purification or quantitation since "off" rate determination is
concentration independent (O'Shannessy et al., (1993) Anal.
Biochem., 212:457-468).
[0165] COS cells were transfected with individual miniprep purified
plasmid DNA and propagated for several days. Three day conditioned
culture media was applied to BIAcore biosensor chips (Pharmacia
Biotech AB, Uppsala, Sweden) coated with soluble CD80Ig or CD86Ig.
The specific binding and dissociation of mutant proteins was
measured by surface plasmon resonance (O'Shannessy, D. J., et al.,
(1993) Anal. Biochem. 212:457-468). All experiments were run on
BIAcore.TM. or BIAcore.TM. 2000 biosensors at 25.degree. C. Ligands
were immobilized on research grade NCM5 sensor chips (Pharmacia)
using standard N-ethyl-N'-(dimethylaminopropyl)
carbodiimidN-hydroxysuccinimide coupling (Johnsson, B., et al.
(1991) Anal. Biochem. 198: 268-277; Khilko, S. N., et al. (1993) J.
Biol. Chem. 268:5425-15434).
Screening Method
[0166] COS cells grown in 24 well tissue culture plates were
transiently transfected with DNA encoding mutant CTLA4Ig. Culture
media containing secreted soluble mutant CTLA4Ig was collected 3
days later.
[0167] Conditioned COS cell culture media was allowed to flow over
BIAcore biosensor chips derivatized with CD86Ig or CD80Ig (as
described in Greene et al., 1996 J. Biol. Chem. 271:26762-26771),
and mutant molecules were identified with "off" rates slower than
that observed for wild type CTLA4Ig. The cDNAs corresponding to
selected media samples were sequenced and DNA was prepared to
perform larger scale COS cell transient transfection, from which
mutant CTLA4Ig protein was prepared following protein A
purification of culture media.
[0168] BIAcore analysis conditions and equilibrium binding data
analysis were performed as described in J. Greene et al. 1996 J.
Biol. Chem. 271:26762-26771, and as described herein.
BIAcore Data Analysis
[0169] Senosorgram baselines were normalized to zero response units
(RU) prior to analysis. Samples were run over mock-derivatized flow
cells to determine background response unit (RU) values due to bulk
refractive index differences between solutions. Equilibrium
dissociation constants (K.sub.d) were calculated from plots of
R.sub.eq versus C, where R.sub.eq is the steady-state response
minus the response on a mock-derivatized chip, and C is the molar
concentration of analyte. Binding curves were analyzed using
commercial nonlinear curve-fitting software (Prism, GraphPAD
Software).
[0170] Experimental data were first fit to a model for a single
ligand binding to a single receptor (1-site model, i.e., a simple
langmuir system, A+BAB), and equilibrium association constants
(K.sub.d=[A][B]\[AB]) were calculated from the equation
R=R.sub.maxC/(K.sub.d+C). Subsequently, data were fit to the
simplest two-site model of ligand binding (i.e., to a receptor
having two non-interacting independent binding sites as described
by the equation
R=R.sub.max1C\(K.sub.d1+C)+R.sub.max2C\(K.sub.d2+C)).
[0171] The goodness-of-fits of these two models were analyzed
visually by comparison with experimental data and statistically by
an F test of the sums-of-squares. The simpler one-site model was
chosen as the best fit, unless the two-site model fit significantly
better (p<0.1).
[0172] Association and disassociation analyses were performed using
BIA evaluation 2.1 Software (Pharmacia). Association rate constants
k.sub.on were calculated in two ways, assuming both homogenous
single-site interactions and parallel two-site interactions. For
single-site interactions, k.sub.on values were calculated according
to the equation R.sub.t=R.sub.eq(1-exp.sup.-ks(t-t.sub.0), where
R.sub.t is a response at a given time, t; R.sub.eq is the
steady-state response; to is the time at the start of the
injection; and k.sub.s=dR/dt=k.sub.onCk.sub.off, and where C is a
concentration of analyte, calculated in terms of monomeric binding
sites. For two-site interactions k.sub.on values were calculated
according to the equation
R.sub.t=R.sub.eq1(1-exp.sup.-ks1(t-t.sub.0.sup.)+R.sub.eq2(1-exp.sup.ks2(-
t-t.sub.0.sup.). For each model, the values of k.sub.on were
determined from the calculated slope (to about 70% maximal
association) of plots of k.sub.s versus C.
[0173] Dissociation data were analyzed according to one site
(AB=A+B) or two sites (AiBj=Ai+Bj) models, and rate constants
(k.sub.off) were calculated from best fit curves. The binding site
model was used except when the residuals were greater than machine
background (2-10 RU, according to machine), in which case the
two-binding site model was employed. Half-times of receptor
occupancy were calculated using the relationship
t.sub.1/2=0.693/k.sub.off.
Flow Cytometry
[0174] Murine mAb L307.4 (anti-CD80) was purchased from Becton
Dickinson (San Jose, Calif.) and IT2.2 (anti-B7-0 [also known as
CD86]), from Pharmingen (San Diego, Calif.). For immunostaining,
CD80-positive and/or CD86-positive CHO cells were removed from
their culture vessels by incubation in phosphate-buffered saline
(PBS) containing 10 mM EDTA. CHO cells (1-10.times.10.sup.5) were
first incubated with mAbs or immunoglobulin fusion proteins in DMEM
containing 10% fetal bovine serum (FBS), then washed and incubated
with fluorescein isothiocyanate-conjugated goat anti-mouse or
anti-human immunoglobulin second step reagents (Tago, Burlingame,
Calif.). Cells were given a final wash and analyzed on a FACScan
(Becton Dickinson).
SDS-PAGE and Size Exclusion Chromatography
[0175] SDS-PAGE was performed on Tris/glycine 4-20% acrylamide gels
(Novex, San Diego, Calif.). Analytical gels were stained with
Coomassie Blue, and images of wet gels were obtained by digital
scanning. CTLA4Ig (25 .mu.g) and L104EA29YIg (25 .mu.g) were
analyzed by size exclusion chromatography using a TSK-GEL G300
SW.sub.XL column (7.8.times.300 mm, Tosohaas, Montgomeryville, Pa.)
equilibrated in phosphate buffered saline containing 0.02%
NAN.sub.3 at a flow rate of 1.0 ml/min.
CTLA4X.sub.C120S and L104EA29YX.sub.C120S
[0176] Single chain CTLA4X.sub.C120S was prepared as previously
described (Linsley et al., (1995) J. Biol. Chem., 270:15417-15424).
Briefly, an oncostatin M CTLA4 (OMCTLA4) expression plasmid was
used as a template, the forward primer,
TABLE-US-00004 GAGGTGATAAAGCTTCACCAATGGGTGTACTGCTCACACAG
was chosen to match sequences in the vector; and the reverse
primer,
TABLE-US-00005 GTGGTGTATTGGTCTAGATCAATCAGAATCTGGGCACGGTTC
corresponded to the last seven amino acids (i.e. amino acids
118-124) in the extracellular domain of CTLA4, and contained a
restriction enzyme site, and a stop codon (TGA). The reverse primer
specified a C120S (cysteine to serine at position 120) mutation. In
particular, the nucleotide sequence GCA (nucleotides 34-36) of the
reverse primer shown above is replaced with one of the following
nucleotide sequences: AGA, GGA, TGA, CGA, ACT, or GCT. As persons
skilled in the art will understand, the nucleotide sequence GCA is
a reversed complementary sequence of the codon TGC for cysteine.
Similarly, the nucleotide sequences AGA, GGA, TGA, CGA, ACT, or GCT
are the reversed complementary sequences of the codons for serine.
Polymerase chain reaction products were digested with HindIII/XbaI
and directionally subcloned into the expression vector .pi.LN
(Bristol-Myers Squibb Company, Princeton, N.J.).
L104EA29YX.sub.C120S was prepared in an identical manner. Each
construct was verified by DNA sequencing.
Identification and Biochemical Characterization of High Avidity
Mutants
[0177] Twenty four amino acids were chosen for mutagenesis and the
resulting .about.2300 mutant proteins assayed for CD86Ig binding by
surface plasmon resonance (SPR; as described, supra). The
predominant effects of mutagenesis at each site are summarized in
Table II. Random mutagenesis of some amino acids in the S25-R33
apparently did not alter ligand binding. Mutagenesis of E31 and R33
and residues M97-Y102 apparently resulted in reduced ligand
binding. Mutagenesis of residues, S25, A29, and T30, K93, L96,
Y103, L104, and G105, resulted in proteins with slow "on" and/or
slow "off" rates. These results confirm previous findings that
residues in the S25-R33 region, and residues in or near M97-Y102
influence ligand binding (Peach et al., (1994) J. Exp. Med.,
180:2049-2058.
[0178] Mutagenesis of sites S25, T30, K93, L96, Y103, and G105
resulted in the identification of some mutant proteins that had
slower "off" rates from CD86Ig. However, in these instances, the
slow "off" rate was compromised by a slow "on" rate which resulted
in mutant proteins with an overall avidity for CD86Ig that was
apparently similar to that seen with wild type CTLA4Ig. In
addition, mutagenesis of K93 resulted in significant aggregation
which may have been responsible for the kinetic changes
observed.
[0179] Random mutagenesis of L104 followed by COS cell transfection
and screening by SPR of culture media samples over immobilized
CD86Ig yielded six media samples containing mutant proteins with
approximately 2-fold slower "off" rates than wild type CTLA4Ig.
When the corresponding cDNA of these mutants were sequenced, each
was found to encode a leucine to glutamic acid mutation (L104E).
Apparently, substitution of leucine 104 to aspartic acid (L104D)
did not affect CD86Ig binding.
[0180] Mutagenesis was then repeated at each site listed in Table
II, this time using L104E as the PCR template instead of wild type
CTLA4Ig, as described above. SPR analysis, again using immobilized
CD86Ig, identified six culture media samples from mutagenesis of
alanine 29 with proteins having approximately 4-fold slower "off"
rates than wild type CTLA4Ig. The two slowest were tyrosine
substitutions (L104EA29Y), two were leucine (L104EA29L), one was
tryptophan (L104EA29W), and one was threonine (L104EA29T).
Apparently, no slow "off" rate mutants were identified when alanine
29 was randomly mutated, alone, in wild type CTLA4Ig.
[0181] The relative molecular mass and state of aggregation of
purified L104E and L104EA29YIg was assessed by SDS-PAGE and size
exclusion chromatography. L104EA29YIg (.about.1 .mu.g; lane 3) and
L104EIg (.about.1 .mu.g; lane 2) apparently had the same
electrophoretic mobility as CTLA4Ig (.about.1 .mu.g; lane 1) under
reducing (.about.50 kDa; +.beta.ME; plus 2-mercaptoethanol) and
non-reducing (.about.100 kDa; -.beta.ME) conditions (FIG. 10A).
Size exclusion chromatography demonstrated that L104EA29YIg (FIG.
10C) apparently had the same mobility as dimeric CTLA4Ig (FIG.
10B). The major peaks represent protein dimer while the faster
eluting minor peak in FIG. 10B represents higher molecular weight
aggregates. Approximately 5.0% of CTLA4Ig was present as higher
molecular weight aggregates but there was no evidence of
aggregation of L104EA29YIg or L104EIg. Therefore, the stronger
binding to CD86Ig seen with L104EIg and L104EA29YIg could not be
attributed to aggregation induced by mutagenesis.
Equilibrium and Kinetic Binding Analysis
[0182] Equilibrium and kinetic binding analysis was performed on
protein A purified CTLA4Ig, L104EIg, and L104EA29YIg using surface
plasmon resonance (SPR). The results are shown in Table I.
TABLE-US-00006 TABLE I Equilibrium and Apparent Kinetic Constants
Immobilized Protein Analyte k.sub.on (.times.10.sup.5) M.sup.-1
S.sup.-1 k.sub.off (.times.10.sup.-3) S.sup.-1 K.sub.d nM CD80Ig
CTLA4Ig 3.44 .+-. 0.29 2.21 .+-. 0.18 6.51 .+-. 1.08 CD80Ig L104EIg
3.02 .+-. 0.05 1.35 .+-. 0.08 4.47 .+-. 0.36 CD80Ig L104EA29YIg
2.96 .+-. 0.20 1.08 .+-. 0.05 3.66 .+-. 0.41 CD80Ig
CTLA4X.sub.C120S 12.0 .+-. 1.0 230 .+-. 10 195 .+-. 25 CD80Ig
L104EA29YX.sub.C120S 8.3 .+-. 0.26 71 .+-. 5 85.0 .+-. 2.5 CD86Ig
CTLA4Ig 5.95 .+-. 0.57 8.16 .+-. 0.52 13.9 .+-. 2.27 CD86Ig L104EIg
7.03 .+-. 0.22 4.26 .+-. 0.11 6.06 .+-. 0.05 CD86Ig L104EA29YIg
6.42 .+-. 0.40 2.06 .+-. 0.03 3.21 .+-. 0.23 CD86Ig
CTLA4X.sub.C120S 16.5 .+-. 0.5 840 .+-. 55 511 .+-. 17 CD86Ig
L104EA29YX.sub.C120S 11.4 .+-. 1.6 300 .+-. 10 267 .+-. 29 (values
are means .+-. standard deviation from three different
experiments)
[0183] Observed equilibrium dissociation constants (k.sub.d; Table
I) were calculated from binding curves generated over a range of
concentrations (5.0-200 nM). L104EA29YIg binds more strongly to
CD86Ig than does L104EIg or CTLA4Ig. The lower K.sub.d of
L104EA29YIg (3.21 nM) than L104EIg (6.06 nM) or CTLA4Ig (13.9 nM)
indicates higher binding avidity of L104EA29YIg to CD86Ig. The
lower K.sub.d of L104EA29YIg (3.66 nM) than L104EIg (4.47 nM) or
CTLA4Ig (6.51 nM) indicates higher binding avidity of L104EA29YIg
to CD80Ig.
[0184] Kinetic binding analysis revealed that the comparative "on"
rates for CTLA4Ig, L104EIg, and L104EA29YIg binding to CD80 were
similar, as were the "on" rates for CD86Ig (Table I). However,
"off" rates for these molecules were not equivalent (Table I).
Compared to CTLA4Ig, L104EA29YIg had approximately 2-fold slower
"off" rate from CD80Ig, and approximately 4-fold slower "off" rate
from CD86Ig. L104E had "off" rates intermediate between L104EA29YIg
and CTLA4Ig. Since the introduction of these mutations did not
significantly affect "on" rates, the increase in avidity for CD80Ig
and CD86Ig observed with L104EA29YIg was likely primarily due to a
decrease in "off" rates.
[0185] To determine whether the increase in avidity of L104EA29YIg
for CD86Ig and CD80Ig was due to the mutations affecting the way
each monomer associated as a dimer, or whether there were avidity
enhancing structural changes introduced into each monomer, single
chain constructs of CTLA4 and L104EA29Y extracellular domains were
prepared following mutagenesis of cysteine 120 to serine as
described supra, and by Linsley et al., (1995) J. Biol. Chem.,
270:15417-15424. The purified proteins CTLA4X.sub.C120S and
L104EA29YX.sub.C120S were shown to be monomeric by gel permeation
chromatography (Linsley et al., (1995), supra), before their ligand
binding properties were analyzed by SPR. Results showed that
binding affinity of both monomeric proteins for CD86Ig was
approximately 35-80-fold less than that seen for their respective
dimers (Table I). This supports previously published data
establishing that dimerization of CTLA4 was required for high
avidity ligand binding (Greene et al., (1996) J. Biol. Chem.,
271:26762-26771).
[0186] L104EA29YX.sub.C120S bound with approximately 2-fold higher
affinity than CTLA4X.sub.C120S to both CD80Ig and CD86Ig. The
increased affinity was due to approximately 3-fold slower rate of
dissociation from both ligands. Therefore, stronger ligand binding
by L104EA29Y was most likely due to avidity enhancing structural
changes that had been introduced into each monomeric chain rather
than alterations in which the molecule dimerized.
Location and Structural Analysis of Avidity Enhancing Mutations
[0187] The solution structure of the extracellular IgV-like domain
of CTLA4 has recently been determined by NMR spectroscopy (Metzler
et al., (1997) Nature Struct. Biol., 4:527-531. This allowed
accurate location of leucine 104 and alanine 29 in the three
dimensional fold (FIG. 11A-B). Leucine 104 is situated near the
highly conserved MYPPPY amino acid sequence. Alanine 29 is situated
near the C-terminal end of the S25-R33 region, which is spatially
adjacent to the MYPPPY region. While there is significant
interaction between residues at the base of these two regions,
there is apparently no direct interaction between L104 and A29
although they both comprise part of a contiguous hydrophobic core
in the protein. The structural consequences of the two avidity
enhancing mutants were assessed by modeling. The A29Y mutation can
be easily accommodated in the cleft between the S25-R33 region and
the MYPPPY region, and may serve to stabilize the conformation of
the MYPPPY region. In wild type CTLA4, L104 forms extensive
hydrophobic interactions with L96 and V94 near the MYPPPY region.
It is highly unlikely that the glutamic acid mutation adopts a
conformation similar to that of L104 for two reasons. First, there
is insufficient space to accommodate the longer glutamic acid side
chain in the structure without significant perturbation to the
S25-R33 region. Second, the energetic costs of burying the negative
charge of the glutamic acid side chain in the hydrophobic region
would be large. Instead, modeling studies predict that the glutamic
acid side chain flips out on to the surface where its charge can be
stabilized by solvation. Such a conformational change can easily be
accommodated by G105, with minimal distortion to other residues in
the regions.
Binding of High Avidity Mutants to CHO Cells Expressing CD80 or
CD86
[0188] FACS analysis (FIG. 2) of CTLA4Ig and mutant molecules
binding to stably transfected CD80+ and CD86+CHO cells was
performed as described herein. CD80-positive and CD86-positive CHO
cells were incubated with increasing concentrations of CTLA4Ig,
L104EA29YIg, or L104EIg, and then washed. Bound immunoglobulin
fusion protein was detected using fluorescein
isothiocyanate-conjugated goat anti-human immunoglobulin.
[0189] As shown in FIG. 2, CD80-positive or CD86-positive CHO cells
(1.5.times.10.sup.5) were incubated with the indicated
concentrations of CTLA4Ig (closed squares), L104EA29YIg (circles),
or L104EIg (triangles) for 2 hr. at 23.degree. C., washed, and
incubated with fluorescein isothiocyanate-conjugated goat
anti-human immunoglobulin antibody. Binding on a total of 5,000
viable cells was analyzed (single determination) on a FACScan, and
mean fluorescence intensity (MFI) was determined from data
histograms using PC-LYSYS. Data were corrected for background
fluorescence measured on cells incubated with second step reagent
only (MFI=7). Control L6 mab (80 .mu.g/ml) gave MFI<30. These
results are representative of four independent experiments.
[0190] Binding of L104EA29YIg, L104EIg, and CTLA4Ig to human
CD80-transfected CHO cells is approximately equivalent (FIG. 2A).
L104EA29YIg and L104EIg bind more strongly to CHO cells stably
transfected with human CD86 than does CTLA4Ig (FIG. 2B).
Functional Assays
[0191] Human CD4-positive T cells were isolated by immunomagnetic
negative selection (Linsley et al., (1992) J. Exp. Med.
176:1595-1604). Isolated CD4-positive T cells were stimulated with
phorbal myristate acetate (PMA) plus CD80-positive or CD86-positive
CHO cells in the presence of titrating concentrations of inhibitor.
CD4-positive T cells (8-10.times.10.sup.4/well) were cultured in
the presence of 1 nM PMA with or without irradiated CHO cell
stimulators. Proliferative responses were measured by the addition
of 1 .mu.Ci/well of [3H]thymidine during the final 7 hours of a 72
hour culture. Inhibition of PMA plus CD80-positive CHO, or
CD86-positive CHO, stimulated T cells by L104EA29YIg and CTLA4Ig
was performed. The results are shown in FIG. 3. L104EA29YIg
inhibits proliferation of CD80-positive PMA treated CHO cells more
than CTLA4Ig (FIG. 3A). L104EA29YIg is also more effective than
CTLA4Ig at inhibiting proliferation of CD86-positive PMA treated
CHO cells (FIG. 3B). Therefore, L104EA29YIg is a more potent
inhibitor of both CD80- and CD86-mediated costimulation of T
cells.
[0192] FIG. 4 shows inhibition by L104EA29YIg and CTLA4Ig of
allostimulated human T cells prepared above, and further
allostimulated with a human B lymphoblastoid cell line (LCL) called
PM that expressed CD80 and CD86 (T cells at 3.0.times.10.sup.4/well
and PM at 8.0.times.10.sup.3/well). Primary allostimulation
occurred for 6 days, then the cells were pulsed with
.sup.3H-thymidine for 7 hours, before incorporation of radiolabel
was determined.
[0193] Secondary allostimulation was performed as follows. Seven
day primary allostimulated T cells were harvested over lymphocyte
separation medium (LSM) (ICN, Aurora, Ohio) and rested for 24
hours. T cells were then restimulated (secondary), in the presence
of titrating amounts of CTLA4Ig or L104EA29YIg, by adding PM in the
same ratio as above. Stimulation occurred for 3 days, then the
cells were pulsed with radiolabel and harvested as above. The
effect of L104EA29YIg on primary allostimulated T cells is shown in
FIG. 4A. The effect of L104EA29YIg on secondary allostimulated T
cells is shown in FIG. 4B. L104EA29YIg inhibits both primary and
secondary T cell proliferative responses better than CTLA4Ig.
[0194] To measure cytokine production (FIG. 5), duplicate secondary
allostimulation plates were set up. After 3 days, culture media was
assayed using ELISA kits (Biosource, Camarillo, Calif.) using
conditions recommended by the manufacturer. L104EA29YIg was found
to be more potent than CTLA4Ig at blocking T cell IL-2, IL-4, and
.gamma.-IFN cytokine production following a secondary allogeneic
stimulus (FIGS. 5A-C).
[0195] The effects of L104EA29YIg and CTLA4Ig on monkey mixed
lymphocyte response (MLR) are shown in FIG. 6. Peripheral blood
mononuclear cells (PBMC'S; 3.5.times.10.sup.4 cells/well from each
monkey) from 2 monkeys were purified over lymphocyte separation
medium (LSM) and mixed with 2 .mu.g/ml phytohemaglutinin (PHA). The
cells were stimulated 3 days then pulsed with radiolabel 16 hours
before harvesting. L104EA29YIg inhibited monkey T cell
proliferation better than CTLA4Ig.
TABLE-US-00007 TABLE II The effect on CD86Ig binding by mutagenesis
of CTLA4Ig at the sites listed Effects of Mutagenesis No Apparent
Slow "on" rate/slow Reduced ligand Mutagenesis Site Effect "off
rate binding S25 + P26 + G27 + K28 + A29 + T30 + E31 + R33 + K93 +
L96 + M97 + Y98 + P99 + P100 + P101 + Y102 + Y103 + L104 + G105 +
I106 + G107 + Q111 + Y113 + I115 + (The predominant effect is
indicated with a "+" sign)
Example 3
[0196] This study compared the efficacy and safety of L104EA29YIg,
described above, as a maintenance immunosuppressant with CsA over
12 months when used as part of a CNI-free combination regimen
consisting of basiliximab (Simulect.RTM.; Novartis) induction,
mycophenolate mofetil (MMF; CellCept.RTM.; Roche), and
corticosteroids in renal transplant recipients.
[0197] Adult recipients of a non-HLA-identical renal allograft from
a living or deceased donor were eligible. Subjects with a prior
renal transplant, a history of panel-reactive antibodies of
>20%, or those deemed by the investigator to be at higher risk
of acute rejection were restricted to .ltoreq.10% of the study
population. Exclusion criteria included underlying renal disease of
focal and segmental glomerulosclerosis, Type I or II
membranoproliferative glomerulonephritis, or hemolytic uremic
syndrome/thrombotic thrombocytopenic purpura; active hepatitis B or
C, or HIV; and donor age >60 or <6, donors with cardiac
death, or donor kidney cold ischemia time of >36 hours.
[0198] This was an open-label, randomized, active-controlled,
multiple-dose, multicenter study performed in the United States,
Europe and Canada. Eligible patients of either sex aged .gtoreq.18
years undergoing a renal transplant (deceased or living donor,
except when donor and recipient were HLA-identical) were randomized
to treatment in a 1:1:1 ratio with an L104EA29YIg more-intensive
(MI) treatment regimen, L104EA29YIg less-intensive (LI) treatment
regimen, or Cyclosporine A (CsA); all in combination with induction
therapy with basiliximab (Simulect.RTM.; Novartis), adjunctive
maintenance therapy with mycophenolate mofetil (MMF; CellCept.RTM.;
Roche), and corticosteroids. Both L104EA29YIg regimens included an
early phase, in which L104EA29YIg was administered at 10 mg/kg, and
a maintenance phase, in which L104EA29YIg was administered at 5
mg/kg at q4 week or q8 week intervals. Doses for each regimen were
based on body weight. These doses were dictated by the target
trough profiles shown to be effective during non-human primate
studies. These profiles necessitated doses that were higher
initially, during the period of greatest immunologic risk (Day
0-90). The early phase was longer in the MI regimen (6 vs. 3
months) and included more frequent dosing.
[0199] L104EA29YIg more intensive (MI) treatment regimen consisted
administration of 10 mg/kg on days 1, 5, 15, 29, 43, 57, 71, 85,
113, 141 and 169, followed by 5 mg/kg every 4 or 8 weeks.
L104EA29YIg less intensive (LI) treatment regimen consisted of 10
mg/kg on days 1, 15, 29, 57 and 85, followed by 5 mg/kg every 4 or
8 weeks. L104EA29YIg was administered in a 30-minute intravenous
infusion. Patients randomized to CsA received twice-daily doses
(7.+-.3 mg/kg) to achieve the pre-specified range of target serum
concentrations of 150-400 ng/ml during the first month and 150-300
ng/ml during months 2-12, which is consistent with current medical
practice. All patients received MMF 2 g daily and basiliximab 20 mg
every 4 days. A corticosteroid tapering regimen was also given
consisting of an iv bolus of methylprednisolone 500 mg on Day 1 and
250 mg on Day 2, followed by oral prednisone 100 mg on Day 3, 50 mg
on Day 4, 25 mg on Days 5-30, 22.5 mg on Days 31-44, 20 mg on Days
45-58, 17.5 mg on Days 59-72, 15 mg on Day 73-86, 12.5 mg on Days
87-100, and 10 mg on Days 101-114. After Day 114, the prednisone
dose could be decreased by 2.5 mg every other month but not to less
than 5 mg per day.
[0200] The primary objective was to demonstrate that L104EA29YIg
was not inferior to CsA in the prevention of acute rejection at 6
months. Secondary objectives included assessment of the incidence
of acute rejection (biopsy-confirmed or presumed) at 6 months and 1
year; measured glomerular filtration rate (GFR) via iohexyl
clearance at 1, 6, and 12 months; parameters of hypertension; serum
cholesterol and triglycerides; and overall safety. Other
pre-specified analyses included patient death or graft loss at 1
year; the severity of acute rejection; the incidence of
post-transplant diabetes mellitus [defined as any therapy required
for hyperglycemia for .gtoreq.4 weeks, or a hemoglobin A1C
(HbA1c)>7%, in patients not previously known to be diabetic];
calculated GFR, using the Modification of Diet in Renal Disease
(MDRD, Levey A S, Bosch J P, Lewis J P, Greene T, Rogers N, Roth D.
A more accurate method to estimate glomerular filtration rate from
serum creatinine: a new prediction equation. Modification of Diet
in Renal Disease Study Group. Ann Intern Med 1999; 130:461-470),
Jelliffe (R W. Creatinine clearance: Bedside estimate. Ann Inter
Med. 1973; 79:604-605), Cockcroft-Gault (Cockcroft D W, Gault M H.
Prediction of creatinine clearance from serum creatinine. Nephron
1976; 16:31-41), and Nankivell (Nankivell B J, Gruenewald S M,
Allen R D, Chapman J R. Predicting glomerular filtration rate after
kidney transplantation. Transplantation. 1995; 59(12):1683-1689)
formulas; pharmacokinetics and immunogenicity. Diagnosis and
treatment of acute rejection (AR) was based on the Banff 97
criteria and grade (Racusen L C, Solez K, Colvin R B, et al. The
Banff 97 working classification of renal allograft pathology.
Kidney Int 1999; 55(2):713-23.). A post-hoc analysis was conducted
of the incidence of chronic allograft nephropathy (CAN).
[0201] Diagnosis and treatment of acute rejection (AR) was based on
the Banff 97 criteria and grade (Racusen L C, Solez K, Colvin R B,
et al. The Banff 97 working classification of renal allograft
pathology. Kidney Int 1999; 55(2):713-23.). Intraoperative renal
allograft biopsies were performed to assess baseline histology.
Biopsied tissue was stained and graded according to the Banff 97
working classification of kidney transplant pathology. Biopsies
were evaluated by an independent pathologist blinded to treatment
to confirm all episodes of clinically-suspected AR prior to
treatment for AR.
[0202] Additional endpoints included: clinically suspected and
biopsy proven acute rejection (CSBPAR) at 12 months; death or graft
loss at 1 year; severity of AR episodes (measured using the Banff
97 scale); treatment failure (defined as investigator opinion;
.gtoreq.grade IIB rejection; recurrent or steroid-resistant
rejection); renal function at 1, 6 and 12 months (glomerular
filtration rates [GFRs] assessed by Iohexyl clearance) and evidence
of chronic allograft nephropathy (CAN) (interstitial fibrosis and
tubular atrophy); parameters of hypertension (diastolic blood
pressure [BP] .gtoreq.90 mm Hg and/or systolic BP.gtoreq.140 mm
Hg); serum lipids; safety, tolerability and adverse events (AEs) in
patients treated with L104EA29YIg compared with CsA-treated
patients.
[0203] For safety and tolerability assessments, AEs, laboratory
measurements (hematology, biochemistry and urine analysis) and
vital signs were recorded during regular scheduled clinic
visits.
Results
[0204] A total of 218 patients underwent renal transplantation and
were randomized to the MI group (N=74), LI group (N=71), or CsA
(N=73). Baseline demographics and clinical characteristics were
similar between the three treatment groups. A total of 164 patients
completed 1 year of treatment. Of the patients who discontinued
prior to 1 year (N=16 vs 16 vs 20; MI regimen versus LI regimen
versus CsA), the most common reasons were AEs (N=5 versus 8 vs 9)
and treatment failure (N=7 versus 5 versus 3).
[0205] The incidence of CSBPAR occurred infrequently in all
treatment groups, and there was no statistically significant
difference in the incidence of either CSBPAR or biopsy proven acute
rejection (BPAR) between treatment groups. At 6 and 12 months,
incidence of CSBPAR was 6.8%, 5.6% and 8.2% for MI, LI and CsA
treatment, respectively.
[0206] Incidence of BPAR was also similar between groups at 6 and
12 months, although BPAR was slightly higher in the LI group than
in the other two groups (18.9%, 29.6% and 17.8% for MI, LI and CsA
treatment respectively). Biopsy-proven acute rejection was more
frequent than CSBPAR in all treatment groups, and was most common
in the LI group. However, many of these events were found to occur
in patients with L104EA29YIg at below desired trough serum
concentrations.
[0207] No statistically significant difference between treatment
groups was seen in the severity of AR; however, numbers were small
and did not result in graft loss.
[0208] This study was unblinded to study medication in order to
permit standard of care with respect to CsA, which probably
contributed to the increased number of biopsies taken in the
L104EA29YIg groups (N=345) compared with the CsA group (N=144).
Although this is not unexpected for a study designed in this way,
it could have increased the rate of diagnosis of renal histological
abnormalities in the L104EA29YIg treatment groups.
[0209] Death and/or graft loss was infrequent in all treatment
groups, with 1 death reported in the MI group, 4 in the CsA group
and none in the LI group. Most graft losses were not caused by
immunologic events and only 3 grafts were lost in the MI and CsA
groups versus 1 in the LI group.
[0210] Significant improvements in renal function were seen with
L104EA29YIg-based treatment compared to CsA-based
immunosuppression. Iohexyl clearance was greater with L104EA29YIg
treatment at all time-points, with a mean improvement of 11
ml/min/1.73 m.sup.2 (.about.20%) compared with CsA at 12
months.
[0211] At 12 months, chronic allograft nephropathy (CAN) was
between 30 and 50% less common, in relative terms, in
L104EA29YIg--than CsA-treated patients. Rates of new or worsening
CAN at 12 months were 29%, 19% and 44% for MI, LI and CsA groups,
respectively.
[0212] At 1 year, mean systolic blood pressure was 3-4 mmHg higher
in patients treated with CsA (133 mmHg) versus patients in the MI
(130 mmHg) and LI (129 mmHg) treatment groups. This was despite
lower use of anti-hypertensive medication in the L104EA29YIg groups
(MI: 87.5%; LI 84.1%: CsA 92.2%). Total serum cholesterol was
slightly lower with L104EA29YIg (MI: 198 mg/dL; LI: 201 mg/dL)
versus CsA-(212 mg/dL) treated patients although lipid-lowering
medication use was also lower with L104EA29YIg (MI: 36.1%; LI:
31.9%; CsA: 53.1%).
[0213] Four (5.5%) patients died in the CsA group compared with 1
in the L104EA29YIg treatment groups. Rates of adverse events (AEs)
were comparable between treatment groups; however, related AEs were
significantly lower following L104EA29YIg treatment than CsA
treatment. Intravenous administration of L104EA29YIg was well
tolerated with no infusion reactions. L104EA29YIg-treated patients
did not exhibit typical CsA-related adverse events, such as anemia,
leucopenia, hirsutism, tremor and gingival hyperplasia.
L104EA29YIg-based therapy was not associated with any increased
risk of infections or malignancies compared with CsA-based
therapy.
Conclusion
[0214] This 12-month study demonstrates that L104EA29YIg-based
maintenance therapy confers equivalent efficacy in preventing AR
and similar patient and graft survival compared with CsA. In
addition, L104EA29YIg demonstrated significant improvements in
renal function and reductions in CAN compared with CsA-based
maintenance immunosuppression. L104EA29YIg was safe and well
tolerated and was not associated with typical CNI-related
toxicities.
[0215] Rates of CSBPAR and BPAR were similar between the three
treatment groups demonstrating that the low AR rates observed with
CsA-based therapy are also achieved with L104EA29YIg. The majority
of BPARs were classified as sub-clinical, suggesting that renal
function was not impaired. The numerically lower rate of AR in the
MI group, compared with the LI group, suggests a possible
dose-dependent response with L104EA29YIg. More frequent biopsies in
the L104EA29YIg groups could potentially have led to over-diagnosis
of both acute and chronic rejection in these groups, suggesting
that the benefits of L104EA29YIg therapy may be understated in this
study.
[0216] The majority of BPAR events occurred within the first three
post-transplant months, which is not unexpected since others have
shown that higher doses of immunosuppressants are required during
the early post-transplantation period (Wiecek A, Nowicki M, Kokot
F, Ritz E. Acute failure of the transplanted
kidney--pathophysiology, diagnosis and prevention. Ann Transplant
1996; 1(4):5-9 and Bennett W M. Posttransplant acute renal failure.
Ren Fail 1997; 19(2):225-6). Since the majority of these events
occurred at below desired trough values, consideration should be
given to altering the regimen in the first month of treatment,
prior to reaching a steady state. The majority of the BPARs seen
during the maintenance phase occurred at very low or undetectable
levels of L104EA29YIg, suggesting that the incidence of AR during
those periods was related to insufficient immunosuppression, which
may be avoided by alterations in the dose regimen.
[0217] This study demonstrates that L104EA29YIg is associated with
similar overall AE rates compared with CsA, with fewer AEs related
to study drug. No real differences in the number of viral-related
AEs were identified between the three treatment groups.
[0218] In the presence of low AR rates, the new goal of maintenance
immunosuppression is reduction in long-term health complications,
including hypertension, hyperlipidemia, drug toxicity, and the
prevention of scarring. As in autoimmune diseases, a new generation
of immunoselective maintenance immunosuppressive agents is
emerging. Inhibition of T-cell co-stimulation via immunoselective
co-stimulation blockade with L104EA29YIg represents a new paradigm,
offering the promise of more selective maintenance
immunosuppression, reduced toxicities and improved long-term
outcomes in renal transplantation.
Example 4
[0219] There exists substantial unmet medical need for new
therapies in renal transplantation that can provide short-term
subject and graft survival comparable to the CNIs without their
long-term nephrotoxic, cardiovascular, and metabolic effects. The
need is particularly great among recipients of ECD define renal
allografts, whose long-term subject and graft survival rates are
distinctly below those of recipients of allografts from donors
meeting standard eligibility criteria. L104EA29YIg, an
immunosuppressive agent with a novel mechanism of action, is a
promising non-nephrotoxic candidate for use in renal transplant
recipients of ECD allografts. Because L104EA29YIg can be
administered at the time of engraftment rather than in a delayed
fashion, as is frequently necessary with CNIs--especially in those
allografts with initial impaired renal function--it affords
immunosuppression in a timely manner and without the need for
polyclonal antilymphocyte preparations. This may translate into
comparable rates of acute rejection with a favorable safety
profile. As L104EA29YIg is not anticipated to be nephrotoxic,
additional benefits should be seen with respect to allograft
structure (ie, CAN) and function (ie, GFR). Finally, unlike CNIs,
the targeted mechanism of action of L104EA29YIg should provide
immunosuppression without adversely affecting the
cardiovascular/metabolic profile. An overall benefit-risk
assessment for the use of L104EA29YIg in this subject population is
provided below.
[0220] Two dose regimens (as described in Example 3, with a minor
modification to the LI regimen and using the every 4-week
maintenance infusion schedule) will be studied.
Primary Objectives
[0221] 1.) Evaluate the effects of L104EA29YIg, relative to CsA, on
the composite of subject and graft survival at 12 months.
[0222] 2.) Evaluate the effects of L104EA29YIg, relative to CsA, on
the composite of measured GFR<60 mL/min/1.73 m.sup.2 at Month 12
or a decrease in measured GFR.gtoreq.10 mL/min/1.73 m.sup.2 from
Month 3 to Month 12.
Secondary Objectives
[0223] 1.) Evaluate the effects of L104EA29YIg, relative to CsA, on
measured GFR at 12 months.
[0224] 2.) Evaluate the effects of L104EA29YIg, relative to CsA, on
biopsy-proven CAN by 12 months.
[0225] 3) Assess the effects of L104EA29YIg, relative to CsA, on
measured GFR at 3 months, and change from baseline (3 months) to 12
months.
[0226] 4.) Assess the effects of L104EA29YIg, relative to CsA, on
the proportion of subjects with a measured GFR<30 mL/min/1.73
m.sup.2 at 12 months.
[0227] 5) Assess the effects of L104EA29YIg, relative to CsA, on
calculated GFR at 3, 12, 24, and 36 months, and change from
baseline (3 months) to 12, 24, and 36 months.
[0228] 6.) Assess the effects of L104EA29YIg, relative to CsA, on
PTDM at 12, 24, and 36 months.
[0229] 7.) Assess the effects of L104EA29YIg, relative to CsA, on
measures of hypertension at 12, 24, and 36 months, including SBP
and DBP, incidence and prevalence of hypertension and controlled
hypertension, and intensity of treatment regimen.
[0230] 8.) Assess the effects of L104EA29YIg, relative to CsA, on
measures of dyslipidemia, at 12, 24, and 36 months, including serum
total, non-HDL, low-density lipoprotein (LDL), and HDL cholesterol,
and TGs, incidence and prevalence of dyslipidemia and controlled
dyslipidemia, and intensity of treatment regimen.
[0231] 9.) Evaluate the effects of L104EA29YIg, relative to CsA, on
subject and graft survival at 24 and 36 months.
[0232] 10.) Assess the effects of L104EA29YIg, relative to CsA, on
measures of acute rejection at 6 months, including the incidence
and severity of acute rejection, the use of polyclonal
antilymphocyte preparations for impaired renal function and
anticipated DGF, the initial use of lymphocyte-depleting therapy
for treatment of acute rejection, the incidence of
steroid-resistant acute rejection, the incidence of complete
recovery (SCr returning to baseline) following acute rejection, the
incidence of subclinical rejection, and the incidence of all
treated acute rejection episodes regardless of histological
findings.
[0233] 11) Evaluate the effects of L104EA29YIg, relative to CsA, on
QoL.
[0234] 12.) Assess the overall safety of L104EA29YIg, relative to
CsA.
Tertiary Objectives
[0235] 1) Assess the effects of L104EA29YIg, relative to CsA, on
the slope and intercept of calculated GFR from baseline (3 months)
to 12, 24, and 36 months.
[0236] 2) Assess the effects of L104EA29YIg, relative to CsA, on
the proportion of subjects with a measured GFR<45 mL/min/1.73
m.sup.2 at 12 months.
[0237] 3) Assess the effects of L104EA29YIg, relative to CsA, on
the proportion of subjects with <75 mL/min/1.73 m.sup.2
calculated GFR at Month 12 and subjects with a decrease in
calculated GFR from Month 3 to Month 12 of at least 15 mL/min/1.73
m.sup.2.
[0238] 4) Assess the effects of L104EA29YIg, relative to CsA, on
the incidence of DGF.
[0239] 5.) Assess the effects of L104EA29YIg, relative to CsA, on
measures of acute rejection at 12, 24, and 36 months, including the
incidence and severity of acute rejection, the use of polyclonal
antilymphocyte preparations for impaired renal function and
anticipated DGF, the initial use of lymphocyte-depleting therapy
for treatment of acute rejection, and the incidence of
steroid-resistant acute rejection, the incidence of complete
recovery (SCr returning to baseline) following acute rejection, the
incidence of subclinical rejection, and the incidence of all
treated acute rejection episodes regardless of histological
findings.
[0240] 6) Assess the effects of L104EA29YIg, relative to CsA, on a
composite cardiovascular disease endpoint (adjudicated
cardiovascular death, myocardial infarction, ischemic stroke,
non-elective hospitalization for cardiovascular cause, and
percutaneous coronary intervention) at 12, 24, and 36 months.
[0241] 7) Assess the effects of L104EA29YIg, relative to CsA, on a
composite cardiorenal disease endpoint (death, graft loss,
non-fatal myocardial infarction, and stroke) at 12, 24, and 36
months.
[0242] 8.) Assess the effects of L104EA29YIg, relative to CsA, on
the Framingham Risk Score at 12, 24, and 36 months.
[0243] 9.) Assess the effects of L104EA29YIg, relative to CsA, on
incidence of discontinuation of study drug.
[0244] 10.) Assess the effects of L104EA29YIg, relative to CsA, on
anti-donor human leukocyte antigen (HLA) antibodies.
[0245] 11) Assess the effects of L104EA29YIg, relative to CsA, on
C4d positivity in biopsy specimens.
Study Design
[0246] The duration of the study is 3 years with a subsequent
8-week follow-up period for safety evaluations. At the end of the
3-year treatment period, subjects may be eligible for a long-term
extension study.
[0247] This is a randomized, partially-blinded, active-controlled,
parallel-group study. All subjects will receive a kidney from a
donor with extended criteria as defined below. These criteria are
based in part on those issued by the United Network of Organ
Sharing (UNOS); they also include other features widely used to
identify potentially compromised organs, such as those from donors
with cardiac death (DCD, non-heart beating) or with prolonged cold
ischemia time (CIT).
[0248] Approximately 540 subjects will be randomized in a 1:1:1
ratio to treatment with either L104EA29YIg (MI regimen),
L104EA29YIg (LI regimen), or CsA. All subjects will also receive
induction with basiliximab and a background maintenance
immunosuppressive regimen of MMF and corticosteroids. Subjects
randomized to the MI regimen will receive i.v. L104EA29YIg (10
mg/kg) on Days 1 and 5, then every 2 weeks through Month 3 (Weeks
2, 4, 6, 8, 10, and 12), and then every 4 weeks through 6 months
(Weeks 16, 20, and 24). After 6 months, subjects in the MI
treatment group will receive the maintenance dose of L104EA29YIg 5
mg/kg administered every 4 weeks until completion of the trial at
36 months. Subjects randomized to the LI regimen will receive i.v.
L104EA29YIg (10 mg/kg) on Days 1 and 5, and then every 2 weeks
through Month 1 (Weeks 2 and 4), and every 4 weeks through Month 3
(Weeks 8 and 12). After 3 months, subjects in the LI treatment
group will receive the maintenance dose of L104EA29YIg 5 mg/kg
administered every 4 weeks until completion of the trial at 36
months.
[0249] Blinding between the LI and MI groups will be preserved with
the use of placebo infusions in the LI treatment group on Weeks 6
and 10. Subjects randomized to CsA will receive doses twice daily
that are designed to achieve a specified trough serum concentration
range consistent with current medical practice.
[0250] The use of polyclonal antilymphocyte preparations
(Thymoglobulin or ATGAM) is permitted--but not required--for
subjects randomized to CsA who experience impaired renal allograft
function and anticipated DGF. These agents are widely utilized in
this capacity to afford immunosuppression until graft function
recovers for administration of CsA. The decision to use and dose a
polyclonal antilymphocyte preparation in this clinical setting is
at the investigator's discretion within the protocol guidelines.
The safety and efficacy of L104EA29YIg will be assessed at 1, 2,
and 3 years.
Primary Outcome Measures
[0251] Each L104EA29YIg-based regimen will be compared to the
CsA-based regimen on the following primary efficacy outcome
measures: (1) the composite of subject and graft survival at 12
months; (2) the composite of measured GFR<60 mL/min/1.73 m.sup.2
at Month 12 or a decrease in measured GFR.gtoreq.10 mL/min/1.73
m.sup.2 from Month 3 to Month 12. The intent is to demonstrate
non-inferiority for death and graft loss and superiority for renal
function. The endpoint of subject and graft survival was selected
since these measures are the most important clinical outcomes for
allograft recipients. Although allograft loss can be prevented by
effective immunosuppressive therapy, the same therapy may increase
the risk of death from infection, PTLD, malignancy, nephrotoxicity,
or cardiovascular disease. Thus, it is appropriate to examine the
composite endpoint of subject and graft survival as a summary
measure of the net benefit of immunosuppressive therapy in
allograft recipients. This composite endpoint has the further
advantage of being assessable in all subjects without bias due to
missing data or subject misclassification.
[0252] Renal function as an endpoint was selected since the
relationship between post-transplant renal function and long-term
renal outcome has been repeatedly demonstrated in various settings.
The association is present whether renal function is measured a few
days after transplant, at the time of discharge from the hospital,
or at 6 and 12 months following transplant. It has been observed in
recipients of kidneys from living and cadaveric donors, in
recipients of kidneys from younger and older cadaveric donors, in
second transplant recipients, and in adult and pediatric
recipients.
[0253] Results from multicenter studies confirm the importance of
SCr for predicting long-term graft survival. The relationship
between renal function and long-term prognosis is strong and
reproducible, but not strictly linear. In an analysis of adult
renal transplant recipients, examination of the relationship
between SCr at 1 year and projected median graft half-life revealed
a pronounced inflection point at SCr>1.5 mg/dL. Similarly,
examination of the relationship between change in SCr from 6 months
to 1 year (.DELTA. SCr) and projected median graft half-life
revealed a pronounced inflection point at .DELTA. SCr.gtoreq.0.3
mg/dL. Thus, both the absolute level of renal function at 1 year
and the change in renal function from 6 months (or a similar
stable, early post-transplant time point) to 1 year is suitable for
use as outcome measures. The presence of non-linearity in the
relationship of renal function to long-term outcome suggests that
categorical measures of renal function would be of greater clinical
relevance than dimensional ones. Threshold values of >1.5 mg/dL
at 1 year for renal function and change in SCr of .gtoreq.0.3 mg/dL
from Month 6 to Year 1 appear appropriate.
[0254] In the studies referenced above, the prognostic importance
of renal function was demonstrated using SCr as a marker. These
studies were in general too large to use direct measures of
glomerular filtration. The limitations of SCr as a marker of renal
function are well known. SCr levels reflect primarily the balance
between renal excretion of creatinine and endogenous generation of
creatinine. The latter can be significantly affected by variations
in muscle mass, infection, inflammation, and steroid use, which are
all common in the transplant population. Moreover, the renal
excretion of creatinine can occur by 2 routes--glomerular
filtration and tubular secretion. The impact of loss of glomerular
filtration on SCr is commonly masked by compensatory increases in
tubular secretion, and the utility of increased SCr as a marker of
renal impairment is thereby reduced. It has been estimated that 40%
of subjects with reduced GFR will have normal or low SCr. Numerous
formulae have been developed that seek to improve the correlation
between SCr and GFR by accounting for the effect of demographic and
biometric factors. The level of agreement between GFR estimated
from various formulas and true GFR measured by inulin clearance was
studied in 294 transplant recipients with stable renal function.
The proportion of predicted GFR values differing from measured
inulin clearance by at least 10 mL/min/1.73 m.sup.2 ranged from 34%
for the Jelliffe formula to 53% for the Nankivell formula. The
formula proposed by Levey et al will be used to calculate GFR in
this study. This formula has been shown to predict GFR more
accurately in the transplant population, having the best
correlation between predicted and measured value than other
formulae, such as Nankivell. Given the substantial difference
between true GFR and calculated GFR, clearance of a true glomerular
filtration marker will be used to assess the primary endpoint of
renal function (Appendix 1). A GFR of 60 mL/min/1.73 m.sup.2, or
change in GFR of at least 10 mL/min/1.73 m.sup.2, will be used as
the approximate equals of the threshold values of SCr of 1.5 mg/dL
or change in SCr of at least 0.3 mg/dL established in large
epidemiological studies. The change component of the composite
endpoint will be assessed from Months 3 to 12, since
post-transplant renal function is largely stable by Month 3.
Other Outcome Measures
[0255] The key secondary objectives are to evaluate the effects of
L104EA29YIg, relative to CsA, on measured GFR at 12 months and on
biopsy-proven CAN at 12 months. These endpoints are segregated from
other secondary endpoints to emphasize their importance in the
evaluation of L104EA29YIg. As discussed above, the functional
nephron mass and renal reserve in ECD kidneys are likely to be
reduced at the time of transplantation due to donor characteristics
(e.g., older age, cardiovascular co-morbidities, procurement
procedures, and CIT) with resultant subject and graft survival
rates that are well below that observed with standard criteria
donor organs. Since renal function is potentially diminished at
time of engraftment, it is possible that a substantial proportion
of subjects may meet criteria for the co-primary renal function
endpoint at the time of study entry or determination of baseline
renal allograft function. Accordingly, a key secondary objective of
the protocol is to evaluate the effects of L104EA29YIg, relative to
CsA, in the difference in measured GFR at 12 months. This key
secondary endpoint allows for discernment of the effects of
L104EA29YIg, as compared with CsA, irrespective of preexisting
donor variability in this ECD population. It also contributes to
the evaluation of renal function in total, and strengthens further
the conclusion that L104EA29YIg provides a significant medical
benefit in renal transplant recipients. The remaining key secondary
objective is the biopsy-proven CAN by 12 months. CAN is second only
to death with a functioning graft as the leading cause of late
renal allograft loss. Paradoxically, CNIs are thought to contribute
to CAN through direct (ie, direct nephrotoxic effects) and indirect
pathways (ie, adverse cardiovascular and metabolic effects). Due to
its specific mechanism of action, L104EA29YIg is unlikely to be
either directly nephrotoxic or adversely alter cardiovascular and
metabolic parameters.
[0256] In the Example above, favorable effects were seen in the
reduced incidence of CAN among L104EA29YIg-treated subjects. In the
current study, establishing a decrease in the incidence of CAN, in
conjunction with an improvement in renal function, would strengthen
the conclusion that L104EA29YIg provides a significant medical
benefit in renal transplant recipients. The efficacy of L104EA29YIg
in the prevention of acute rejection will be assessed by a variety
of outcome measures. These include its incidence, severity,
responsiveness to therapy, and outcome. The interpretation of these
measures, however, is complicated by intrinsic differences in
L104EA29YIg and CsA. L104EA29YIg is administered at the time of
transplant, while CsA is initiated once there is evidence of
incipient renal function. It is anticipated that a some subjects
randomized to CsA in this study will receive a polyclonal
antilymphocyte preparation to provide immunosuppressive coverage if
initial renal function is impaired and DGF is anticipated. This
therapeutic action may prevent or mask the development of acute
rejection in CsA-treated subjects and render the subject
unevaluable for the outcome measures of acute rejection. Because it
is unnecessary to take similar action in subjects randomized to
L104EA29YIg--who are treated from the time of transplant--the
comparative assessment of acute rejection is unequal. In order to
more accurately assess the efficacy of L104EA29YIg in the
prevention of acute rejection, the use of polyclonal lymphocyte
preparations in this capacity will also be reported in conjunction
with other measures of acute rejection.
Study Population
[0257] The study population includes recipients of renal allografts
that are potentially suboptimal due to donor characteristics,
procurement procedure, CIT, or other factors. The specific
eligibility criteria are based upon the `expanded criteria` for
organ donation issued by UNOS. Recipients of kidneys from donors
with prolonged CIT or from DCDs, will also be eligible. In general,
immunological criteria will not play a major role in subject
selection. Subjects at varying levels of immunological risk are
eligible. The study will, however, exclude subjects of greatest
immunological risk (positive cross-match, panel reactive antibodies
[PRA] of .gtoreq.30%, or those previously transplanted). These
subjects may require therapy to reduce their antibody load, such as
plasmapheresis, which is beyond the scope of this protocol.
Subjects will be enrolled at approximately 90 sites globally.
Primary Efficacy Outcome Measures
[0258] 1.) Evaluate the effects of L104EA29YIg, relative to CsA, on
the composite of subject and graft survival at 12 months.
[0259] 2.) Evaluate the effects of L104EA29YIg, relative to CsA, on
the composite of measured GFR<60 mL/min/1.73 m.sup.2 at Month 12
or a decrease in measured GFR.gtoreq.10 mL/min/1.73 m.sup.2 from
Month 3 to Month 12.
Secondary Efficacy Outcome Measures
[0260] 1) Evaluate the effects of L104EA29YIg, relative to CsA, on
measured GFR at 12 months.
[0261] 2) Evaluate the effects of L104EA29YIg, relative to CsA, on
biopsy-proven CAN by 12 months.
[0262] 3) Assess the effects of L104EA29YIg, relative to CsA, on
measured GFR at 3 months, and change from baseline (3 months) to 12
months.
[0263] 4) Assess the effects of L104EA29YIg, relative to CsA, on
the proportion of subjects with a measured GFR<30 mL/min/1.73
m.sup.2 at 12 months.
[0264] 5) Assess the effects of L104EA29YIg, relative to CsA, on
calculated GFR at 3, 12, 24, and 36 months, and change from
baseline (3 months) to 12, 24, and 36 months.
[0265] 6) Assess the effects of L104EA29YIg, relative to CsA, on
PTDM at 12, 24, and 36 months.
[0266] 7) Assess the effects of L104EA29YIg, relative to CsA, on
measures of hypertension at 12, 24, and 36 months, including SBP
and DBP, incidence and prevalence of hypertension and controlled
hypertension, and intensity of treatment regimen.
[0267] 8) Assess the effects of L104EA29YIg, relative to CsA, on
measures of dyslipidemia, at 12, 24, and 36 months, including serum
total, non-HDL, LDL, and HDL cholesterol, and TGs, incidence and
prevalence of dyslipidemia and controlled dyslipidemia, and
intensity of treatment regimen.
[0268] 9) Evaluate the effects of L104EA29YIg, relative to CsA, on
subject and graft survival at 24 and 36 months.
[0269] 10) Assess the effects of L104EA29YIg, relative to CsA, on
measures of acute rejection at 6 months, including the incidence
and severity of acute rejection, the use of polyclonal
antilymphocyte preparations for impaired renal function and
anticipated DGF, the initial use of lymphocyte-depleting therapy
for treatment of acute rejection, the incidence of
steroid-resistant acute rejection, the incidence of complete
recovery (SCr returning to baseline) following acute rejection, the
incidence of subclinical rejection, and the incidence of all
treated acute rejection episodes regardless of histological
findings.
[0270] 11) Evaluate the effects of L104EA29YIg, relative to CsA, on
QoL 10.) Assess the overall safety of L104EA29YIg, relative to
CsA.
Tertiary Outcome Measures
[0271] 1.) Assess the effects of L104EA29YIg, relative to CsA, on
the slope and intercept of calculated GFR from baseline (3 months)
to 12, 24, and 36 months.
[0272] 2) Assess the effects of L104EA29YIg, relative to CsA, on
the proportion of subjects with a measured GFR<45 mL/min/1.73
m.sup.2 at 12 months.
[0273] 3) Assess the effects of L104EA29YIg, relative to CsA, on
the proportion of subjects with <75 mL/min/1.73 m.sup.2
calculated GFR at Month 12 and subjects with a decrease in
calculated GFR from Month 3 to Month 12 of at least 15 mL/min/1.73
m.sup.2.
[0274] 4) Assess the effects of L104EA29YIg, relative to CsA, on
the incidence of DGF.
[0275] 5) Assess the effects of L104EA29YIg, relative to CsA, on
measures of acute rejection at 12, 24, and 36 months, including the
incidence and severity of acute rejection, the use of polyclonal
antilymphocyte preparations for impaired renal function and
anticipated DGF, the initial use of lymphocyte-depleting therapy
for treatment of acute rejection, and the incidence of
steroid-resistant acute rejection, the incidence of complete
recovery (SCr returning to baseline) following acute rejection, the
incidence of subclinical rejection, and the incidence of all
treated acute rejection episodes regardless of histological
findings.
[0276] 6) Assess the effects of L104EA29YIg, relative to CsA, on a
composite cardiovascular disease endpoint (adjudicated
cardiovascular death, myocardial infarction, ischemic stroke,
non-elective hospitalization for cardiovascular cause, and
percutaneous coronary intervention) at 12, 24, and 36 months.
[0277] 7) Assess the effects of L104EA29YIg, relative to CsA, on a
composite cardiorenal disease endpoint (death, graft loss,
non-fatal myocardial infarction, and stroke) at 12, 24, and 36
months.
[0278] 8) Assess the effects of L104EA29YIg, relative to CsA, on
the Framingham Risk Score at 12, 24, and 36 months.
[0279] 9) Assess the effects of L104EA29YIg, relative to CsA, on
incidence of discontinuation of study drug.
[0280] 10) Assess the effects of L104EA29YIg, relative to CsA, on
anti-donor HLA antibodies.
[0281] 11) Assess the effects of L104EA29YIg, relative to CsA, on
C4d positivity in biopsy specimens.
[0282] Definition of Graft Loss Graft loss is defined as either
functional loss or physical loss. Functional loss will be defined
as a sustained level of SCr.gtoreq.6.0 mg/dL (530 .left brkt-top.
mmol/L) as determined by the central laboratory for .gtoreq.4 weeks
or .gtoreq.56 consecutive days of dialysis, or impairment of renal
function to such a degree that the subject received a second
transplant. All causes of graft loss will be adjudicated by an
independent EAC.
[0283] Definition of Delayed Graft Function (DGF) DGF is defined as
treatment with dialysis by study Day 8 (post-operative Day 7).
[0284] Definition of Chronic Allograft Nephropathy (CAN)
Biopsy-proven CAN will be determined by a blinded central
histopathologist using the Banff 97 working classification of
kidney transplant pathology. The incidence of CAN will be
determined by comparing all post-Day 1 biopsies to baseline
biopsies obtained at the time of transplant. This comparison
establishes the presence and severity of any preexisting
histopathology that may be later interpreted as CAN.
[0285] Definition of Post-transplant Diabetes Mellitus PTDM will be
defined according to the definition set forth by a recent
international consensus guideline. 20 These criteria are summarized
as: a.) Symptoms of diabetes plus casual plasma glucose (PG)
concentration .gtoreq.200 mg/dL (11.1 mmol/L) OR b.) fasting plasma
glucose (FPG) .gtoreq.126 mg/dL (7.0 mmol/L) OR c.) 2-hour
PG.gtoreq.200 mg/dL (11.1 mmol/L) during an oral glucose tolerance
test AND d.) a confirmatory laboratory test based on measurements
of venous PG must be done on another day in the absence of
unequivocal hyperglycemia accompanied by acute metabolic
decompensation. The study will utilize FPG for evaluation of PTDM,
however, if subjects are evaluated using these other methods and
found to meet the above criteria, they will be considered as having
PTDM.
[0286] Definition of Measures of Hypertension will be as defined in
this study according to the Seventh Report of the Joint National
Committee on the Prevention, Detection, Evaluation, and Treatment
of High Blood Pressure 21 for subjects with chronic kidney disease.
This definition is based upon SBP.gtoreq.130 mm Hg or DBP.gtoreq.80
mm Hg. In addition, all subjects who have a SBP<130 mm Hg and a
DBP<80 mm Hg who are receiving an antihypertensive medication(s)
for the indication of hypertension or with a medical history of
hypertension are included in this definition. The incidence of
hypertension is defined as the proportion of subjects who develop
hypertension after randomization and transplantation. The
prevalence of hypertension is defined as the proportion of subjects
at any given time who meet the above stated definition of
hypertension. Controlled hypertension is defined as a SBP<130 mm
Hg and a DBP<80 mm Hg while receiving an antihypertensive
medication for the indication of hypertension or receiving an
antihypertensive medication for another indication with a medical
history of hypertension. Subjects with a SBP<130 mm Hg and a
DBP<80 mm Hg who are prescribed an antihypertensive
medication(s) for an indication(s) of other than hypertension
(e.g., beta blockers for migraine prophylaxis) with no medical
history of hypertension will not be considered to have either
hypertension or controlled hypertension. Intensity of treatment
regimen is defined as the total number of antihypertensive
medications used to control hypertension. All antihypertensive
medications will be counted for the indication of hypertension in
subjects with hypertension or controlled hypertension since the
antihypertensive effects are present irrespective of
indication.
[0287] Definition of Measures of Dyslipidemia is defined in
accordance with recent guidelines from the National Kidney
Foundation Kidney Disease Outcomes Quality Initiative (NKF-K/DOQI).
22 Dyslipidemia is defined as hypertriglyceridemia (TGs .epsilon.
500 mg/dL [5.65 mmol/L]), hypercholesterolemia (LDL .+-.100 mg/dL
[2.59 mmol/L]), or elevated non-HDL (non-HDL .epsilon. 130 mg/dL
[3.36 mmol/L]) in the presence of high TGs (TGs .epsilon. 200 mg/dL
[2.26 mmol/L Controlled dyslipidemia is defined in this study as
subjects who are receiving pharmacological management for one of
the above stated dyslipidemias that is successfully treated, and
their lipid values fall below the thresholds described in the
previous paragraph. Some of these agents have specific precautions
and/or warnings regarding the starting dose or maximal recommended
dose with concomitant use of CsA, dosing with renal insufficiency,
or may cause alterations of CsA PK. Refer to the appropriate
package insert for specific recommendations. Any other agent (ie,
non-statin therapy) used as an antihyperlipidemic will be
considered Level I treatment intensity. Concomitant use of a statin
and an agent of another class (e.g., ezetimibe) will elevate the
intensity level of the statin therapy by 1 level; therefore, more
than 5 intensity levels are possible.
[0288] Acute rejection will be defined as a clinico-pathological
event requiring clinical evidence and biopsy confirmation.
Allograft biopsies will be evaluated for the presence and severity
of acute rejection by a blinded central independent pathologist
using Banff 97 working classification of kidney transplant
pathology. In the analyses of acute rejection the biopsy
interpretation and grading by the central pathologist will
supersede local interpretation. Biopsies performed for suspected
acute rejection that do not fully meet the criteria, but are
interpreted by the central pathologist as acute rejection and
result in treatment for acute rejection, will be counted as acute
rejection. Subclinical rejection is defined as histological
findings by the central pathologist consistent with acute
rejection, but lacking its clinical correlate. Steroid-resistant
acute rejection is defined as lack of improvement in the SCr and/or
histological findings that necessitate the use of
lymphocyte-depletion therapy following treatment with
corticosteroids. Framingham Risk Score This risk score utilizes
data from the Framingham Heart Study 23 to estimate 10-year risk
for `hard` coronary heart disease (myocardial infarction and
coronary death). The risk factors included in this calculation are
age, gender, total cholesterol, HDL cholesterol, SBP, diabetes,
treatment for hypertension, and any cigarette use in the prior
month.
Sample Size Determination
[0289] The primary objective is to estimate the effect of
L104EA29YIg on subject and graft survival rates and renal function
at 12 months as compared to CsA. The 2 co-primary endpoints are:
(1) the proportion of subjects with a surviving graft at 12 months
post-transplantation and (2) the proportion of subjects whose
measured GFR at 12 months is <60 mL/min/1.73 m.sup.2, and/or
whose measured GFR decreased .gtoreq.10 mL/min/1.73 m.sup.2 from
Month 3 to Month 12. A sample size of 180 subjects per treatment
group will afford 83% power to ascertain that the upper bound of
the 97.3% 2-sided CIs for the absolute difference (between each
L104EA29YIg regimen and the CsA regimen) in the first co-primary
endpoint (subject and graft survival) will not exceed 10%, if the
true subject and graft survival rate at 12 months is 80% for the
CsA regimen and 83% for each of the 2 L104EA29YIg regimens. For the
renal function endpoint, the sample size of 180 subjects per group
is powered to detect a decrease of 25% in the proportion of
subjects meeting the measured GFR endpoint for each L104EA29YIg
regimen as compared with the CsA regimen, assuming 75% of CsA
subjects meet the renal function endpoint and 25% drop-outs per
treatment group. Overall, 180 subjects per treatment group will
afford at least 80% power to detect 1 L104EA29YIg regimen that
meets both co-primary endpoints with overall Type I error
controlled at the 0.05 significance level (Dunnett adjustment).
Inclusion Criteria
[0290] Target Population: 1) The subject is a first-time recipient
of a deceased donor kidney transplant 2) The donor and/or donor
kidney meet at least 1 of the following extended criteria for organ
donation: a) Donor age .gtoreq.60 years OR b) Donor age 50-59 years
and 1 of the following: (i) Cerebrovascular accident
(CVA)+hypertension+SCr>1.5 mg/dL OR (ii) CVA+hypertension OR
(iii) CVA+SCr>1.5 mg/dL OR (iv) Hypertension+SCr>1.5 mg/dL OR
c) CIT.gtoreq.24 hours, donor age >10 years OR d) Donor with
cardiac death (non-heart beating donor) 3) Men and women, ages 18
and older, inclusive 4) WOCBP must be using an adequate method of
contraception to avoid pregnancy throughout the study and for up to
8 weeks after the study in such a manner that the risk of pregnancy
is minimized WOCBP includes any female who has experienced menarche
and who has not undergone successful surgical sterilization
(hysterectomy, bilateral tubal ligation, or bilateral oophorectomy)
or is not postmenopausal (defined as amenorrhea .gtoreq.12
consecutive months; or women on hormone replacement therapy with
documented serum follicle stimulating hormone level >35 mIU/mL).
Even women who are using oral, implanted, or injectable
contraceptive hormones or mechanical products such as an
intrauterine device or barrier methods (diaphragm, condoms,
spermicides) to prevent pregnancy or practicing abstinence or where
the partner is sterile (e.g., vasectomy), should be considered to
be of child bearing potential. WOCBP must have a negative serum
pregnancy test (minimum sensitivity 25 IU/L or equivalent units of
human chorionic gonadotropin [HCG]) within 72 hours prior to the
start of study medication. 5) Men must use an adequate method of
contraception throughout the study, and for up to 8 weeks after the
last infusion, so that the risk of pregnancy to their partners is
minimized.
Exclusion Criteria
[0291] 1) WOCBP who are unwilling or unable to use an acceptable
method to avoid pregnancy for the entire study period and for up to
8 weeks after the last infusion. 2) Women who are pregnant or
breastfeeding 3) Women with a positive pregnancy test on enrollment
or prior to study drug administration 4) Males unwilling or unable
to use an adequate method of contraception for the entire study
period and for up to 8 weeks after the last infusion of study
medication 5) Donor age <10 years 6) Subjects with underlying
renal disease of: a) Focal segmental glomerulosclerosis (biopsy
proven) b) Type I or II membranoproliferative glomerulonephritis c)
Hemolytic uremic syndrome/thrombotic thrombocytopenic purpura
syndrome 7) Subjects with current PRA.gtoreq.30% 8) Subjects with a
positive T-cell lymphocytotoxic crossmatch 9) Subjects with any
prior solid organ transplant (including kidney) 10) Subjects
receiving a concurrent solid organ (heart, liver, pancreas) or cell
(islet, bone marrow, stem cell) transplant 11) Subjects receiving
paired kidneys from the extended criteria donor (dual kidney
transplant) 12) Subjects who are hepatitis C antibody-positive or
polymerase chain reaction (PCR)-positive for hepatitis C 13)
Subjects who are hepatitis B surface antigen-positive or
PCR-positive for hepatitis B 14) Subjects with known human
immunodeficiency virus (HIV) infection 15) Subjects with active
tuberculosis (TB) requiring treatment within the previous 3 years
or any subject who previously required triple (or more) combination
therapy for TB. Subjects with a known positive purified protein
derivative (PPD) will not be eligible for the study unless they
completed treatment for latent TB and have a negative chest x-ray
at the time of enrollment. PPD testing done within the last 12
months is acceptable as long as there is documentation of the
results. Subjects without a PPD in the last 12 months who have a
previous negative result may be enrolled if they also have a
negative chest x-ray at enrollment, no symptoms indicative of TB,
no known TB contacts, not currently residing in, recently traveled
to, or previously immigrated from an area endemic for TB. A PPD
response that is .gtoreq.10 mm induration or a Heaf score of >1
in non-Bacille Calmette-Guerin (non-BCG) immunized subjects or
>2 in BCG immunized subjects should be considered a positive
test. More conservative criteria may be applied according to the
published guidelines and/or local standards endorsed by the medical
society 16) Subjects with any active infection or other
contraindication that would normally exclude transplantation 17)
Subjects whose life expectancy is severely limited by disease state
or other underlying medical condition 18) Subjects with a history
of cancer (other than non-melanoma skin cell cancers cured by local
resection) within the last 5 years 19) Subjects with a history of
substance abuse (drug or alcohol) within the past 5 years, or
psychotic disorders that are not compatible with adequate study
follow-up 20) Subjects with active peptic ulcer disease, chronic
diarrhea, or gastrointestinal malabsorption 21) Subjects with local
laboratory values that are Common Toxicity Criteria (CTC) Grade II
or greater may not participate in the study. However, certain
specified laboratory parameters that are exceptions to CTC Grade II
will be allowed. The following allowances are noted: Hematology:
Hemoglobin may be below CTC Grade II (but not below 8 g/dL)
Platelets may be below CTC Grade II, but not below 80,000/mm3
(80.times.109/L) Total white cell blood (WBC) count may be below
CTC Grade II, but not below 3000/mm3 (3.times.109/L) Granulocyte
and lymphocyte counts may be any value Chemistry: SCr and blood
urea nitrogen (BUN) values may be any value Blood glucose may be of
any value Urinalysis; Urinalysis results may be any value 22) All
women 40 years or older and women of any age who have first degree
relatives with a history of breast carcinoma or who have other risk
factors of breast carcinoma, must have a screening mammogram, or
provide results of a screening mammogram performed within 6 months
of enrollment. Subjects with a mammogram that is suspicious for
malignancy and in whom the possibility of malignancy cannot be
reasonably excluded following additional clinical, laboratory, or
other diagnostic evaluations will be excluded. If the screening
mammogram was not performed within 6 months of enrollment, but the
subject is deemed a suitable transplant candidate by local
criteria, the baseline mammogram may be obtained within 4 weeks
after transplant 23) Subjects who have difficult i.v. access or
other reasons that would likely preclude assessment of the
co-primary endpoint of measured GFR or subjects that are unlikely
(e.g., due to preexisting coagulation issues) or unwilling to
undergo the protocol specified 12-month allograft biopsy 24)
Subjects with a history of true allergy to i.v. iodinated x-ray
contrast agents 25) Subjects who have used any investigational drug
within 30 days prior to the Day 1 visit 26) Subjects previously
treated with L104EA29YIg 27) Prisoners or subjects who are
compulsorily detained (involuntarily incarcerated) for treatment of
either a psychiatric or physical (e.g., infectious disease) illness
must not be enrolled into this study.
Administration of L104EA29YIg
[0292] Day 1 is defined as the day of transplant (post-transplant
Day 0). Infusion of the Day 1 dose should begin after the surgeon
has made an initial intraoperative assessment, and has concluded
that the subject remains a transplant candidate and the transplant
will proceed, and before beginning the transplant vascular
anastomoses. Infusion doses will be based on the subject's actual
body weight at study Day 1, and will not be modified during the
course of the study, unless there is a change of body weight
.+-.10%. Study drug should be administered to the subject at a
relatively constant rate over 30 minutes. The Day 1 and Day 5
(post-transplant Day 4) doses should be administered approximately
96 hours apart (.+-.6 hours). Subsequent visit and infusion windows
are provided below. For subjects on dialysis, infusion of
L104EA29YIg and determination of the subject's weight should occur
after dialysis treatment.
[0293] L104EA29YIg MI Regimen: Subjects randomized to the MI
regimen will receive i.v. L104EA29YIg (10 mg/kg) on Days 1 and 5,
and then every other week for 2 months (Weeks 2, 4, 6, 8, 10, and
12), and then every 4 weeks until 6 months (Weeks 16, 20, and 24).
After 6 months, subjects in the MI treatment group will receive
L104EA29YIg at the maintenance dose of 5 mg/kg every 4 weeks until
completion of the trial at 36 months.
[0294] L104EA29YIg LI Regimen: Subjects randomized to the LI
regimen will receive i.v. L104EA29YIg (10 mg/kg) on Days 1 and 5,
and then every other week for 2 weeks (Weeks 2 and 4), and then
every 4 weeks for 2 months (Weeks 8 and 12). After 3 months,
subjects in the LI treatment group will receive L104EA29YIg at the
maintenance dose of 5 mg/kg every 4 weeks until completion of the
trial at 36 months. Blinding between the LI and MI group will be
preserved with the use of 2 placebo infusions in the LI treatment
group. Therefore, subjects randomized to the LI regimen will be
administered placebo (dextrose 5% in water for injection [D5W])
infusions on Weeks 6 and 10.
Administration of Cyclosporine (CsA)
[0295] The daily dose of CsA should be administered in 2 divided
doses on a consistent schedule in relation to time of day and
meals. On study visit days, the subject must withhold the morning
CsA dose until after trough CsA blood level draws. On study visit
days, when the subject is to have standardized BP monitoring and/or
measured GFR assessments, these measures are to be completed prior
to CsA dosing. The initial daily dose should be 7.+-.3 mg/kg (ie,
4-10 mg/kg). Subsequent doses should be adjusted to maintain a
predefined range of trough serum concentrations: 1st month: target
level 150-300 ng/mL After 1st month: target level of 100-250 ng/mL.
Monitoring of CsA levels using the plasma concentration 2 hours
post-dose (C2) is not to be used in this study. While a recent
international consensus statement on management of Neoral by C2
monitoring favored the use of C2 monitoring, it also clearly stated
the lack of data regarding the long-term effects on renal function,
incidence of CAN, and general safety profile associated with C2
monitoring. 24 Furthermore, not all subjects are suitable for C2
monitoring, including subjects with diabetes, slow gastric
emptying, or subjects using concomitant medication that alters CsA
clearance. Moreover, low C2 levels may result from either true low
absorption (in which the CsA dose should be increased) or from slow
absorption (in which there is a delayed maximum plasma
concentration and an increase in dose may produce toxicity).
Finally, this practice is not universal, and prospectively
validating this practice is beyond the scope of the current
protocol. For additional prescribing information, see the package
insert. CsA should be initiated in all subjects by Day 7. For
subjects in whom the investigator believes that it is not in the
best interest of the subject to initiate CsA at all (e.g., due to
impaired renal function), and elects to use a non-study medication
(e.g., sirolimus) instead, this action will be considered a
discontinuation of study medication.
[0296] For Subjects with Immediate Allograft Function: For subjects
randomized to treatment with CsA, the first dose of CsA should be
administered as soon as, but not until, there is evidence of
adequate allograft function. Adequate allograft function is defined
as a decrease in the SCr of at least 1 mg/dL compared to the
initial post-transplant value or urine output .gtoreq.250 mL in a
12 hour (or less) period post-transplant.
[0297] For Subjects with Impaired Renal Allograft Function and
Anticipated DGF: Subjects with postoperative impaired allograft
function and anticipated DGF are eligible--but not required--to
receive a polyclonal antilymphocyte preparation. Whether a subject
receives a polyclonal lymphocyte preparation or not, CsA should be
initiated when there is evidence of recovery of allograft function
(as defined above) or by Day 7.
Corticosteroids
[0298] All subjects in this study will be treated with daily
corticosteroids. STEROID MAINTENANCE--TAPER Day of transplant (Day
1): methylprednisolone (as sodium succinate) 500 mg i.v. on arrival
in the operating room (OR)
[0299] Day 2: methylprednisolone (as sodium succinate) 250 mg
i.v.
[0300] Day 3: prednisone (or prednisolone) 100 mg orally
(p.o.).
[0301] Day 4 through Day 14 (ie, end of Week 2): taper prednisone
(or prednisolone) to 20-30 mg p.o. daily.
[0302] Day 15 through Month 6: taper prednisone (or prednisolone)
no lower than 2.5 mg p.o. daily
[0303] Subjects must remain on at least 2.5 mg p.o. daily through
Year 3.
[0304] The first 2 doses (study Day 1, day of transplant and study
Day 2, post-operative Day 1) are to be administered i.v. The
remaining doses are to be administered p.o. However, i.v. dosing of
an equivalent dose of methylprednisolone is permitted at times when
oral dosing is not possible. Such reasons for i.v. rather than p.o.
dosing are intercurrent illness, postoperative ileus, or other
causes at the investigator's discretion. If methylprednisolone is
not available, the use of another i.v. corticosteroid agent
dose-equivalent to methylprednisolone is permitted.
Mycophenolate Mofetil Dosing
[0305] All subjects in this study will be treated with MMF. Daily
MMF should be administered in 2 divided doses on a consistent
schedule in relation to time of day and meals. The dose should be 2
g daily; however, in African Americans, 3 g daily may be
administered at the investigator's discretion. 25 MMF should be
administered p.o. Intravenous dosing is permitted, if needed due to
intercurrent illness, postoperative ileus, or other causes at the
investigator's discretion. The first dose should be administered
preoperatively. Subsequent doses should be administered p.o. as
soon as the subject is able to tolerate medications by mouth. The
dose and schedule may be adjusted determined on the basis of
laboratory values (e.g., decreased WBCs) and subject tolerability
(see below). For full prescribing information, see the package
insert.
[0306] For subjects who develop nausea, diarrhea, or other
MMF-related gastrointestinal adverse effects (e.g., symptoms fully
assessed and deemed not to have an etiology other than
intolerability to MMF), the MMF dose may be decreased to the
maximally tolerated dose. For subjects who develop neutropenia
(absolute neutrophil count <1.3.times.103/.left brkt-top. L),
dosing with MMF should be interrupted or dose reduced as per the
package insert.
Basiliximab Dosing
[0307] All subjects in this study will be treated with the
recommended dosing regimen of basiliximab. Basiliximab should be
administered through a peripheral or central vein only.
Reconstituted basiliximab (20 mg in 5 mL) should be diluted to a
volume of 50 mL with normal saline or dextrose 5% and administered
as an i.v. infusion over 20-30 minutes. The first 20 mg dose should
be administered on Day 1 (the day of transplantation;
post-operative Day 0). For subjects randomized to L104EA29YIg, this
first basiliximab infusion should occur as soon as possible after
completion of the L104EA29YIg infusion. The second 20 mg dose
should be given on Day 5 (post-operative Day 4). The second
basiliximab dose should not be administered to subjects if they
have received or are expected to receive a lymphocyte-depleting
treatment. For additional information, see the package insert.
Polyclonal Antilymphocyte Preparations for Impaired Renal Allograft
Function and Anticipated DGF
[0308] The use of polyclonal antilymphocyte preparations
(Thymoglobulin or ATGAM) is permitted--but not required--for
subjects randomized to CsA who experience impaired renal allograft
function and anticipated DGF following transplantation. Use of
other polyclonal antilymphocyte preparations or polyclonal
antithymocyte globulins is permitted in regions where market
authorization exists, and if they are indicated for the treatment
of acute rejection in renal transplantation. Of note, OKT3 is not
to be used for this purpose, but may be used for treatment of Banff
97 Grade IIb or greater acute rejection or steroid-resistant acute
rejection. Use of Campath 1-H.RTM. (alemtuzumab) is not permitted
in this protocol, as it is not indicated for use in kidney
transplantation. These agents are widely utilized in this capacity
to afford immunosuppression until graft function allows for
administration of CsA. Therefore, polyclonal antilymphocyte
preparations may be used in this clinical setting, at the
investigator's discretion, in subjects who meet .gtoreq.1 of the
following criteria that are observed in the presence of a patent
transplant artery and vein and no evidence of hydronephrosis by
sonogram: a.) Urine output <250 cc/12 hours b.) No significant
improvement (<1 mg/dL) in SCr from baseline value over the first
24-72 hours post-transplant c.) Dialysis treatment. Use of these
agents for impaired renal allograft function and anticipated DGF is
not permitted in L104EA29YIg-treated subjects.
Sulfamethoxazole/Trimethoprim Dosing
[0309] All subjects who participate in this study who have no
contraindications should receive sulfamethoxazole/trimethoprim
prophylaxis to prevent urinary tract and Pneumocystis carinii
infections. Dosing and administration are to be determined by the
level of renal function consistent with the package insert.
Subjects with a contraindication or intolerance to sulfa drugs or
trimethoprim may receive prophylactic therapy with inhaled
pentamidine at the investigator's discretion. For full prescribing
information, see the package inserts.
Valganciclovir/Ganciclovir, Acyclovir/Valacyclovir Dosing
[0310] All recipients who have no contraindications to
valganciclovir, ganciclovir, acyclovir, and valacyclovir should be
prophylactically treated with these drugs to prevent infections due
to CMV and Herpes simplex. The following are guidelines for dosing
and duration of prophylactic treatment:
[0311] Prophylaxis for the First 10 Days Post-transplant or During
T-cell-depleting Therapy: All transplant subjects will receive
valganciclovir or ganciclovir per protocol for 10 days after
surgery. If treated with T-cell-depleting therapy for induction
therapy or treatment for acute rejection, the subject will receive
valganciclovir or ganciclovir for the duration of the
T-cell-depleting therapy. If the subject is discharged prior to 10
days, either oral valganciclovir, ganciclovir, valacyclovir, or
acyclovir will begin based on CMV immune status as described
below.
[0312] Valganciclovir for Prophylaxis: Creatinine Clearance 20
mL/min, dose 900 mg daily; Creatinine Clearance 40-59 mL/min, dose
450 mg daily; Creatinine Clearance <40 mL/min, dose 450 mg every
other day.
[0313] Ganciclovir for Prophylaxis: If the subject is unable to
tolerate oral medications, or valganciclovir is not available for
use, ganciclovir suspension or capsules may be substituted.
Creatinine Clearance .gtoreq.70 mL/min, dose 1 g 3 times daily;
Creatinine Clearance 50-69 mL/min, dose 500 mg 3 times daily;
Creatinine Clearance 25-49 mL/min, dose 500 mg twice daily;
Creatinine Clearance 10-24 mL/min, dose 500 mg daily; Creatinine
Clearance <10 mL/min, dose 500 mg after hemodialysis 3
times/week. If i.v. ganciclovir is needed, see the package insert
for dosing.
[0314] Prophylaxis After 10 Days Post-transplant Through at Least 3
Months: CMV Antibody Seropositive Donor to a CMV Antibody
Seronegative Recipient: Continue valganciclovir or ganciclovir
protocol listed above for .gtoreq.3 months.
[0315] CMV Antibody Seropositive or Seronegative Donor to a CMV
Antibody Seropositive Recipient Oral acyclovir for .gtoreq.3 months
post-transplantation: Serum Creatinine .gtoreq.50 mL/min, dose 800
mg orally 4 times daily; Serum Creatinine 25-49 mL/min, dose 800 mg
orally 3 times daily; Serum Creatinine 11-24 mL/min, dose 800 mg
orally twice daily; Serum Creatinine <10 mL/min, dose 800 mg
orally daily; On hemodialysis, dose 800 mg daily after
hemodialysis
[0316] Valacyclovir may be substituted for acyclovir at the time of
discharge for subject convenience. Serum Creatinine .gtoreq.50
mL/min, dose 500 mg orally 2 times daily; Serum Creatinine 25-49
mL/min, dose 500 mg orally daily; Serum Creatinine 11-24 mL/min,
dose 500 mg orally daily; Serum Creatinine <10 mL/min, dose 250
mg orally daily; On hemodialysis, dose 250 mg daily after
hemodialysis
[0317] CMV Antibody Seronegative Donor to a CMV Antibody
Seronegative Recipient: Oral Acyclovir Protocol Needed for Herpes
Prophylaxis Only: continue for .gtoreq.3 months
post-transplantation. Acyclovir 400 mg p.o. twice daily or
valacyclovir may be substituted for acyclovir at the time of
discharge for subject convenience. For full prescribing
information, refer to the package inserts.
Infusion-Only Visit Procedures
[0318] a) For subjects randomized to L104EA29YIg treatment: A
negative pregnancy test is required prior to L104EA29YIg
administration. The dose is to be based on the subject's weight at
the most recent previous study visit. Subjects should be monitored
for vital signs (pre- and post-infusion), and AEs should be
assessed. PK samples may be required at some visits.
[0319] b) For subjects randomized to CsA treatment: Subjects shall
be contacted to assess for AEs only. This visit can be a telephone
contact, and should occur within the prescribed visit window for
the specified visit.
Visit Windows
[0320] a) For subjects randomized to L104EA29YIg treatment: the
Days 1 and 5 doses should be administered approximately 96 hours
apart (.+-.6 hours). To facilitate scheduling the infusion-only
visits, the following windows are permitted for subsequent doses:
Visit Week 2, Visit Window target date .+-.2 days; Visit Week
4-Month 6 Visit Window target date .+-.3 days, Visit Month 7-Month
36, Visit Window target date .+-.5 days; Visit follow-up 8 weeks,
Visit Window target date .+-.5 days.
[0321] b) For subjects randomized to CsA treatment: After Day 5,
subjects are only required to attend clinic visits at Weeks 2, 4,
8, and 12; then at every 3-month interval visit. At the non-3-month
interval visits (ie, Weeks 6, 10, 16, 20, 28, 32, etc), a telephone
contact will be conducted to collect AE information. Clinic and
contact visits shall occur within the same visit windows as
specified above for subjects randomized to L104EA29YIg. The target
dates for the 3- and 12-month GFR assessments are Week 12.+-.14
days and Week 52.+-.14 days. Under certain circumstances, and with
the prior approval of the medical monitor, the measured GFR
assessments at Month 3 and Month 12 may be conducted through Month
6 and Month 15, respectively. Such reasons that may warrant
extension of a measured GFR assessment include the presence of a
concurrent acute rejection episode or the need to repeat an
assessment for technical reasons.
[0322] The target date for the 12-month allograft biopsy is Week
52.+-.14 days. Similarly, under certain circumstances and with the
prior approval of the medical monitor, the allograft biopsy may be
obtained through Month 15. Such reasons that may warrant extension
of an allograft biopsy include temporary need for anti
coagulation.
Example 5
[0323] One knowledgeable in the art could utilize the
administration schedule described in Example 4 above to design a
study comprising a different study population, donor criteria
and/or objectives. For example, this transplant study will evaluate
subjects receiving a kidney transplant from a living donor or
deceased donor with anticipated cold-ischemic time <24 hours.
Subjects at varying levels of immunological risk will be eligible.
However, the study will exclude subjects of greatest immunological
risk. Subjects will be randomized to the MI, LI or CsA arms as
described above in Example 4.
Primary Objectives
[0324] Evaluate the effects of L104EA29YIg, relative to CsA, on the
composite of subject and graft survival by 12 months. Evaluate the
effects of L104EA29YIg, relative to CsA, on the composite of
measured GFR<60 mL/min/1.73 m.sup.2 at Month 12 or a decrease in
measured GFR.gtoreq.10 mL/min/1.73 m.sup.2 from Month 3 to Month
12. Evaluate the effects of L104EA29YIg, relative to CsA, on the
incidence of acute rejection by 12 months.
Secondary Objectives
[0325] Evaluate the effects of L104EA29YIg, relative to CsA, on
measured GFR at 12 months. Evaluate the effects of L104EA29YIg,
relative to CsA, on biopsy-proven CAN at 12 months. Assess the
effects of L104EA29YIg, relative to CsA, on the individual
components of the primary composite endpoint of measured GFR<60
mL/min/1.73 m.sup.2 at Month 12 or a decrease in measured
GFR.gtoreq.10 mL/min/1.73 m.sup.2 from Month 3 to Month 12. Assess
the effects of L104EA29YIg, relative to CsA, on the triple
composite endpoint of death, graft loss, and acute rejection by 12,
24, and 36 months. Assess the effects of L104EA29YIg, relative to
CsA, on the proportion of subjects with a measured GFR<60
mL/min/1.73 m.sup.2 at 24 months Assess the effects of L104EA29YIg,
relative to CsA, on measured GFR at 3 and 24 months, and change
from baseline (3 months) to 12 months and to 24 months. Assess the
effects of L104EA29YIg, relative to CsA, on the proportion of
subjects with a measured GFR<30 mL/min/1.73 m.sup.2 at 12 and 24
months. Assess the effects of L104EA29YIg, relative to CsA, on
calculated GFR at 6, 12, 24, and 36 months, and change from 6
months to 12, 24, and 36 months. Assess the effects of L104EA29YIg,
relative to CsA, on PTDM by 12, 24, and 36 months. Assess the
effects of L104EA29YIg, relative to CsA, on measures of
hypertension at 12, 24, and 36 months, including SBP and DBP,
incidence and prevalence of hypertension and controlled
hypertension, and intensity of treatment regimen. Assess the
effects of L104EA29YIg, relative to CsA, on measures of
dyslipidemia, at 12, 24, and 36 months, including serum total,
non-HDL, low-density lipoprotein (LDL), and HDL cholesterol, and
TGs, incidence and prevalence of dyslipidemia and controlled
dyslipidemia, and intensity of treatment regimen. Evaluate the
effects of L104EA29YIg, relative to CsA, on subject and graft
survival by 24 and 36 months. Assess the effects of L104EA29YIg,
relative to CsA, on the proportion of subjects with a calculated
GFR<60 mL/min/1.73 m.sup.2 at 24 and 36 months. Assess the
effects of L104EA29YIg, relative to CsA, on measures of acute
rejection by 6, 12, 24, and 36 months, including the incidence and
severity of acute rejection, the use of polyclonal antilymphocyte
preparations for impaired renal function and anticipated delayed
graft function (DGF), the initial use of lymphocyte-depleting
therapy for treatment of acute rejection, the incidence of
steroid-resistant acute rejection, the incidence of complete
recovery (SCr returning to baseline) following acute rejection, the
incidence of subclinical rejection, the incidence of all treated
acute rejection episodes regardless of histological findings, and
the time to onset of acute rejection. Evaluate the effects of
L104EA29YIg, relative to CsA, on QoL. Assess the overall safety of
L104EA29YIg, relative to CsA. Assess the effects of L104EA29YIg,
relative to CsA, on the slope and intercept of calculated GFR from
3 months to 12, 24, and 36 months. Assess the effects of
L104EA29YIg, relative to CsA, on the proportion of subjects with
<60 mL/min/1.73 m.sup.2 calculated GFR at Month 12 or subjects
with a decrease in calculated GFR from Month 3 to Month 12 of at
least 10 mL/min/1.73 m.sup.2. Assess the effects of L104EA29YIg,
relative to CsA, on the incidence of DGF. Assess the effects of
L104EA29YIg, relative to CsA, on the proportion of subjects with
Stage 1 through Stage 5 chronic kidney disease at 12 and 24 months
as assessed by measured GFR. Assess the effects of L104EA29YIg,
relative to CsA, on the proportion of subjects with Stage 1 through
Stage 5 chronic kidney disease at 36 months as assessed by
calculated GFR. Assess the effects of L104EA29YIg, relative to CsA,
on a composite cardiovascular disease endpoint (adjudicated
cardiovascular death, myocardial infarction, ischemic stroke, and
revascularization [surgical or percutaneous] procedures) by 12, 24,
and 36 months. Assess the effects of L104EA29YIg, relative to CsA,
on a composite cardiorenal disease endpoint (death, graft loss,
non-fatal myocardial infarction, and stroke) by 12, 24, and 36
months. Assess the effects of L104EA29YIg, relative to CsA, on the
Framingham Risk Score at 12, 24, and 36 months. Assess the effects
of L104EA29YIg, relative to CsA, on incidence of discontinuation of
study drug. Assess the effects of L104EA29YIg, relative to CsA, on
anti-donor human leukocyte antigen (HLA) antibodies. Assess the
effects of L104EA29YIg, relative to CsA, on angiotensin II type 1
(AT1)-receptor antibodies Assess the effects of L104EA29YIg,
relative to CsA, on C4d positivity in biopsy specimens
Study Design
[0326] The duration of the study is 3 years with a subsequent
8-week follow-up period for safety evaluations. This is a
randomized, partially-blinded, active-controlled, parallel-group
study. All subjects will receive a kidney transplant from a living
donor or a deceased donor with an anticipated CIT<24 hours.
[0327] Approximately 660 subjects will be randomized in a 1:1:1
ratio to treatment with either L104EA29YIg (MI regimen),
L104EA29YIg (LI regimen), or CsA. All subjects will also receive
induction with basiliximab and a background maintenance
immunosuppressive regimen of MMF and corticosteroids. Subjects
randomized to the MI regimen will receive i.v. L104EA29YIg (10
mg/kg) on Days 1 and 5, then every 2 weeks through Month 3 (Weeks
2, 4, 6, 8, 10, and 12), and then every 4 weeks through 6 months
(Weeks 16, 20, and 24). After 6 months, subjects in the MI
treatment group will receive the maintenance dose of L104EA29YIg 5
mg/kg administered every 4 weeks until completion of the trial at
36 months. Subjects randomized to the LI regimen will receive i.v.
L104EA29YIg (10 mg/kg) on Days 1 and 5, and then every 2 weeks
through Month 1 (Weeks 2 and 4), and every 4 weeks through Month 3
(Weeks 8 and 12). After 3 months, subjects in the LI treatment
group will receive the maintenance dose of L104EA29YIg 5 mg/kg
administered every 4 weeks until completion of the trial at 36
months. Blinding between the LI and MI groups will be preserved
with the use of placebo infusions in the LI treatment group on
Weeks 6 and 10. Subjects randomized to CsA will receive doses twice
daily that are designed to achieve a specified trough serum
concentration range consistent with current medical practice. The
safety and efficacy of L104EA29YIg will be assessed at 1, 2, and 3
years. An independent DSMB will review data from the study on an
ongoing basis, and make recommendations for altering the conduct of
the trial, if necessary.
Study Population
[0328] The study population includes recipients of renal allografts
from living donors or deceased donors with an anticipated CIT<24
hours. In general, immunological criteria will not play a major
role in subject selection. Subjects at varying levels of
immunological risk are eligible. The study will, however, exclude
subjects of greatest immunological risk (positive cross match,
current panel reactive antibodies [PRA] of .gtoreq.50%, or those
previously transplanted with a current PRA.gtoreq.30%). These
subjects may require therapy to reduce their antibody load, such as
plasmapheresis, which is beyond the scope of this protocol.
Subjects will be enrolled at approximately 100 sites globally.
Inclusion Criteria
[0329] Target Population: 1) The subject is a recipient of a living
donor or deceased donor kidney transplant with an anticipated
CIT<24 hours 2) Men and women, ages 18 and older, inclusive 3)
WOCBP must be using an adequate method of contraception to avoid
pregnancy throughout the study and for up to 8 weeks after the
study in such a manner that the risk of pregnancy is minimized
WOCBP includes any female who has experienced menarche and who has
not undergone successful surgical sterilization (hysterectomy,
bilateral tubal ligation, or bilateral oophorectomy) or is not
postmenopausal (defined as amenorrhea for 12 consecutive months; or
women on hormone replacement therapy [HRT] with documented serum
follicle stimulating hormone [FSH] level >35 mIU/mL). Even women
who are using oral, implanted, or injectable contraceptive hormones
or mechanical products such as an intrauterine device or barrier
methods (diaphragm, condoms, spermicides) to prevent pregnancy or
practicing abstinence or where the partner is sterile (e.g.,
vasectomy), should be considered to be of childbearing potential.
WOCBP must have a negative serum pregnancy test (minimum
sensitivity 25 IU/L or equivalent units of human chorionic
gonadotropin [HCG]) within 72 hours prior to the start of study
medication.
Exclusion Criteria
[0330] 1) WOCBP who are unwilling or unable to use an acceptable
method to avoid pregnancy for the entire study period and for up to
8 weeks after the last infusion. 2) Women who are pregnant or
breastfeeding. 3) Women with a positive pregnancy test on
enrollment or prior to study drug administration. 4)
Genetically-identical donor recipient pairs (ie, identical twins).
5) Donor age <10 years. 6) Subjects receiving and extended
criteria donor organ as defined by: a) Donor age .gtoreq.60 years
OR b) Donor age 50-59 years and 1 of the following: (i)
Cerebrovascular accident (CVA)+hypertension+SCr>1.5 mg/dL OR
(ii) CVA+hypertension OR (iii) CVA+SCr>1.5 mg/dL OR (iv)
Hypertension+SCr>1.5 mg/dL OR c) Anticipated CIT.gtoreq.24 hours
OR d) Donor with cardiac death (non-heart beating donor). 7)
Subjects with underlying renal disease of: a) Primary focal
segmental glomerulosclerosis b) Type I or II membranoproliferative
glomerulonephritis c) Hemolytic uremic syndrome (HUS)/thrombotic
thrombocytopenic purpura syndrome If a subject has ESRD of unknown
etiology and/or has no histologically-confirmed diagnosis, the
subject may be enrolled into the study as long as there are no
clinical signs or symptoms consistent with the clinical diagnosis
of primary focal segmental glomerulosclerosis, Type I or II
membranoproliferative glomerulonephritis, or HUS, as deemed by the
investigator. 8) Subjects undergoing primary (first-time)
transplant with a current PRA.gtoreq.50%, or subjects undergoing
retransplantation with a PRA .epsilon. 30%. 9) Subjects with
previous graft loss due to acute rejection. 10) Subjects with a
positive T-cell lymphocytotoxic cross match. 11) Subjects with
prior non-renal solid organ transplant (subjects undergoing kidney
retransplantation are eligible pending other study criteria being
met), or subjects undergoing multi-organ transplants (e.g.,
kidney-pancreas) or subjects deemed likely to have a second solid
organ or cell transplant (e.g., pancreas or islet transplant) in
the next 3 years by the investigator. 12) Subjects receiving a
concurrent solid organ (heart, liver, pancreas) or cell (islet,
bone marrow, stem cell) transplant. 13) Subjects receiving paired
kidneys (dual or en bloc kidney transplants). 14) Subjects who are
known hepatitis C antibody-positive or polymerase chain reaction
(PCR)-positive for hepatitis C. 15) Subjects who are known
hepatitis B surface antigen-positive or PCR-positive for hepatitis
B. 16) Subjects with known human immunodeficiency virus (HIV)
infection. 17) Subjects with active tuberculosis (TB) requiring
treatment within the previous 3 years or any subject who previously
required triple (or more) combination therapy for TB. Subjects with
a known positive purified protein derivative (PPD) will not be
eligible for the study unless they completed treatment for latent
TB and have a negative chest x-ray at the time of enrollment. PPD
testing done within the last 12 months is acceptable as long as
there is documentation of the results. Subjects without a PPD in
the last 12 months who have a previous negative result may be
enrolled if they also have a negative chest x-ray at enrollment, no
symptoms indicative of TB, no known TB contacts, is not currently
residing in, recently traveled to, or previously immigrated from an
area endemic for TB. A PPD response that is .ltoreq.10 mm
induration or a Heaf score of >1 in non-Bacille Calmette-Guerin
(non-BCG) immunized subjects or >2 in BCG immunized subjects
should be considered a positive test. More conservative criteria
may be applied according to the published guidelines and/or local
standards endorsed by the medical society. 18) Subjects with any
active infection or other contraindication that would normally
exclude transplantation. 19) Subjects whose life expectancy is
severely limited by disease state or other underlying medical
condition. 20) Subjects with a history of cancer (other than
non-melanoma skin cell cancers cured by local resection) within the
last 5 years. 21) Subjects with a history of substance abuse (drug
or alcohol) within the past 5 years, or psychotic disorders that
are not compatible with adequate study followup. 22) Subjects with
active peptic ulcer disease, chronic diarrhea, or gastrointestinal
malabsorption.
[0331] Administration of and visit windows for L104EA29YIg MI and
LI and CsA regimens, including list as required, will be as
described above and in Example 4.
[0332] As will be apparent to those skilled in the art to which the
invention pertains, the present invention may be embodied in forms
other than those specifically disclosed above without departing
from the spirit or essential characteristics of the invention. The
particular embodiments of the invention described above, are,
therefore, to be considered as illustrative and not restrictive.
The scope of the present invention is as set forth in the appended
claims rather than being limited to the examples contained in the
foregoing description.
Sequence CWU 1
1
10141DNAArtificial SequenceOncostatin M CTLA4 (OMCTLA4) Forward
Primer 1gaggtgataa agcttcacca atgggtgtac tgctcacaca g
41242DNAArtificial SequenceOncostatin M CTLA4 (OMCTLA4) Reverse
Primer 2gtggtgtatt ggtctagatc aatcagaatc tgggcacggt tc
4231152DNAArtificial SequenceL104EA29YIg 3atgggtgtac tgctcacaca
gaggacgctg ctcagtctgg tccttgcact cctgtttcca 60agcatggcga gcatggcaat
gcacgtggcc cagcctgctg tggtactggc cagcagccga 120ggcatcgcta
gctttgtgtg tgagtatgca tctccaggca aatatactga ggtccgggtg
180acagtgcttc ggcaggctga cagccaggtg actgaagtct gtgcggcaac
ctacatgatg 240gggaatgagt tgaccttcct agatgattcc atctgcacgg
gcacctccag tggaaatcaa 300gtgaacctca ctatccaagg actgagggcc
atggacacgg gactctacat ctgcaaggtg 360gagctcatgt acccaccgcc
atactacgag ggcataggca acggaaccca gatttatgta 420attgatccag
aaccgtgccc agattctgat caggagccca aatcttctga caaaactcac
480acatccccac cgtccccagc acctgaactc ctggggggat cgtcagtctt
cctcttcccc 540ccaaaaccca aggacaccct catgatctcc cggacccctg
aggtcacatg cgtggtggtg 600gacgtgagcc acgaagaccc tgaggtcaag
ttcaactggt acgtggacgg cgtggaggtg 660cataatgcca agacaaagcc
gcgggaggag cagtacaaca gcacgtaccg tgtggtcagc 720gtcctcaccg
tcctgcacca ggactggctg aatggcaagg agtacaagtg caaggtctcc
780aacaaagccc tcccagcccc catcgagaaa accatctcca aagccaaagg
gcagccccga 840gaaccacagg tgtacaccct gcccccatcc cgggatgagc
tgaccaagaa ccaggtcagc 900ctgacctgcc tggtcaaagg cttctatccc
agcgacatcg ccgtggagtg ggagagcaat 960gggcagccgg agaacaacta
caagaccacg cctcccgtgc tggactccga cggctccttc 1020ttcctctaca
gcaagctcac cgtggacaag agcaggtggc agcaggggaa cgtcttctca
1080tgctccgtga tgcatgaggc tctgcacaac cactacacgc agaagagcct
ctccctgtct 1140ccgggtaaat ga 11524383PRTArtificial
SequenceL104EA29YIg 4Met Gly Val Leu Leu Thr Gln Arg Thr Leu Leu
Ser Leu Val Leu Ala1 5 10 15Leu Leu Phe Pro Ser Met Ala Ser Met Ala
Met His Val Ala Gln Pro 20 25 30Ala Val Val Leu Ala Ser Ser Arg Gly
Ile Ala Ser Phe Val Cys Glu 35 40 45Tyr Ala Ser Pro Gly Lys Tyr Thr
Glu Val Arg Val Thr Val Leu Arg 50 55 60Gln Ala Asp Ser Gln Val Thr
Glu Val Cys Ala Ala Thr Tyr Met Met65 70 75 80Gly Asn Glu Leu Thr
Phe Leu Asp Asp Ser Ile Cys Thr Gly Thr Ser 85 90 95Ser Gly Asn Gln
Val Asn Leu Thr Ile Gln Gly Leu Arg Ala Met Asp 100 105 110Thr Gly
Leu Tyr Ile Cys Lys Val Glu Leu Met Tyr Pro Pro Pro Tyr 115 120
125Tyr Glu Gly Ile Gly Asn Gly Thr Gln Ile Tyr Val Ile Asp Pro Glu
130 135 140Pro Cys Pro Asp Ser Asp Gln Glu Pro Lys Ser Ser Asp Lys
Thr His145 150 155 160Thr Ser Pro Pro Ser Pro Ala Pro Glu Leu Leu
Gly Gly Ser Ser Val 165 170 175Phe Leu Phe Pro Pro Lys Pro Lys Asp
Thr Leu Met Ile Ser Arg Thr 180 185 190Pro Glu Val Thr Cys Val Val
Val Asp Val Ser His Glu Asp Pro Glu 195 200 205Val Lys Phe Asn Trp
Tyr Val Asp Gly Val Glu Val His Asn Ala Lys 210 215 220Thr Lys Pro
Arg Glu Glu Gln Tyr Asn Ser Thr Tyr Arg Val Val Ser225 230 235
240Val Leu Thr Val Leu His Gln Asp Trp Leu Asn Gly Lys Glu Tyr Lys
245 250 255Cys Lys Val Ser Asn Lys Ala Leu Pro Ala Pro Ile Glu Lys
Thr Ile 260 265 270Ser Lys Ala Lys Gly Gln Pro Arg Glu Pro Gln Val
Tyr Thr Leu Pro 275 280 285Pro Ser Arg Asp Glu Leu Thr Lys Asn Gln
Val Ser Leu Thr Cys Leu 290 295 300Val Lys Gly Phe Tyr Pro Ser Asp
Ile Ala Val Glu Trp Glu Ser Asn305 310 315 320Gly Gln Pro Glu Asn
Asn Tyr Lys Thr Thr Pro Pro Val Leu Asp Ser 325 330 335Asp Gly Ser
Phe Phe Leu Tyr Ser Lys Leu Thr Val Asp Lys Ser Arg 340 345 350Trp
Gln Gln Gly Asn Val Phe Ser Cys Ser Val Met His Glu Ala Leu 355 360
365His Asn His Tyr Thr Gln Lys Ser Leu Ser Leu Ser Pro Gly Lys 370
375 38051152DNAArtificial SequenceL104EIg 5atgggtgtac tgctcacaca
gaggacgctg ctcagtctgg tccttgcact cctgtttcca 60agcatggcga gcatggcaat
gcacgtggcc cagcctgctg tggtactggc cagcagccga 120ggcatcgcta
gctttgtgtg tgagtatgca tctccaggca aagccactga ggtccgggtg
180acagtgcttc ggcaggctga cagccaggtg actgaagtct gtgcggcaac
ctacatgatg 240gggaatgagt tgaccttcct agatgattcc atctgcacgg
gcacctccag tggaaatcaa 300gtgaacctca ctatccaagg actgagggcc
atggacacgg gactctacat ctgcaaggtg 360gagctcatgt acccaccgcc
atactacgag ggcataggca acggaaccca gatttatgta 420attgatccag
aaccgtgccc agattctgat caggagccca aatcttctga caaaactcac
480acatccccac cgtccccagc acctgaactc ctggggggat cgtcagtctt
cctcttcccc 540ccaaaaccca aggacaccct catgatctcc cggacccctg
aggtcacatg cgtggtggtg 600gacgtgagcc acgaagaccc tgaggtcaag
ttcaactggt acgtggacgg cgtggaggtg 660cataatgcca agacaaagcc
gcgggaggag cagtacaaca gcacgtaccg tgtggtcagc 720gtcctcaccg
tcctgcacca ggactggctg aatggcaagg agtacaagtg caaggtctcc
780aacaaagccc tcccagcccc catcgagaaa accatctcca aagccaaagg
gcagccccga 840gaaccacagg tgtacaccct gcccccatcc cgggatgagc
tgaccaagaa ccaggtcagc 900ctgacctgcc tggtcaaagg cttctatccc
agcgacatcg ccgtggagtg ggagagcaat 960gggcagccgg agaacaacta
caagaccacg cctcccgtgc tggactccga cggctccttc 1020ttcctctaca
gcaagctcac cgtggacaag agcaggtggc agcaggggaa cgtcttctca
1080tgctccgtga tgcatgaggc tctgcacaac cactacacgc agaagagcct
ctccctgtct 1140ccgggtaaat ga 11526383PRTArtificial SequenceL104EIg
6Met Gly Val Leu Leu Thr Gln Arg Thr Leu Leu Ser Leu Val Leu Ala1 5
10 15Leu Leu Phe Pro Ser Met Ala Ser Met Ala Met His Val Ala Gln
Pro 20 25 30Ala Val Val Leu Ala Ser Ser Arg Gly Ile Ala Ser Phe Val
Cys Glu 35 40 45Tyr Ala Ser Pro Gly Lys Ala Thr Glu Val Arg Val Thr
Val Leu Arg 50 55 60Gln Ala Asp Ser Gln Val Thr Glu Val Cys Ala Ala
Thr Tyr Met Met65 70 75 80Gly Asn Glu Leu Thr Phe Leu Asp Asp Ser
Ile Cys Thr Gly Thr Ser 85 90 95Ser Gly Asn Gln Val Asn Leu Thr Ile
Gln Gly Leu Arg Ala Met Asp 100 105 110Thr Gly Leu Tyr Ile Cys Lys
Val Glu Leu Met Tyr Pro Pro Pro Tyr 115 120 125Tyr Glu Gly Ile Gly
Asn Gly Thr Gln Ile Tyr Val Ile Asp Pro Glu 130 135 140Pro Cys Pro
Asp Ser Asp Gln Glu Pro Lys Ser Ser Asp Lys Thr His145 150 155
160Thr Ser Pro Pro Ser Pro Ala Pro Glu Leu Leu Gly Gly Ser Ser Val
165 170 175Phe Leu Phe Pro Pro Lys Pro Lys Asp Thr Leu Met Ile Ser
Arg Thr 180 185 190Pro Glu Val Thr Cys Val Val Val Asp Val Ser His
Glu Asp Pro Glu 195 200 205Val Lys Phe Asn Trp Tyr Val Asp Gly Val
Glu Val His Asn Ala Lys 210 215 220Thr Lys Pro Arg Glu Glu Gln Tyr
Asn Ser Thr Tyr Arg Val Val Ser225 230 235 240Val Leu Thr Val Leu
His Gln Asp Trp Leu Asn Gly Lys Glu Tyr Lys 245 250 255Cys Lys Val
Ser Asn Lys Ala Leu Pro Ala Pro Ile Glu Lys Thr Ile 260 265 270Ser
Lys Ala Lys Gly Gln Pro Arg Glu Pro Gln Val Tyr Thr Leu Pro 275 280
285Pro Ser Arg Asp Glu Leu Thr Lys Asn Gln Val Ser Leu Thr Cys Leu
290 295 300Val Lys Gly Phe Tyr Pro Ser Asp Ile Ala Val Glu Trp Glu
Ser Asn305 310 315 320Gly Gln Pro Glu Asn Asn Tyr Lys Thr Thr Pro
Pro Val Leu Asp Ser 325 330 335Asp Gly Ser Phe Phe Leu Tyr Ser Lys
Leu Thr Val Asp Lys Ser Arg 340 345 350Trp Gln Gln Gly Asn Val Phe
Ser Cys Ser Val Met His Glu Ala Leu 355 360 365His Asn His Tyr Thr
Gln Lys Ser Leu Ser Leu Ser Pro Gly Lys 370 375
38071152DNAArtificial SequenceCTLA4Ig 7atgggtgtac tgctcacaca
gaggacgctg ctcagtctgg tccttgcact cctgtttcca 60agcatggcga gcatggcaat
gcacgtggcc cagcctgctg tggtactggc cagcagccga 120ggcatcgcta
gctttgtgtg tgagtatgca tctccaggca aagccactga ggtccgggtg
180acagtgcttc ggcaggctga cagccaggtg actgaagtct gtgcggcaac
ctacatgatg 240gggaatgagt tgaccttcct agatgattcc atctgcacgg
gcacctccag tggaaatcaa 300gtgaacctca ctatccaagg actgagggcc
atggacacgg gactctacat ctgcaaggtg 360gagctcatgt acccaccgcc
atactacctg ggcataggca acggaaccca gatttatgta 420attgatccag
aaccgtgccc agattctgat caggagccca aatcttctga caaaactcac
480acatccccac cgtccccagc acctgaactc ctgggtggat cgtcagtctt
cctcttcccc 540ccaaaaccca aggacaccct catgatctcc cggacccctg
aggtcacatg cgtggtggtg 600gacgtgagcc acgaagaccc tgaggtcaag
ttcaactggt acgtggacgg cgtggaggtg 660cataatgcca agacaaagcc
gcgggaggag cagtacaaca gcacgtaccg ggtggtcagc 720gtcctcaccg
tcctgcacca ggactggctg aatggcaagg agtacaagtg caaggtctcc
780aacaaagccc tcccagcccc catcgagaaa accatctcca aagccaaagg
gcagccccga 840gaaccacagg tgtacaccct gcccccatcc cgggatgagc
tgaccaagaa ccaggtcagc 900ctgacctgcc tggtcaaagg cttctatccc
agcgacatcg ccgtggagtg ggagagcaat 960gggcagccgg agaacaacta
caagaccacg cctcccgtgc tggactccga cggctccttc 1020ttcctctaca
gcaagctcac cgtggacaag agcaggtggc agcaggggaa cgtcttctca
1080tgctccgtga tgcatgaggc tctgcacaac cactacacgc agaagagcct
ctccctgtct 1140ccgggtaaat ga 11528383PRTArtificial SequenceCTLA4Ig
8Met Gly Val Leu Leu Thr Gln Arg Thr Leu Leu Ser Leu Val Leu Ala1 5
10 15Leu Leu Phe Pro Ser Met Ala Ser Met Ala Met His Val Ala Gln
Pro 20 25 30Ala Val Val Leu Ala Ser Ser Arg Gly Ile Ala Ser Phe Val
Cys Glu 35 40 45Tyr Ala Ser Pro Gly Lys Ala Thr Glu Val Arg Val Thr
Val Leu Arg 50 55 60Gln Ala Asp Ser Gln Val Thr Glu Val Cys Ala Ala
Thr Tyr Met Met65 70 75 80Gly Asn Glu Leu Thr Phe Leu Asp Asp Ser
Ile Cys Thr Gly Thr Ser 85 90 95Ser Gly Asn Gln Val Asn Leu Thr Ile
Gln Gly Leu Arg Ala Met Asp 100 105 110Thr Gly Leu Tyr Ile Cys Lys
Val Glu Leu Met Tyr Pro Pro Pro Tyr 115 120 125Tyr Leu Gly Ile Gly
Asn Gly Thr Gln Ile Tyr Val Ile Asp Pro Glu 130 135 140Pro Cys Pro
Asp Ser Asp Gln Glu Pro Lys Ser Ser Asp Lys Thr His145 150 155
160Thr Ser Pro Pro Ser Pro Ala Pro Glu Leu Leu Gly Gly Ser Ser Val
165 170 175Phe Leu Phe Pro Pro Lys Pro Lys Asp Thr Leu Met Ile Ser
Arg Thr 180 185 190Pro Glu Val Thr Cys Val Val Val Asp Val Ser His
Glu Asp Pro Glu 195 200 205Val Lys Phe Asn Trp Tyr Val Asp Gly Val
Glu Val His Asn Ala Lys 210 215 220Thr Lys Pro Arg Glu Glu Gln Tyr
Asn Ser Thr Tyr Arg Val Val Ser225 230 235 240Val Leu Thr Val Leu
His Gln Asp Trp Leu Asn Gly Lys Glu Tyr Lys 245 250 255Cys Lys Val
Ser Asn Lys Ala Leu Pro Ala Pro Ile Glu Lys Thr Ile 260 265 270Ser
Lys Ala Lys Gly Gln Pro Arg Glu Pro Gln Val Tyr Thr Leu Pro 275 280
285Pro Ser Arg Asp Glu Leu Thr Lys Asn Gln Val Ser Leu Thr Cys Leu
290 295 300Val Lys Gly Phe Tyr Pro Ser Asp Ile Ala Val Glu Trp Glu
Ser Asn305 310 315 320Gly Gln Pro Glu Asn Asn Tyr Lys Thr Thr Pro
Pro Val Leu Asp Ser 325 330 335Asp Gly Ser Phe Phe Leu Tyr Ser Lys
Leu Thr Val Asp Lys Ser Arg 340 345 350Trp Gln Gln Gly Asn Val Phe
Ser Cys Ser Val Met His Glu Ala Leu 355 360 365His Asn His Tyr Thr
Gln Lys Ser Leu Ser Leu Ser Pro Gly Lys 370 375 3809636DNAHomo
SapiensCDS(1)..(636) 9atg ggt gta ctg ctc aca cag agg acg ctg ctc
agt ctg gtc ctt gca 48Met Gly Val Leu Leu Thr Gln Arg Thr Leu Leu
Ser Leu Val Leu Ala -25 -20 -15ctc ctg ttt cca agc atg gcg agc atg
gca atg cac gtg gcc cag cct 96Leu Leu Phe Pro Ser Met Ala Ser Met
Ala Met His Val Ala Gln Pro-10 -5 -1 1 5gct gtg gta ctg gcc agc agc
cga ggc atc gcc agc ttt gtg tgt gag 144Ala Val Val Leu Ala Ser Ser
Arg Gly Ile Ala Ser Phe Val Cys Glu 10 15 20tat gca tct cca ggc aaa
gcc act gag gtc cgg gtg aca gtg ctt cgg 192Tyr Ala Ser Pro Gly Lys
Ala Thr Glu Val Arg Val Thr Val Leu Arg 25 30 35cag gct gac agc cag
gtg act gaa gtc tgt gcg gca acc tac atg atg 240Gln Ala Asp Ser Gln
Val Thr Glu Val Cys Ala Ala Thr Tyr Met Met 40 45 50ggg aat gag ttg
acc ttc cta gat gat tcc atc tgc acg ggc acc tcc 288Gly Asn Glu Leu
Thr Phe Leu Asp Asp Ser Ile Cys Thr Gly Thr Ser55 60 65 70agt gga
aat caa gtg aac ctc act atc caa gga ctg agg gcc atg gac 336Ser Gly
Asn Gln Val Asn Leu Thr Ile Gln Gly Leu Arg Ala Met Asp 75 80 85acg
gga ctc tac atc tgc aag gtg gag ctc atg tac cca ccg cca tac 384Thr
Gly Leu Tyr Ile Cys Lys Val Glu Leu Met Tyr Pro Pro Pro Tyr 90 95
100tac ctg ggc ata ggc aac gga acc cag att tat gta att gat cca gaa
432Tyr Leu Gly Ile Gly Asn Gly Thr Gln Ile Tyr Val Ile Asp Pro Glu
105 110 115ccg tgc cca gat tct gac ttc ctc ctc tgg atc ctt gca gca
gtt agt 480Pro Cys Pro Asp Ser Asp Phe Leu Leu Trp Ile Leu Ala Ala
Val Ser 120 125 130tcg ggg ttg ttt ttt tat agc ttt ctc ctc aca gct
gtt tct ttg agc 528Ser Gly Leu Phe Phe Tyr Ser Phe Leu Leu Thr Ala
Val Ser Leu Ser135 140 145 150aaa atg cta aag aaa aga agc cct ctt
aca aca ggg gtc tat gtg aaa 576Lys Met Leu Lys Lys Arg Ser Pro Leu
Thr Thr Gly Val Tyr Val Lys 155 160 165atg ccc cca aca gag cca gaa
tgt gaa aag caa ttt cag cct tat ttt 624Met Pro Pro Thr Glu Pro Glu
Cys Glu Lys Gln Phe Gln Pro Tyr Phe 170 175 180att ccc atc aat
636Ile Pro Ile Asn 18510212PRTHomo Sapiens 10Met Gly Val Leu Leu
Thr Gln Arg Thr Leu Leu Ser Leu Val Leu Ala -25 -20 -15Leu Leu Phe
Pro Ser Met Ala Ser Met Ala Met His Val Ala Gln Pro-10 -5 -1 1 5Ala
Val Val Leu Ala Ser Ser Arg Gly Ile Ala Ser Phe Val Cys Glu 10 15
20Tyr Ala Ser Pro Gly Lys Ala Thr Glu Val Arg Val Thr Val Leu Arg
25 30 35Gln Ala Asp Ser Gln Val Thr Glu Val Cys Ala Ala Thr Tyr Met
Met 40 45 50Gly Asn Glu Leu Thr Phe Leu Asp Asp Ser Ile Cys Thr Gly
Thr Ser55 60 65 70Ser Gly Asn Gln Val Asn Leu Thr Ile Gln Gly Leu
Arg Ala Met Asp 75 80 85Thr Gly Leu Tyr Ile Cys Lys Val Glu Leu Met
Tyr Pro Pro Pro Tyr 90 95 100Tyr Leu Gly Ile Gly Asn Gly Thr Gln
Ile Tyr Val Ile Asp Pro Glu 105 110 115Pro Cys Pro Asp Ser Asp Phe
Leu Leu Trp Ile Leu Ala Ala Val Ser 120 125 130Ser Gly Leu Phe Phe
Tyr Ser Phe Leu Leu Thr Ala Val Ser Leu Ser135 140 145 150Lys Met
Leu Lys Lys Arg Ser Pro Leu Thr Thr Gly Val Tyr Val Lys 155 160
165Met Pro Pro Thr Glu Pro Glu Cys Glu Lys Gln Phe Gln Pro Tyr Phe
170 175 180Ile Pro Ile Asn 185
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References