U.S. patent application number 11/381705 was filed with the patent office on 2006-11-30 for factor vii or viia polypeptide variants.
This patent application is currently assigned to Maxygen Holdings, Ltd.. Invention is credited to Kim Vilbour Andersen, Jesper Mortensen Haaning.
Application Number | 20060270000 11/381705 |
Document ID | / |
Family ID | 29401388 |
Filed Date | 2006-11-30 |
United States Patent
Application |
20060270000 |
Kind Code |
A1 |
Haaning; Jesper Mortensen ;
et al. |
November 30, 2006 |
Factor VII or VIIa Polypeptide Variants
Abstract
The present invention relates to novel polypeptide variants of
factor VII (FVII) or factor VIIa (FVIIa) polypeptides, where said
variants comprise an amino acid substitution in position 10 and 32
and where said variants further comprise a sugar moiety covalently
attached to an introduced in vivo N-glycosylation site located
outside of the Gla domain. Such polypeptide variants are useful in
therapy, in particular for the treatment of a variety of
coagulation-related disorders, such as trauma.
Inventors: |
Haaning; Jesper Mortensen;
(Birkeroed, DK) ; Andersen; Kim Vilbour;
(Broenshoej, DK) |
Correspondence
Address: |
MAXYGEN, INC.;INTELLECTUAL PROPERTY DEPARTMENT
515 GALVESTON DRIVE
RED WOOD CITY
CA
94063
US
|
Assignee: |
Maxygen Holdings, Ltd.
|
Family ID: |
29401388 |
Appl. No.: |
11/381705 |
Filed: |
May 4, 2006 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
10512754 |
Jul 11, 2005 |
|
|
|
PCT/DK03/00267 |
Apr 29, 2003 |
|
|
|
11381705 |
May 4, 2006 |
|
|
|
60376679 |
Apr 30, 2002 |
|
|
|
Current U.S.
Class: |
435/69.6 ;
435/320.1; 435/325; 514/13.7; 514/14.3; 514/17.7; 514/20.9;
530/383; 536/23.5 |
Current CPC
Class: |
C12Y 304/21021 20130101;
A61P 7/00 20180101; C12N 9/6437 20130101; A61K 38/00 20130101; A61P
7/04 20180101; A61P 17/02 20180101 |
Class at
Publication: |
435/069.6 ;
435/320.1; 435/325; 514/012; 530/383; 536/023.5 |
International
Class: |
A61K 38/38 20060101
A61K038/38; C07K 14/745 20060101 C07K014/745; C07H 21/04 20060101
C07H021/04; C12P 21/04 20060101 C12P021/04 |
Claims
1. A Factor VII (FVII) or Factor VIIa (FVIIa) polypeptide variant
having an amino acid sequence comprising 3-15 amino acid
modifications relative to human Factor VII (hFVII) or human Factor
VIIa (hFVIIa) having the amino acid sequence shown in SEQ ID NO:2,
wherein said amino acid sequence of the variant comprises an amino
acid substitution in position 10 and 32 and wherein a sugar moiety
is covalently attached to an introduced in vivo N-glycosylation
site located outside the Gla domain.
2. The variant according to claim 1, wherein said substitution in
position 10 is P10Q.
3. The variant according to claim 1, wherein said substitution in
position 32 is K32E.
4. The variant according to claim 1, wherein said substitution in
position 10 is P10Q and said substitution in position 32 is
K32E.
5. The variant according to claim 1, wherein said variant comprises
at least one further amino acid modification in the Gla domain.
6-15. (canceled)
16. The variant according to claim 5, wherein said further
modification in the Gla domain comprises an amino acid substitution
in position 34.
17. The variant according to claim 16, wherein a negatively charged
amino acid residue is introduced by substitution in position
34.
18. The variant according to claim 17, wherein said substitution is
A34E.
19. The variant according to claim 18, wherein said variant
comprises the substitutions P10Q+K32E+A34E.
20-25. (canceled)
26. The variant according to claim 1, wherein said in vivo
N-glycosylation site is introduced by substitution.
27-28. (canceled)
29. The variant according to claim 26, wherein said in vivo
N-glycosylation site is introduced by a substitution selected from
the group consisting of A51N, G58N, T106N, K109N, G124N,
K143N+N145T, A175T, I205S, I205T, V253N, T267N, T267N+S269T,
S314N+K316S, S314N+K316T, R315N+V317S, R315N+V317T, K316N+G318S,
K316N+G318T, G318N, D334N and combinations thereof.
30. The variant according to claim 29, wherein said in vivo
N-glycosylation site is introduced by a substitution selected from
the group consisting of A51N, G58N, T106N, K109N, G124N,
K143N+N145T, A175T, I205T, V253N, T267N+S269T, S314N+K316T,
R315N+V317T, K316N+G318T, G318N, D334N and combinations
thereof.
31. The variant according to claim 30, wherein said in vivo
N-glycosylation site is introduced by a substitution selected from
the group consisting of T106N, A175T, I205T, V253N, T267N+S269T and
combinations thereof.
32. The variant according to claim 16, wherein one in vivo
N-glycosylation site has been introduced by substitution.
33. The variant according to claim 16, wherein two or more in vivo
N-glycosylation sites have been introduced by substitution.
34-40. (canceled)
41. The variant according to claim 1, wherein said variant is in
its activated form.
42. The variant according to claim 1, wherein said variant, in its
activated form, has at least 10% of the amidolytic activity of
rhFVIIa when assayed in the "Amidolytic Assay" described
herein.
43. The variant according to claim 1, wherein said variant, in its
activated form, has at least 10% of the clotting activity of
rhFVIIa when assayed in the "Clotting Assay" described herein.
44. A nucleotide sequence encoding the variant of claim 1.
45. An expression vector comprising the nucleotide sequence of
claim 44.
46. A host cell comprising the nucleotide sequence of claim 44.
47. The host cell according to claim 46, wherein said host cell is
a gammacarboxylating cell capable of in vivo glycosylation.
48. A pharmaceutical composition comprising the variant of claim 1,
and a pharmaceutical acceptable carrier or excipient.
49.-54. (canceled)
55. A method for treating a mammal having a disease or a disorder
wherein clot formation is desirable, comprising administering to a
mammal in need thereof an effective amount of the pharmaceutical
composition of claim 48.
56. The method according to claim 55, wherein said disease or
disorder is selected from the group consisting of hemorrhage,
including brain hemorrhage, severe uncontrolled bleeding, such as
trauma, bleeding in patients undergoing living transplantations,
bleeding in patients undergoing resection and variceal
bleedings.
57-59. (canceled)
Description
FIELD OF THE INVENTION
[0001] The present invention relates to novel polypeptide variants
of factor VII (FVII) or factor VIIa (FVIIa) polypeptides, where
said variants comprise an amino acid substitution in position 10
and 32 and where said variants further comprise a sugar moiety
covalently attached to an introduced in vivo N-glycosylation
site.
[0002] The present invention also relates to use of such
polypeptide variants in therapy, in particular for the treatment of
a variety of coagulation-related disorders.
BACKGROUND OF THE INVENTION
[0003] Blood coagulation is a process consisting of a complex
interaction of various blood components (or factors) that
eventually results in a fibrin clot. Generally, the blood
components participating in what has been referred to as the
"coagulation cascade" are proenzymes or zymogens, i.e.
enzymatically inactive proteins that are converted into an active
form by the action of an activator. One of these coagulation
factors is FVII.
[0004] FVII is a vitamin K-dependent plasma protein synthesized in
the liver and secreted into the blood as a single-chain
glycoprotein with a molecular weight of 53 kDa (Broze &
Majerus, J. Biol. Chem 1980; 255:1242-1247). The FVII zymogen is
converted into an activated form (FVIIa) by proteolytic cleavage at
a single site, R152-I153, resulting in two chains linked by a
single disulfide bridge. FVIIa in complex with tissue factor (FVIIa
complex) is able to convert both factor IX and factor X into their
activated forms, followed by reactions leading to rapid thrombin
production and fibrin formation (Osterud & Rapaport, Proc Natl
Acad Sci USA 1977; 74:5260-5264).
[0005] FVII undergoes post-translational modifications, including
vitamin K-dependent carboxylation resulting in ten
.gamma.-carboxyglutamic acid residues in the N-terminal region of
the molecule. Thus, residue number 6, 7, 14, 16, 19, 20, 25, 26, 29
and 35 shown in SEQ ID NO:2 are .gamma.-carboxyglutamic acids
residues in the Gla domain important for FVII activity. Other
post-translational modifications include sugar moiety attachment at
two naturally occurring N-glycosylation sites at position 145 and
322, respectively, and at two naturally occurring O-glycosylation
sites at position 52 and 60, respectively.
[0006] The gene coding for human FVII (hFVII) has been mapped to
chromosome 13 at q34-qter 9 (de Grouchy et al., Hum Genet 1984;
66:230-233). It contains nine exons and spans 12.8 Kb (O'Hara et
al., Proc Natl Acad Sci USA 1987; 84:5158-5162). The gene
organisation and protein structure of FVII are similar to those of
other vitamin K-dependent procoagulant proteins, with exons 1a and
1b encoding for signal sequence; exon 2 the propeptide and Gla
domain; exon 3 a short hydrophobic region; exons 4 and 5 the
epidermal growth factor-like domains; and exon 6 through 8 the
serine protease catalytic domain (Yoshitake et al., Biochemistry
1985; 24: 3736-3750).
[0007] Reports exist on experimental three-dimensional structures
of hFVIIa (Pike et al., PNAS. U.S.A., 1999; 96:8925-30 and
Kemball-Cook et al., J. Struct. Biol, 1999; 127:213-223); of hFVIIa
in complex with soluble tissue factor using X-ray crystallographic
methods (Banner et al., Nature, 1996; 380:41 and Zhang et al., J.
Mol. Biol, 1999; 285: 2089); and of smaller fragments of hFVII
(Muranyi et al., Biochemistry, 1998; 37:10605 and Kao et al.,
Bio-chemistry, 1999; 38:7097).
[0008] Some protein-engineered variants of FVII have been reported.
See, e.g., Dickinson & Ruf, J Bio Chem, 1997; 272:19875-19879,
Kemball-Cook et al., J Biol Chem, 1998; 273:8516-8521, Bharadwaj et
al., J Biol Chem, 1996; 271:30685-30691, Ruf et al., Biochemistry,
1999; 38:1957-1966; WO 99/20767; WO 00/11416; WO 02/22776; WO
02/38162; WO 01/83725; WO 01/58935; U.S. Pat. No. 5,580,560.
[0009] Reports exist on expression of FVII in BHK or other
mammalian cells (WO 92/15686, WO 91/11514 and WO 88/10295) and
co-expression of FVII and kex2 endoprotease in eukaryotic cells (WO
00/28065).
[0010] Commercial preparations of human recombinant FVIIa are sold
as NovoSeven.RTM.. NovoSeven.RTM. is indicated for the treatment of
bleeding episodes in hemophilia A or B patients. NovoSeven.RTM. is
the only rhFVIIa for effective and reliable treatment of bleeding
episodes available on the market.
[0011] An inactive form of FVII in which arginine 152 and/or
isoleucine 153 is/are modified has been reported in WO91/1154.
These amino acids are located at the activation site. WO 96/12800
describes inactivation of FVIIa by a serine proteinase inhibitor;
inactivation by carbamylation of FVIIa at the .alpha.-amino acid
group I153 has been described by Petersen et al., Eur J Biochem,
1999; 261:124-129. The inactivated form is capable of competing
with wild-type FVII or FVIIa for binding to tissue factor and
inhibiting clotting activity. The inactivated form of FVIIa is
suggested to be used for treatment of patients being in
hypercoagulable states, such as patients with sepsis, in risk of
myocardial infarction or of thrombotic stroke.
[0012] A circulating rhFVIIa half-life of 2.3 hours was reported in
"Summary Basis for Approval for NovoSeven.RTM.", FDA reference
number 96-0597. Relatively high doses and frequent administration
are necessary to reach and sustain the desired therapeutic or
prophylactic effect. As a consequence adequate dose regulation is
difficult to obtain and the need of frequent intravenous
administrations imposes restrictions on the patient's way of
living.
[0013] In connection with treatment of uncontrolled bleedings, such
as trauma, it is believed that factor VIIa is capable of activating
factor X to factor Xa without binding to tissue factor, and this
activation reaction is believed to occur primarily on activated
blood platelets (Hedner et al. Blood Coagulation &
Fibrinolysis, 2000; 11; 107-111). However, hFVIIa or rhFVIIa has a
low activity towards factor X in the absence of tissue factor and,
consequently, treatment of uncontrolled bleeding, for example in
trauma patients, requires relatively high and multiple doses of
hFVIIa or rhFVIIa. Therefore, in order to treat uncontrolled
bleedings more efficiently (to minimize blood loss) there is need
for improved FVIIa molecules, which possess a high activity toward
factor X in the absence of tissue factor. Such improved FVIIa
molecules will exhibit a lowered clotting time (or faster action)
as compared to rhFVIIa when administered in connection with
uncontrolled bleedings.
[0014] A molecule with a longer circulation half-life would
decrease the number of necessary administrations. Given the
association of current the rhFVIIa product with frequent
injections, and the potential for obtaining more optimal
therapeutic FVIIa levels with concomitant enhanced therapeutic
effect, there is a clear need for improved FVII- or FVIIa-like
molecules.
[0015] One way to increase the circulation half-life of a protein
is to ensure that renal clearance of the protein is reduced. This
may be achieved by conjugating the protein to a chemical moiety,
which is capable of conferring reduced renal clearance to the
protein.
[0016] Furthermore, attachment of a chemical moiety to the protein
or substitution of amino acids exposed to proteolysis may
effectively block a proteolytic enzyme from contact leading to
proteolytic degradation of the protein. Polyethylene glycol (PEG)
is one such chemical moiety that has been used in the preparation
of therapeutic protein products. WO 98/32466 suggests that FVII,
among many other proteins, may be PEGylated but does not contain
any further information in this respect. WO 01/58935 discloses a
new strategy for developing FVII or FVIIa molecules having inter
alia an increased half-life.
[0017] As indicated above, another problem in current rhFVIIa
treatment is the relative instability of the molecule with respect
to proteolytic degradation. Proteolytic degradation is a major
obstacle for obtaining a preparation in solution as opposed to a
lyophilized product. The advantage of obtaining a stable soluble
preparation lies in easier handling for the patient, and, in the
case of emergencies, quicker action, which potentially can become
life saving. Attempts to prevent proteolytic degradation by site
directed mutagenesis at major proteolytic sites have been disclosed
in WO 88/10295.
[0018] One object of the present invention is to provide improved
FVII or FVIIa molecules (FVII or FVIIa variants) with a longer
circulation half-life (thereby decreasing the number of necessary
administrations) and which are capable of activating factor X to
factor Xa (without binding to tissue factor) more efficiently than
hFVIIa or rhFVIIa (thereby being able to treat uncontrolled
bleadings, such as a trauma, more efficiently).
[0019] Another object of the present invention is to provide
improved FVII or FVII molecules (FVII or FVIIa variants) with an
increased bioavailability (such as an increased Area Under the
Curve as compared to rhFVIIa when administered intravenously) and
which are capable of activating factor X to factor Xa (without
binding to tissue factor) more efficiently than hFVIIa or rhFVIIa
(thereby being able to treat uncontrolled bleadings, such as a
trauma, more efficiently).
[0020] These objects are met by the FVII or FVIIa variants provided
herein.
BRIEF DISCLOSURE OF THE INVENTION
[0021] In its broadest aspect the present invention relates to a
FVII or FVIIa polypeptide variant having an amino acid sequence
comprising 3-15 amino acid modifications relative to hFVII or
hFVIIa having the amino acid sequence shown in SEQ ID NO:2, wherein
said amino acid sequence of the variant comprises an amino acid
substitution in position 10 and 32 and wherein a sugar moiety is
covalently attached to an introduced in vivo N-glycosylation site
located outside the Gla domain.
[0022] Another aspect of the invention relates to a nucleotide
sequence encoding the polypeptide variant of the invention.
[0023] In a further aspect the invention relates to an expression
vector comprising the nucleotide sequence of the invention.
[0024] In a still further aspect the invention relates to a host
cell comprising the nucleotide sequence of the invention or the
expression vector of the invention.
[0025] In an even further aspect the invention relates to a
pharmaceutical composition comprising the polypeptide variant of
the invention, and a pharmaceutical acceptable carrier or
excipient.
[0026] Still another aspect of the invention relates to the
polypeptide variant of the invention, or the pharmaceutical
composition of the invention, for use as a medicament.
[0027] Further aspects of the present invention will be apparent
from the below description as well as from the appended claims.
DETAILED DISCLOSURE OF THE INVENTION
Definitions
[0028] In the context of the present application and invention the
following definitions apply:
[0029] The term "conjugate" (or interchangeably "conjugated
polypeptide") is intended to indicate a heterogeneous (in the sense
of composite or chimeric) molecule formed by the covalent
attachment of one or more polypeptide(s) to one or more
non-polypeptide moieties such as polymer molecules, lipophilic
compounds, sugar moieties or organic derivatizing agents.
Preferably, the conjugate is soluble at relevant concentrations and
conditions, i.e. soluble in physiological fluids such as blood.
Examples of conjugated polypeptides of the invention include
glycosylated and/or PEGylated polypeptides.
[0030] The term "covalent attachment" or "covalently attached"
means that the polypeptide variant and the non-polypeptide moiety
are either directly covalently joined to one another, or else are
indirectly covalently joined to one another through an intervening
moiety or moieties, such as a bridge, spacer, or linkage moiety or
moieties.
[0031] The term "non-polypeptide moiety" is intended to mean a
molecule, different from a peptide polymer composed of amino acid
monomers and linked together by peptide bonds, which molecule is
capable of conjugating to an attachment group of the polypeptide
variant of the invention. Preferred examples of such molecules
include polymer molecules, sugar moieties, lipophilic compounds or
organic derivatizing agents. When used in the context of a
conjugated variant of the invention it will be understood that the
non-polypeptide moiety is linked to the polypeptide part of the
conjugated variant through an attachment group of the polypeptide.
As explained above, the non-polypeptide moiety can be directly
covalently joined to the attachment group or it can be indirectly
covalently joined to the attachment group through an intervening
moiety or moieties, such as a bridge spacer or linker moiety or
moieties.
[0032] A "polymer molecule" is a molecule formed by covalent
linkage of two or more monomers, wherein none of the monomers is an
amino acid residue, except where the polymer is human albumin or
another abundant plasma protein. The term "polymer" may be used
interchangeably with the term "polymer molecule". The term is also
intended to cover carbohydrate molecules attached by in vitro
glycosylation, i.e. a synthetic glycosylation performed in vitro
normally involving covalently linking a carbohydrate molecule to an
attachment group of the polypeptide variant, optionally using a
cross-linking agent. In vitro glycosylation is discussed in detail
further below.
[0033] The term "sugar moiety" is intended to indicate a
carbohydrate-containing molecule comprising one or more
monosaccharide residues, capable of being attached to the
polypeptide variant (to produce a polypeptide variant conjugate in
the form of a glycosylated polypeptide variant) by way of in vivo
glycosylation. The term "in vivo glycosylation" is intended to mean
any attachment of a sugar moiety occurring in vivo, i.e. during
posttranslational processing in a glycosylating cell used for
expression of the polypeptide variant, e.g. by way of N-linked and
O-linked glycosylation. The exact oligosaccharide structure
depends, to a large extent, on the glycosylating organism in
question.
[0034] An "N-glycosylation site" has the sequence N-X-S/T/C,
wherein X is any amino acid residue except proline, N is asparagine
and S/T/C is either serine, threonine or cysteine, preferably
serine or threonine, and most preferably threonine. Preferably, the
amino acid residue in position +3 relative to the asparagines
residue is not a proline residue.
[0035] An "O-glycosylation site" is the OH-group of a serine or
threonine residue.
[0036] The term "attachment group" is intended to indicate a
functional group of the polypeptide variant, in particular of an
amino acid residue thereof or a carbohydrate moiety, capable of
attaching a non-polypeptide moiety such as a polymer molecule, a
lipophilic molecule, a sugar moiety or an organic derivatizing
agent. Useful attachment groups and their matching non-polypeptide
moieties are apparent from the table below. TABLE-US-00001
Conjugation Attachment Examples of non- method/-Activated group
Amino acid polypeptide moiety PEG Reference --NH.sub.2 N-terminal,
Polymer, e.g. PEG, mPEG-SPA Shearwater Inc. Lys with amide or imine
Tresylated mPEG Delgado et al, critical group reviews in
Therapeutic Drug Carrier Systems 9(3, 4): 249-304 (1992) --COOH
C-terminal, Polymer, e.g. PEG, mPEG-Hz Shearwater Inc. Asp, Glu
with ester or amide group Carbohydrate In vitro coupling moiety
--SH Cys Polymer, e.g. PEG, PEG-vinylsulphone Shearwater Inc. with
disulfide, PEG-maleimide Delgado et al, critical maleimide or
vinylsulfone reviews in group Therapeutic Drug Carbohydrate In
vitro coupling Carrier Systems moiety 9(3, 4): 249-304 (1992) --OH
Ser, Thr, Sugar moiety In vivo O-linked Lys, OH-- PEG with ester,
glycosylation ether, carbamate, carbonate --CONH.sub.2 Asn as part
Sugar moiety In vivo N- of an N- Polymer, e.g. PEG glycosylation
glycosylation site Aromatic Phe, Tyr, Carbohydrate In vitro
coupling residue Trp moiety --CONH.sub.2 Gln Carbohydrate In vitro
coupling Yan and Wold, moiety Biochemistry, 1984, Jul 31; 23(16):
3759-65 Aldehyde Oxidized Polymer, e.g. PEG, PEGylation Andresz et
al., 1978, Ketone oligosaccharide PEG-hydrazide Makromol. Chem.
179: 301, WO 92/16555, WO 00/23114 Guanidino Arg Carbohydrate In
vitro coupling Lundblad and Noyes, moiety Chimical Reagents for
Protein Modification, CRC Press Inc., Florida, USA Imidazole His
Carbohydrate In vitro coupling As for guanidine ring moiety
[0037] For in vivo N-glycosylation, the term "attachment group" is
used in an unconventional way to indicate the amino acid residues
constituting a N-glycosylation site (with the sequence N-X-S/T/C,
wherein X is any amino acid residue except proline, N is asparagine
and S/T/C is either serine, threonine or cysteine, preferably
serine or threonine, and most preferably threonine). Although the
asparagine residue of the N-glycosylation site is the one to which
the sugar moiety is attached during glycosylation, such attachment
cannot be achieved unless the other amino acid residues of the
N-glycosylation site is present.
[0038] Accordingly, when the non-polypeptide moiety is a sugar
moiety and the conjugation is to be achieved by in vivo
N-glycosylation, the term "amino acid residue comprising an
attachment group for a non-polypeptide moiety" as used in
connection with alterations of the amino acid sequence of the
polypeptide is to be understood as meaning that one or more amino
acid residues constituting an in vivo N-glycosylation site are to
be altered in such a manner that a functional in vivo
N-glycosylation site is introduced into the amino acid
sequence.
[0039] In the present application, amino acid names and atom names
(e.g. CA, CB, CD, CG, SG, NZ, N, O, C, etc) are used as defined by
the Protein DataBank (PDB) (www.pdb.org) based on the IUPAC
nomenclature (IUPAC Nomenclature and Symbolism for Amino Acids and
Peptides (residue names, atom names, etc.), Eur. J. Biochem., 138,
9-37 (1984) together with their corrections in Eur. J. Biochem.,
152, 1 (1985)).
[0040] The term "amino acid residue" is intended to indicate an
amino acid residue contained in the group consisting of alanine
(Ala or A), cysteine (Cys or C), aspartic acid (Asp or D), glutamic
acid (Glu or E), phenylalanine (Phe or F), glycine (Gly or G),
histidine (His or H), isoleucine (Ile or I), lysine (Lys or K),
leucine (Leu or L), methionine (Met or M), asparagine (Asn or N),
proline (Pro or P), glutamine (Gln or Q), arginine (Arg or R),
serine (Ser or S), threonine (Thr or T), valine (Val or V),
tryptophan (Trp or W), and tyrosine (Tyr or Y) residues.
[0041] The terminology used for identifying amino acid positions is
illustrated as follows: I205 indicates that position 205 is
occupied by an isoleucine residue in the amino acid sequence shown
in SEQ ID NO:2. I205T indicates that the isoleucine residue of
position 205 has been substituted with a threonine residue.
Alternative substitutions are indicated with a "/", e.g. I205S/T
means an amino acid sequence in which isoleucine in position 205 is
substituted with either serine or threonine. Multiple substitutions
are indicated with a "+", e.g. K143N+N145T means a substitution of
the lysine residue in position 143 with an asparagine residue and a
substitution of the asparagine residue in position 145 with a
threonine residue. Insertion of an additional amino acid residue is
indicated in the following way: Insertion of a tyrosine residue
after A3 (i.e. in position 4) is indicated by A3AY (leading to
insertion of a tyrosine residue in position 4). A deletion of an
amino acid residue is indicated by an asterix. For example,
deletion of a valine residue in position 172 is indicated by V172*.
Simultaneous insertion and substitution are indicated in the
following way: Substitution of an alanine residue in position 175
with a threonine residue followed by insertion of a leucine residue
after position 175 is indicated A175TL.
[0042] Unless otherwise indicated, the numbering of amino acid
residues made herein is made relative to the amino acid sequence of
the hFVII/hFVIIa polypeptide (SEQ ID NO:2).
[0043] The term "differs from" as used in connection with specific
mutations is intended to allow for additional differences being
present apart from the specified amino acid difference. For
instance, in addition to the introduction of in vivo
N-glycosylation sites (located outside the Gla domain), the
polypeptide may comprise other modifications that are not related
to introduction of such amino acid residues. In a similar way, in
addition to the modifications performed in the Gla domain aiming at
increasing the phospholipid membrane binding affinity, the
polypeptide may contain other modifications that are not
necessarily related to this effect. Thus, in addition to the amino
acid modifications disclosed herein, it will be understood that the
amino acid sequence of the polypeptide variant of the invention
may, if desired, contain other alterations, i.e. other
substitutions, insertions or deletions. These may, for example,
include truncation of the N- and/or C-terminus by one or more amino
acid residues (e.g. by 1-10 amino acid residues), or addition of
one or more extra residues at the N- and/or C-terminus, e.g.
addition of a methionine residue at the N-terminus or introduction
of a cysteine residue near or at the C-terminus, as well as
"conservative amino acid substitutions", i.e. substitutions
performed within groups of amino acids with similar
characteristics, e.g. small amino acids, acidic amino acids, polar
amino acids, basic amino acids, hydrophobic amino acids and
aromatic amino acids.
[0044] Examples of such conservative substitutions are shown in the
below table. TABLE-US-00002 1 Alanine (A) Glycine (G) Serine (S)
Threonine (T) 2 Aspartic acid (D) Glutamic acid (E) 3 Asparagine
(N) Glutamine (Q) 4 Arginine (R) Histidine (H) Lysine (K) 5
Isoleucine (I) Leucine (L) Methionine (M) Valine (V) 6
Phenylalanine (F) Tyrosine (Y) Tryptophan (W)
[0045] Still other examples of additional modifications are
disclosed in the section entitled "Other modifications outside the
Gla domain" below.
[0046] The term "nucleotide sequence" is intended to indicate a
consecutive stretch of two or more nucleotide molecules. The
nucleotide sequence may be of genomic, cDNA, RNA, semisynthetic,
synthetic origin, or any combinations thereof.
[0047] The term "polymerase chain reaction" or "PCR" generally
refers to a method for amplification of a desired nucleotide
sequence in vitro, as described, for example, in U.S. Pat. No.
4,683,195. In general, the PCR method involves repeated cycles of
primer extension synthesis, using oligonucleotide primers capable
of hybridising preferentially to a template nucleic acid.
[0048] The term "vector" refers to a plasmid or other nucleotide
sequences that are capable of replicating within a host cell or
being integrated into the host cell genome, and as such, are useful
for performing different functions in conjunction with compatible
host cells (a vector-host system): to facilitate the cloning of the
nucleotide sequence, i.e. to produce usable quantities of the
sequence, to direct the expression of the gene product encoded by
the sequence and to integrate the nucleotide sequence into the
genome of the host cell. The vector will contain different
components depending upon the function it is to perform.
[0049] "Cell", "host cell", "cell line" and "cell culture" are used
interchangeably herein and all such terms should be understood to
include progeny resulting from growth or culturing of a cell.
[0050] "Transformation" and "transfection" are used interchangeably
to refer to the process of introducing DNA into a cell.
[0051] "Operably linked" refers to the covalent joining of two or
more nucleotide sequences, by means of enzymatic ligation or
otherwise, in a configuration relative to one another such that the
normal function of the sequences can be performed. For example, the
nucleotide sequence encoding a presequence or secretory leader is
operably linked to a nucleotide sequence coding for a polypeptide
if it is expressed as a preprotein that participates in the
secretion of the polypeptide: a promoter or enhancer is operably
linked to a coding sequence if it affects the transcription of the
sequence; a ribosome binding site is operably linked to a coding
sequence if it is positioned so as to facilitate translation.
Generally, "operably linked" means that the nucleotide sequences
being linked are contiguous and, in the case of a secretory leader,
contiguous and in reading phase. Linking is accomplished by
ligation at convenient restriction sites. If such sites do not
exist, then synthetic oligonucleotide adaptors or linkers are used,
in conjunction with standard recombinant DNA methods.
[0052] In the context of the present invention the terms
"modification" or "amino acid modification" is intended to cover
replacement of an amino acid side chain, substitution of an amino
acid residue, deletion of an amino acid residue and/or insertion of
an amino acid residue.
[0053] The terms "mutation" and "substitution" are used
interchangeably herein.
[0054] The term "introduce" refers to introduction of an amino acid
residue by substitution of an existing amino acid residue or,
alternatively, by insertion of an additional amino acid
residue.
[0055] The term "remove" refers to removal of an amino acid residue
by substitution of the amino acid residue to be removed by another
amino acid residue or, alternatively, by deletion (without
substitution) of the amino acid residue to be removed
[0056] The term "FVII" or "FVII polypeptide" refers to a FVII
molecule provided in single chain form. One example of a FVII
polypeptide is wild-type human FVII (hFVII) shown in SEQ ID NO:2.
It should be understood, however, that the term "FVII polypeptide"
also covers hFVII-like molecules, such as fragments or variants of
SEQ ID NO:2, in particular variants where the sequence comprises at
least one, such as 1-15, e.g., 1-10, amino acid modifications as
compared to SEQ ID NO:2.
[0057] The term "FVIIa" or "FVIIa polypeptide" refers to a FVIIa
molecule provided in its activated two-chain form. When the amino
acid sequence of SEQ ID NO:2 is used to describe the amino acid
sequence of FVIIa it will be understood that the peptide bond
between R152 and I153 of the single-chain form has been cleaved,
and that one of the chains comprises amino acid residues 1-152, the
other chain amino acid residues 153-406.
[0058] The terms "rFVII" and "rFVIIa" refer to FVII and FVIIa
polypeptides produced by recombinant techniques.
[0059] The terms "hFVII" and "hFVIIa" refer to human wild-type FVII
and FVIIa, respectively, having the amino acid sequence shown in
SEQ ID NO:2
[0060] The terms "rhFVII" and "rhFVIIa" refer to human wild-type
FVII and FVIIa, having the amino acid sequence shown in SEQ ID
NO:2, produced by recombinant means. An example of rhFVIIa is
NovoSeven.RTM..
[0061] When used herein, the term "Gla domain" is intended to cover
amino acid residues no. 1 to 45 of SEQ ID NO:2.
[0062] Accordingly, the term "located outside the Gla domain"
covers amino acid residue no. 46-406 of SEQ ID NO:2.
[0063] The abbreviations "TF" and "TFPI" mean Tissue Factor and
Tissue Factor Pathway Inhibitor, respectively.
[0064] The term "protease domain" is used about residues 153-406
counted from the N-terminus.
[0065] The term "catalytic site" is used to mean the catalytic
triad consisting of S344, D242 and H193 of the polypeptide
variant.
[0066] The term "parent" is intended to indicate the molecule to be
modified/improved in accordance with the present invention.
Although the parent polypeptide to be modified by the present
invention may be any FVII or FVIIa polypeptide, and thus be derived
from any origin, e.g. a non-human mammalian origin, it is preferred
that the parent polypeptide is hFVII or hFVIIa
[0067] A "variant" is a polypeptide, which differs in one or more
amino acid residues from its parent polypeptide, normally in 3-15
amino acid residues (e.g. in 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13,
14 or 15 amino acid residues), such as in 3-10 amino acid residues,
e.g. in 3-8 or 3-5 amino acid residues. In other words, a "variant"
typically contains 3-15 amino acid modifications (for example 3, 4,
5, 6, 7, 8, 9, 10, 11, 12, 13, 14 or 15 amino acid modifications),
such as 3-10 amino acid modifications, e.g. 3-8 or 3-5 amino acid
modifications relative to the parent polypeptide. In the present
context, the term "modification" encompasses insertions, deletions,
substitutions and combinations thereof. It will be understood that
a polypeptide variant according to the present invention will be
modified in at least three positions, namely in at least position
10 and 32 (located in the Gla domain) and in at least one position
located outside the Gla domain, where said at least one
modification creates an in vivo N-glycosylation site.
[0068] The term "clotting activity" is used to mean the activity
measured in the "Clotting Assay" described herein. In order to
exhibit "clotting activity" a variant of the invention, in its
activated form, should have at least 10% of the clotting acitivty
of rhFVIIa when assayed in the "Clotting Assay" described herein.
In a preferred embodiment of the invention the variant, in its
activated form, has at least 20% of the clotting activity of
rhFVIIa, such as at least 30%, e.g. at least 40%, more preferably
at least 50%, such as at least 60%, e.g. at least 70%, even more
preferably at least 80%, such as at least 90% of the clotting
activity of rhFVIIa when assayed in the "Clotting Assay" described
herein. In an interesting embodiment the variant, in its activated
form, has substantially the same clotting activity as rhFVIIs, such
as a clotting activity of 75-125% of the clotting acitivity of
rhFVIIa.
[0069] The term "amidolytic activity" is used to mean the activity
measured in the "Amidolytic Assay" described herein. In order to
exhibit "amidolytic activity" a variant of the invention, in its
activated form, should have at least 10% of the amidolytic acitivty
of rhFVIIa when assayed in the "Amidolytic Assay" described herein.
In a preferred embodiment of the invention the variant, in its
activated form, has at least 20% of the amidolytic activity of
rhFVIIa, such as at least 30%, e.g. at least 40%, more preferably
at least 50%, such as at least 60%, e.g. at least 70%, even more
preferably at least 80%, such as at least 90% of the amidolytic
activity of rhFVIIa when assayed in the "Amidolytic Assay"
described herein. In an interesting embodiment the variant, in its
activated form, has substantially the same amidolytic activity as
rhFVIIs, such as an amidolytic activity of 75-125% of the
amidolytic acitivity of rhFVIIa.
[0070] In the present context, the term "activity" is also used in
connection with the variants capability of activating FX to FXa.
This activity is also denoted "FX activation activity" or "FXa
generation activity".
[0071] The term "increased FX activiation activity" or "increased
FXa generation activity" is used to indicate that a variant of the
invention, in its activated form, has a statistically signifycantly
increased capability to activate FX to FXa as compared to rhFVIIa
or. To what extent a variant of the invention (in its activated
form) has an increased FX activation activity may conveniently be
determined in the "TF-independent Factor X Activation Assay"
described herein.
[0072] The term "stronger clot" or "increased clot strength" is
used to indicate that the strength of the clot generated by the
polypeptide variant is statistically significantly increased
relative to that generated by rhFVIIa as determined under
comparable conditions. This effect may be determined as the Area
Under the Curve (AUC.sub.throm) generated by the variant of the
invention, in its activated form, when assayed in the "Thrombogram
Assay" disclosed herein. In a similar way, the term "increased
AUC.sub.throm" is used to indicate that the Area Under the Curve
generated by the variant (in its activated form) is statistically
significantly increased relative to that generated by rhFVIIa as
determined under comparable conditions and when measured in the
"Thrombogram Assay" described herein
[0073] The term "T.sub.max" is used about the time it takes to
obtain the maximum thrombin activity level in the "Thrombogram
Assay".
[0074] The term "immunogenicity" as used in connection with a given
substance is intended to indicate the ability of the substance to
induce a response from the immune system. The immune response may
be a cell or antibody mediated response (see, e.g., Roitt:
Essential Immunology (8.sup.th Edition, Blackwell) for further
definition of immunogenicity). Normally, reduced antibody
reactivity will be an indication of reduced immunogenicity. The
reduced immunogenicity may be determined by use of any suitable
method known in the art, e.g. in vivo or in vitro.
[0075] The term "functional in vivo half-life" is used in its
normal meaning, i.e. the time at which 50% of the biological
activity of the polypeptide is still present in the body/target
organ, or the time at which the activity of the polypeptide is 50%
of the initial value.
[0076] As an alternative to determining functional in vivo
half-life, "serum half-life" may be determined, i.e. the time at
which 50% of the polypeptide circulates in the plasma or
bloodstream prior to being cleared. Determination of serum
half-life is often more simple than determining the functional in
vivo half-life and the magnitude of serum half-life is usually a
good indication of the magnitude of functional in vivo half-life.
Alternatively terms to serum half-life include "plasma half-life",
"circulating half-life", "serum clearance", "plasma clearance" and
"clearance half-life". The polypeptide is cleared by the action of
one or more of the reticuloendothelial systems (RES), kidney,
spleen or liver, by tissue factor, SEC receptor or other receptor
mediated elimination, or by specific or unspecific proteolysis.
Normally, clearance depends on size (relative to the cutoff for
glomerular filtration), charge, attached carbohydrate chains, and
the presence of cellular receptors for the protein. The
functionality to be retained is normally selected from
procoagulant, proteolytic or receptor binding activity. The
functional in vivo half-life and the serum half-life may be
determined by any suitable method known in the art.
[0077] The term "increased" as used about the functional in vivo
half-life or serum half-life is used to indicate that the relevant
half-life of the polypeptide variant is statistically significantly
increased relative to that of rhFVIIa as determined under
comparable conditions (typically determined in an experimental
animal, such as rats, rabbits, pigs or monkeys).
[0078] The term "AUC.sub.iv" or "Area Under the Curve when
administered intravenously" is used in its normal meaning, i.e. as
the area under the activity in serum-time curve, where the
polypeptide variant has been administered intravenously, in
particular when administered intravenously in rats. Typically, the
activity measured is the "clotting activity" as defined
hereinbefore. Once the experimental activity-time points have been
determined, the AUC.sub.iv may conveniently be calculated by a
computer program, such as GraphPad Prism 3.01.
[0079] It will be understood that in order to make a direct
comparison between the AUC.sub.iv-values of different molecules
(e.g. between the variants of the invention and a reference
molecule such as rhFVIIa) the same amount of activity should be
administered. Consequently, the AUC.sub.iv-values are typically
normalized (i.e. corrected for differences in the injected dose)
and expressed as AUC.sub.iv/dose administered.
[0080] The term "reduced sensitivity to proteolytic degradation" is
primarily intended to mean that the polypeptide variant has reduced
sensitivity to proteolytic degradation in comparison to hFVIIa or
rhFVIIa as determined under comparable conditions. Preferably, the
proteolytic degradation is reduced by at least 10% (e.g. by 10-25%
or by 10-50%), such as at least 25% (e.g. by 25-50%, by 25-75% or
by 25-100%), more preferably by at least 35%, such as at least 50%,
(e.g. by 50-75% or by 50-100%) even more preferably by at least
60%, such as by at least 75% (e.g. by 75-100%) or even at least
90%. Most preferably, the proteolytic degradation is reduced by at
least 100%.
[0081] The term "renal clearance" is used in its normal meaning to
indicate any clearance taking place by the kidneys, e.g. by
glomerular filtration, tubular excretion or degradation in the
tubular cells. Renal clearance depends on physical characteristics
of the polypeptide, including size (diameter), hydrodynamic volume,
symmetry, shape/rigidity, and charge. Normally, a molecular weight
of about 67 kDa is considered to be a cut-off-value for renal
clearance. Renal clearance may be established by any suitable
assay, e.g. an established in vivo assay. Typically, renal
clearance is determined by administering a labelled (e.g.
radiolabelled or fluorescence labelled) polypeptide to a patient
and measuring the label activity in urine collected from the
patient. Reduced renal clearance is determined relative to a
corresponding reference polypeptide, e.g. rhFVIIa, under comparable
conditions. Preferably, the renal clearance rate of the polypeptide
variant is reduced by at least 50%, preferably by at least 75%, and
most preferably by at least 90% compared to rhFVIIa.
[0082] The terms "at least 25% of its side chain exposed to the
surface of the molecule" and "at least 50% of its side chain
exposed to the surface of the molecule" are defined with reference
to Example 1, where the calculations, etc. are described in
detail.
[0083] It should be noted that when the terms "at least 25% of its
side chain exposed to the surface of the molecule" and "at least
50% of its side chain exposed to the surface of the molecule" are
used in connection with introduction of an in vivo N-glycosylation
site these terms refer to the surface accessibility of the amino
acid side chain in the position where the sugar moiety is actually
attached. In many cases it will be necessary to introduce a serine
or a threonine residue in position +2 relative to the asparagine
residue to which the sugar moiety is actually attached (unless, of
course, this position is already occupied by a serine or a
threonine residue) and these positions, where the serine or
threonine residues are introduced, are allowed to be buried, i.e.
to have less than 25% or 50% of their side chains exposed to the
surface of the molecule.
[0084] The terms "tissue factor binding site", "active site region"
and "ridge of the active site binding cleft" are defined with
reference to Example 1 herein, wherein the above-mentioned
sites/regions are determined.
[0085] The term "hydrophobic amino acid residue" includes the
following amino acid residues: isoleucine (I), leucine (L),
methionine (M), valine (V), phenylalanine (F), tyrosine (Y) and
tryptophan (W).
[0086] The term "negatively charged amino acid residue" includes
the following amino acid residues: Aspartic acid (D) and glutamic
acid (E).
[0087] The term "positively charged amino acid residue" includes
the following amino acid residues: Lysine (K), arginine (R) and
histidine (H).
Variants of the Invention
[0088] In its broadest aspect the present invention relates to a
FVII or FVIIa polypeptide variant having an amino acid sequence
comprising 3-15 amino acid modifications relative to hFVII or
hFVIIa having the amino acid sequence shown in SEQ ID NO:2, wherein
said amino acid sequence of the variant comprises an amino acid
substitution in position 10 and 32 and wherein a sugar moiety is
covalently attached to an introduced in vivo N-glycosylation site
located outside the Gla domain.
[0089] The modifications perfomed in the two above-indicated
regions of the parent FVII polypeptide serve the following
purposes:
[0090] The modifications performed in positions located outside the
Gla domain (introduction of in vivo N-glycosylation site(s)) are
preferably of such nature that the AUC.sub.iv, the functional in
vivo half-life and/or the serum half-life of the resulting variant
is increased as compared to rhFVIIa.
[0091] The modifications perfomed in the Gla domain of the parent
polypeptide are preferably of such nature that an increased
phospholipid membrane binding affinity of the resulting molecule is
achieved and/or of such nature the resulting molecule has an
improved capability to activate FX to FXa and/or of such nature
that a stronger clot is formed.
[0092] Without being limited by any particular theory, it is
presently believed that the enhanced membrane affinity results in a
higher local concentration of the activated polypeptide variants in
close proximity to the other coagulation factors, particularly FX.
Thus, the rate of activation of FX to FXa will be higher, simply
due to a higher molar ratio of the activated FVII variant to FX.
The increased activation rate of FX then results in a higher amount
of active thrombin, and thus a higher rate of cross-linking of
fibrin.
[0093] Thus, in preferred embodiments of the invention the parent
FVII or FVIIa polypeptide has been modified so that the resulting
activated polypeptide variant has (as compared to rhFVIIa): [0094]
i) an increased bioavailability (AUC.sub.iv) and an increased
phospholipid membrane binding affinity; [0095] ii) an increased
bioavailability (AUC.sub.iv) and an increased capability to
activate FX to FXa; [0096] iii) an increased bioavailability
(AUC.sub.iv) and is capable of generating a stronger clot
(increased AUC.sub.throm); [0097] iv) an increased bioavailability
(AUC.sub.iv) and a reduced T.sub.max; [0098] v) an increased
functional in vivo half-life and an increased phospholipid membrane
binding affinity; [0099] vi) an increased functional in vivo
half-life and an increased capability to activate FX to FXa; [0100]
vii) an increased functional in vivo half-life and is capable of
generating a stronger clot (increased AUC.sub.throm); [0101] viii)
an increased functional in vivo half-life and a reduced T.sub.max;
[0102] ix) an increased serum half-life and an increased
phospholipid membrane binding affinity; [0103] x) an increased
serun half-life and an increased capability to activate FX to FXa;
[0104] xi) an increased serum half-life and is capable of
generating a stronger clot (increased AUC.sub.throm); and/or [0105]
xii) an increased serum half-life and a reduced T.sub.max.
[0106] Consequently, medical treatment with a polypeptide variant
according to the invention offers a number of advantages over the
currently available rhFVIIa compound (NovoSeven.RTM.), such as
administration of lower dosage, longer duration between injections,
increased clot strength and/or faster action.
[0107] Thus, preferred variants of the invention are such variants
which, in their activated forms and when compared to rhFVIIa,
generates in increased Area Under the Curve when administered
intravenously (AUC.sub.iv), in particular when administered
intravenously in rats. More particularly, variants of the present
invention, which are preferred, are such variants where the ratio
between the AUC.sub.iv of said variant, in its actvated form, and
the AUC.sub.iv of rhFVIIa is at least 1.25, such as at least 1.5,
e.g. at least 1.75, more preferably at least 2, such as at least 3,
even more preferably at least 4, such as at least 5, in particular
when administered (intravenously) in rats.
[0108] This effect may in turn (but do not necessarily do so)
correspond to an increased functional in vivo half-life and/or an
increased serum half-life as compared to rhFVIIa. Accordingly, in
another preferred embodiment of the invention, the ratio between
the functional in vivo half-life or the serum half-life for the
variant, in its activated form, and the functional in vivo
half-life or the serum half-life for rhFVIIa is at least 1.25. More
preferably, the ratio between the relevant half-life for the
variant, in its activated form, and the relevant half-life for
hFVIIa or rhFVIIa is at least 1.5, such as at least 1.75, e.g. at
least 2, even more preferably at least 3, such as at least 4, e.g.
at least 5.
[0109] As will be understood, the variants of the invention also
possess, in addition to the above-mentioned functionality (i.e.
increased AUC.sub.iv, increased functional in vivo half-life and/or
increased serum half-life), an increased phospholipid membrane
binding affinity as compared to rhFVII, an an increased capability
to activate FX to Fxa, a capability of generating a stronger clot
(increased AUC.sub.throm) and/or a reduced T.sub.max.
[0110] Thus, in one preferred embodiment of the invention, the
polypeptide variant has (in addition to an increased AUC.sub.iv,
increased functional in vivo half-life and/or increased serum
half-life) an increased phospholipid membrane binding affinity
relative to rhFVIIa. Membrane binding affinity may be measured by
methods known in the art, such as by the Biacore.RTM. assay
described in K. Nagata and H. Handa (Ads.), Real-Time Analysis of
Biomolecular Interactions, Springer-Verlag, Tokyo, 2000, Chapter 6
entitled "Lipid-Protein Interactions". Alternatively, the membrane
binding affinity may be measured as described in Example 1 in WO
99/20767.
[0111] In another preferred embodiment of the invention, the
polypeptide variant (in addition to an increased AUC.sub.iv,
increased functional in vivo half-life and/or increased serum
half-life), has an increased FX activation activity as compared to
rhFVIIa, in particular when assayed in a TF-independent assay, such
as the "TF-independent Factor X Activation Assay" disclosed herein.
More particularly, it is preferred that the ratio between the FX
activation activity of the polypeptide variant, in its activated
form, and the FX activation activity of rhFVIIa is at least 1.25
when assayed in the "TF-independent Factor X Activation Assay"
disclosed herein. More preferably, the ratio between the FX
activation activity of the variant, in its activated form, and the
FX activation activity of rhFVIIa is at least 1.5, such as at least
1.75, e.g. at least 2, even more preferably at least 3, such as at
least 4, e.g. at least 5, still more preferably at least 6, such as
at least 7, e.g. at least 8, most preferably at least 9, such as at
least 10, when assayed in the "TF-independent Factor X Activation
Assay" described herein.
[0112] In still another preferred embodiment of the invention, the
polypeptide variant is (in addition to an increased AUC.sub.iv,
increased functional in vivo half-life and/or increased serum
half-life), in its activated form, capable of generating a stronger
clot as compared to rhFVIIa. This effect may be determined in the
"Thrombogram Assay" described herein as an increase in the Area
Under the Curve (AUC.sub.throm). The AUC.sub.throm is also
sometimes denoted "total thrombin work" and constitutes a measure
for the strength of the clot formed. More particularly, it is
preferred that the ratio between the AUC.sub.throm, generated by
the variant in its activated form, and the AUC.sub.throm generated
by rhFVIIa is at least 1.15 when assayed in the "Thrombogram Assay"
described herein. More preferably, the ratio is at least 1.2, such
as at least 1.25, e.g. at least 1.3, even more preferably at least
1.4, such as at least 1.5, e.g. at least 1.6, most preferably at
least 1.7, such as at least 1.8, e.g. at least 1.9 or at least
2.
[0113] In even another preferred embodiment of the invention the
polypeptide variant has (in addition to an increased AUC.sub.iv,
increased functional in vivo half-life and/or increased serum
half-life), in its activated form, a faster action. This effect may
be determined in the "Thrombogram Assay" described herein as a
reduction in the time needed to reach maximum thrombin level
(T.sub.max). Accordingly, preferred variants are such variants
where the ratio between T.sub.max for the variant, in its activated
form, and T.sub.max for rhFVIIa is at the most 0.95 when assayed in
the "Thrombogram Assay" described herein. Preferably, the ratio is
at the most 0.9, such as at the most 0.8, e.g. at the most 0.7,
more preferably at the most 0.6, such as at the most 0.5.
Introduction of In Vivo N-glycosylation Sites Located Outside the
Gla Domain
[0114] A number of suitable modifications leading to an increase in
AUC.sub.iv, functional in vivo half-life and/or serum half-life is
disclosed in WO 01/58935. The variants disclosed in WO 01/58935 are
the result of a generally new strategy for developing improved FVII
or FVIIa molecules, which may also be used for the parent FVII or
FVIIa polypeptide of the present invention.
[0115] The position to be modified is preferably selected from a
part of the FVII or FVIIa molecule that is located outside the
tissue factor binding site, and/or outside the active site region,
and/or outside the ridge of the active site binding cleft. These
sites/regions are identified in Example 1 herein. It should be
emphasized, however, that in certain situations, e.g. in case an
inactivated polypeptide variant is desired, it may be advantageous
to perform modifications in or close to such regions. For example,
it is contemplated that one or more in vivo N-glycosylation sites
may advantageously be introduced in the active site region or at
the ridge of the active site binding cleft of the FVII or FVIIa
molecule. The active site region, the tissue factor binding site
and the ridge of the active site binding cleft are defined in
Example 1 herein and are constituted by the following residues:
[0116] I153, Q167, V168, L169, L170, L171, Q176, L177, C178, G179,
G180, T181, V188, V189, S190, A191, A192, H193, C194, F195, D196,
K197, I198, W201, V228, I229, I230, P231, S232, T233, Y234, V235,
P236, G237, T238, T239, N240, H241, D242, I243, A244, L245, L246,
V281, S282, G283, W284, G285, Q286, T293, T324, E325, Y326, M327,
F328, D338, S339, C340, K341, G342, D343, S344, G345, G346, P347,
H348, L358, T359, G360, 1361, V362, S363, W364, G365, C368, V376,
Y377, T378, R379, V380, Q382, Y383, W386, L387, L400 and F405
(active site region);
[0117] L13, K18, F31, E35, R36, L39, F40, I42, S43, S60, K62, D63,
Q64, L65, I69, C70, F71, C72, L73, P74, F76, E77, G78, R79, E82,
K85, Q88, I90, V92, N93, E94, R271, A274, F275, V276, R277, F278,
R304, L305, M306, T307, Q308, D309, Q312, Q313, E325 and R379
(tissue factor binding site); and
[0118] N173, A175, K199, N200, N203, D289, R290, G291, A292, P321
and T370 (the ridge of the active site binding cleft).
[0119] The total number of amino acid residues to be modified
outside the Gla domain in the parent FVII or FVIIa polypeptide (as
compared to the amino acid sequence shown in SEQ ID NO:2) will
typically not exceed 10. Preferably, the FVII or FVIIa variant
comprises an amino acid sequence which differs in 1-10 amino acid
residues from amino acid residues 46-406 shown in SEQ ID NO:2,
typically in 1-8 or in 2-8 amino acid residues, e.g. in 1-5 or in
2-5 amino acid residues, such as in 1-4 or in 1-3 amino acid
residues, e.g. in 1, 2 or 3 amino acid residues from amino acid
residues 46-406 shown in SEQ ID NO:2.
[0120] Thus, the polypeptide variant of the invention may contain
1-10 (additional or introduced) in vivo N-glycosylation sites,
typically 1-8 or 2-8 (additional or introduced) in vivo
N-glycosylation sites, preferably 1-5 or 2-5 (additional or
introduced) in vivo N-glycosylation sites, such as 1-4 or 1-3
(additional or introduced) in vivo N-glycosylation sites, e.g. 1, 2
or 3 (additional or introduced) in vivo N-glycosylation sites.
Analogously, the polypeptide variant of the invention may contain
1-10 (additional or introduced) sugar moieties, typically 1-8 or
2-8 (additional or introduced) sugar moieties, preferably 1-5 or
2-5 (additional or introduced) sugar moieties, such as 1-4 or 1-3
(additional or introduced) sugar moieties, e.g. 1, 2 or 3
(additional or introduced) sugar moieites. It will be understood
that the introduced sugar moiety/moieties will be covalently
attached to the introduced in vivo N-glycosylation site(s)
[0121] When used in the present context, the term "naturally
occurring glycosylation site" covers the glycosylation sites at
postions N145, N322, S52 and S60. In a similar way, the term
"naturally occurring in vivo O-glycosylation site" includes the
positions S52 and S60, whereas the term "naturally occurring in
vivo N-glycosylation site" includes positions N145 and N322.
[0122] It will be understood that in order to prepare a polypeptide
variant, wherein the polypeptide variant comprises one or more
sugar moieties covalently attached to one or more in vivo
N-glycosylation sites, the polypeptide variant must be expressed in
a host cell capable of attaching sugar (oligosaccharide) moieties
at the glycosylation site(s) or alternatively subjected to in vitro
glycosylation. Examples of glycosylating host cells are given in
the section further below entitled "Coupling to a sugar
moiety".
[0123] Examples of positions, wherein the in vivo N-glycosylation
sites may be introduced include, but is not limited to, positions
comprising an amino acid residue having an amino acid residue
having at least 25% of its side chain exposed to the surface (as
defined in Example 1 herein), such as in a position comprising an
amino acid residue having at least 50% of its side chain exposed to
the surface (as defined in Example 1 herein). In general, it is
preferred that the in vivo N-glycosylation site is introduced by
substitution, although insertion is also contemplated. The position
is preferably selected from a part of the molecule that is located
outside the tissue factor binding site and/or the active site
region and/or outside the ridge of the active site cleft. These
sites/regions are identified in Example 1 herein. It should be
understood that when the term "at least 25% (or at least 50%) of
its side chain exposed to the surface" is used in connection with
introduction of an in vivo N-glycosylation site this term refers to
the surface accessibility of the amino acid side chain in the
position where the sugar moiety is actually attached. In many cases
it will be necessary to introduce a serine or a threonine residue
in position +2 relative to the asparagine residue to which the
sugar moiety is actually attached (unless, of course, this position
is already occupied by a serine or a threonine residue) and these
positions, where the serine or threonine residues are introduced,
are allowed to be buried, i.e. to have less than 25% of their side
chains exposed to the surface.
[0124] Specific and preferred examples of such substitutions
creating an in vivo N-glycosylation site include a substitution
selected from the group consisting of A51N, G58N, T106N, K109N,
G124N, K143N+N145T, A175T, I205S, I205T, V253N, T267N, T267N+S269T,
S314N+K316S, S314N+K316T, R315N+V317S, R315N+V317T, K316N+G318S,
K316N+G318T, G318N, D334N and combinations thereof. More
preferably, the in vivo N-glycosylation site is introduced by a
substitution selected from the group consisting of A51N, G58N,
T106N, K109N, G124N, K143N+N145T, A175T, I205T, V253N, T267N+S269T,
S314N+K316T, R315N+V317T, K316N+G318T, G318N, D334N and
combinations thereof. Even more preferably, the in vivo
N-glycosylation site is introduced by a substitution selected from
the group consisting of T106N, A175T, I205T, V253N, T267N+S269T and
combinations thereof, in particular I205T.
[0125] In one embodiment, only one in vivo N-glycosylation site has
been introduced by substitution. In another embodiment, two or more
(such as two) in vivo N-glycosylation sites have been introduced by
substitution. Examples of preferred substitutions creating two in
vivo N-glycosylation sites include substitutions selected from the
group consisting of A51N+G58N, A51N+T106N, A51N+K109N, A51N+G124N,
A51N+K143N+N145T, A51N+A175T, A51N+I205T, A51N+V253N,
A51N+T267N+S269T, A51N+S314N+K316T, A51N+R315N+V317T,
A51N+K316N+G318T, A51N+G318N, A51N+D334N, G58N+T106N, G58N+K109N,
G58N+G124N, G58N+K143N+N145T, G58N+A175T, G58N+I205T, G58N+V253N,
G58N+T267N+S269T, G58N+S314N+K316T, G58N+R315N+V317T,
G58N+K316N+G318T, G58N+G318N, G58N+D334N, T106N+K109N, T106N+G124N,
T106N+K143N+N145T, T106N+A175T, T106N+I205T, T106N+V253N,
T106N+T267N+S269T, T106N+S314N+K316T, T106N+R315N+V317T,
T106N+K316N+G318T, T106N+G318N, T106N+D334N, K109N+G124N,
K109N+K143N+N145T, K109N+A175T, K109N+I205T, K109N+V253N,
K109N+T267N+S269T, K109N+S314N+K316T, K109N+R315N+V317T,
K109N+K316N+G318T, K109N+G318N, K109N+D334N, G124N+K143N+N145T,
G124N+A175T, G124N+I205T, G124N+V253N, G124N+T267N+S269T,
G124N+S314N+K316T, G124N+R315N+V317T, G124N+K316N+G318T,
G124N+G318N, G124N+D334N, K143N+N145T+A175T, K143N+N145T+I205T,
K143N+N145T+V253N, K143N+N145T+T267N+S269T,
K143N+N145T+S314N+K316T, K143N+N145T+R315N+V317T,
K143N+N145T+K316N+G318T, K143N+N145T+G318N, K143N+N145T+D334N,
A175T+I205T, A175T+V253N, A175T+T267N+S269T, A175T+S314N+K316T,
A175T+R315N+V317T, A175T+K316N+G318T, A175T+G318N, A175T+D334N,
I205T+V253N, I205T+T267N+S269T, I205T+S314N+K316T,
I205T+R315N+V317T, I205T+K316N+G318T, I205T+G318N, I205T+D334N,
V253N+T267N+S269T, V253N+S314N+K316T, V253N+R315N+V317T,
V253N+K316N+G318T, V253N+G318N, V253N+D334N,
T267N+S269T+S314N+K316T, T267N+S269T+R315N+V317T,
T267N+S269T+K316N+G318T, T267N+S269T+G318N, T267N+S269T+D334N,
S314N+K316T+R315N+V317T, S314N+K316T+G318N, S314N+K316T+D334N,
R315N+V317T+K316N+G318T, R315N+V317T+G318N, R315N+V317T+D334N and
G318N+D334N. More preferably, the substitutions are selected from
the group consisiting of T106N+A175T, T106N+I205T, T106N+V253N,
T106N+T267N+S269T, A175T+I205T, A175T+V253N, A175T+T267N+S269T,
I205T+V253N, I205T+T267N+S269T and V253N+T267N+S269T, even more
preferably from the group consisiting of T106N+I205T, T106N+V253N
and I205T+T267N+S269T.
[0126] In an even further embodiment, three or more (such as three)
in vivo N-glycosylation sites have been introduced by substitution.
Examples of preferred substitutions creating three in vivo
N-glycosylation sites include substitutions selected from the group
consisiting of I205T+V253N+T267N+S269T and T106N+I205T+V253N.
[0127] As discussed above, it is preferred that the in vivo
N-glycosylation site is introduced in a position which does neither
form part of the tissue factor binding site nor form part of the
active site region and the ridge of the active site binding cleft
as defined herein. It is envisaged that such glycosylation variants
will primarily belong to the class of active polypeptide variants
as defined hereinbefore.
[0128] It will be understood that as an alternative to introduction
of in vivo N-glycosylation sites in the above-discussed positions
one may introduce (either by substitution or by insertion) cysteine
residues in the same positions, where the introduced cysteine
residue is then subsequently covalently attached to a
non-polypeptide moiety, such as PEG, in particular mPEG. Thus,
examples of positions, wherein a cysteine residue may be introduced
include, but is not limited to, positions comprising an amino acid
residue having an amino acid residue having at least 25% of its
side chain exposed to the surface (as defined in Example 1 herein),
such as in a position comprising an amino acid residue having at
least 50% of its side chain exposed to the surface (as defined in
Example 1 herein). The position is preferably selected from a part
of the molecule that is located outside the tissue factor binding
site and/or the active site region and/or outside the ridge of the
active site cleft. These sites/regions are identified in Example 1
herein. Thus, the above disclosure concerning introduction of in
vivo N-glycosylation sites applies mutatis mutandis to introduction
of cysteine residues.
[0129] It will be understood that the modifications in positions
located outside the Gla domain discussed in the above section
should be combined with one or more modifications in the Gla domain
(see the section entitled "Modifications in the Gla domain"
below).
Modifications in the Gla Domain
[0130] As will be understood the variants of the present invention
comprises, in addition to at least one introduced in vivo
N-glycosylation site located outside the Gla domain (cf. above), at
least two substitutions in the Gla domain, namely a substitution in
position 10 and position 32.
[0131] A number of suitable modifications leading to increased
phospholipid membrane binding affinity is disclosed in WO 99/20767
and WO 00/66753.
[0132] In a preferred embodiment of the invention the substitution
in position 10 is P10Q. In another preferred embodiment of the
invention the substitution in position 32 is K32E. In a
particularly preferred embodiment of the invention the variant
comprises the following substitutions P10Q+K32E.
[0133] In an interesting embodiment of the invention the variant
comprises, in addition to the substitutions in position 10 and 32,
such as in addition to the substitutions P10Q+K32E, at least one
further modification in the Gla domain.
[0134] In one preferred embodiment of the invention the further
modification in the Gla domain comprises an amino acid substitution
in position 33. Preferably, a hydrophobic amino acid residue is
introduced by substitution in position 33, such as D33I, D33L,
D33M, D33V, D33F, D33Y or D33W, in particular D33F. Accordingly, in
one very interesting embodiment of the invention, the variant
comprises the following substitutions P10Q+K32+D33F.
[0135] In another preferred embodiment of the invention the further
modification in the Gla domain comprises an insertion of at least
one (such as one) amino acid residue between position 3 and 4. It
is preferred that the inserted amino acid residue is a hydrophobic
amino acid residue. Most preferably the insertion is A3AY.
Accordingly, in another very interesting embodiment of the
invention, the variant comprises the following modifications
A3AY+P10Q+K32E or A3AY+P10Q+K32E+D33F.
[0136] In still another preferred embodiment of the invention the
further modification in the Gla domain comprises a substitution in
position 34. It is preferred that a negatively charged amino acid
residue is introduced by substitution in position 34. Most
preferably the substitution is A34E. Accordingly, in still another
very interesting embodiment of the invention, the variant comprises
the following modifications P10Q+K32E+A34E, P10Q+K32E+D33F+A34E,
A3AY+P10Q+K32E+A34E or A3AY+P10Q+K32E+D33F+A34E.
[0137] The Gla domain may also contain modifications in other
positions, in particular in positions 8, 11 and 28, such as R28F or
R28E. On the other hand it should be understood that the Gla domain
should not be modified to such an extent that the membrane binding
properties are impaired. Accordingly, it is preferred that no
modifications are made in the residues that become 7-carboxylated,
i.e. it is preferred that no modifications are made in residues 6,
7, 14, 16, 19, 20, 25, 26, 29 and 35. In a similar way, it is in
general not preferred that non-polypeptide moieties, such as sugar
moieties and/or PEG groups, are introduced in the Gla domain.
Consequently, it is preferred that no modifications are made in the
Gla domain that creates an in vivo N-glycosylation site.
[0138] Finally, it will be understood that the modifications in the
Gla domain discussed in this section must be combined with one or
more of the modifications disclosed in the section entitled
"Introduction of in vivo N-glycosylation sites located outside the
Gla domain" above.
[0139] Specific examples of such "combined" variants are given
below.
[0140] In one embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+T106N.
[0141] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+A175T.
[0142] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+I205T.
[0143] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+V253N.
[0144] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+T267+S269T.
[0145] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+T106N+I205T.
[0146] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+T106N+V253N.
[0147] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+I205T+T267N+S269T. In a further embodiment of the
invention said FVII or FVIIa variant comprises the following
modifications: A3AY+P10Q+K32E+T106N.
[0148] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+A175T.
[0149] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+I205T.
[0150] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+V253N.
[0151] In a further preferred embodiment of the invention said FVII
or FVIIa variant comprises the following modifications:
A3AY+P10Q+K32E+T267+S269T.
[0152] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+T106N+I205T.
[0153] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+T106N+V253N.
[0154] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+I205T+T267N+S269T.
[0155] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+T106N.
[0156] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+A175T.
[0157] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+I205T.
[0158] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+V253N.
[0159] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+T267+S269T.
[0160] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+T106N+I205T.
[0161] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+T106N+V253N.
[0162] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+I205T+T267N+S269T.
[0163] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+T106N.
[0164] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A175T.
[0165] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+T205T.
[0166] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+V253N.
[0167] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+T267+S269T.
[0168] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+T106N+I205T.
[0169] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+T106N+V253N.
[0170] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+I205T+T267N+S269T.
[0171] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+A34E+T106N.
[0172] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+A34E+A175T.
[0173] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+A34E+I205T.
[0174] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+A34E+V253N.
[0175] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+A34E+T267+S269T.
[0176] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+A34E+T106N+I205T.
[0177] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+A34E+T106N+V253N.
[0178] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+A34E+I205T+T267N+S269T.
[0179] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
P10Q+K32E+D33F+A34E+T106N.
[0180] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+D33F+A34E
A175T.
[0181] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+D33F+A34E
I205T.
[0182] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+D33F+A34E
V253N.
[0183] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+D33F+A34E
T267+S269T.
[0184] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+D33F+A34E
T106N+I205T.
[0185] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+D33F+A34E
T106N+V253N.
[0186] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: P10Q+K32E+D33F+A34E
I205T+T267N+S269T.
[0187] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+A34E+T106N.
[0188] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: A3AY+P10Q+K32E+A34E
A175T.
[0189] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: A3AY+P10Q+K32E+A34E
I205T.
[0190] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: A3AY+P10Q+K32E+A34E
V253N.
[0191] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: A3AY+P10Q+K32E+A34E
T267+S269T.
[0192] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: A3AY+P10Q+K32E+A34E
T106N+I205T.
[0193] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: A3AY+P10Q+K32E+A34E
T106N+V253N.
[0194] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications: A3AY+P10Q+K32E+A34E
I205T+T267N+S269T.
[0195] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A34E+T106N.
[0196] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A34E A175T.
[0197] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A34E I205T.
[0198] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A34E V253N.
[0199] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A34E T267+S269T.
[0200] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A34E T106N+I205T.
[0201] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A34E T106N+V253N.
[0202] In a further embodiment of the invention said FVII or FVIIa
variant comprises the following modifications:
A3AY+P10Q+K32E+D33F+A34E I205T+T267N+S269T.
Other Modifications Outside the Gla Domain
[0203] In a further embodiment of the present invention, the FVII
or FVIIa variant may, in addition to the modifications described in
the sections above, also contain mutations, which are already known
to increase the intrinsic activity of the polypeptide, e.g. such as
those described in WO 02/22776
[0204] Examples of preferred substitutions include substitutions
selected from the group consisting of V158D, E296D, M298Q, L305V
and K337A. More preferably, said substitutions are selected from
the group consisting of V158D+E296D+M298Q+L305V+K337A,
V158D+E296D+M298Q+K337A, V158D+E296D+M298Q+L305V,
V158D+E296D+M298Q, M298Q, L305V+K337A, L305V and K337A.
[0205] In a further embodiment of the present invention, the FVII
or FVIIa variant may, in addition to the modifications described in
the sections above, also contain mutations, which are already known
to cause a decreased inhibition by TFPI. One example includes the
substitution K341Q disclosed by Neuenschwander et al, Biochemistry,
1995; 34:8701-8707.
[0206] Moreover, the variant may contain modifications which are
belived to increase the TF binding affinity. Examples of such
modifications include substitutions selected from the group
consisting of L39E, L39Q, L39H, I42K, I42R, S43H, S43Q, K62E, K62R,
L65Q, L65S, F71D, F71Y, F71E, F71Q, F71N, E82Q, E82N, E82K and
F275H
[0207] As already indicated above, the variant may also contain
conservative amino acid substitutions.
The Non-Polypeptide Moiety
[0208] Based on the present disclosure the skilled person will be
aware that amino acid residues comprising other attachment groups
may be introduced by substitution into the parent polypeptide,
using the same approach as that illustrated above with in vivo
N-glycosylation sites. For instance, one or more amino acid
residues comprising an acid group (glutamic acid or aspartic acid),
tyrosine or lysine may be introduced into the positions discussed
above. In particular, one or more cysteine residues may be
introduced in the positions discussed above.
[0209] As indicated further above the non-polypeptide moiety of the
conjugated variant is preferably selected from the group consisting
of a polymer molecule, a lipophilic compound, a sugar moiety (by
way of in vivo glycosylation) and an organic derivatizing agent.
All of these agents may confer desirable properties to the variant
polypeptide, in particular increased AUC.sub.iv, increased
functional in vivo half-life and/or increased plasma half-life. The
variant polypeptide is normally conjugated to only one type of
non-polypeptide moiety, but may also be conjugated to two or more
different types of non-polypeptide moieties, e.g. to a polymer
molecule and a sugar moiety, to a lipophilic group and a sugar
moiety, to an organic derivatizing agent and a sugar moiety, to a
lipophilic group and a polymer molecule, etc. The conjugation to
two or more different non-polypeptide moieties may be done
simultaneous or sequentially.
Methods of Preparing a Conjugated Variant of the Invention
[0210] In the following sections "Conjugation to a lipophilic
compound", "Conjugation to a polymer molecule", "Conjugation to a
sugar moiety" and "Conjugation to an organic derivatizing agent"
conjugation to specific types of non-polypeptide moieties is
described. In general, a conjugated variant according to the
invention may be produced by culturing an appropriate host cell
under conditions conducive for the expression of the variant
polypeptide, and recovering the variant polypeptide, wherein a) the
variant polypeptide comprises at least one N- or O-glycosylation
site and the host cell is an eukaryotic host cell capable of in
vivo glycosylation, and/or b) the variant polypeptide is subjected
to conjugation to a non-polypeptide moiety in vitro.
[0211] It will be understood that the conjugation should be
designed so as to produce the optimal molecule with respect to the
number of non-polypeptide moieties attached, the size and form of
such molecules (e.g. whether they are linear or branched), and the
attachment site(s) in the polypeptide. The molecular weight of the
non-polypeptide moiety to be used may, e.g., be chosen on the basis
of the desired effect to be achieved. For instance, if the primary
purpose of the conjugation is to achieve a conjugated variant
having a high molecular weight (e.g. to reduce renal clearance) it
is usually desirable to conjugate as few high molecular weight
non-polypeptide moieties as possible to obtain the desired
molecular weight. When a high degree of shielding is desirable this
may be obtained by use of a sufficiently high number of low
molecular weight non-polypeptide moieties (e.g. with a molecular
weight of from about 300 Da to about 5 kDa, such as a molecular
weight of from 300 Da to 2 kDa).
Conjugation to a Polymer Molecule
[0212] The polymer molecule to be coupled to the variant
polypeptide may be any suitable polymer molecule, such as a natural
or synthetic homo-polymer or hetero-polymer, typically with a
molecular weight in the range of about 300-100,000 Da, such as
about 500-20,000 Da, more preferably in the range of about
500-15,000 Da, even more preferably in the range of about 2-12 kDa,
such as in the range of about 3-10 kDa. When the term "about" is
used herein in connection with a certain molecular weight, the word
"about" indicates an approximate average molecular weight and
reflects the fact that there will normally be a certain molecular
weight distribution in a given polymer preparation.
[0213] Examples of homo-polymers include a polyol (i.e. poly-OH), a
polyamine (i.e. poly-NH.sub.2) and a polycarboxylic acid (i.e.
poly-COOH). A hetero-polymer is a polymer comprising different
coupling groups, such as a hydroxyl group and an amine group.
[0214] Examples of suitable polymer molecules include polymer
molecules selected from the group consisting of polyalkylene oxide
(PAO), including polyalkylene glycol (PAG), such as polyethylene
glycol (PEG) and polypropylene glycol (PPG), branched PEGs,
poly-vinyl alcohol (PVA), poly-carboxylate, poly-(vinylpyrolidone),
polyethylene-co-maleic acid anhydride, polystyrene-co-maleic acid
anhydride, dextran, including carboxymethyl-dextran, or any other
biopolymer suitable for reducing immunogenicity and/or increasing
functional in vivo half-life and/or serum half-life. Another
example of a polymer molecule is human albumin or another abundant
plasma protein. Generally, polyalkylene glycol-derived polymers are
biocompatible, non-toxic, non-antigenic, non-immunogenic, have
various water solubility properties, and are easily excreted from
living organisms.
[0215] PEG is the preferred polymer molecule, since it has only few
reactive groups capable of cross-linking compared to, e.g.,
polysaccharides such as dextran. In particular, mono-functional
PEG, e.g. methoxypolyethylene glycol (mPEG), is of interest since
its coupling chemistry is relatively simple (only one reactive
group is available for conjugating with attachment groups on the
polypeptide). Consequently, as the risk of cross-linking is
eliminated, the resulting conjugated variants are more homogeneous
and the reaction of the polymer molecules with the variant
polypeptide is easier to control.
[0216] To effect covalent attachment of the polymer molecule(s) to
the variant polypeptide, the hydroxyl end groups of the polymer
molecule must be provided in activated form, i.e. with reactive
functional groups (examples of which include primary amino groups,
hydrazide (HZ), thiol, succinate (SUC), succinimidyl succinate
(SS), succinimidyl succinamide (SSA), succinimidyl propionate
(SPA), succinimidyl butyrate (SBA), succinimidy carboxymethylate
(SCM), benzotriazole carbonate (BTC), N-hydroxysuccinimide (NHS),
aldehyde, nitrophenylcarbonate (NPC), and tresylate (TRES)).
Suitable activated polymer molecules are commercially available,
e.g. from Shearwater Polymers, Inc., Huntsville, Ala., USA, or from
PolyMASC Pharmaceuticals plc, UK.
[0217] Alternatively, the polymer molecules can be activated by
conventional methods known in the art, e.g. as disclosed in WO
90/13540. Specific examples of activated linear or branched polymer
molecules for use in the present invention are described in the
Shearwater Polymers, Inc. 1997 and 2000 Catalogs (Functionalized
Biocompatible Polymers for Research and pharmaceuticals,
Polyethylene Glycol and Derivatives, incorporated herein by
reference).
[0218] Specific examples of activated PEG polymers include the
following linear PEGs: NHS-PEG (e.g. SPA-PEG, SSPA-PEG, SBA-PEG,
SS-PEG, SSA-PEG, SC-PEG, SG-PEG, and SCM-PEG), and NOR-PEG,
BTC-PEG, EPOX-PEG, NCO-PEG, NPC-PEG, CDI-PEG, ALD-PEG, TRES-PEG,
VS-PEG, IODO-PEG, and MAL-PEG, and branched PEGs such as PEG2-NHS
and those disclosed in U.S. Pat. No. 5,932,462 and U.S. Pat. No.
5,643,575, both of which are incorporated herein by reference.
Furthermore, the following publications, incorporated herein by
reference, disclose useful polymer molecules and/or PEGylation
chemistries: U.S. Pat. No. 5,824,778, U.S. Pat. No. 5,476,653, WO
97/32607, EP 229,108, EP 402,378, U.S. Pat. No. 4,902,502, U.S.
Pat. No. 5,281,698, U.S. Pat. No. 5,122,614, U.S. Pat. No.
5,219,564, WO 92/16555, WO 94/04193, WO 94/14758, WO 94/17039, WO
94/18247, WO 94/28024, WO 95/00162, WO 95/11924, WO95/13090, WO
95/33490, WO 96/00080, WO 97/18832, WO 98/41562, WO 98/48837, WO
99/32134, WO 99/32139, WO 99/32140, WO 96/40791, WO 98/32466, WO
95/06058, EP 439 508, WO 97/03106, WO 96/21469, WO 95/13312, EP 921
131, U.S. Pat. No. 5,736,625, WO 98/05363, EP 809 996, U.S. Pat.
No. 5,629,384, WO 96/41813, WO 96/07670, U.S. Pat. No. 5,473,034,
U.S. Pat. No. 5,516,673, EP 605 963, U.S. Pat. No. 5,382,657, EP
510 356, EP 400 472, EP 183 503 and EP 154 316.
[0219] Specific examples of activated PEG polymers particularly
preferred for coupling to cysteine residues, include the following
linear PEGs: vinylsulfone-PEG (VS-PEG), preferably
vinylsulfone-mPEG (VS-mPEG); maleimide-PEG (MAL-PEG), preferably
maleimide-mPEG (MAL-mPEG) and orthopyridyl-disulfide-PEG
(OPSS-PEG), preferably orthopyridyl-disulfide-mPEG (OPSS-mPEG).
Typically, such PEG or mPEG polymers will have a size of about 5
kDa, about 10 kD, about 12 kDa or about 20 kDa.
[0220] The conjugation of the polypeptide variant and the activated
polymer molecules is conducted by use of any conventional method,
e.g. as described in the following references (which also describe
suitable methods for activation of polymer molecules): Harris and
Zalipsky, eds., Poly(ethylene glycol) Chemistry and Biological
Applications, AZC, Washington; R. F. Taylor, (1991), "Protein
immobilisation. Fundamental and applications", Marcel Dekker, N.Y.;
S. S. Wong, (1992), "Chemistry of Protein Conjugation and
Crosslinking", CRC Press, Boca Raton; G. T. Hermanson et al.,
(1993), "Immobilized Affinity Ligand Techniques", Academic Press,
N.Y.).
[0221] The skilled person will be aware that the activation method
and/or conjugation chemistry to be used depends on the attachment
group(s) of the variant polypeptide (examples of which are given
further above), as well as the functional groups of the polymer
(e.g. being amine, hydroxyl, carboxyl, aldehyde, sulfydryl,
succinimidyl, maleimide, vinysulfone or haloacetate). The
PEGylation may be directed towards conjugation to all available
attachment groups on the variant polypeptide (i.e. such attachment
groups that are exposed at the surface of the polypeptide) or may
be directed towards one or more specific attachment groups, e.g.
the N-terminal amino group as described in U.S. Pat. No. 5,985,265
or to cysteine residues. Furthermore, the conjugation may be
achieved in one step or in a stepwise manner (e.g. as described in
WO 99/55377).
[0222] For PEGylation to cysteine residues (see above) the FVII or
FVIIa variant is usually treated with a reducing agent, such as
dithiothreitol (DDT) prior to PEGylation. The reducing agent is
subsequently removed by any conventional method, such as by
desalting. Conjugation of PEG to a cysteine residue typically takes
place in a suitable buffer at pH 6-9 at temperatures varying from
4.degree. C. to 25.degree. C. for periods up to 16 hours.
[0223] It will be understood that the PEGylation is designed so as
to produce the optimal molecule with respect to the number of PEG
molecules attached, the size and form of such molecules (e.g.
whether they are linear or branched), and the attachment site(s) in
the variant polypeptide. The molecular weight of the polymer to be
used may e.g. be chosen on the basis of the desired effect to be
achieved.
[0224] In connection with conjugation to only a single attachment
group on the protein (e.g. the N-terminal amino group), it may be
advantageous that the polymer molecule, which may be linear or
branched, has a high molecular weight, preferably about 10-25 kDa,
such as about 15-25 kDa, e.g. about 20 kDa.
[0225] Normally, the polymer conjugation is performed under
conditions aimed at reacting as many of the available polymer
attachment groups with polymer molecules. This is achieved by means
of a suitable molar excess of the polymer relative to the
polypeptide. Typically, the molar ratios of activated polymer
molecules to polypeptide are up to about 1000-1, such as up to
about 200-1, or up to about 100-1. In some cases the ration may be
somewhat lower, however, such as up to about 50-1, 10-1, 5-1, 2-1
or 1-1 in order to obtain optimal reaction.
[0226] It is also contemplated according to the invention to couple
the polymer molecules to the polypeptide through a linker. Suitable
linkers are well known to the skilled person. A preferred example
is cyanuric chloride (Abuchowski et al., (1977), J. Biol. Chem.,
252, 3578-3581; U.S. Pat. No. 4,179,337; Shafer et al., (1986), J.
Polym. Sci. Polym. Chem. Ed., 24, 375-378).
[0227] Subsequent to the conjugation, residual activated polymer
molecules are blocked according to methods known in the art, e.g.
by addition of primary amine to the reaction mixture, and the
resulting inactivated polymer molecules are removed by a suitable
method.
[0228] It will be understood that depending on the circumstances,
e.g. the amino acid sequence of the variant polypeptide, the nature
of the activated PEG compound being used and the specific
PEGylation conditions, including the molar ratio of PEG to
polypeptide, varying degrees of PEGylation may be obtained, with a
higher degree of PEGylation generally being obtained with a higher
ratio of PEG to variant polypeptide. The PEGylated variant
polypeptides resulting from any given PEGylation process will,
however, normally comprise a stochastic distribution of conjugated
polypeptide variants having slightly different degrees of
PEGylation.
Coupling to a Sugar Moiety
[0229] In order to achieve in vivo glycosylation of a FVII molecule
comprising one or more glycosylation sites the nucleotide sequence
encoding the variant polypeptide must be inserted in a
glycosylating, eucaryotic expression host. The expression host cell
may be selected from fungal (filamentous fungal or yeast), insect
or animal cells or from transgenic plant cells. In one embodiment
the host cell is a mammalian cell, such as a CHO cell, BHK or HEK,
e.g. HEK 293, cell, or an insect cell, such as an SF9 cell, or a
yeast cell, e.g. S. cerevisiae or Pichia pastoris, or any of the
host cells mentioned hereinafter.
[0230] Covalent in vitro coupling of sugar moieties (such as
dextran) to amino acid residues of the variant polypeptide may also
be used, e.g. as described, for example in WO 87/05330 and in Aplin
etl al., CRC Crit Rev. Biochem, pp. 259-306,1981. The in vitro
coupling of sugar moieties or PEG to protein- and peptide-bound
Gln-residues can be carried out by transglutaminases (TGases).
Transglutaminases catalyse the transfer of donor amine-groups to
protein- and peptide-bound Gln-residues in a so-called
cross-linking reaction. The donor-amine groups can be protein- or
peptide-bound, such as the s-amino-group in Lys-residues or it can
be part of a small or large organic molecule. An example of a small
organic molecule functioning as amino-donor in TGase-catalysed
cross-linking is putrescine (1,4-diaminobutane). An example of a
larger organic molecule functioning as amino-donor in
TGase-catalysed cross-linking is an amine-containing PEG (Sato et
al., 1996, Biochemistry 35, 13072-13080).
[0231] TGases, in general, are highly specific enzymes, and not
every Gln-residues exposed on the surface of a protein is
accessible to TGase-catalysed cross-linking to amino-containing
substances. On the contrary, only few Gln-residues are naturally
functioning as TGase substrates but the exact parameters governing
which Gln-residues are good TGase substrates remain unknown. Thus,
in order to render a protein susceptible to TGase-catalysed
cross-linking reactions it is often a prerequisite at convenient
positions to add stretches of amino acid sequence known to function
very well as TGase substrates. Several amino acid sequences are
known to be or to contain excellent natural TGase substrates e.g.
substance P, elafin, fibrinogen, fibronectin, .alpha..sub.2-plasmin
inhibitor, .alpha.-caseins, and .beta.-caseins.
Conjugation to an Organic Derivatizing Agent
[0232] Covalent modification of the variant polypeptide may be
performed by reacting one or more attachment groups of the variant
polypeptide with an organic derivatizing agent. Suitable
derivatizing agents and methods are well known in the art. For
example, cysteinyl residues most commonly are reacted with
.alpha.-haloacetates (and corresponding amines), such as
chloroacetic acid or chloroacetamide, to give carboxymethyl or
carboxyamidomethyl derivatives. Cysteinyl residues also are
derivatized by reaction with bromotrifluoroacetone,
.alpha.-bromo-.beta.-(4-imidozoyl)propionic acid, chloroacetyl
phosphate, N-alkylmaleimides, 3-nitro-2-pyridyl disulfide, methyl
2-pyridyl disulfide, p-chloromercuribenzoate,
2-chloromercuri-4-nitrophenol, or
chloro-7-nitrobenzo-2-oxa-1,3-diazole. Histidyl residues are
derivatized by reaction with diethylpyrocarbonateat pH 5.5-7.0
because this agent is relatively specific for the histidyl side
chain. Para-bromophenacyl bromide also is useful. The reaction is
preferably performed in 0.1 M sodium cacodylate at pH 6.0. Lysinyl
and amino terminal residues are reacted with succinic or other
carboxylic acid anhydrides. Derivatization with these agents has
the effect of reversing the charge of the lysinyl residues. Other
suitable reagents for derivatizing .alpha.-amino-containing
residues include imidoesters such as methyl picolinimidate,
pyridoxal phosphate, pyridoxal, chloroborohydride,
trinitrobenzenesulfonic acid, O-methylisourea, 2,4-pentanedione and
transaminase-catalyzed reaction with glyoxylate. Arginyl residues
are modified by reaction with one or several conventional reagents,
among them phenylglyoxal, 2,3-butanedione, 1,2cyclohexanedione, and
ninhydrin. Derivatization of arginine residues requires that the
reaction be performed in alkaline conditions because of the high
pKa of the guanidine functional group.
[0233] Furthermore, these reagents may react with the groups of
lysine as well as the arginine guanidino group. Carboxyl side
groups (aspartyl or glutamyl) are selectively modified by reaction
with carbodiimides (R--N.dbd.C.dbd.N--R'), where R and R' are
different alkyl groups, such as
1-cyclohexyl-3-(2-morpholinyl-4-ethyl)carbodiimide or
1-ethyl-3-(4-azonia-4,4-dimethylpentyl)carbodiimide. Furthermore,
aspartyl and glutamyl residues are converted to asparaginyl and
glutaminyl residues by reaction with ammonium ions.
Conjugation to a Lipophilic Compound
[0234] The variant polypeptide and the lipophilic compound may be
conjugated to each other, either directly or by use of a linker.
The lipophilic compound may be a natural compound such as a
saturated or unsaturated fatty acid, a fatty acid diketone, a
terpene, a prostaglandin, a vitamine, a carotenoide or steroide, or
a synthetic compound such as a carbon acid, an alcohol, an amine
and sulphonic acid with one or more alkyl-, aryl-, alkenyl- or
other multiple unsaturated compounds. The conjugation between the
variant polypeptide and the lipophilic compound, optionally through
a linker may be done according to methods known in the art, e.g. as
described by Bodanszky in Peptide Synthesis, John Wiley, New York,
1976 and in WO 96/12505.
Methods of Preparing a Polypeptide Variant of the Invention
[0235] The polypeptide variant of the present invention may be
produced by any suitable method known in the art. Such methods
include constructing a nucleotide sequence encoding the polypeptide
variant and expressing the sequence in a suitable transformed or
transfected host. Preferably, the host cell is a gammacarboxylating
host cell such as a mammalian cell. However, polypeptide variants
of the invention may be produced, albeit less efficiently, by
chemical synthesis or a combination of chemical synthesis or a
combination of chemical synthesis and recombinant DNA
technology.
[0236] A nucleotide sequence encoding a polypeptide of the
invention may be constructed by isolating or synthesizing a
nucleotide sequence encoding the parent FVII, such as hFVII with
the amino acid sequence shown in SEQ ID NO:2 and then changing the
nucleotide sequence so as to effect introduction (i.e. insertion or
substitution) or removal (i.e. deletion or substitution) of the
relevant amino acid residue(s).
[0237] The nucleotide sequence is conveniently modified by
site-directed mutagenesis in accordance with conventional methods.
Alternatively, the nucleotide sequence is prepared by chemical
synthesis, e.g. by using an oligonucleotide synthesizer, wherein
oligonucleotides are designed based on the amino acid sequence of
the desired polypeptide, and preferably selecting those codons that
are favored in the host cell in which the recombinant polypeptide
will be produced. For example, several small oligonucleotides
coding for portions of the desired polypeptide may be synthesized
and assembled by PCR, ligation or ligation chain reaction (LCR)
(Barany, PNAS 88:189-193, 1991). The individual oligonucleotides
typically contain 5' or 3' overhangs for complementary
assembly.
[0238] Alternative nucleotide sequence modification methods are
available for producing polypeptide variants for high throughput
screening, for instance methods which involve homologous cross-over
such as disclosed in U.S. Pat. No. 5,093,257, and methods which
involve gene shuffling, i.e. recombination between two or more
homologous nucleotide sequences resulting in new nucleotide
sequences having a number of nucleotide alterations when compared
to the starting nucleotide sequences. Gene shuffling (also known as
DNA shuffling) involves one or more cycles of random fragmentation
and reassembly of the nucleotide sequences, followed by screening
to select nucleotide sequences encoding polypeptides with desired
properties. In order for homology-based nucleic acid shuffling to
take place, the relevant parts of the nucleotide sequences are
preferably at least 50% identical, such as at least 60% identical,
more preferably at least 70% identical, such as at least 80%
identical. The recombination can be performed in vitro or in
vivo.
[0239] Examples of suitable in vitro gene shuffling methods are
disclosed by Stemmer et al. (1994), Proc. Natl. Acad. Sci. USA;
vol. 91, pp. 10747-10751; Stemmer (1994), Nature, vol. 370, pp.
389-391; Smith (1994), Nature vol. 370, pp. 32.sup.4-325; Zhao et
al., Nat. Biotechnol. 1998, Mar; 16(3): 258-61; Zhao H. and Arnold,
F B, Nucleic Acids Research, 1997, Vol. 25. No. 6 pp. 1307-1308;
Shao et al., Nucleic Acids Research 1998, Jan 15; 26(2): pp.
681-83; and WO 95/17413.
[0240] An example of a suitable in vivo shuffling method is
disclosed in WO 97/07205. Other techniques for mutagenesis of
nucleic acid sequences by in vitro or in vivo recombination are
disclosed e.g. in WO 97/20078 and U.S. Pat. No. 5,837,458. Examples
of specific shuffling techniques include "family shuffling",
"synthetic shuffling" and "in silico shuffling".
[0241] Family shuffling involves subjecting a family of homologous
genes from different species to one or more cycles of shuffling and
subsequent screening or selection. Family shuffling techniques are
disclosed e.g. by Crameri et al. (1998), Nature, vol. 391, pp.
288-291; Christians et al. (1999), Nature Biotechnology, vol. 17,
pp. 259-264; Chang et al. (1999), Nature Biotechnology, vol. 17,
pp. 793-797; and Ness et al. (1999), Nature Biotechnology, vol. 17,
893-896.
[0242] Synthetic shuffling involves providing libraries of
overlapping synthetic oligonucleotides based e.g. on a sequence
alignment of homologous genes of interest. The synthetically
generated oligonucleotides are recombined, and the resulting
recombinant nucleic acid sequences are screened and if desired used
for further shuffling cycles. Synthetic shuffling techniques are
disclosed in WO 00/42561.
[0243] In silico shuffling refers to a DNA shuffling procedure,
which is performed or modelled using a computer system, thereby
partly or entirely avoiding the need for physically manipulating
nucleic acids. Techniques for in silico shuffling are disclosed in
WO 00/42560.
[0244] Once assembled (by synthesis, site-directed mutagenesis or
another method), the nucleotide sequence encoding the polypeptide
is inserted into a recombinant vector and operably linked to
control sequences necessary for expression of the FVII in the
desired transformed host cell.
[0245] It should of course be understood that not all vectors and
expression control sequences function equally well to express the
nucleotide sequence encoding the polypeptide variants described
herein. Neither will all hosts function equally well with the same
expression system. However, one of skill in the art may make a
selection among these vectors, expression control sequences and
hosts without undue experimentation. For example, in selecting a
vector, the host must be considered because the vector must
replicate in it or be able to integrate into the chromosome. The
vector's copy number, the ability to control that copy number, and
the expression of any other proteins encoded by the vector, such as
antibiotic markers, should also be considered. In selecting an
expression control sequence, a variety of factors should also be
considered. These include, for example, the relative strength of
the sequence, its controllability, and its compatibility with the
nucleotide sequence encoding the polypeptide, particularly as
regards potential secondary structures. Hosts should be selected by
consideration of their compatibility with the chosen vector, the
toxicity of the product coded for by the nucleotide sequence, their
secretion characteristics, their ability to fold the polypeptide
variant correctly, their fermentation or culture requirements, and
the ease of purification of the products coded for by the
nucleotide sequence.
[0246] The recombinant vector may be an autonomously replicating
vector, i.e. a vector, which exists as an extrachromosomal entity,
the replication of which is independent of chromosomal replication,
e.g. a plasmid. Alternatively, the vector is one which, when
introduced into a host cell, is integrated into the host cell
genome and replicated together with the chromosome(s) into which it
has been integrated.
[0247] The vector is preferably an expression vector, in which the
nucleotide sequence encoding the polypeptide variant of the
invention is operably linked to additional segments required for
transcription of the nucleotide sequence. The vector is typically
derived from plasmid or viral DNA. A number of suitable expression
vectors for expression in the host cells mentioned herein are
commercially available or described in the literature. Useful
expression vectors for eukaryotic hosts, include, for example,
vectors comprising expression control sequences from SV40, bovine
papilloma virus, adenovirus and cytomegalovirus. Specific vectors
are, e.g., pCDNA3.1(+)\Hyg (Invitrogen, Carlsbad, Calif., USA) and
pCI-neo (Stratagene, La Jola, Calif., USA). Useful expression
vectors for yeast cells include the 2.mu. plasmid and derivatives
thereof, the POT1 vector (U.S. Pat. No. 4,931,373), the pJSO37
vector described in Okkels, Ann. New York Acad. Sci. 782, 202-207,
1996, and pPICZ A, B or C (Invitrogen). Useful vectors for insect
cells include pVL941, pBG311 (Cate et al., "Isolation of the Bovine
and Human Genes for Mullerian Inhibiting Substance And Expression
of the Human Gene In Animal Cells", Cell, 45, pp. 685-98 (1986),
pBluebac 4.5 and pMelbac (both available from Invitrogen). Useful
expression vectors for bacterial hosts include known bacterial
plasmids, such as plasmids from E. coli, including pBR322, pET3a
and pET12a (both from Novagen Inc., WI, USA), wider host range
plasmids, such as RP4, phage DNAs, e.g., the numerous derivatives
of phage lambda, e.g., NM989, and other DNA phages, such as M13 and
filamentous single stranded DNA phages.
[0248] Other vectors for use in this invention include those that
allow the nucleotide sequence encoding the polypeptide variant to
be amplified in copy number. Such amplifiable vectors are well
known in the art. They include, for example, vectors able to be
amplified by DHFR amplification (see, e.g., Kaufman, U.S. Pat. No.
4,470,461, Kaufman and Sharp, "Construction Of A Modular
Dihydrafolate Reductase cDNA Gene: Analysis Of Signals Utilized For
Efficient Expression", Mol. Cell. Biol., 2, pp. 1304-19 (1982)) and
glutamine synthetase ("GS") amplification (see, e.g., U.S. Pat. No.
5,122,464 and EP 338,841).
[0249] The recombinant vector may further comprise a DNA sequence
enabling the vector to replicate in the host cell in question. An
example of such a sequence (when the host cell is a mammalian cell)
is the SV40 origin of replication. When the host cell is a yeast
cell, suitable sequences enabling the vector to replicate are the
yeast plasmid 2.mu. replication genes REP 1-3 and origin of
replication.
[0250] The vector may also comprise a selectable marker, e.g. a
gene the product of which complements a defect in the host cell,
such as the gene coding for dihydrofolate reductase (DHFR) or the
Schizosaccharomyces pombe TPI gene (described by P. R. Russell,
Gene 40, 1985, pp. 125-130), or one which confers resistance to a
drug, e.g. ampicillin, kanamycin, tetracyclin, chloramphenicol,
neomycin, hygromycin or methotrexate. For Saccharomyces cerevisiae,
selectable markers include ura3 and leu2. For filamentous fungi,
selectable markers include amdS, pyrG, arcB, niaD and sC.
[0251] The term "control sequences" is defined herein to include
all components, which are necessary or advantageous for the
expression of the polypeptide variant of the invention. Each
control sequence may be native or foreign to the nucleic acid
sequence encoding the polypeptide variant. Such control sequences
include, but are not limited to, a leader sequence, polyadenylation
sequence, propeptide sequence, promoter, enhancer or upstream
activating sequence, signal peptide sequence, and transcription
terminator. At a minimum, the control sequences include a
promoter.
[0252] A wide variety of expression control sequences may be used
in the present invention. Such useful expression control sequences
include the expression control sequences associated with structural
genes of the foregoing expression vectors as well as any sequence
known to control the expression of genes of prokaryotic or
eukaryotic cells or their viruses, and various combinations
thereof.
[0253] Examples of suitable control sequences for directing
transcription in mammalian cells include the early and late
promoters of SV40 and adenovirus, e.g. the adenovirus 2 major late
promoter, the MT-1 (metallothionein gene) promoter, the human
cytomegalovirus immediate-early gene promoter (CMV), the human
elongation factor 1.alpha. (EF-1.alpha.) promoter, the Drosophila
minimal heat shock protein 70 promoter, the Rous Sarcoma Virus
(RSV) promoter, the human ubiquitin C (UbC) promoter, the human
growth hormone terminator, SV40 or adenovirus E1b region
polyadenylation signals and the Kozak consensus sequence (Kozak, M.
J Mol Biol 1987 Aug. 20; 196(4):947-50).
[0254] In order to improve expression in mammalian cells a
synthetic intron may be inserted in the 5' untranslated region of
the nucleotide sequence encoding the polypeptide. An example of a
synthetic intron is the synthetic intron from the plasmid pCI-Neo
(available from Promega Corporation, WI, USA).
[0255] Examples of suitable control sequences for directing
transcription in insect cells include the polyhedrin promoter, the
P10 promoter, the Autographa californica polyhedrosis virus basic
protein promoter, the baculovirus immediate early gene 1 promoter
and the baculovirus 39K delayed-early gene promoter, and the SV40
polyadenylation sequence. Examples of suitable control sequences
for use in yeast host cells include the promoters of the yeast
.alpha.-mating system, the yeast triose phosphate isomerase (TPI)
promoter, promoters from yeast glycolytic genes or alcohol
dehydrogenase genes, the ADH2-4c promoter, and the inducible GAL
promoter. Examples of suitable control sequences for use in
filamentous fungal host cells include the ADH3 promoter and
terminator, a promoter derived from the genes encoding Aspergillus
oryzae TAKA amylase triose phosphate isomerase or alkaline
protease, an A. niger .alpha.-amylase, A. niger or A. nidulans
glucoamylase, A. nidulans acetamidase, Rhizomucor miehei aspartic
proteinase or lipase, the TPI1 terminator and the ADH3 terminator.
Examples of suitable control sequences for use in bacterial host
cells include promoters of the lac system, the trp system, the TAC
or TRC system, and the major promoter regions of phage lambda.
[0256] The presence or absence of a signal peptide will, e.g.,
depend on the expression host cell used for the production of the
polypeptide variant to be expressed (whether it is an intracellular
or extracellular polypeptide) and whether it is desirable to obtain
secretion. For use in filamentous fungi, the signal peptide may
conveniently be derived from a gene encoding an Aspergillus sp.
amylase or glucoamylase, a gene encoding a Rhizomucor miehei lipase
or protease or a Humicola lanuginosa lipase. The signal peptide is
preferably derived from a gene encoding A. oryzae TAKA amylase, A.
niger neutral .alpha.-amylase, A. niger acid-stable amylase, or A.
niger glucoamylase. For use in insect cells, the signal peptide may
conveniently be derived from an insect gene (cf. WO 90/05783), such
as the Lepidopteran manduca sexta adipokinetic hormone precursor,
(cf. U.S. Pat. No. 5,023,328), the honeybee melittin (Invitrogen),
ecdysteroid UDPglucosyltransferase (egt) (Murphy et al., Protein
Expression and Purification 4, 349-357 (1993) or human pancreatic
lipase (hpl) (Methods in Enzymology 284, pp. 262-272, 1997). A
preferred signal peptide for use in mammalian cells is that of
hFVII or the murine Ig kappa light chain signal peptide (Coloma, M
(1992) J. Imm. Methods 152:89-104). For use in yeast cells suitable
signal peptides have been found to be the .alpha.-factor signal
peptide from S. cereviciae (cf. U.S. Pat. No. 4,870,008), a
modified carboxypeptidase signal peptide (cf. L. A. Valls et al.,
Cell 48, 1987, pp. 887-897), the yeast BAR1 signal peptide (cf. WO
87/02670), the yeast aspartic protease 3 (YAP3) signal peptide (cf.
M. Egel-Mitani et al., Yeast 6, 1990, pp. 127-137), and the
synthetic leader sequence TA57 (WO98/32867). For use in E. coli
cells a suitable signal peptide have been found to be the signal
peptide ompA (EP581821).
[0257] The nucleotide sequence of the invention encoding a
polypeptide variant, whether prepared by site-directed mutagenesis,
synthesis, PCR or other methods, may optionally include a
nucleotide sequence that encode a signal peptide. The signal
peptide is present when the polypeptide variant is to be secreted
from the cells in which it is expressed. Such signal peptide, if
present, should be one recognized by the cell chosen for expression
of the polypeptide variant. The signal peptide may, e.g. be that
normally associated with hFVII) or, alternatively, the signal
peptide may be from another source than hFVII, such as any of those
normally associated with other human wild-type vitamin K-dependent
polypeptides. Furthermore, the signal peptide may be a signal
peptide normally expressed from the host cell or one which is not
normally expressed from the host cell. Accordingly, the signal
peptide may be prokaryotic, e.g. derived from a bacterium such as
E. coli, or eukaryotic, e.g. derived from a mammalian, or insect or
yeast cell.
[0258] Any suitable host may be used to produce the polypeptide
variant, including bacteria (although not particularly preferred),
fungi (including yeasts), plant, insect, mammal, or other
appropriate animal cells or cell lines, as well as transgenic
animals or plants. Examples of bacterial host cells include
grampositive bacteria such as strains of Bacillus, e.g. B. brevis
or B. subtilis, Pseudomonas or Streptomyces, or gramnegative
bacteria, such as strains of E. coli. The introduction of a vector
into a bacterial host cell may, for instance, be effected by
protoplast transformation (see, e.g., Chang and Cohen, 1979,
Molecular General Genetics 168: 111-115), using competent cells
(see, e.g., Young and Spizizin, 1961, Journal of Bacteriology 81:
823-829, or Dubnau and Davidoff-Abelson, 1971, Journal of Molecular
Biology 56: 209-221), electroporation (see, e.g., Shigekawa and
Dower, 1988, Biotechniques 6: 742-751), or conjugation (see, e.g.,
Koehler and Thorne, 1987, Journal of Bacteriology 169: 5771-5278).
Examples of suitable filamentous fungal host cells include strains
of Aspergillus, e.g. A. oryzae, A. niger, or A. nidulans, Fusarium
or Trichoderma. Fungal cells may be transformed by a process
involving protoplast formation, transformation of the protoplasts,
and regeneration of the cell wall in a manner known per se.
Suitable procedures for transformation of Aspergillus host cells
are described in EP 238 023 and U.S. Pat. No. 5,679,543. Suitable
methods for transforming Fusarium species are described by
Malardier et al., 1989, Gene 78: 147-156 and WO 96/00787. Examples
of suitable yeast host cells include strains of Saccharomyces, e.g.
S. cerevisiae, Schizosaccharomyces, Klyveroinyces, Pichia, such as
P. pastoris or P. methzanolica, Hansenula, such as H. Polymorpha or
Yarrowia. Yeast may be transformed using the procedures described
by Becker and Guarente, In Abelson, J. N. and Simon, M. I.,
editors, Guide to Yeast Genetics and Molecular Biology, Methods in
Enzymology, Volume 194, pp 182-187, Academic Press, Inc., New York;
Ito et al., 1983, Journal of Bacteriology 153: 163; Hinnen et al.,
1978, Proceedings of the National Academy of Sciences USA 75: 1920:
and as disclosed by Clontech Laboratories, Inc, Palo Alto, Calif.,
USA (in the product protocol for the Yeastmaker.TM. Yeast
Transformation System Kit). Examples of suitable insect host cells
include a Lepidoptora cell line, such as Spodoptera frugiperda (Sf9
or Sf21) or Trichoplusioa ni cells (High Five) (U.S. Pat. No.
5,077,214). Transformation of insect cells and production of
heterologous polypeptides therein may be performed as described by
Invitrogen. Examples of suitable mammalian host cells include
Chinese hamster ovary (CHO) cell lines, (e.g. CHO-K1; ATCC CCL-61),
Green Monkey cell lines (COS) (e.g. COS 1 (ATCC CRL-1650), COS 7
(ATCC CRL-1651)); mouse cells (e.g. NS/O), Baby Hamster Kidney
(BHK) cell lines (e.g. ATCC CRL-1632 or ATCC CCL-10), and human
cells (e.g. HEK 293 (ATCC CRL-1573)), as well as plant cells in
tissue culture. Additional suitable cell lines are known in the art
and available from public depositories such as the American Type
Culture Collection, Rockville, Md. Also, the mammalian cell, such
as a CHO cell, may be modified to express sialyltransferase, e.g.
1,6-sialyltransferase, e.g. as described in U.S. Pat. No.
5,047,335, in order to provide improved glycosylation of the
polypeptide variant.
[0259] In order to increase secretion it may be of particular
interest to produce the polypeptide variant of the invention
together with an endoprotease, in particular a PACE (paired basic
amino acid converting enzyme) (e.g. as described in U.S. Pat. No.
5,986,079), such as a Kex2 endoprotease (e.g. as described in WO
00/28065).
[0260] Methods for introducing exogeneous DNA into mammalian host
cells include calcium phosphate-mediated transfection,
electroporation, DEAE-dextran mediated transfection,
liposome-mediated transfection, viral vectors and the transfection
method described by Life Technologies Ltd, Paisley, UK using
Lipofectamin 2000. These methods are well known in the art and e.g.
described by Ausbel et al. (eds.), 1996, Current Protocols in
Molecular Biology, John Wiley & Sons, New York, USA. The
cultivation of mammalian cells are conducted according to
established methods, e.g. as disclosed in (Animal Cell
Biotechnology, Methods and Protocols, Edited by Nigel Jenkins,
1999, Human Press Inc, Totowa, N.J., USA and Harrison M A and Rae I
F, General Techniques of Cell Culture, Cambridge University Press
1997).
[0261] In the production methods of the present invention, the
cells are cultivated in a nutrient medium suitable for production
of the polypeptide variant using methods known in the art. For
example, the cell may be cultivated by shake flask cultivation,
small-scale or large-scale fermentation (including continuous,
batch, fed-batch, or solid state fermentations) in laboratory or
industrial fermenters performed in a suitable medium and under
conditions allowing the polypeptide to be expressed and/or
isolated. The cultivation takes place in a suitable nutrient medium
comprising carbon and nitrogen sources and inorganic salts, using
procedures known in the art. Suitable media are available from
commercial suppliers or may be prepared according to published
compositions (e.g., in catalogues of the American Type Culture
Collection). If the polypeptide variant is secreted into the
nutrient medium, the polypeptide can be recovered directly from the
medium. If the polypeptide variant is not secreted, it can be
recovered from cell lysates.
[0262] The resulting polypeptide variant may be recovered by
methods known in the art. For example, the polypeptide variant may
be recovered from the nutrient medium by conventional procedures
including, but not limited to, centrifugation, filtration,
extraction, spray drying, evaporation, or precipitation.
[0263] The polypeptides may be purified by a variety of procedures
known in the art including, but not limited to, chromatography
(e.g., ion exchange, affinity, hydrophobic, chromatofocusing, and
size exclusion), electrophoretic procedures (e.g., preparative
isoelectric focusing), differential solubility (e.g., ammonium
sulfate precipitation), HPLC, or extraction (see, e.g., Protein
Purification, J.-C. Janson and Lars Ryden, editors, VCH Publishers,
New York, 1989).
[0264] Single chain polypeptide variants of the invention can be
purified and activated to two-chain polypeptide variants by a
number of methods as described in the literature (Broze and
Majerus, 1980, J. Biol. Chem. 255:1242-47 and Hedner and Kisiel,
1983, J. Clin. Invest. 71:1836-41). Another method whereby single
chain polypeptide variant can be purified is by incorporation of Zn
ions during purification as described in U.S. Pat. No. 5,700,914.
In a preferred embodiment the polypeptide variant is purified as a
single chain polypeptide variant. The single chain polypeptide
variant is activated by either use of an immobilized enzyme (e.g.
factors IIa, IXa, Xa and XIIa) or by autoactivation using a
positively charged ion exchange matrix or the like.
[0265] It is advantageous to first purify the polypeptide variant
in its single chain form, then PEGylate (if desired) and last
activate by one of the methods described above or by autoactivation
as described by Pedersen et al, 1989, Biochemistry 28: 9331-36. The
advantage of carrying out PEGylation before activation is that
PEGylation of the new aminoterminal formed by cleavage of R152-I153
is avoided. PEGylation of this new amino terminal would render the
molecule inactive since the formation of a hydrogen bond between
D242 and the amino terminal of I153 is necessary for activity.
Pharmaceutical Composition of the Invention and its Use
[0266] In a further aspect, the present invention relates to a
composition, in particular to a pharmaceutical composition,
comprising a polypeptide variant of the invention and a
pharmaceutically acceptable carrier or excipient.
[0267] The polypeptide variant or the pharmaceutical composition
according to the invention may be used as a medicament.
[0268] Due to the improved properties mentioned hereinbefore, the
polypeptide variants of the invention, or the pharmaceutical
composition of the invention, are particular useful for the
treatment of uncontrollable bleeding events in trauma patients,
thrombocytopenic patients, patients in anticoagulant treatment, and
cirrhosis patients with variceal bleeds, or other upper
gastrointestinal bleedings, and in patients undergoing orthotopic
liver transplantation, or liver resection (allowing for transfusion
free surgery).
[0269] Trauma is defined as an injury to living tissue caused by an
extrinsic agent. It is the 4.sup.th leading cause of death in the
US and places a large financial burden on the economy.
[0270] Trauma is classified as either blunt or penetrative. Blunt
trauma results in internal compression, organ damage and internal
haemorrhage whereas penetrative trauma (as the consequence of an
agent penetrating the body and destroying tissue, vessels and
organs) results in external haemorrhage.
[0271] Haemorrhage, as a result of trauma, can start a cascade of
problems. For example physiological compensation mechanisms are
initiated with initial peripheral and mesenteric vasoconstriction
to shunt blood to the central circulation. If circulation is not
restored, hypovolemia shock (multiple organ failure due to
inadequate perfusion) ensues. Since tissues throughout the body
become starved for oxygen, anaerobic metabolism begins. However,
the concomitant lactic acid leads the blood pH to drop and
metabolic acidosis develops. If acidosis is severe and uncorrected,
the patient may develop multisystem failure and die.
[0272] Although the majority of trauma patients are hypothermic on
arrival in the emergency room due to the environmental conditions
at the scene, inadequate protection, intravenous fluid
administration and ongoing blood loss worsen the hypothermic state.
Deficiencies in coagulation factors can result from blood loss or
transfusions. Meanwhile, acidosis and hypothermia interfere with
blood clotting mechanisms. Thus coagulopathy develops, which in
turn, may mask surgical bleeding sites and hamper the control of
mechanical bleeding.
[0273] Hypothermia, coagulopathy and acidosis are often
characterised as the "trauma triad of death"
[0274] Trauma may be caused by several events. For example, road
traffic accidents result in many different types of trauma. Whilst
some road traffic accidents are likely to result in penetrative
trauma, many road traffic accidents are likely to inflict blunt
trauma to both head and body. However, these various types of
trauma can all result in coagulopathy in the patient. Road traffic
accidents are the leading cause of accidental death in the US.
There are over 42,000 deaths from them in the US each year. Many
trauma patients die at the location of the accident either whilst
being treated by the paramedics, before they arrive or in transit
to the ER.
[0275] Another example includes gunshot wounds. Gunshot wounds are
traumas that can result in massive bleeding. They are penetrative
and destroy tissue as the bullet passes through the body, whether
it be in the torso or a limb. In the US about 40,000 people a year
die from gunshot wounds
[0276] A further example includes falls. Falls result in a similar
profile of trauma type to road traffic accidents. By falling onto a
solid object or the ground from height can cause both penetrative
and decelerative blunt trauma. In the US, falls are a common cause
of accidental death, numbering about 13,000.
[0277] A still further example includes machinery accidents. A
smaller number of people die in the US from machinery accident
related deaths, whether struck by, or entangled in machinery. The
figures are small but significant--around 2,000.
[0278] A still further example includes stab wounds. Stab wounds
are penetrative injuries that can also cause massive bleeding. The
organs most likely to be damaged in a stab wound are the liver,
small intestine and the colon.
[0279] Cirrhosis of the liver is the terminal sequel of prolonged
repeated injury to the hepatic parenchyma. The end result is the
formation of broad bands of fibrous tissue separating regenerative
nodules that do not maintain the normal organization of liver
lobules and thus cause deteriorated liver function. Patients have
prolonged prothrombin times as a result of the depletion of vitamin
K-dependent coagulation factors. Pathogenetically, liver cirrhosis
should be regarded as the final common pathway of chronic liver
injury, which can result from any form of intense repeated
prolonged liver cell injury. Cirrhosis of the liver may be caused
by direct liver injury, including chronic alcoholism, chronic viral
hepatitis (types B, C, and D), and auto immune hepatitis as well as
by indirect injury by way of bile duct damage, including primary
biliary cirrhosis, primary sclerosing cholangitis and biliary
atresia. Less common causes of cirrhosis include direct liver
injury from inherited disease such as cystic fibrosis,
alpha-1-antitrypsin deficiency, hemochromatosis, Wilson's disease,
galactosernia, and glycogen storage disease.
[0280] Transplantation is primarily reserved for late stage
cirrhotic patients, where it is the key intervention for treating
the disease. To be eligible for transplantation, a patient must be
classified as Child's B or C, as well as meet additional criteria
for selection. Last year, in the US alone, 4,954 transplants were
performed.
[0281] It has been estimated that there are 6,000 bleeding episodes
associated with patients undergoing resection each year. This
correlates with the reserved position of this procedure although
seems slightly high in comparison with transplantation numbers.
[0282] Accurate data on the incidence of variceal bleeding is hard
to obtain. The key facts known are that at the time of diagnosis,
varices are present in about 60% of decompensated and 30% of
compensated patients and that about 30% of these patients with
varices will experience a bleed and that each episode of variceal
bleeding is associated with a 30% risk of mortality.
[0283] Thus, in a further aspect the present invention relates to a
polypeptide variant of the invention for the manufacture of a
medicament for the treatment of diseases or disorder wherein clot
formation is desirable. A still further aspect of the present
invention relates to a method for treating a mammal having a
disease or disorder wherein clot formation is desirable, comprising
administering to a mammal in need thereof an effective amount of
the polypeptide variant or the pharmaceutical composition of the
invention.
[0284] Thrombocytopenia is caused by one of three
mechanisms-decreased bone marrow production, increased splenic
sequestration, or accelerated destruction of platelets.
Thronmbocytopenia is a risk factor for hemorrhage, and platelet
transfusion reduces the incidence of bleeding. The threshold for
prophylactic platelet transfusion is 10,000/.mu.l. In patients
without fever or infections, a threshold of 5000/.mu.l may be
sufficient to prevent spontaneous hemorrhage. For invasive
procedures, 50,000/.mu.l platelets is the usual target level. In
patients who develop antibodies to platelets following repeated
transfusions, bleeding can be extremely difficult to control.
[0285] Examples of diseases/disorders wherein increased clot
formation is desirable include, but is not limited to, hemorrhages,
including brain hemorrhages, as well as patient with severe
uncontrolled bleedings, such as trauma. Further examples include
patients undergoing living transplantations, patients undergoing
resection and patients with variceal bleedings.
[0286] The polypeptide variants of the invention is administered to
patients in a therapeutically effective dose, normally one
approximately paralleling that employed in therapy with rFVII such
as NovoSeven.RTM., or at lower dosage. By "therapeutically
effective dose" herein is meant a dose that is sufficient to
produce the desired effects in relation to the condition for which
it is administered. The exact dose will depend on the
circumstances, and will be ascertainable by one skilled in the art
using known techniques. Normally, the dose should be capable of
preventing or lessening the severity or spread of the condition or
indication being treated. It will be apparent to those of skill in
the art that an effective amount of a polypeptide variant or
composition of the invention depends, inter alia, upon the disease,
the dose, the administration schedule, whether the polypeptide
variant or composition is administered alone or in conjunction with
other therapeutic agents, the plasma half-life of the compositions,
and the general health of the patient. Preferably, the polypeptide
variant or composition of the invention is administered in an
effective dose, in particular a dose which is sufficient to
normalize the coagulation disorder.
[0287] The polypeptide variant of the invention is preferably
administered in a composition including a pharmaceutically
acceptable carrier or excipient. "Pharmaceutically acceptable"
means a carrier or excipient that does not cause any untoward
effects in patients to whom it is administered. Such
pharmaceutically acceptable carriers and excipients are well known
in the art (see, for example, Remington's Pharmaceutical Sciences,
18th edition, A. R. Gennaro, Ed., Mack Publishing Company [1990];
Pharmaceutical Formulation Development of Peptides and Proteins, S.
Frokjaer and L. Hovgaard, Eds., Taylor & Francis [2000]; and
Handbook of Pharmaceutical Excipients, 3rd edition, A. Kibbe, Ed.,
Pharmaceutical Press [2000]).
[0288] The polypeptide variant of the invention can be formulated
into pharmaceutical compositions by well-known methods. Suitable
formulations are described by Remington's Pharmaceutical Sciences
by E. W. Martin (Mark Publ. Co., 16th Ed., 1980).
[0289] The polypeptide variant of the invention can be used "as is"
and/or in a salt form thereof. Suitable salts include, but are not
limited to, salts with alkali metals or alkaline earth metals, such
as sodium, potassium, calcium and magnesium, as well as e.g. zinc
salts. These salts or complexes may by present as a crystalline
and/or amorphous structure.
[0290] The pharmaceutical composition of the invention may be
administered alone or in conjunction with other therapeutic agents.
These agents may be incorporated as part of the same pharmaceutical
composition or may be administered separately from the polypeptide
variant of the invention, either concurrently or in accordance with
another treatment schedule. In addition, the polypeptide variant or
pharmaceutical composition of the invention may be used as an
adjuvant to other therapies.
[0291] A "patient" for the purposes of the present invention
includes both humans and other mammals. Thus, the methods are
applicable to both human therapy and veterinary applications. The
pharmaceutical composition comprising the polypeptide variant of
the invention may be formulated in a variety of forms, e.g. as a
liquid, gel, lyophilized, or as a compressed solid. The preferred
form will depend upon the particular indication being treated and
will be apparent to one skilled in the art.
[0292] In particular, the pharmaceutical composition comprising the
polypeptide variant of the invention may be formulated in
lyophilised or stable soluble form. The polypeptide variant may be
lyophilised by a variety of procedures known in the art. The
polypeptide variant may be in a stable soluble form by the removal
or shielding of proteolytic degradation sites as described herein.
The advantage of obtaining a stable soluble preparation lies in
easier handling for the patient and, in the case of emergencies,
quicker action, which potentially can become life saving. The
preferred form will depend upon the particular indication being
treated and will be apparent to one of skill in the art.
[0293] The administration of the formulations of the present
invention can be performed in a variety of ways, including, but not
limited to, orally, subcutaneously, intravenously, intracerebrally,
intranasally, transdermally, intraperitoneally, intramuscularly,
intrapulmonary, vaginally, rectally, intraocularly, or in any other
acceptable manner. The formulations can be administered
continuously by infusion, although bolus injection is acceptable,
using techniques well known in the art, such as pumps or
implantation. In some instances the formulations may be directly
applied as a solution or spray.
Parentals
[0294] A preferred example of a pharmaceutical composition is a
solution designed for parenteral administration. Although in many
cases pharmaceutical solution formulations are provided in liquid
form, appropriate for immediate use, such parenteral formulations
may also be provided in frozen or in lyophilized form. In the
former case, the composition must be thawed prior to use. The
latter form is often used to enhance the stability of the active
compound contained in the composition under a wider variety of
storage conditions, as it is recognized by those skilled in the art
that lyophilized preparations are generally more stable than their
liquid counterparts. Such lyophilized preparations are
reconstituted prior to use by the addition of one or more suitable
pharmaceutically acceptable diluents such as sterile water for
injection or sterile physiological saline solution.
[0295] In case of parenterals, they are prepared for storage as
lyophilized formulations or aqueous solutions by mixing, as
appropriate, the polypeptide variant having the desired degree of
purity with one or more pharmaceutically acceptable carriers,
excipients or stabilizers typically employed in the art (all of
which are termed "excipients"), for example buffering agents,
stabilizing agents, preservatives, isotonifiers, non-ionic
surfactants or detergents, antioxidants and/or other miscellaneous
additives.
[0296] Buffering agents help to maintain the pH in the range which
approximates physiological conditions. They are typically present
at a concentration ranging from about 2 mM to about 50 mM. Suitable
buffering agents for use in the present invention include both
organic and inorganic acids and salts thereof such as citrate
buffers (e.g., monosodium citrate-disodium citrate mixture, citric
acid-trisodium citrate mixture, citric acid-monosodium citrate
mixture, etc.), succinate buffers (e.g., succinic acid-monosodium
succinate mixture, succinic acid-sodium hydroxide mixture, succinic
acid-disodium succinate mixture, etc.), tartrate buffers (e.g.,
tartaric acid-sodium tartrate mixture, tartaric acid-potassium
tartrate mixture, tartaric acid-sodium hydroxide mixture, etc.),
fumarate buffers (e.g., fumaric acid-monosodium fumarate mixture,
fumaric acid-disodium fumarate mixture, monosodium
fumarate-disodium fumarate mixture, etc.), gluconate buffers (e.g.,
gluconic acid-sodium glyconate mixture, gluconic acid-sodium
hydroxide mixture, gluconic acid-potassium glyuconate mixture,
etc.), oxalate buffer (e.g., oxalic acid-sodium oxalate mixture,
oxalic acid-sodium hydroxide mixture, oxalic acid-potassium oxalate
mixture, etc.), lactate buffers (e.g., lactic acid-sodium lactate
mixture, lactic acid-sodium hydroxide mixture, lactic
acid-potassium lactate mixture, etc.) and acetate buffers (e.g.,
acetic acid-sodium acetate mixture, acetic acid-sodium hydroxide
mixture, etc.). Additional possibilities are phosphate buffers,
histidine buffers and trimethylamine salts such as Tris.
[0297] Stabilizers refer to a broad category of excipients, which
can range in function from a bulking agent to an additive which
solubilizes the therapeutic agent or helps to prevent denaturation
or adherence to the container wall. Typical stabilizers can be
polyhydric sugar alcohols (enumerated above); amino acids such as
arginine, lysine, glycine, glutamine, asparagine, histidine,
alanine, ornithine, L-leucine, 2-phenylalanine, glutamic acid,
threonine, etc., organic sugars or sugar alcohols, such as lactose,
trehalose, stachyose, mannitol, sorbitol, xylitol, ribitol,
myoinisitol, galactitol, glycerol and the like, including cyclitols
such as inositol; polyethylene glycol; amino acid polymers;
sulfur-containing reducing agents, such as urea, glutathione,
thioctic acid, sodium thioglycolate, thioglycerol,
.alpha.-monothioglycerol and sodium thiosulfate; low molecular
weight polypeptides (i.e. <10 residues); proteins such as human
serum albumin, bovine serum albumin, gelatin or immunoglobulins;
hydrophilic polymers such as polyvinylpyrrolidone; monosaccharides
such as xylose, mannose, fructose and glucose; disaccharides such
as lactose, maltose and sucrose; trisaccharides such as raffinose,
and polysaccharides such as dextran. Stabilizers are typically
present in the range of from 0.1 to 10,000 parts by weight based on
the active protein weight.
[0298] Preservatives are added to retard microbial growth, and are
typically added in amounts of about 0.2%-1% (w/v). Suitable
preservatives for use with the present invention include phenol,
benzyl alcohol, meta-cresol, methyl paraben, propyl paraben,
octadecyldimethylbenzyl ammonium chloride, benzalkonium halides
(e.g. benzalkonium chloride, bromide or iodide), hexamethonium
chloride, alkyl parabens such as methyl or propyl paraben,
catechol, resorcinol, cyclohexanol and 3-pentanol.
[0299] Isotonicifiers are added to ensure isotonicity of liquid
compositions and include polyhydric sugar alcohols, preferably
trihydric or higher sugar alcohols, such as glycerin, erythritol,
arabitol, xylitol, sorbitol and mannitol. Polyhydric alcohols can
be present in an amount between 0.1% and 25% by weight, typically
1% to 5%, taking into account the relative amounts of the other
ingredients.
[0300] Non-ionic surfactants or detergents (also known as "wetting
agents") may be present to help solubilizing the therapeutic agent
as well as to protect the therapeutic polypeptide against
agitation-induced aggregation, which also permits the formulation
to be exposed to shear surface stress without causing denaturation
of the polypeptide. Suitable non-ionic surfactants include
polysorbates (20, 80, etc.), polyoxamers (184, 188 etc.),
Pluronic.RTM. polyols, polyoxyethylene sorbitan monoethers
(Tween.RTM.-20, Tween.RTM.-80, etc.). Additional miscellaneous
excipients include bulking agents or fillers (e.g. starch),
chelating agents (e.g. EDTA), antioxidants (e.g., ascorbic acid,
methionine, vitamin E) and cosolvents.
[0301] The active ingredient may also be entrapped in microcapsules
prepared, for example, by coascervation techniques or by
interfacial polymerization, for example hydroxymethylcellulose,
gelatin or poly-(methylmethacylate) microcapsules, in colloidal
drug delivery systems (for example liposomes, albumin micro
spheres, microemulsions, nano-particles and nanocapsules) or in
macroemulsions. Such techniques are disclosed in Remington's
Pharmaceutical Sciences, supra.
[0302] Parenteral formulations to be used for in vivo
administration must be sterile. This is readily accomplished, for
example, by filtration through sterile filtration membranes.
Sustained Release Preparations
[0303] Examples of sustained-release preparations include
semi-permeable matrices of solid hydrophobic polymers containing
the polypeptide variant, the matrices having a suitable form such
as a film or microcapsules. Examples of sustained-release matrices
include polyesters, hydrogels (for example,
poly(2-hydroxyethyl-methacrylate) or poly(vinylalcohol)),
polylactides, copolymers of L-glutamic acid and ethyl-L-glutamate,
non-degradable ethylene-vinyl acetate, degradable lactic
acid-glycolic acid copolymers such as the ProLease.RTM. technology
or Lupron Depot.RTM. (injectable microspheres composed of lactic
acid-glycolic acid copolymer and leuprolide acetate), and
poly-D-(-)-3-hydroxybutyric acid. While polymers such as
ethylene-vinyl acetate and lactic acid-glycolic acid enable release
of molecules for long periods such as up to or over 100 days,
certain hydrogels release proteins for shorter time periods. When
encapsulated polypeptides remain in the body for a long time, they
may denature or aggregate as a result of exposure to moisture at
37.degree. C., resulting in a loss of biological activity and
possible changes in immunogenicity. Rational strategies can be
devised for stabilization is depending on the mechanism involved.
For example, if the aggregation mechanism is discovered to be
intermolecular S--S bond formation through thio-disulfide
interchange, stabilization may be achieved by modifying sulfhydryl
residues, lyophilizing from acidic solutions, controlling moisture
content, using appropriate additives, and developing specific
polymer matrix compositions.
[0304] The invention is further described in the following
non-limiting examples.
Materials and Methods
Accessible Surface Area (ASA)
[0305] The computer program Access (B. Lee and F. M. Richards, J.
Mol. Biol. 55: 379-400 (1971)) version 2 (.COPYRGT. 1983 Yale
University) is used to compute the accessible surface area (ASA) of
the individual atoms in the structure. This method typically uses a
probe-size of 1.4 .ANG. and defines the Accessible Surface Area
(ASA) as the area formed by the center of the probe. Prior to this
calculation all water molecules and all hydrogen atoms should be
removed from the coordinate set, as should other atoms not directly
related to the protein.
Fractional ASA of Side Chain
[0306] The fractional ASA of the side chain atoms is computed by
division of the sum of the ASA of the atoms in the side chain with
a value representing the ASA of the side chain atoms of that
residue type in an extended Ala-x-Ala tripeptide (See Hubbard,
Campbell & Thornton (1991) J. Mol. Biol. 220,507-530). For this
example the CA atom is regarded as a part of the side chain of
Glycine residues but not for the remaining residues. The following
table is used as standard 100% ASA for the side chain:
TABLE-US-00003 Ala 69.23 .ANG..sup.2 Arg 200.35 .ANG..sup.2 Asn
106.25 .ANG..sup.2 Asp 102.06 .ANG..sup.2 Cys 96.69 .ANG..sup.2 Gln
140.58 .ANG..sup.2 Glu 134.61 .ANG..sup.2 Gly 32.28 .ANG..sup.2 His
147.00 .ANG..sup.2 Ile 137.91 .ANG..sup.2 Leu 140.76 .ANG..sup.2
Lys 162.50 .ANG..sup.2 Met 156.08 .ANG..sup.2 Phe 163.90
.ANG..sup.2 Pro 119.65 .ANG..sup.2 Ser 78.16 .ANG..sup.2 Thr 101.67
.ANG..sup.2 Trp 210.89 .ANG..sup.2 Tyr 176.61 .ANG..sup.2 Val
114.14 .ANG..sup.2
[0307] Residues not detected in the structure are defined as having
100% exposure as they are thought to reside in flexible regions.
The gamma-carboxy glutamic acids at positions 6, 7, 14, 16, 19, 20,
25, 26, 29 and 35 are all defined as being 100% exposed.
Determining Distances Between Atoms
[0308] The distance between atoms is most easily determined using
molecular graphics software e.g. InsightII.RTM. v. 98.0, MSI
INC.
Active Site Region
[0309] The active site region is defined as any residues having at
least one atom within 10 .ANG. of any atom in the catalytic triad
(residues H193, D242, S344).
Determination of Tissue Factor Binding Site
[0310] The TF binding site is defined as comprising of all residues
having their accessible surface area changed upon TF binding. This
is determined by at least two ASA calculations; one on the isolated
ligand(s) in the ligand(s)/receptor(s) complex and one on the
complete ligand(s)/receptor(s) complex.
Measurement of Reduced Sensitivity to Proteolytic Degradation
[0311] Proteolytic degradation can be measured using the assay
described in U.S. Pat. No. 5,580,560, Example 5, where proteolysis
is autoproteolysis.
[0312] Furthermore, reduced proteolysis can be tested in an in vivo
model using radiolabelled samples and comparing proteolysis of
rhFVIIa and the polypeptide variant of the invention by withdrawing
blood samples and subjecting these to SDS-PAGE and
autoradiography.
[0313] Irrespectively of the assay used for determining proteolytic
degradation, "reduced proteolytic degradation" is intended to mean
a measurable reduction in cleavage compared to is that obtained by
rhFVIIa as measured by gel scanning of Coomassie stained SDS-PAGE
gels, HPLC or as measured by conserved catalytic activity in
comparison to wild type using the tissue factor independent
activity assay decribed below.
Determination of the Molecular Weight of Polypeptide Variants
[0314] The molecular weight of polypeptide variants is determined
by either SDS-PAGE, get filtration, Western Blots, matrix assisted
laser desorption mass spectrometry or equilibrium centrifugation,
e.g. SDS-PAGE according to Laemmli, U.K., Nature Vol 227 (1970),
pp. 680-85.
TF-Independent Factor X Activation Assay
[0315] This assay has been described in detail on page 39826 in
Nelsestuen et al., J Biol Chem, 2001; 276:39825-39831.
[0316] Briefly, the molecule to be assayed (either hFVIIa, rhFVIIa
or the polypeptide variant of the invention in its activated form)
is mixed with a source of phospholipid (phosphatidylcholine and
phosphatidylserine in a ratio of 8:2 or phosphatidyleholine,
phosphatidylserine and phosphatidylethanol in a ratio of 4:2:4) and
Factor X in Tris buffer containing BSA. After a specified
incubation time the reaction is stopped by addition of excess EDTA.
The concentration of factor Xa is then measured from absorbance
change at 405 nm after addition of a chromogenic substrate (S-2222,
Chromogenix). After correction from background the tissue factor
independent activity of rhFVIIa (a.sub.wt) is determined as the
absorbance change after 10 minutes and the tissue factor
independent activity of the polypeptide variant of the invention
(a.sub.variant) is also determined as the absorbance change after
10 minutes. The ratio between the activity of the polypeptide
variant, in its activated form, and the activity of rhFVIIa is
defined as a.sub.variant/a.sub.wt.
Clotting Assay
[0317] Clotting activity is measured in one-stage assays and
clotting times are recorded on a Thrombotrack IV coagulometer
(MEDINOR). FVII depleted human plasma (American Diagnostica) is
reconstituted and equilibrated at room temperature for 15-20
minutes. 50 .mu.l of plasma is then transferred to the coagulometer
cups.
[0318] hFVIIa, rhFVIIa or variants are diluted in Glyoxaline Buffer
(5.7 mM barbiturate, 4.3 mM sodium citrate, 117 mM NaCl, 1 mg/mL
BSA, pH 7.35). The samples are added to the cup in 50 .mu.l and
incubated at 37.degree. C. for 2 minutes.
[0319] Thromboplastin (MEDINOR) is reconstituted with water and
CaCl.sub.2 is added. The reaction is initiated by adding 0.1 ml
thromboplastin containing 4.5 mM CaCl.sub.2.
[0320] Data are analysed using PRISM software.
TF-Independent Clotting Assay
[0321] This assay is performed as described above under "Clotting
Assay" but without addition of thromboplastin.
Amidolytic Assay
[0322] The ability of the variants to cleave small peptide
substrates can be measured using the chromogenic substrate S-2288
(D-Ile-Pro-Arg-p-nitroanilide). The amidolytic activity may be
measured both in the presence and absence of antithrombin III
(ATIII).
[0323] HFVIIa, rhFVIIa or variant is diluted to 90 nM in assay
buffer (50 mM Na-Hepes pH 7.5, 150 mM NaCl, 5 mM CaCl.sub.2, 0.1%
BSA, 1U/ml Heparin). Furthermore, soluble TF (sTF) is diluted to
450 nM in assay buffer. ATIII is diluted to 900 nM in assay buffer.
120 .mu.l of assay buffer is mixed with 20 .mu.l of the FVIIa
sample, 20 .mu.l sTF and 20 .mu.l ATIII or assay buffer. The final
concentrations of FVIIa, sTF and ATIII are 10, 50 and 100 nM,
respectively. After 5 min incubation at room temperature with
gentle shaking, followed by 10 min incubation at 37.degree. C., the
reaction is started by addition of the S-2288 substrate to 1 mM and
the absorption at 405 nm is determined at several time points.
Thrombogram Assay
[0324] The effect of hFVIIa, rhFVIIa or variant on thrombin
generation in human plasma is tested in a modified version of the
assay described on page 589 in Hemker et al. in Thromb Haemost
2000; 83: 589-91. Briefly, the molecule to be assayed (either
hFVIIa, rhFVIIa or variant) is mixed with normal platelet rich
plasma (PRP), normal platelet poor plasma (PPP) or FVII depleted
PPP with or without the addition of recombinant human tissue factor
(rTF), relipidated rTF or another source of TF (such as
thromboplastin). A source of phospholipid (phosphatidylcholine and
phosphatidylserine in a ratio of 8:2 or phosphatidylcholine,
phosphatidylserine and phosphatidylethanol in a ratio of 4:2:4) can
be added.
[0325] The reaction is started by addition of a fluoregenic
thrombin substrate and calcium chloride. The fluorescence is
measured continuously and the thrombin amidolytic activity is
calculated by calculating the slope of the fluorescence curve (the
increase in fluorescence over time). In this way the time until
maximum thrombin amidolytic activity is obtained (T.sub.max) and
total thrombin work (area under the curve (AUC)) can be
calculated.
[0326] The following procedure is used: PRP is obtained by
centrifuging freshly drawn blood at 250 g, 15.degree. C. for 10
min. Blood coagulation is inhibited either by using citrate (13 mM
tri-sodium citrate), corn trypsin inhibitor (50-100 .mu.g/ml blood)
or a combination of citrate and corn trypsin inhibitor. The
platelet count is adjusted to 3.times.10.sup.8/mL using buffer or
autologous platelet poor plasma (PPP). PPP is obtained by double
centrifugation of PRP at 1000 g, 15.degree. C. for 10 min. FVII
depletion is done by incubating PPP with a FVII specific monoclonal
antibody coupled to a solid phase.
[0327] Per well of a 96-well microtiter plate 80 .mu.l PRP is added
and 20 .mu.L buffer containing rhFVII or variant to be tested in
final concentrations between 0.1 and 100 nM. rTF is added in 5
.mu.L assay buffer to a final concentration of 1 pM. The assay
buffer consists of 20 mM Hepes, 150 mM NaCl and 60 mg/ml BSA in
distilled water. The reaction is started by adding 20 .mu.L of the
substrate solution containing 0.1 M calcium chloride. The assay
plate and reagents are prewarmed to 37.degree. C. and the reaction
takes place at this temperature. The fluorimeter used is a BMG
Fluormeter with a excitation filter at 390 nm and an emission
filter at 460 nm. The fluorescence is measured in each well of
96-well clear bottom plates in 20-40 second interval over 30-180
minutes. Data are analyzed using PRISM Software.
ELISA Assay
[0328] FVII/FVIIa (or variant) concentrations are determined by
ELISA. Wells of a microtiter late are coated with an antibody
directed against the protease domain using a solution of 2 .mu.g/ml
in PBS (100 .mu.l per well). After 2 hours coating at R.T., the
wells are washed 4 times with THT buffer (100 mM NaCl, 50 mM
Tris-HCl pH 7.2 0.05% Tween-20). Subsequently, 200 .mu.l of 1%
Casein (diluted from 2.5% stock using 100 mM NaCl, 50 mM Tris-HCl
pH 7.2) is added per well for blocking. After 1 hr incubation at
R.T., the wells are emptied, and 100 .mu.l of sample (optionally
diluted in dilution buffer (THT+0.1% Casein)) is added. After
another incubation of 1 hr at room temperature, the wells are
washed 4 times with THT buffer, and 100 .mu.l of a biotin-labelled
antibody directed against the EGF-like domain (1 .mu.g/ml) is
added. After another 1 hr incubation at R.T., followed by 4 more
washes with THT buffer, 100 .mu.l of streptavidin-horse radish
peroxidase (DAKO A/S, Glostrup, Denmark, 1/10000 diluted) is added.
After another 1 hr incubation at R.T., followed by 4 more washes
with THT buffer, 100 .mu.l of TMB (3,3',5,5'-tetramethylbenzidine,
Kem-en-Tech A/S, Denmark) is added. After 30 min incubation at R.T.
in the dark, 100 .mu.l of 1 M H.sub.2SO.sub.4 is added and
OD.sub.450nm is determined. A standard curve is prepared using
rhFVIIa (NovoSeven.RTM.).
[0329] Alternatively, FVII/FVIIa or variants may be quantified
through the Gla domain rather than through the protease domain. In
this ELISA set-up, wells are coated overnight with an antibody
directed against the EGF-like domain and for detection, a
calcium-dependent biotin-labelled monoclonal anti-Gla domain
antibody is used (2 .mu.g/ml, 100 .mu.l per well). In this set-up,
5 mM CaCl.sub.2 is added to the THT and dilution buffers.
Whole Blood Assay
[0330] The whole blood clotting assay is performed as described by
Elg et al. Thrombosis Res. 2001, 101(3):159-170.
Reconstituted Coagulation Assay
[0331] The reconstituted coagulation assay is performed as
described by Van't Veer et al. Blood 2000, 95(4), 1330-1335.
EXAMPLES
Example 1
[0332] The X-ray structure of hFVIIa in complex with soluble tissue
factor by Banner et. al., J Mol Biol, 1996; 285:2089 is used for
this example. It is noted that the numbering of residues in the
reference does not follow the sequence. Here we have used the
sequential numbering according to SEQ ID NO:2. The gamma-carboxy
glutamic acids at positions 6, 7, 14, 16, 19, 20, 25, 26, 29 and 35
are all here named GLU (three letter abbreviation) or E (one letter
abbreviation). Residues 143-152 are not present in the
structure.
Surface Exposure
[0333] Performing fractional ASA calculations on FVII fragments
alone combined with the definition of accessibilities of non
standard and/or missing residues described in the methods resulted
in the following residues having more than 25% of their side chain
exposed to the surface: A1, N2, A3, F4, L5, E6, E7, L8, R9, P10,
S12, L13, E14, E16, K18, E19, E20, Q21, S23, F24, E25, E26, R8,
E29, F31, K32, D33, A34, E35, R36, K38, L39, W41, I42, S43, S45,
G47, D48, Q49, A51, S52, S53, Q56, G58, S60, K62, D63, Q64, L65,
Q66, S67, I69, F71, L73, P74, A75, E77, G78, R79, E82, T83, H84,
K85, D86, D87, Q88, L89, I90, V92, N93, E94, G97, E99, S103, D104,
H105, T106, G107, T108, K109, S111, R113, E116, G117, S119, L120,
L121, A122, D123, G124, V125, S126, T128, P129, T130, V131, E132,
1140, L141, E142, K143, R144, N145, A146, S147, K148, P149, Q150,
G151, R152, G155, K157, V158, P160, K161, E163, L171, N173, G174,
A175, N184, T185, 1186, H193, K197, K199, N200, R202, N203, 1205,
S214, E215, H216, D217, G218, D219, S222, R224, S232, T233, V235,
P236, G237, T238, T239, N240, H249, Q250, P251, V253, T255, D256,
E265, R266, T267, E270, R271, F275, V276, R277, F278, L280, L287,
L288, D289, R290, G291, A292, T293, L295, E296, N301, M306, T307,
Q308, D309, L311, Q312, Q313, R315, K316, V317, G318, D319, S320,
P321, N322, T324, E325, Y326, Y332, S333, D334, S336, K337, K341,
G342, H351, R353, G354, Q366, G367, T370, V371, G372, R379, E385,
Q388, K389, R392, S393, E394, P395, R396, P397, G398, V399, L400,
L401, R402, P404 and P406 (A1-S45 are located in the Gla domain,
the remaining positions are located outside the Gla domain).
[0334] The following residues had more than 50% of their side chain
exposed to the surface: A1, A3, F4, L5, E6, E7, L8, R9, P10, E14,
E16, K18, E19, E20, Q21, S23, E25, E26, E29, K32, A34, E35, R36,
K38, L39, I42, S43, G47, D48, A51, S52, S53, Q56, G58, S60, K62,
L65, Q66, S67, I69, F71, L73, P74, A75, E77, G78, R79, E82, H84,
K85, D86, D87, Q88, L89, I90, V92, N93, E94, G97, T106, G107, T108,
K109, S111, E116, S119, L121, A122, D123, G124, V131, E132, L141,
E142, K143, R144, N145, A146, S147, K148, P149, Q150, G151, R152,
G155, K157, P160, N173, G174, A175, K197, K199, N200, R202, S214,
E215, H216, G218, R224, V235, P236, G237, T238, H249, Q250, V253,
D256, T267, F275, R277, F278, L288, D289, R290, G291, A292, T293,
L295, N301, M306, Q308, D309, L311, Q312, Q313, R315, K316, G318,
D319, N322, E325, D334, K341, G354, G367, V371, E385, K389, R392,
E394, R396, P397, G398, R402, P404 and P406 (A1-S43 are located in
the Gla domain, the remaining positions are located outside the Gla
domain).
Tissue Factor Binding Site
[0335] Performing ASA calculations the following residues in human
FVII change their ASA in the complex. These residues were defined
as constituting the receptor binding site: L13, K18, F31, E35, R36,
L39, F40, I42, S43, S60, K62, D63, Q64, L65, I69, C70, F71, C72,
L73, P74, F76, E77, G78, R79, E82, K85, Q88, I90, V92, N93, E94,
R271, A274, F275, V276, R277, F278, R304, L305, M306, T307, Q308,
D309, Q312, Q313, E325 and R379.
Active Site Region
[0336] The active site region is defined as any residue having at
least one atom within a distance of 10 .ANG. from any atom in the
catalytic triad (residues H193, D242, S344): I153, Q167, V168,
L169, L170, L171, Q176, L177, C178, G179, G180, T181, V188, V189,
S190, A191, A192, H193, C194, F195, D196, K197, 1198, W201, V228,
I229, I230, P231, S232, T233, Y234, V235, P236, G237, T238, T239,
N240, H241, D242, I243, A244, L245, L246, V281, S282, G283, W284,
G285, Q286, T293, T324, E325, Y326, M327, F328, D338, S339, C340,
K341, G342, D343, S344, G345, G346, P347, H348, L358, T359, G360,
I361, V362, S363, W364, G365, C368, V376, Y377, T378, R379, V380,
Q382, Y383, W386, L387, L400 and F405.
The Ridge of the Active Site Binding Cleft
[0337] The ridge of the active site binding cleft region was
defined by visual inspection of the FVIIa structure 1FAK.pdb as:
N173, A175, K199, N200, N203, D289, R290, G291, A292, P321 and
T370.
Example 2
Design of an Expression Cassette for Expression of rhFVII in
Mammalian Cells
[0338] The DNA sequence shown in SEQ ID NO:1, encompassing the
short form of the full length cDNA encoding hFVII with its native
short signal peptide (Hagen et al., 1986. PNAS 83:2412), was
synthesized in order to facilitate high expression in mammalian
cells. First the ATG start codon context was modified according to
the Kozak consensus sequence (Kozak, M. J Mol Biol 1987 Aug. 20;
196(4):947-50), so that there is a perfect match to the consensus
sequence upstream of the ATG start codon. Secondly the open reading
frame of the native cDNA was modified by making a bias in the codon
usage towards the codons frequently used in highly expressed human
genes. Further, two translational stop codons were inserted at the
end of the open reading frame in order to facilitate efficient
translational stop. The fully synthetic and expression optimized
hFVII gene was assembled from 70-mer DNA oligonucleotides and
finally amplified using end primers inserting BamHI and HindIII
sites at the 5' and 3' ends respectively using standard PCR
techniques, which resulted in the following sequence:
TABLE-US-00004 ggatcccgccaccatggtcagccaggccctccgcctcctgtgcctgctcc
tggggctgcagggctgcctggctgccgtcttcgtcacccaggaggaagcc
catggcgtcctgcatcgccggcgccgggccaatgcctttctggaagagct
ccgccctggctccctggaacgcgaatgcaaagaggaacagtgcagctttg
aggaagcccgggagattttcaaagacgctgagcggaccaaactgttttgg
attagctatagcgatggcgatcagtgcgcctccagcccttgccagaacgg
gggctcctgcaaagaccagctgcagagctatatctgcttctgcctgcctg
cctttgaggggcgcaattgcgaaacccataaggatgaccagctgatttgc
gtcaacgaaaacgggggctgcgagcagtactgcagcgatcacacgggcac
gaagcggagctgccgctgccacgaaggctatagcctcctggctgacgggt
gtcctgcacgcccacggtggaatacccttgcgggaagattcccattctag
aaaagcggaacgctagcaaaccccagggccggatcgtcggcgggaaggtc
tgccctaagggggagtgcccctggcaggtcctgctcctggtcaacggggc
ccagctgtgcggcgggaccctcatcaataccatttgggtcgtgtccgccg
ctcactgcttcgataagattaagaattggcggaacctcatcgctgtgctc
ggcgaacacgatctgtccgagcatgacggggacgaacagtcccgccgggt
ggctcaggtcatcattccctccacctatgtgcctggcacgaccaatcacg
atatcgctctgctccgcctccaccagcccgtcgtgctcaccgatcacgtc
gtgcctctgttgcctgcctgagcggaccttagcgaacgcacgctggcttt
cgtccgctttagctctcgtgtccggctggggccagctgctcgaccggggc
gctaccgctctcgagctgatggtgctcaacgtcccccggctgatgaccca
ggactgcctgcagcagtcccgcaaagtgggggactcccccaatatcacgg
agtatatgttttgcgctggctatagcgatggctccaaggatagctgcaag
ggggactccggcgggccccatgccacgcactatcgcgggacctggtacct
caccgggatcgtcagctggggccagggctgcgccaacggtggggcacttt
ggcgtctacacgcgcgtcagccagtacattgagtggctgcagaagctcat
gcggagcgaaccccggcccggggtgctcctgcgggcccctttcccttgat aaaagctt
[0339] A vector for the cloning of the generated PCR product
encompassing the expression cassette for hFVII was prepared by
cloning the intron from pCINeo (Promega). The synthetic intron from
pCI-Neo was amplified using standard PCR conditions and the
primers: TABLE-US-00005 CBProFpr174:
5'-AGCTGGCTAGCCACTGGGCAGGTAAGTATCA-3' and CBProFpr175:
5'-TGGCGGGATCCTTAAGAGCTGTAATTGAACT-3'
resulting in a 332 bp PCR fragment. The fragment was cut with NheI
and BamHI before cloning into pCDNA3.1/HygR (obtained from
Invitrogen) resulting in PF#34.
[0340] The expression cassette for hFVII was cloned between the
BamHI and HindIII sites of PF434, resulting in plasmid PF#226.
Example 3
Expression of Polypeptide Variants in CHO K1 Cells
[0341] The cell line CHO K1 (ATCC # CCL-61) is seeded at 50%
confluence in T-25 flasks using MEM.alpha., 10% FCS (Gibco/BRL Cat
# 10091), P/S and 5 .mu.g/ml phylloquinone and allowed to grow
until confluent. The confluent mono cell layer is transfected with
5 .mu.g of the relevant plasmid described above using the
Lipofectamine 2000 transfection agent (Life technologies) according
to the manufacturer's instructions. Twenty four hours post
transfection a sample is drawn and quantified using e.g. an ELISA
recognizing the EGF1 domain of hFVII. At this time point relevant
selection (e.g. Hygromycin B) may be applied to the cells with the
purpose of generating a pool of stable transfectants. When using
CHO K1 cells and the Hygromycin B resistance gene as selectable
marker on the plasmid, this is usually achieved within one
week.
Example 4
Generation of CHO K1 Cells Stably Expressing Polypeptide
Variants.
[0342] A vial of CHO-K1 transfectant pool is thawed and the cells
seeded in a 175 cm.sup.2 tissue flask containing 25 ml of
MEM.alpha., 10% FCS, phylloquinone (5 .mu.g/ml), 100 U/l
penicillin, 100 .mu.g/l streptomycin and grown for 24 hours. The
cells are harvested, diluted and plated in 96 well microtiter
plates at a cell density of 1/2-1 cell/well. After a week of
growth, colonies of 20-100 cells are present in the wells and those
wells containing only one colony are labelled. After a further two
weeks, the media in all wells containing only one colony is
substituted with 200 .mu.l fresh medium. After 24 hours, a medium
sample is withdrawn and analysed by e.g. ELISA. High producing
clones are selected and used to produce FVII or variant on large
scale.
Example 5
Purification of Polypeptide Variants and Subsequent Activation
[0343] FVII and FVII variants are purified as follows: The
procedure is performed at 4.degree. C. The harvested culture media
from large-scale production is ultrafiltered using a Millipore TFF
system with 30 KDa cut-off Pellicon membranes. After concentration
of the medium, citrate is added to 5 mM and the pH is adjusted to
8.6. If necessary, the conductivity is lowered to below 10 mS/cm.
Subsequently, the sample is applied to a Q-sepharose FF column,
equilibrated with 50 mM NaCl, 10 mM Tris pH 8.6. After washing the
column with 100 mM NaCl, 10 mM Tris pH 8.6, followed by 150 mM
NaCl, 10 mM Tris pH 8.6, FVII is eluted using 10 mM Tris, 25 mM
NaCl, 35 mM CaCl.sub.2, pH 8.6.
[0344] For the second chromatographic step, an affinity column is
prepared by coupling of a monoclonal Calcium-dependent
antiGla-domain antibody to CNBr-activated Sepharose FF. About 5.5
mg antibody is coupled per ml resin. The column is equilibrated
with 10 mM Tris, 100 mM NaCl, 35 mM CaCl.sub.2, pH 7.5. NaCl is
added to the sample to a concentration of 100 mM NaCl and the pH is
adjusted to 7.4-7.6. After O/N application of the sample, the
column is washed with 100 mM NaCl, 35 mM CaCl.sub.2, 10 mM Tris pH
7.5, and the FVII protein is eluted with 100 mM NaCl, 50 mM
citrate, 75 mM Tris pH 7.5.
[0345] For the third chromatographic, the conductivity of the
sample is lowered to below 10 mS/cm, if necessary, and the pH is
adjusted to 8.6. The sample is then applied to a Q-sepharose column
(equilibrated with 50 mM NaCl, 10 mM Tris pH 8.6) at a density
around 3-5 mg protein per ml gel to obtain efficient activation.
After application, the column is washed with 50 mM NaCl, 10 mM Tris
pH 8.6 for about 4 hours with a flow of 3-4 column volumes (cv) per
hour. The FVII protein is eluted using a gradient of 0-100% of 500
mM NaCl, 10 mM Tris pH 8.6 over 40 cv. FVII containing fractions
are pooled.
[0346] For the final chromatographic step, the conductivity is
lowered to below 10 mS/cm. Subsequently, the sample is applied to a
Q-sepharose column (equilibrated with 140 mM NaCl, 10 mM
glycylglycine pH 8.6) at a concentration of 3-5 mg protein per ml
gel. The column is then washed with 140 mM NaCl, 10 mM
glycylglycine pH 8.6 and FVII is eluted with 140 mM NaCl, 15 mM
CaCl.sub.2, 10 mM glycylglycine pH 8.6. The eluate is diluted to 10
mM CaCl.sub.2 and the pH is adjusted 6.8-7.2. Finally, Tween-80 is
added to 0.01% and the pH is adjusted to 5.5 for storage at
-80.degree. C.
Sequence CWU 1
1
4 1 1338 DNA Homo sapiens CDS (115)..(1335) 1 atggtcagcc aggccctccg
cctcctgtgc ctgctcctgg ggctgcaggg ctgcctggct 60 gccgtcttcg
tcacccagga ggaagcccat ggcgtcctgc atcgccggcg ccgg gcc 117 Ala 1 aat
gcc ttt ctg gaa gag ctc cgc cct ggc tcc ctg gaa cgc gaa tgc 165 Asn
Ala Phe Leu Glu Glu Leu Arg Pro Gly Ser Leu Glu Arg Glu Cys 5 10 15
aaa gag gaa cag tgc agc ttt gag gaa gcc cgg gag att ttc aaa gac 213
Lys Glu Glu Gln Cys Ser Phe Glu Glu Ala Arg Glu Ile Phe Lys Asp 20
25 30 gct gag cgg acc aaa ctg ttt tgg att agc tat agc gat ggc gat
cag 261 Ala Glu Arg Thr Lys Leu Phe Trp Ile Ser Tyr Ser Asp Gly Asp
Gln 35 40 45 tgc gcc tcc agc cct tgc cag aac ggg ggc tcc tgc aaa
gac cag ctg 309 Cys Ala Ser Ser Pro Cys Gln Asn Gly Gly Ser Cys Lys
Asp Gln Leu 50 55 60 65 cag agc tat atc tgc ttc tgc ctg cct gcc ttt
gag ggg cgc aat tgc 357 Gln Ser Tyr Ile Cys Phe Cys Leu Pro Ala Phe
Glu Gly Arg Asn Cys 70 75 80 gaa acc cat aag gat gac cag ctg att
tgc gtc aac gaa aac ggg ggc 405 Glu Thr His Lys Asp Asp Gln Leu Ile
Cys Val Asn Glu Asn Gly Gly 85 90 95 tgc gag cag tac tgc agc gat
cac acg ggc acg aag cgg agc tgc cgc 453 Cys Glu Gln Tyr Cys Ser Asp
His Thr Gly Thr Lys Arg Ser Cys Arg 100 105 110 tgc cac gaa ggc tat
agc ctc ctg gct gac ggg gtg tcc tgc acg ccc 501 Cys His Glu Gly Tyr
Ser Leu Leu Ala Asp Gly Val Ser Cys Thr Pro 115 120 125 acg gtg gaa
tac cct tgc ggg aag att ccc att cta gaa aag cgg aac 549 Thr Val Glu
Tyr Pro Cys Gly Lys Ile Pro Ile Leu Glu Lys Arg Asn 130 135 140 145
gct agc aaa ccc cag ggc cgg atc gtc ggc ggg aag gtc tgc cct aag 597
Ala Ser Lys Pro Gln Gly Arg Ile Val Gly Gly Lys Val Cys Pro Lys 150
155 160 ggg gag tgc ccc tgg cag gtc ctg ctc ctg gtc aac ggg gcc cag
ctg 645 Gly Glu Cys Pro Trp Gln Val Leu Leu Leu Val Asn Gly Ala Gln
Leu 165 170 175 tgc ggc ggg acc ctc atc aat acc att tgg gtc gtg tcc
gcc gct cac 693 Cys Gly Gly Thr Leu Ile Asn Thr Ile Trp Val Val Ser
Ala Ala His 180 185 190 tgc ttc gat aag att aag aat tgg cgg aac ctc
atc gct gtg ctc ggc 741 Cys Phe Asp Lys Ile Lys Asn Trp Arg Asn Leu
Ile Ala Val Leu Gly 195 200 205 gaa cac gat ctg tcc gag cat gac ggg
gac gaa cag tcc cgc cgg gtg 789 Glu His Asp Leu Ser Glu His Asp Gly
Asp Glu Gln Ser Arg Arg Val 210 215 220 225 gct cag gtc atc att ccc
tcc acc tat gtg cct ggc acg acc aat cac 837 Ala Gln Val Ile Ile Pro
Ser Thr Tyr Val Pro Gly Thr Thr Asn His 230 235 240 gat atc gct ctg
ctc cgc ctc cac cag ccc gtc gtg ctc acc gat cac 885 Asp Ile Ala Leu
Leu Arg Leu His Gln Pro Val Val Leu Thr Asp His 245 250 255 gtc gtg
cct ctg tgc ctg cct gag cgg acc ttt agc gaa cgc acg ctg 933 Val Val
Pro Leu Cys Leu Pro Glu Arg Thr Phe Ser Glu Arg Thr Leu 260 265 270
gct ttc gtc cgc ttt agc ctc gtg tcc ggc tgg ggc cag ctg ctc gac 981
Ala Phe Val Arg Phe Ser Leu Val Ser Gly Trp Gly Gln Leu Leu Asp 275
280 285 cgg ggc gct acc gct ctc gag ctg atg gtg ctc aac gtc ccc cgg
ctg 1029 Arg Gly Ala Thr Ala Leu Glu Leu Met Val Leu Asn Val Pro
Arg Leu 290 295 300 305 atg acc cag gac tgc ctg cag cag tcc cgc aaa
gtg ggg gac tcc ccc 1077 Met Thr Gln Asp Cys Leu Gln Gln Ser Arg
Lys Val Gly Asp Ser Pro 310 315 320 aat atc acg gag tat atg ttt tgc
gct ggc tat agc gat ggc tcc aag 1125 Asn Ile Thr Glu Tyr Met Phe
Cys Ala Gly Tyr Ser Asp Gly Ser Lys 325 330 335 gat agc tgc aag ggg
gac tcc ggc ggg ccc cat gcc acg cac tat cgc 1173 Asp Ser Cys Lys
Gly Asp Ser Gly Gly Pro His Ala Thr His Tyr Arg 340 345 350 ggg acc
tgg tac ctc acc ggg atc gtc agc tgg ggc cag ggc tgc gcc 1221 Gly
Thr Trp Tyr Leu Thr Gly Ile Val Ser Trp Gly Gln Gly Cys Ala 355 360
365 acg gtg ggg cac ttt ggc gtc tac acg cgc gtc agc cag tac att gag
1269 Thr Val Gly His Phe Gly Val Tyr Thr Arg Val Ser Gln Tyr Ile
Glu 370 375 380 385 tgg ctg cag aag ctc atg cgg agc gaa ccc cgg ccc
ggg gtg ctc ctg 1317 Trp Leu Gln Lys Leu Met Arg Ser Glu Pro Arg
Pro Gly Val Leu Leu 390 395 400 cgg gcc cct ttc cct tga taa 1338
Arg Ala Pro Phe Pro 405 2 406 PRT Homo sapiens 2 Ala Asn Ala Phe
Leu Glu Glu Leu Arg Pro Gly Ser Leu Glu Arg Glu 1 5 10 15 Cys Lys
Glu Glu Gln Cys Ser Phe Glu Glu Ala Arg Glu Ile Phe Lys 20 25 30
Asp Ala Glu Arg Thr Lys Leu Phe Trp Ile Ser Tyr Ser Asp Gly Asp 35
40 45 Gln Cys Ala Ser Ser Pro Cys Gln Asn Gly Gly Ser Cys Lys Asp
Gln 50 55 60 Leu Gln Ser Tyr Ile Cys Phe Cys Leu Pro Ala Phe Glu
Gly Arg Asn 65 70 75 80 Cys Glu Thr His Lys Asp Asp Gln Leu Ile Cys
Val Asn Glu Asn Gly 85 90 95 Gly Cys Glu Gln Tyr Cys Ser Asp His
Thr Gly Thr Lys Arg Ser Cys 100 105 110 Arg Cys His Glu Gly Tyr Ser
Leu Leu Ala Asp Gly Val Ser Cys Thr 115 120 125 Pro Thr Val Glu Tyr
Pro Cys Gly Lys Ile Pro Ile Leu Glu Lys Arg 130 135 140 Asn Ala Ser
Lys Pro Gln Gly Arg Ile Val Gly Gly Lys Val Cys Pro 145 150 155 160
Lys Gly Glu Cys Pro Trp Gln Val Leu Leu Leu Val Asn Gly Ala Gln 165
170 175 Leu Cys Gly Gly Thr Leu Ile Asn Thr Ile Trp Val Val Ser Ala
Ala 180 185 190 His Cys Phe Asp Lys Ile Lys Asn Trp Arg Asn Leu Ile
Ala Val Leu 195 200 205 Gly Glu His Asp Leu Ser Glu His Asp Gly Asp
Glu Gln Ser Arg Arg 210 215 220 Val Ala Gln Val Ile Ile Pro Ser Thr
Tyr Val Pro Gly Thr Thr Asn 225 230 235 240 His Asp Ile Ala Leu Leu
Arg Leu His Gln Pro Val Val Leu Thr Asp 245 250 255 His Val Val Pro
Leu Cys Leu Pro Glu Arg Thr Phe Ser Glu Arg Thr 260 265 270 Leu Ala
Phe Val Arg Phe Ser Leu Val Ser Gly Trp Gly Gln Leu Leu 275 280 285
Asp Arg Gly Ala Thr Ala Leu Glu Leu Met Val Leu Asn Val Pro Arg 290
295 300 Leu Met Thr Gln Asp Cys Leu Gln Gln Ser Arg Lys Val Gly Asp
Ser 305 310 315 320 Pro Asn Ile Thr Glu Tyr Met Phe Cys Ala Gly Tyr
Ser Asp Gly Ser 325 330 335 Lys Asp Ser Cys Lys Gly Asp Ser Gly Gly
Pro His Ala Thr His Tyr 340 345 350 Arg Gly Thr Trp Tyr Leu Thr Gly
Ile Val Ser Trp Gly Gln Gly Cys 355 360 365 Ala Thr Val Gly His Phe
Gly Val Tyr Thr Arg Val Ser Gln Tyr Ile 370 375 380 Glu Trp Leu Gln
Lys Leu Met Arg Ser Glu Pro Arg Pro Gly Val Leu 385 390 395 400 Leu
Arg Ala Pro Phe Pro 405 3 31 DNA Artificial Sequence Description of
Artificial Sequence Primer CBProFpr174 3 agctggctag ccactgggca
ggtaagtatc a 31 4 31 DNA Artificial Sequence Description of
Artificial Sequence Primer CBProFpr175 4 tggcgggatc cttaagagct
gtaattgaac t 31
* * * * *