U.S. patent application number 17/477889 was filed with the patent office on 2021-12-30 for anti-pd-1 antibodies and uses thereof.
The applicant listed for this patent is Eucure (Beijing) Biopharma Co., Ltd. Invention is credited to Yunyun Chen, Xiaodong Cheng, Chunyan Dong, Yanan Guo, Chengyuan Lu, Jian Ni, Yuelei Shen, Jingshu Xie, Fang Yang, Yi Yang.
Application Number | 20210403570 17/477889 |
Document ID | / |
Family ID | 1000005839424 |
Filed Date | 2021-12-30 |
United States Patent
Application |
20210403570 |
Kind Code |
A1 |
Yang; Yi ; et al. |
December 30, 2021 |
ANTI-PD-1 ANTIBODIES AND USES THEREOF
Abstract
This disclosure relates to anti-PD-1 (Programmed Cell Death
Protein 1) antibodies, antigen-binding fragments, and the uses
thereof.
Inventors: |
Yang; Yi; (Beijing, CN)
; Xie; Jingshu; (Beijing, CN) ; Dong; Chunyan;
(Beijing, CN) ; Yang; Fang; (Beijing, CN) ;
Lu; Chengyuan; (Beijing, CN) ; Cheng; Xiaodong;
(Beijing, CN) ; Shen; Yuelei; (Beijing, CN)
; Ni; Jian; (Beijing, CN) ; Guo; Yanan;
(Beijing, CN) ; Chen; Yunyun; (Beijing,
CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Eucure (Beijing) Biopharma Co., Ltd |
Beijing |
|
CN |
|
|
Family ID: |
1000005839424 |
Appl. No.: |
17/477889 |
Filed: |
September 17, 2021 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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16919846 |
Jul 2, 2020 |
11155625 |
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17477889 |
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PCT/CN2018/077016 |
Feb 23, 2018 |
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16919846 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C07K 2317/92 20130101;
C07K 2317/622 20130101; A61K 2039/505 20130101; C07K 2317/565
20130101; C07K 2317/33 20130101; C07K 16/2818 20130101; A61P 35/00
20180101; C07K 2317/24 20130101; C07K 2317/94 20130101 |
International
Class: |
C07K 16/28 20060101
C07K016/28; A61P 35/00 20060101 A61P035/00 |
Claims
1. An antibody or antigen-binding fragment thereof that binds to
PD-1 (Programmed Cell Death Protein 1) comprising: a heavy chain
variable region (VH) comprising complementarity determining regions
(CDRs) 1, 2, and 3, wherein the VH CDR1 region comprises an amino
acid sequence that is at least 80% identical to a selected VH CDR1
amino acid sequence, the VH CDR2 region comprises an amino acid
sequence that is at least 80% identical to a selected VH CDR2 amino
acid sequence, and the VH CDR3 region comprises an amino acid
sequence that is at least 80% identical to a selected VH CDR3 amino
acid sequence; and a light chain variable region (VL) comprising
CDRs 1, 2, and 3, wherein the VL CDR1 region comprises an amino
acid sequence that is at least 80% identical to a selected VL CDR1
amino acid sequence, the VL CDR2 region comprises an amino acid
sequence that is at least 80% identical to a selected VL CDR2 amino
acid sequence, and the VL CDR3 region comprises an amino acid
sequence that is at least 80% identical to a selected VL CDR3 amino
acid sequence, wherein the selected VH CDRs 1, 2, and 3 amino acid
sequences and the selected VL CDRs, 1, 2, and 3 amino acid
sequences are one of the following: (1) the selected VH CDRs 1, 2,
3 amino acid sequences are set forth in SEQ ID NOs: 1, 2, 3,
respectively, and the selected VL CDRs 1, 2, 3 amino acid sequences
are set forth in SEQ ID NOs: 4, 5, 6, respectively; (2) the
selected VH CDRs 1, 2, 3 amino acid sequences are set forth in SEQ
ID NOs: 7, 8, 9, respectively, and the selected VL CDRs 1, 2, 3
amino acid sequences are set forth in SEQ ID NOs: 10, 11, 12,
respectively; (3) the selected VH CDRs 1, 2, 3 amino acid sequences
are set forth in SEQ ID NOs: 7, 13, 14, respectively, and the
selected VL CDRs 1, 2, 3 amino acid sequences are set forth in SEQ
ID NOs: 10, 11, 15, respectively.
2. The antibody or antigen-binding fragment thereof of claim 1,
wherein the VH comprises CDRs 1, 2, 3 with the amino acid sequences
set forth in SEQ ID NOs: 1, 2, and 3 respectively, and the VL
comprises CDRs 1, 2, 3 with the amino acid sequences set forth in
SEQ ID NOs: 4, 5, and 6, respectively.
3. The antibody or antigen-binding fragment thereof of claim 1,
wherein the VH comprises CDRs 1, 2, 3 with the amino acid sequences
set forth in SEQ ID NOs: 7, 8, and 9, respectively, and the VL
comprises CDRs 1, 2, 3 with the amino acid sequences set forth in
SEQ ID NOs: 10, 11, and 12, respectively.
4. The antibody or antigen-binding fragment thereof of claim 1,
wherein the VH comprises CDRs 1, 2, 3 with the amino acid sequences
set forth in SEQ ID NOs: 7, 13, and 14, respectively, and the VL
comprises CDRs 1, 2, 3 with the amino acid sequences set forth in
SEQ ID NOs: 10, 11, and 15, respectively.
5. The antibody or antigen-binding fragment thereof of any one of
claims 1-4, wherein the antibody or antigen-binding fragment
specifically binds to human PD-1.
6. The antibody or antigen-binding fragment thereof of any one of
claims 1-5, wherein the antibody or antigen-binding fragment is a
humanized antibody or antigen-binding fragment thereof.
7. The antibody or antigen-binding fragment thereof of any one of
claims 1-6, wherein the antibody or antigen-binding fragment is a
single-chain variable fragment (scFV).
8. A nucleic acid comprising a polynucleotide encoding a
polypeptide comprising: (1) an immunoglobulin heavy chain or a
fragment thereof comprising a heavy chain variable region (VH)
comprising complementarity determining regions (CDRs) 1, 2, and 3
comprising the amino acid sequences set forth in SEQ ID NOs: 1, 2,
and 3, respectively, and wherein the VH, when paired with a light
chain variable region (VL) comprising the amino acid sequence set
forth in SEQ ID NO: 29, 30, 31, or 40, binds to PD-1; (2) an
immunoglobulin light chain or a fragment thereof comprising a VL
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 4, 5, and 6, respectively, and wherein the VL,
when paired with a VH comprising the amino acid sequence set forth
in SEQ ID NO: 26, 27, 28, or 39, binds to PD-1; (3) an
immunoglobulin heavy chain or a fragment thereof comprising a heavy
chain variable region (VH) comprising CDRs 1, 2, and 3 comprising
the amino acid sequences set forth in SEQ ID NOs: 7, 8, and 9,
respectively, and wherein the VH, when paired with a light chain
variable region (VL) comprising the amino acid sequence set forth
in SEQ ID NO: 36, 37, 38 or 42, binds to PD-1; (4) an
immunoglobulin light chain or a fragment thereof comprising a VL
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 10, 11, and 12, respectively, and wherein the
VL, when paired with a VH comprising the amino acid sequence set
forth in SEQ ID NO: 32, 33, 34, 35 or 41, binds to PD-1; (5) an
immunoglobulin heavy chain or a fragment thereof comprising a heavy
chain variable region (VH) comprising CDRs 1, 2, and 3 comprising
the amino acid sequences set forth in SEQ ID NOs: 7, 13, and 14,
respectively, and wherein the VH, when paired with a light chain
variable region (VL) comprising the amino acid sequence set forth
in SEQ ID NO: 44 binds to PD-1; (6) an immunoglobulin light chain
or a fragment thereof comprising a VL comprising CDRs 1, 2, and 3
comprising the amino acid sequences set forth in SEQ ID NOs: 10,
11, and 15, respectively, and wherein the VL, when paired with a VH
comprising the amino acid sequence set forth in SEQ ID NO: 43 binds
to PD-1.
9. The nucleic acid of claim 8, wherein the nucleic acid comprises
a polynucleotide encoding a polypeptide comprising an
immunoglobulin heavy chain or a fragment thereof comprising a VH
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 1, 2, and 3, respectively.
10. The nucleic acid of claim 8, wherein the nucleic acid comprises
a polynucleotide encoding a polypeptide comprising an
immunoglobulin light chain or a fragment thereof comprising a VL
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 4, 5, and 6, respectively.
11. The nucleic acid of claim 8, wherein the nucleic acid comprises
a polynucleotide encoding a polypeptide comprising an
immunoglobulin heavy chain or a fragment thereof comprising a VH
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 7, 8, and 9, respectively.
12. The nucleic acid of claim 8, wherein the nucleic acid comprises
a polynucleotide encoding a polypeptide comprising an
immunoglobulin light chain or a fragment thereof comprising a VL
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 10, 11, and 12, respectively.
13. The nucleic acid of claim 8, wherein the nucleic acid comprises
a polynucleotide encoding a polypeptide comprising an
immunoglobulin heavy chain or a fragment thereof comprising a VH
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 7, 13, and 14, respectively.
14. The nucleic acid of claim 8, wherein the nucleic acid comprises
a polynucleotide encoding a polypeptide comprising an
immunoglobulin light chain or a fragment thereof comprising a VL
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 10, 11, and 15, respectively.
15. The nucleic acid of any one of claims 8-14, wherein the VH when
paired with a VL specifically binds to human PD-1, or the VL when
paired with a VH specifically binds to human PD-1.
16. The nucleic acid of any one of claims 8-15, wherein the
immunoglobulin heavy chain or the fragment thereof is a humanized
immunoglobulin heavy chain or a fragment thereof, and the
immunoglobulin light chain or the fragment thereof is a humanized
immunoglobulin light chain or a fragment thereof.
17. The nucleic acid of any one of claims 8-16, wherein the nucleic
acid encodes a single-chain variable fragment (scFv).
18. The nucleic acid of any one of claims 8-17, wherein the nucleic
acid is cDNA.
19. A vector comprising one or more of the nucleic acids of any one
of claims 8-18.
20. A vector comprising two of the nucleic acids of any one of
claims 8-18, wherein the vector encodes the VL region and the VH
region that together bind to PD-1.
21. A pair of vectors, wherein each vector comprises one of the
nucleic acids of any one of claims 8-18, wherein together the pair
of vectors encodes the VL region and the VH region that together
bind to PD-1.
22. A cell comprising the vector of claim 19 or 20, or the pair of
vectors of claim 21.
23. The cell of claim 22, wherein the cell is a CHO cell.
24. A cell comprising one or more of the nucleic acids of any one
of claims 8-18.
25. A cell comprising two of the nucleic acids of any one of claims
8-18.
26. The cell of claim 25, wherein the two nucleic acids together
encode the VL region and the VH region that together bind to
PD-1.
27. A method of producing an antibody or an antigen-binding
fragment thereof, the method comprising (a) culturing the cell of
any one of claims 22-26 under conditions sufficient for the cell to
produce the antibody or the antigen-binding fragment; and (b)
collecting the antibody or the antigen-binding fragment produced by
the cell.
28. An antibody or antigen-binding fragment thereof that binds to
PD-1 comprising a heavy chain variable region (VH) comprising an
amino acid sequence that is at least 90% identical to a selected VH
sequence, and a light chain variable region (VL) comprising an
amino acid sequence that is at least 90% identical to a selected VL
sequence, wherein the selected VH sequence and the selected VL
sequence are one of the following: (1) the selected VH sequence is
SEQ ID NOs: 26, 27, 28, or 39, and the selected VL sequence is SEQ
ID NOs: 29, 30, 31, or 40; (2) the selected VH sequence is SEQ ID
NOs: 32, 33, 34, 35 or 41, and the selected VL sequence is SEQ ID
NOs: 36, 37, 38 or 42; (3) the selected VH sequence is SEQ ID NO:
43, and the selected VL sequence is SEQ ID NO: 44.
29. The antibody or antigen-binding fragment thereof of claim 28,
wherein the VH comprises the sequence of SEQ ID NO: 26 and the VL
comprises the sequence of SEQ ID NO: 31.
30. The antibody or antigen-binding fragment thereof of claim 28,
wherein the VH comprises the sequence of SEQ ID NO: 27 and the VL
comprises the sequence of SEQ ID NO: 31.
31. The antibody or antigen-binding fragment thereof of any one of
claims 28-31, wherein the antibody or antigen-binding fragment
specifically binds to human PD-1.
32. The antibody or antigen-binding fragment thereof of any one of
claims 28-32, wherein the antibody or antigen-binding fragment is a
humanized antibody or antigen-binding fragment thereof.
33. The antibody or antigen-binding fragment thereof of any one of
claims 28-30, wherein the antibody or antigen-binding fragment is a
single-chain variable fragment (scFV).
34. An antibody-drug conjugate comprising the antibody or
antigen-binding fragment thereof of any one of claims 1-7 and 28-33
covalently bound to a therapeutic agent.
35. The antibody drug conjugate of claim 34, wherein the
therapeutic agent is a cytotoxic or cytostatic agent.
36. A method of treating a subject having cancer, the method
comprising administering a therapeutically effective amount of a
composition comprising the antibody or antigen-binding fragment
thereof of any one of claims 1-7 and 28-33, or the antibody-drug
conjugate of claim 34 or 35, to the subject.
37. The method of claim 36, wherein the subject has a solid
tumor.
38. The method of claim 36, wherein the cancer is unresectable
melanoma or metastatic melanoma.
39. The method of claim 36, wherein the cancer is non-small cell
lung cancer (NSCLC), squamous cell carcinoma of the head and neck
(SCCHN), head and neck cancer, renal cell carcinoma (RCC),
melanoma, bladder cancer, gastric cancer, urothelial cancer,
Merkel-cell carcinoma, triple-negative breast cancer (TNBC), or
colorectal carcinoma.
40. A method of decreasing the rate of tumor growth, the method
comprising contacting a tumor cell with an effective amount of a
composition comprising an antibody or antigen-binding fragment
thereof of any one of claims 1-7 and 28-33, or the antibody-drug
conjugate of claims 34 or 35.
41. A method of killing a tumor cell, the method comprising
contacting a tumor cell with an effective amount of a composition
comprising the antibody or antigen-binding fragment thereof of any
one of claims 1-7 and 28-33, or the antibody-drug conjugate of
claims 34 or 35.
42. A pharmaceutical composition comprising the antibody or
antigen-binding fragment thereof of any one of claims 1-7 and
28-33, and a pharmaceutically acceptable carrier.
43. A pharmaceutical composition comprising the antibody drug
conjugate of claim 34 or 35, and a pharmaceutically acceptable
carrier.
Description
CLAIM OF PRIORITY
[0001] This application is a divisional of U.S. application Ser.
No. 16/919,846, filed on Jul. 2, 2020, which claims priority to
International Application No. PCT/CN2018/077016, filed on Feb. 23,
2018. The entire contents of the foregoing are incorporated herein
by reference.
TECHNICAL FIELD
[0002] This disclosure relates to anti-PD-1 (Programmed Cell Death
Protein 1) antibodies and uses thereof.
STATEMENT REGARDING SEQUENCE LISTING
[0003] The Sequence Listing associated with this application is
provided in text form in lieu of a paper copy, and is hereby
incorporated by reference into the specification. The name of the
text file containing the Sequence Listing is 45124-0016002_SL.txt.
The text file is 34.0 KB, and was created and submitted
electronically via EFS-Web on May 24, 2021.
BACKGROUND
[0004] Cancer is currently one of the diseases that have the
highest human mortality. According to the World Health Organization
statistical data, in 2012, the number of global cancer incidence
and death cases reached 14 million and 8.2 million, respectively.
In China, the newly diagnosed cancer cases are 3.07 million, and
the death toll is 2.2 million.
[0005] Recent clinical and commercial success of anticancer
antibodies has created great interest in antibody-based
therapeutics. There is a need to develop anti-cancer antibodies for
use in various antibody-based therapeutics to treat cancers.
SUMMARY
[0006] This disclosure relates to anti-PD-1 antibodies,
antigen-binding fragment thereof, and the uses thereof.
[0007] In one aspect, the disclosure relates to an antibody or
antigen-binding fragment thereof that binds to PD-1 (Programmed
Cell Death Protein 1) comprising: a heavy chain variable region
(VH) comprising complementarity determining regions (CDRs) 1, 2,
and 3, wherein the VH CDR1 region comprises an amino acid sequence
that is at least 80% identical to a selected VH CDR1 amino acid
sequence, the VH CDR2 region comprises an amino acid sequence that
is at least 80% identical to a selected VH CDR2 amino acid
sequence, and the VH CDR3 region comprises an amino acid sequence
that is at least 80% identical to a selected VH CDR3 amino acid
sequence; and a light chain variable region (VL) comprising CDRs 1,
2, and 3, wherein the VL CDR1 region comprises an amino acid
sequence that is at least 80% identical to a selected VL CDR1 amino
acid sequence, the VL CDR2 region comprises an amino acid sequence
that is at least 80% identical to a selected VL CDR2 amino acid
sequence, and the VL CDR3 region comprises an amino acid sequence
that is at least 80% identical to a selected VL CDR3 amino acid
sequence, wherein the selected VH CDRs 1, 2, and 3 amino acid
sequences and the selected VL CDRs, 1, 2, and 3 amino acid
sequences are one of the following:
[0008] (1) the selected VH CDRs 1, 2, 3 amino acid sequences are
set forth in SEQ ID NOs: 1, 2, 3, respectively, and the selected VL
CDRs 1, 2, 3 amino acid sequences are set forth in SEQ ID NOs: 4,
5, 6, respectively;
[0009] (2) the selected VH CDRs 1, 2, 3 amino acid sequences are
set forth in SEQ ID NOs: 7, 8, 9, respectively, and the selected VL
CDRs 1, 2, 3 amino acid sequences are set forth in SEQ ID NOs: 10,
11, 12, respectively;
[0010] (3) the selected VH CDRs 1, 2, 3 amino acid sequences are
set forth in SEQ ID NOs: 7, 13, 14, respectively, and the selected
VL CDRs 1, 2, 3 amino acid sequences are set forth in SEQ ID NOs:
10, 11, 15, respectively.
[0011] In some embodiments, the VH comprises CDRs 1, 2, 3 with the
amino acid sequences set forth in SEQ ID NOs: 1, 2, and 3
respectively, and the VL comprises CDRs 1, 2, 3 with the amino acid
sequences set forth in SEQ ID NOs: 4, 5, and 6, respectively.
[0012] In some embodiments, the VH comprises CDRs 1, 2, 3 with the
amino acid sequences set forth in SEQ ID NOs: 7, 8, and 9,
respectively, and the VL comprises CDRs 1, 2, 3 with the amino acid
sequences set forth in SEQ ID NOs: 10, 11, and 12,
respectively.
[0013] In some embodiments, the VH comprises CDRs 1, 2, 3 with the
amino acid sequences set forth in SEQ ID NOs: 7, 13, and 14,
respectively, and the VL comprises CDRs 1, 2, 3 with the amino acid
sequences set forth in SEQ ID NOs: 10, 11, and 15,
respectively.
[0014] In some embodiments, the antibody or antigen-binding
fragment specifically binds to human PD-1. In some embodiments, the
antibody or antigen-binding fragment is a humanized antibody or
antigen-binding fragment thereof. In some embodiments, the antibody
or antigen-binding fragment is a single-chain variable fragment
(scFV).
[0015] In another aspect, the disclosure relates to a nucleic acid
comprising a polynucleotide encoding a polypeptide comprising:
[0016] (1) an immunoglobulin heavy chain or a fragment thereof
comprising a heavy chain variable region (VH) comprising
complementarity determining regions (CDRs) 1, 2, and 3 comprising
the amino acid sequences set forth in SEQ ID NOs: 1, 2, and 3,
respectively, and wherein the VH, when paired with a light chain
variable region (VL) comprising the amino acid sequence set forth
in SEQ ID NO: 29, 30, 31, or 40, binds to PD-1; [0017] (2) an
immunoglobulin light chain or a fragment thereof comprising a VL
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 4, 5, and 6, respectively, and wherein the VL,
when paired with a VH comprising the amino acid sequence set forth
in SEQ ID NO: 26, 27, 28, or 39, binds to PD-1; [0018] (3) an
immunoglobulin heavy chain or a fragment thereof comprising a heavy
chain variable region (VH) comprising CDRs 1, 2, and 3 comprising
the amino acid sequences set forth in SEQ ID NOs: 7, 8, and 9,
respectively, and wherein the VH, when paired with a light chain
variable region (VL) comprising the amino acid sequence set forth
in SEQ ID NO: 36, 37, 38 or 42, binds to PD-1; [0019] (4) an
immunoglobulin light chain or a fragment thereof comprising a VL
comprising CDRs 1, 2, and 3 comprising the amino acid sequences set
forth in SEQ ID NOs: 10, 11, and 12, respectively, and wherein the
VL, when paired with a VH comprising the amino acid sequence set
forth in SEQ ID NO: 32, 33, 34, 35 or 41, binds to PD-1; [0020] (5)
an immunoglobulin heavy chain or a fragment thereof comprising a
heavy chain variable region (VH) comprising CDRs 1, 2, and 3
comprising the amino acid sequences set forth in SEQ ID NOs: 7, 13,
and 14, respectively, and wherein the VH, when paired with a light
chain variable region (VL) comprising the amino acid sequence set
forth in SEQ ID NO: 44 binds to PD-1; [0021] (6) an immunoglobulin
light chain or a fragment thereof comprising a VL comprising CDRs
1, 2, and 3 comprising the amino acid sequences set forth in SEQ ID
NOs: 10, 11, and 15, respectively, and wherein the VL, when paired
with a VH comprising the amino acid sequence set forth in SEQ ID
NO: 43 binds to PD-1.
[0022] In some embodiments, the nucleic acid comprises a
polynucleotide encoding a polypeptide comprising an immunoglobulin
heavy chain or a fragment thereof comprising a VH comprising CDRs
1, 2, and 3 comprising the amino acid sequences set forth in SEQ ID
NOs: 1, 2, and 3, respectively.
[0023] In some embodiments, the nucleic acid comprises a
polynucleotide encoding a polypeptide comprising an immunoglobulin
light chain or a fragment thereof comprising a VL comprising CDRs
1, 2, and 3 comprising the amino acid sequences set forth in SEQ ID
NOs: 4, 5, and 6, respectively.
[0024] In some embodiments, the nucleic acid comprises a
polynucleotide encoding a polypeptide comprising an immunoglobulin
heavy chain or a fragment thereof comprising a VH comprising CDRs
1, 2, and 3 comprising the amino acid sequences set forth in SEQ ID
NOs: 7, 8, and 9, respectively.
[0025] In some embodiments, the nucleic acid comprises a
polynucleotide encoding a polypeptide comprising an immunoglobulin
light chain or a fragment thereof comprising a VL comprising CDRs
1, 2, and 3 comprising the amino acid sequences set forth in SEQ ID
NOs: 10, 11, and 12, respectively.
[0026] In some embodiments, the nucleic acid comprises a
polynucleotide encoding a polypeptide comprising an immunoglobulin
heavy chain or a fragment thereof comprising a VH comprising CDRs
1, 2, and 3 comprising the amino acid sequences set forth in SEQ ID
NOs: 7, 13, and 14, respectively.
[0027] In some embodiments, the nucleic acid comprises a
polynucleotide encoding a polypeptide comprising an immunoglobulin
light chain or a fragment thereof comprising a VL comprising CDRs
1, 2, and 3 comprising the amino acid sequences set forth in SEQ ID
NOs: 10, 11, and 15, respectively.
[0028] In some embodiments, the VH when paired with a VL
specifically binds to human PD-1, or the VL when paired with a VH
specifically binds to human PD-1.
[0029] In some embodiments, the immunoglobulin heavy chain or the
fragment thereof is a humanized immunoglobulin heavy chain or a
fragment thereof, and the immunoglobulin light chain or the
fragment thereof is a humanized immunoglobulin light chain or a
fragment thereof.
[0030] In some embodiments, the nucleic acid encodes a single-chain
variable fragment (scFv). In some embodiments, the nucleic acid is
cDNA.
[0031] In one aspect, the disclosure relates to a vector comprising
one or more of the nucleic acids as described herein. In some
embodiments, the vector encodes the VL region and the VH region
that together bind to PD-1.
[0032] In one aspect, the disclosure provides a pair of vectors,
wherein each vector comprises one of the nucleic acids as described
herein, wherein together the pair of vectors encodes the VL region
and the VH region that together bind to PD-1.
[0033] In another aspect, the disclosure relates to a cell
comprising the vector as described herein, or the pair of vectors
as described herein. In some embodiments, the cell is a CHO
cell.
[0034] In one aspect, the disclosure also provides a cell
comprising one or more of the nucleic acids as described
herein.
[0035] In another aspect, the disclosure provides a cell comprising
two of the nucleic acids as described herein. In some embodiments,
the two nucleic acids together encode the VL region and the VH
region that together bind to PD-1.
[0036] In another aspect, the disclosure relates to methods of
producing an antibody or an antigen-binding fragment thereof. The
methods include the steps of [0037] (a) culturing the cell as
described herein under conditions sufficient for the cell to
produce the antibody or the antigen-binding fragment; and [0038]
(b) collecting the antibody or the antigen-binding fragment
produced by the cell.
[0039] In one aspect, the disclosure relates to an antibody or
antigen-binding fragment thereof that binds to PD-1 comprising a
heavy chain variable region (VH) comprising an amino acid sequence
that is at least 90% identical to a selected VH sequence, and a
light chain variable region (VL) comprising an amino acid sequence
that is at least 90% identical to a selected VL sequence, wherein
the selected VH sequence and the selected VL sequence are one of
the following: [0040] (1) the selected VH sequence is SEQ ID NOs:
26, 27, 28, or 39, and the selected VL sequence is SEQ ID NOs: 29,
30, 31, or 40; [0041] (2) the selected VH sequence is SEQ ID NOs:
32, 33, 34, 35 or 41, and the selected VL sequence is SEQ ID NOs:
36, 37, 38 or 42; [0042] (3) the selected VH sequence is SEQ ID NO:
43, and the selected VL sequence is SEQ ID NO: 44. [0043] In some
embodiments, the VH comprises the sequence of SEQ ID NO: 26 and the
VL comprises the sequence of SEQ ID NO: 31.
[0044] In some embodiments, the VH comprises the sequence of SEQ ID
NO: 27 and the VL comprises the sequence of SEQ ID NO: 31.
[0045] In some embodiments, the antibody or antigen-binding
fragment specifically binds to human PD-1.
[0046] In some embodiments, the antibody or antigen-binding
fragment is a humanized antibody or antigen-binding fragment
thereof. In some embodiments, the antibody or antigen-binding
fragment is a single-chain variable fragment (scFV).
[0047] In one aspect, the disclosure relates to an antibody-drug
conjugate comprising the antibody or antigen-binding fragment
thereof as described herein covalently bound to a therapeutic
agent. In some embodiments, the therapeutic agent is a cytotoxic or
cytostatic agent.
[0048] In another aspect, the disclosure relates to methods of
treating a subject having cancer. The methods include the steps of
administering a therapeutically effective amount of a composition
comprising the antibody or antigen-binding fragment thereof as
described herein, or the antibody-drug conjugate as described
herein, to the subject.
[0049] In some embodiments, the subject has a solid tumor. In some
embodiments, the cancer is unresectable melanoma or metastatic
melanoma. In some embodiments, the cancer is non-small cell lung
cancer (NSCLC), squamous cell carcinoma of the head and neck
(SCCHN), head and neck cancer, renal cell carcinoma (RCC),
melanoma, bladder cancer, gastric cancer, urothelial cancer,
Merkel-cell carcinoma, triple-negative breast cancer (TNBC), or
colorectal carcinoma.
[0050] In one aspect, the disclosure relates to methods of
decreasing the rate of tumor growth. The methods include the steps
of contacting a tumor cell with an effective amount of a
composition comprising an antibody or antigen-binding fragment
thereof as described herein, or the antibody-drug conjugate as
described herein.
[0051] In another aspect, the disclosure relates methods of killing
a tumor cell. The methods include the steps of contacting a tumor
cell with an effective amount of a composition comprising the
antibody or antigen-binding fragment thereof as described herein,
or the antibody-drug conjugate as described herein.
[0052] In one aspect, the disclosure provides a pharmaceutical
composition comprising the antibody or antigen-binding fragment
thereof as described herein, and a pharmaceutically acceptable
carrier.
[0053] In another aspect, the disclosure also provides a
pharmaceutical composition comprising the antibody drug conjugate
as described herein, and a pharmaceutically acceptable carrier.
[0054] As used herein, the term "cancer" refers to cells having the
capacity for autonomous growth. Examples of such cells include
cells having an abnormal state or condition characterized by
rapidly proliferating cell growth. The term is meant to include
cancerous growths, e.g., tumors; oncogenic processes, metastatic
tissues, and malignantly transformed cells, tissues, or organs,
irrespective of histopathologic type or stage of invasiveness. Also
included are malignancies of the various organ systems, such as
respiratory, cardiovascular, renal, reproductive, hematological,
neurological, hepatic, gastrointestinal, and endocrine systems; as
well as adenocarcinomas which include malignancies such as most
colon cancers, renal-cell carcinoma, prostate cancer and/or
testicular tumors, non-small cell carcinoma of the lung, and cancer
of the small intestine. Cancer that is "naturally arising" includes
any cancer that is not experimentally induced by implantation of
cancer cells into a subject, and includes, for example,
spontaneously arising cancer, cancer caused by exposure of a
patient to a carcinogen(s), cancer resulting from insertion of a
transgenic oncogene or knockout of a tumor suppressor gene, and
cancer caused by infections, e.g., viral infections. The term
"carcinoma" is art recognized and refers to malignancies of
epithelial or endocrine tissues. The term also includes
carcinosarcomas, which include malignant tumors composed of
carcinomatous and sarcomatous tissues. An "adenocarcinoma" refers
to a carcinoma derived from glandular tissue or in which the tumor
cells form recognizable glandular structures. The term "sarcoma" is
art recognized and refers to malignant tumors of mesenchymal
derivation. The term "hematopoietic neoplastic disorders" includes
diseases involving hyperplastic/neoplastic cells of hematopoietic
origin. A hematopoietic neoplastic disorder can arise from myeloid,
lymphoid or erythroid lineages, or precursor cells thereof.
[0055] As used herein, the term "antibody" refers to any
antigen-binding molecule that contains at least one (e.g., one,
two, three, four, five, or six) complementary determining region
(CDR) (e.g., any of the three CDRs from an immunoglobulin light
chain or any of the three CDRs from an immunoglobulin heavy chain)
and is capable of specifically binding to an epitope. Non-limiting
examples of antibodies include: monoclonal antibodies, polyclonal
antibodies, multi-specific antibodies (e.g., bi-specific
antibodies), single-chain antibodies, chimeric antibodies, human
antibodies, and humanized antibodies. In some embodiments, an
antibody can contain an Fc region of a human antibody. The term
antibody also includes derivatives, e.g., bi-specific antibodies,
single-chain antibodies, diabodies, linear antibodies, and
multi-specific antibodies formed from antibody fragments.
[0056] As used herein, the term "antigen-binding fragment" refers
to a portion of a full-length antibody, wherein the portion of the
antibody is capable of specifically binding to an antigen. In some
embodiments, the antigen-binding fragment contains at least one
variable domain (e.g., a variable domain of a heavy chain or a
variable domain of light chain). Non-limiting examples of antibody
fragments include, e.g., Fab, Fab', F(ab').sub.2, and Fv
fragments.
[0057] As used herein, the term "human antibody" refers to an
antibody that is encoded by an endogenous nucleic acid (e.g.,
rearranged human immunoglobulin heavy or light chain locus) present
in a human. In some embodiments, a human antibody is collected from
a human or produced in a human cell culture (e.g., human hybridoma
cells). In some embodiments, a human antibody is produced in a
non-human cell (e.g., a mouse or hamster cell line). In some
embodiments, a human antibody is produced in a bacterial or yeast
cell. In some embodiments, a human antibody is produced in a
transgenic non-human animal (e.g., a bovine) containing an
unrearranged or rearranged human immunoglobulin locus (e.g., heavy
or light chain human immunoglobulin locus).
[0058] As used herein, the term "chimeric antibody" refers to an
antibody that contains a sequence present in at least two different
antibodies (e.g., antibodies from two different mammalian species
such as a human and a mouse antibody). A non-limiting example of a
chimeric antibody is an antibody containing the variable domain
sequences (e.g., all or part of a light chain and/or heavy chain
variable domain sequence) of a non-human (e.g., mouse) antibody and
the constant domains of a human antibody. Additional examples of
chimeric antibodies are described herein and are known in the
art.
[0059] As used herein, the term "humanized antibody" refers to a
non-human antibody which contains minimal sequence derived from a
non-human (e.g., mouse) immunoglobulin and contains sequences
derived from a human immunoglobulin. In non-limiting examples,
humanized antibodies are human antibodies (recipient antibody) in
which hypervariable (e.g., CDR) region residues of the recipient
antibody are replaced by hypervariable (e.g., CDR) region residues
from a non-human antibody (e.g., a donor antibody), e.g., a mouse,
rat, or rabbit antibody, having the desired specificity, affinity,
and capacity. In some embodiments, the Fv framework residues of the
human immunoglobulin are replaced by corresponding non-human (e.g.,
mouse) immunoglobulin residues. In some embodiments, humanized
antibodies may contain residues which are not found in the
recipient antibody or in the donor antibody. These modifications
can be made to further refine antibody performance. In some
embodiments, the humanized antibody contains substantially all of
at least one, and typically two, variable domains, in which all or
substantially all of the hypervariable loops (CDRs) correspond to
those of a non-human (e.g., mouse) immunoglobulin and all or
substantially all of the framework regions are those of a human
immunoglobulin. The humanized antibody can also contain at least a
portion of an immunoglobulin constant region (Fc), typically, that
of a human immunoglobulin. Humanized antibodies can be produced
using molecular biology methods known in the art. Non-limiting
examples of methods for generating humanized antibodies are
described herein.
[0060] As used herein, the term "single-chain antibody" refers to a
single polypeptide that contains at least two immunoglobulin
variable domains (e.g., a variable domain of a mammalian
immunoglobulin heavy chain or light chain) that is capable of
specifically binding to an antigen. Non-limiting examples of
single-chain antibodies are described herein.
[0061] As used herein, the term "multimeric antibody" refers to an
antibody that contains four or more (e.g., six, eight, or ten)
immunoglobulin variable domains. In some embodiments, the
multimeric antibody is able to crosslink one target molecule (e.g.,
PD-1) to at least one second target molecule (e.g., CTLA-4) on the
surface of a mammalian cell (e.g., a human T-cell).
[0062] As used herein, the terms "subject" and "patient" are used
interchangeably throughout the specification and describe an
animal, human or non-human, to whom treatment according to the
methods of the present invention is provided. Veterinary and
non-veterinary applications are contemplated by the present
invention. Human patients can be adult humans or juvenile humans
(e.g., humans below the age of 18 years old). In addition to
humans, patients include but are not limited to mice, rats,
hamsters, guinea-pigs, rabbits, ferrets, cats, dogs, and primates.
Included are, for example, non-human primates (e.g., monkey,
chimpanzee, gorilla, and the like), rodents (e.g., rats, mice,
gerbils, hamsters, ferrets, rabbits), lagomorphs, swine (e.g., pig,
miniature pig), equine, canine, feline, bovine, and other domestic,
farm, and zoo animals.
[0063] As used herein, when referring to an antibody, the phrases
"specifically binding" and "specifically binds" mean that the
antibody interacts with its target molecule (e.g., PD-1) preferably
to other molecules, because the interaction is dependent upon the
presence of a particular structure (i.e., the antigenic determinant
or epitope) on the target molecule; in other words, the reagent is
recognizing and binding to molecules that include a specific
structure rather than to all molecules in general. An antibody that
specifically binds to the target molecule may be referred to as a
target-specific antibody. For example, an antibody that
specifically binds to a PD-1 molecule may be referred to as a
PD-1-specific antibody or an anti-PD-1 antibody.
[0064] As used herein, the terms "polypeptide," "peptide," and
"protein" are used interchangeably to refer to polymers of amino
acids of any length of at least two amino acids.
[0065] As used herein, the terms "polynucleotide," "nucleic acid
molecule," and "nucleic acid sequence" are used interchangeably
herein to refer to polymers of nucleotides of any length of at
least two nucleotides, and include, without limitation, DNA, RNA,
DNA/RNA hybrids, and modifications thereof.
[0066] Unless otherwise defined, all technical and scientific terms
used herein have the same meaning as commonly understood by one of
ordinary skill in the art to which this invention belongs. Methods
and materials are described herein for use in the present
invention; other, suitable methods and materials known in the art
can also be used. The materials, methods, and examples are
illustrative only and not intended to be limiting. All
publications, patent applications, patents, sequences, database
entries, and other references mentioned herein are incorporated by
reference in their entirety. In case of conflict, the present
specification, including definitions, will control.
[0067] Other features and advantages of the invention will be
apparent from the following detailed description and figures, and
from the claims.
DESCRIPTION OF DRAWINGS
[0068] FIG. 1 is a flow chart showing the first part of an
exemplary protocol of making anti-hPD-1 antibodies.
[0069] FIG. 2 is a flow chart showing the second part of an
exemplary protocol of making anti-hPD-1 antibodies.
[0070] FIG. 3 is a set of flow cytometry graphs showing that the
anti-hPD-1 antibodies block the binding between hPD-1 and
hPD-L1.
[0071] FIG. 4 is a set of graphs showing flow cytometry results of
analyzing the anti-hPD-1 antibodies' cross-reactivity with monkey
PD-1 (rmPD-1), mouse PD-1 (mPD-1), and human-mouse chimeric PD-1
(chiPD-1). NC stands for negative control.
[0072] FIG. 5 is a graph showing the results of surface plasma
resonance (SPR) using the chimeric anti-hPD-1 antibody
1A7-mHvKv-IgG4-S228P and human PD-1.
[0073] FIG. 6 is a graph showing the results of surface plasma
resonance (SPR) using the chimeric anti-hPD-1 antibody
3F1-mHvKv-IgG4-S228P and human PD-1.
[0074] FIG. 7 is a graph showing body weight over time of humanized
PD-1 mice (B-hPD-1) with MC-38 tumor cells treated with mouse
anti-hPD-1 antibodies and Keytruda. PS stands for physiological
saline.
[0075] FIG. 8 is a graph showing percentage change of body weight
over time of humanized PD-1 mice (B-hPD-1) with MC-38 tumor cells
treated with mouse anti-hPD-1 antibodies and Keytruda. PS stands
for physiological saline.
[0076] FIG. 9 is a graph showing tumor size over time in humanized
PD-1 mice (B-hPD-1) with MC-38 tumor cells treated with mouse
anti-hPD-1 antibodies and Keytruda. PS stands for physiological
saline.
[0077] FIG. 10 is a graph showing body weight over time of
humanized PD-1 mice (B-hPD-1) with MC-38 tumor cells treated with
chimeric anti-hPD-1 antibodies and Keytruda. PS stands for
physiological saline.
[0078] FIG. 11 is a graph showing percentage change of body weight
over time of humanized PD-1 mice (B-hPD-1) with MC-38 tumor cells
treated with chimeric anti-hPD-1 antibodies and Keytruda. PS stands
for physiological saline.
[0079] FIG. 12 is a graph showing tumor size over time in humanized
PD-1 mice (B-hPD-1) with MC-38 tumor cells treated with chimeric
anti-hPD-1 antibodies and Keytruda. PS stands for physiological
saline.
[0080] FIG. 13 is a graph showing body weight over time of
humanized PD-1 mice (B-hPD-1) with MC-38 tumor cells treated with
humanized anti-hPD-1 antibodies and Keytruda. PS stands for
physiological saline.
[0081] FIG. 14 is a graph showing percentage change of body weight
over time of humanized PD-1 mice (B-hPD-1) with MC-38 tumor cells
treated with humanized anti-hPD-1 antibodies and Keytruda. PS
stands for physiological saline.
[0082] FIG. 15 is a graph showing tumor size over time in humanized
PD-1 mice (B-hPD-1) with MC-38 tumor cells treated with humanized
anti-hPD-1 antibodies and Keytruda. PS stands for physiological
saline.
[0083] FIG. 16 lists CDR sequences of mouse anti-hPD-1 antibodies
(25-1A7, 18-3F1, 3-6G1) and CDR sequences of humanized anti-hPD-1
antibodies thereof as defined by Kabat numbering.
[0084] FIG. 17 lists CDR sequences of mouse anti-hPD-1 antibodies
(25-1A7, 18-3F1, 3-6G1) and CDR sequences of humanized anti-hPD-1
antibodies thereof as defined by Chothia numbering.
[0085] FIG. 18 lists amino acid sequences of human PD-1 (hPD-1),
mouse PD-1 (mPD-1), monkey PD-1 (rmPD-1), and chimeric PD-1
(chiPD-1).
[0086] FIG. 19 lists amino acid sequences of heavy chain variable
regions and light chain variable regions of humanized anti-hPD-1
antibodies.
[0087] FIG. 20 lists the amino acid sequence of the heavy chain
variable regions and light chain variable regions of mouse
anti-hPD-1 antibodies 25-1A7, 18-3F1, and 3-6G1.
DETAILED DESCRIPTION
[0088] The present disclosure provides examples of antibodies,
antigen-binding fragment thereof, that bind to PD-1 (Programmed
Cell Death Protein 1; also known as CD279).
PD-1 and Cancer
[0089] The immune system can differentiate between normal cells in
the body and those it sees as "foreign", which allows the immune
system to attack the foreign cells while leaving the normal cells
alone. This mechanism sometimes involves proteins called immune
checkpoints. Immune checkpoints are molecules in the immune system
that either turn up a signal (co-stimulatory molecules) or turn
down a signal.
[0090] Checkpoint inhibitors can prevent the immune system from
attacking normal tissue and thereby preventing autoimmune diseases.
Many tumor cells also express checkpoint inhibitors. These tumor
cells escape immune surveillance by co-opting certain
immune-checkpoint pathways, particularly in T cells that are
specific for tumor antigens (Creelan, Benjamin C. "Update on immune
checkpoint inhibitors in lung cancer." Cancer Control 21.1 (2014):
80-89). Because many immune checkpoints are initiated by
ligand-receptor interactions, they can be readily blocked by
antibodies against the ligands and/or their receptors.
[0091] PD-1 (programmed death-1) is an immune checkpoint and guards
against autoimmunity through a dual mechanism of promoting
apoptosis (programmed cell death) in antigen-specific T-cells in
lymph nodes while simultaneously reducing apoptosis in regulatory T
cells (anti-inflammatory, suppressive T cells).
[0092] PD-1 is mainly expressed on the surfaces of T cells and
primary B cells; two ligands of PD-1 (PD-L1 and PD-L2) are widely
expressed in antigen-presenting cells (APCs). The interaction of
PD-1 with its ligands plays an important role in the negative
regulation of the immune response. Inhibition the binding between
PD-1 and its ligand can make the tumor cells exposed to the killing
effect of the immune system, and thus can reach the effect of
killing tumor tissues and treating cancers.
[0093] PD-L1 is expressed on the neoplastic cells of many different
cancers. By binding to PD-1 on T-cells leading to its inhibition,
PD-L1 expression is a major mechanism by which tumor cells can
evade immune attack. PD-L1 over-expression may conceptually be due
to 2 mechanisms, intrinsic and adaptive. Intrinsic expression of
PD-L1 on cancer cells is related to cellular/genetic aberrations in
these neoplastic cells. Activation of cellular signaling including
the AKT and STAT pathways results in increased PD-L1 expression. In
primary mediastinal B-cell lymphomas, gene fusion of the MHC class
II transactivator (CIITA) with PD-L1 or PD-L2 occurs, resulting in
over expression of these proteins. Amplification of chromosome
9p23-24, where PD-L1 and PD-L2 are located, leads to increased
expression of both proteins in classical Hodgkin lymphoma. Adaptive
mechanisms are related to induction of PD-L1 expression in the
tumor microenvironment. PD-L1 can be induced on neoplastic cells in
response to interferon .gamma.. In microsatellite instability colon
cancer, PD-L1 is mainly expressed on myeloid cells in the tumors,
which then suppress cytotoxic T-cell function.
[0094] The use of PD-1 blockade to enhance anti-tumor immunity
originated from observations in chronic infection models, where
preventing PD-1 interactions reversed T-cell exhaustion. Similarly,
blockade of PD-1 prevents T-cell PD-1/tumor cell PD-L1 or T-cell
PD-1/tumor cell PD-L2 interaction, leading to restoration of T-cell
mediated anti-tumor immunity.
[0095] A detailed description of PD-1, and the use of anti-PD-1
antibodies to treat cancers are described, e.g., in Topalian,
Suzanne L., et al. "Safety, activity, and immune correlates of
anti-PD-1 antibody in cancer." New England Journal of Medicine
366.26 (2012): 2443-2454; Hirano, Fumiya, et al. "Blockade of B7-H1
and PD-1 by monoclonal antibodies potentiates cancer therapeutic
immunity." Cancer research 65.3 (2005): 1089-1096; Raedler, Lisa A.
"Keytruda (pembrolizumab): first PD-1 inhibitor approved for
previously treated unresectable or metastatic melanoma." American
health & drug benefits 8.Spec Feature (2015): 96; Kwok, Gerry,
et al. "Pembrolizumab (Keytruda)." (2016): 2777-2789; US
20170247454; U.S. Pat. Nos. 9,834,606 B; and 8,728,474; each of
which is incorporated by reference in its entirety.
[0096] The present disclosure provides several anti-PD-1
antibodies, antigen-binding fragments thereof, and methods of using
these anti-PD-1 antibodies and antigen-binding fragments to inhibit
tumor growth and to treat cancers.
Antibodies and Antigen Binding Fragments
[0097] The present disclosure provides anti-PD-1 antibodies and
antigen-binding fragments thereof. In general, antibodies (also
called immunoglobulins) are made up of two classes of polypeptide
chains, light chains and heavy chains. A non-limiting antibody of
the present disclosure can be an intact, four immunoglobulin chain
antibody comprising two heavy chains and two light chains. The
heavy chain of the antibody can be of any isotype including IgM,
IgG, IgE, IgA, or IgD or sub-isotype including IgG1, IgG2, IgG2a,
IgG2b, IgG3, IgG4, IgE1, IgE2, etc. The light chain can be a kappa
light chain or a lambda light chain. An antibody can comprise two
identical copies of a light chain and two identical copies of a
heavy chain. The heavy chains, which each contain one variable
domain (or variable region, V.sub.H) and multiple constant domains
(or constant regions), bind to one another via disulfide bonding
within their constant domains to form the "stem" of the antibody.
The light chains, which each contain one variable domain (or
variable region, V.sub.L) and one constant domain (or constant
region), each bind to one heavy chain via disulfide binding. The
variable region of each light chain is aligned with the variable
region of the heavy chain to which it is bound. The variable
regions of both the light chains and heavy chains contain three
hypervariable regions sandwiched between more conserved framework
regions (FR).
[0098] These hypervariable regions, known as the complementary
determining regions (CDRs), form loops that comprise the principle
antigen binding surface of the antibody. The four framework regions
largely adopt a beta-sheet conformation and the CDRs form loops
connecting, and in some cases forming part of, the beta-sheet
structure. The CDRs in each chain are held in close proximity by
the framework regions and, with the CDRs from the other chain,
contribute to the formation of the antigen-binding region.
[0099] Methods for identifying the CDR regions of an antibody by
analyzing the amino acid sequence of the antibody are well known,
and a number of definitions of the CDRs are commonly used. The
Kabat definition is based on sequence variability, and the Chothia
definition is based on the location of the structural loop regions.
These methods and definitions are described in, e.g., Martin,
"Protein sequence and structure analysis of antibody variable
domains," Antibody engineering, Springer Berlin Heidelberg, 2001.
422-439; Abhinandan, et al. "Analysis and improvements to Kabat and
structurally correct numbering of antibody variable domains,"
Molecular immunology 45.14 (2008): 3832-3839; Wu, T. T. and Kabat,
E. A. (1970) J. Exp. Med. 132: 211-250; Martin et al., Methods
Enzymol. 203:121-53 (1991); Morea et al., Biophys Chem.
68(1-3):9-16 (October 1997); Morea et al., J Mol Biol.
275(2):269-94 (January. 1998); Chothia et al., Nature
342(6252):877-83 (December 1989); Ponomarenko and Bourne, BMC
Structural Biology 7:64 (2007); each of which is incorporated
herein by reference in its entirety. Unless specifically indicated
in the present disclosure, Kabat numbering is used in the present
disclosure as a default.
[0100] The CDRs are important for recognizing an epitope of an
antigen. As used herein, an "epitope" is the smallest portion of a
target molecule capable of being specifically bound by the antigen
binding domain of an antibody. The minimal size of an epitope may
be about three, four, five, six, or seven amino acids, but these
amino acids need not be in a consecutive linear sequence of the
antigen's primary structure, as the epitope may depend on an
antigen's three-dimensional configuration based on the antigen's
secondary and tertiary structure.
[0101] In some embodiments, the antibody is an intact
immunoglobulin molecule (e.g., IgG1, IgG2a, IgG2b, IgG3, IgM, IgD,
IgE, IgA). The IgG subclasses (IgG1, IgG2, IgG3, and IgG4) are
highly conserved, differ in their constant region, particularly in
their hinges and upper CH2 domains. The sequences and differences
of the IgG subclasses are known in the art, and are described,
e.g., in Vidarsson, et al, "IgG subclasses and allotypes: from
structure to effector functions." Frontiers in immunology 5 (2014);
Irani, et al. "Molecular properties of human IgG subclasses and
their implications for designing therapeutic monoclonal antibodies
against infectious diseases." Molecular immunology 67.2 (2015):
171-182; Shakib, Farouk, ed. The human IgG subclasses: molecular
analysis of structure, function and regulation. Elsevier, 2016;
each of which is incorporated herein by reference in its
entirety.
[0102] The antibody can also be an immunoglobulin molecule that is
derived from any species (e.g., human, rodent, mouse, camelid).
Antibodies disclosed herein also include, but are not limited to,
polyclonal, monoclonal, monospecific, polyspecific antibodies, and
chimeric antibodies that include an immunoglobulin binding domain
fused to another polypeptide. The term "antigen binding domain" or
"antigen binding fragment" is a portion of an antibody that retains
specific binding activity of the intact antibody, i.e., any portion
of an antibody that is capable of specific binding to an epitope on
the intact antibody's target molecule. It includes, e.g., Fab,
Fab', F(ab').sub.2, and variants of these fragments. Thus, in some
embodiments, an antibody or an antigen binding fragment thereof can
be, e.g., a scFv, a Fv, a Fd, a dAb, a bispecific antibody, a
bispecific scFv, a diabody, a linear antibody, a single-chain
antibody molecule, a multi-specific antibody formed from antibody
fragments, and any polypeptide that includes a binding domain which
is, or is homologous to, an antibody binding domain. Non-limiting
examples of antigen binding domains include, e.g., the heavy chain
and/or light chain CDRs of an intact antibody, the heavy and/or
light chain variable regions of an intact antibody, full length
heavy or light chains of an intact antibody, or an individual CDR
from either the heavy chain or the light chain of an intact
antibody.
[0103] In some embodiments, the antigen binding fragment can form a
part of a chimeric antigen receptor (CAR). In some embodiments, the
chimeric antigen receptor are fusions of single-chain variable
fragments (scFv) as described herein, fused to CD3-zeta
transmembrane- and endodomain. In some embodiments, the chimeric
antigen receptor also comprises intracellular signaling domains
from various costimulatory protein receptors (e.g., CD28, 41BB,
ICOS). In some embodiments, the chimeric antigen receptor comprises
multiple signaling domains, e.g., CD3z-CD28-41BB or CD3z-CD28-OX40,
to increase potency. Thus, in one aspect, the disclosure further
provides cells (e.g., T cells) that express the chimeric antigen
receptors as described herein.
[0104] In some embodiments, the scFV has one heavy chain variable
domain, and one light chain variable domain.
Anti-PD-1 Antibodies and Antigen-Binding Fragments
[0105] The disclosure provides antibodies and antigen-binding
fragments thereof that specifically bind to PD-1. The antibodies
and antigen-binding fragments described herein are capable of
binding to PD-1 and can promote PD-1 signaling pathway thus
increase immune response. The disclosure provides e.g., mouse
anti-PD-1 antibodies 25-1A7 ("1A7"), 18-3F1 ("3F1"), and 3-6G1
("6G1"), the chimeric antibodies thereof, and the humanized
antibodies thereof (e.g., antibodies as shown in Table 2).
[0106] The CDR sequences for 1A7, and 1A7 derived antibodies (e.g.,
humanized antibodies) include CDRs of the heavy chain variable
domain, SEQ ID NOs: 1-3, and CDRs of the light chain variable
domain, SEQ ID NOs: 4-6 as defined by Kabat numbering. The CDRs can
also be defined by Chothia system. Under the Chothia numbering, the
CDR sequences of the heavy chain variable domain are set forth in
SEQ ID NOs: 16, 17, 3 and CDR sequences of the light chain variable
domain are set forth in SEQ ID NOs: 4-6.
[0107] Similarly, the CDR sequences for 3F1, and 3F1 derived
antibodies include CDRs of the heavy chain variable domain, SEQ ID
NOs: 7-9, and CDRs of the light chain variable domain, SEQ ID NOs:
10-12, as defined by Kabat numbering. Under Chothia numbering, the
CDR sequences of the heavy chain variable domain are set forth in
SEQ ID NOs: 18, 19, 9, and CDRs of the light chain variable domain
are set forth in SEQ ID NOs: 10-12.
[0108] The CDR sequences for 6G1, and 6G1 derived antibodies
include CDRs of the heavy chain variable domain, SEQ ID NOs: 7, 13,
14, and CDRs of the light chain variable domain, SEQ ID NOs: 10,
11, 15, as defined by Kabat numbering. Under Chothia numbering, the
CDR sequences of the heavy chain variable domain are set forth in
SEQ ID NOs: 20, 21, 14, and CDRs of the light chain variable domain
are set forth in SEQ ID NOs: 10, 11, 15.
[0109] The amino acid sequences for heavy chain variable regions
and light variable regions of the humanized antibodies are also
provided. As there are different ways to humanize a mouse antibody
(e.g., a sequence can be modified with different amino acid
substitutions), the heavy chain and the light chain of an antibody
can have more than one version of humanized sequences. The amino
acid sequences for the heavy chain variable regions of humanized
1A7 antibody are set forth in SEQ ID NOs: 26-28. The amino acid
sequences for the light chain variable regions of humanized 1A7
antibody are set forth in SEQ ID NOs: 29-31. Any of these heavy
chain variable region sequences (SEQ ID NO: 26-28) can be paired
with any of these light chain variable region sequences (SEQ ID NO:
29-31).
[0110] Similarly, the amino acid sequences for the heavy chain
variable region of humanized 3F1 antibody are set forth in SEQ ID
NOs: 32-35. The amino acid sequences for the light chain variable
region of humanized 3F1 antibody are set forth in SEQ ID NOs:
36-38. Any of these heavy chain variable region sequences (SEQ ID
NO: 32-35) can be paired with any of these light chain variable
region sequences (SEQ ID NO: 36-38).
[0111] As shown in FIG. 19, humanization percentage means the
percentage identity of the heavy chain or light chain variable
region sequence as compared to human antibody sequences in
International Immunogenetics Information System (IMGT) database.
The top hit means that the heavy chain or light chain variable
region sequence is closer to a particular species than to other
species. For example, top hit to human means that the sequence is
closer to human than to other species. Top hit to human and Macaca
fascicularis means that the sequence has the same percentage
identity to the human sequence and the Macaca fascicularis
sequence, and these percentages identities are highest as compared
to the sequences of other species. In some embodiments,
humanization percentage is greater than 80%, 81%, 82%, 83%, 84%,
85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, or 95%. A
detailed description regarding how to determine humanization
percentage and how to determine top hits is known in the art, and
is described, e.g., in Jones, Tim D., et al. "The INNs and outs of
antibody nonproprietary names." MAbs. Vol. 8. No. 1. Taylor &
Francis, 2016, which is incorporated herein by reference in its
entirety. A high humanization percentage often has various
advantages, e.g., more safe and more effective in humans, more
likely to be tolerated by a human subject, and/or less likely to
have side effects.
[0112] Furthermore, in some embodiments, the antibodies or
antigen-binding fragments thereof described herein can also contain
one, two, or three heavy chain variable region CDRs selected from
the group of SEQ ID NOs: 1-3, SEQ ID NOs: 7-9, SEQ ID NOs: 7, 13,
14, SEQ ID NOs: 16, 17, 3, SEQ ID NOs: 18, 19, 9, and SEQ ID NOs:
20, 21, 14; and/or one, two, or three light chain variable region
CDRs selected from the group of SEQ ID NOs: 4-6, SEQ ID NOs 10-12,
and SEQ ID NOs: 10, 11, 15.
[0113] In some embodiments, the antibodies can have a heavy chain
variable region (VH) comprising complementarity determining regions
(CDRs) 1, 2, 3, wherein the CDR1 region comprises or consists of an
amino acid sequence that is at least 80%, 85%, 90%, or 95%
identical to a selected VH CDR1 amino acid sequence, the CDR2
region comprises or consists of an amino acid sequence that is at
least 80%, 85%, 90%, or 95% identical to a selected VH CDR2 amino
acid sequence, and the CDR3 region comprises or consists of an
amino acid sequence that is at least 80%, 85%, 90%, or 95%
identical to a selected VH CDR3 amino acid sequence, and a light
chain variable region (VL) comprising CDRs 1, 2, 3, wherein the
CDR1 region comprises or consists of an amino acid sequence that is
at least 80%, 85%, 90%, or 95% identical to a selected VL CDR1
amino acid sequence, the CDR2 region comprises or consists of an
amino acid sequence that is at least 80%, 85%, 90%, or 95%
identical to a selected VL CDR2 amino acid sequence, and the CDR3
region comprises or consists of an amino acid sequence that is at
least 80%, 85%, 90%, or 95% identical to a selected VL CDR3 amino
acid sequence. The selected VH CDRs 1, 2, 3 amino acid sequences
and the selected VL CDRs, 1, 2, 3 amino acid sequences are shown in
FIG. 16(Kabat CDR) and FIG. 17 (Chothia CDR).
[0114] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a heavy chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 1 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 2 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 3 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0115] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a heavy chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 7 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 8 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 9 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0116] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a heavy chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 7 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 13 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 14 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0117] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a heavy chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 16 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 17 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 3 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0118] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a heavy chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 18 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 19 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 9 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0119] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a heavy chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 20 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 21 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 14 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0120] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a light chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 4 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 5 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 6 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0121] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a light chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 10 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 11 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 12 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0122] In some embodiments, the antibody or an antigen-binding
fragment described herein can contain a light chain variable domain
containing one, two, or three of the CDRs of SEQ ID NO: 10 with
zero, one or two amino acid insertions, deletions, or
substitutions; SEQ ID NO: 11 with zero, one or two amino acid
insertions, deletions, or substitutions; SEQ ID NO: 15 with zero,
one or two amino acid insertions, deletions, or substitutions.
[0123] The insertions, deletions, and substitutions can be within
the CDR sequence, or at one or both terminal ends of the CDR
sequence.
[0124] The disclosure also provides antibodies or antigen-binding
fragments thereof that bind to PD-1. The antibodies or
antigen-binding fragments thereof contain a heavy chain variable
region (VH) comprising or consisting of an amino acid sequence that
is at least 80%, 85%, 90%, or 95% identical to a selected VH
sequence, and a light chain variable region (VL) comprising or
consisting of an amino acid sequence that is at least 80%, 85%,
90%, or 95% identical to a selected VL sequence. In some
embodiments, the selected VH sequence is SEQ ID NOs: 26, 27, 28, or
39, and the selected VL sequence is SEQ ID NOs: 29, 30, 31, or 40.
In some embodiments, the selected VH sequence is SEQ ID NOs: 32,
33, 34, 35, or 41 and the selected VL sequence is SEQ ID NOs: 36,
37, 38, or 42. In some embodiments, the selected VH sequence is SEQ
ID NO: 43, and the selected VL sequence is SEQ ID NO: 44.
[0125] To determine the percent identity of two amino acid
sequences, or of two nucleic acid sequences, the sequences are
aligned for optimal comparison purposes (e.g., gaps can be
introduced in one or both of a first and a second amino acid or
nucleic acid sequence for optimal alignment and non-homologous
sequences can be disregarded for comparison purposes). The length
of a reference sequence aligned for comparison purposes is at least
80% of the length of the reference sequence, and in some
embodiments is at least 90%, 95%, or 100%. The amino acid residues
or nucleotides at corresponding amino acid positions or nucleotide
positions are then compared. When a position in the first sequence
is occupied by the same amino acid residue or nucleotide as the
corresponding position in the second sequence, then the molecules
are identical at that position. The percent identity between the
two sequences is a function of the number of identical positions
shared by the sequences, taking into account the number of gaps,
and the length of each gap, which need to be introduced for optimal
alignment of the two sequences. For purposes of the present
disclosure, the comparison of sequences and determination of
percent identity between two sequences can be accomplished using a
Blossum 62 scoring matrix with a gap penalty of 12, a gap extend
penalty of 4, and a frameshift gap penalty of 5.
[0126] The disclosure also provides nucleic acid comprising a
polynucleotide encoding a polypeptide comprising an immunoglobulin
heavy chain or an immunoglobulin light chain. The immunoglobulin
heavy chain or immunoglobulin light chain comprises CDRs as shown
in FIG. 16 or FIG. 17, or have sequences as shown in FIG. 19 or
FIG. 20. When the polypeptides are paired with corresponding
polypeptide (e.g., a corresponding heavy chain variable region or a
corresponding light chain variable region), the paired polypeptides
bind to PD-1 (e.g., human PD-1).
[0127] The anti-PD-1 antibodies and antigen-binding fragments can
also be antibody variants (including derivatives and conjugates) of
antibodies or antibody fragments and multi-specific (e.g.,
bi-specific) antibodies or antibody fragments. Additional
antibodies provided herein are polyclonal, monoclonal,
multi-specific (multimeric, e.g., bi-specific), human antibodies,
chimeric antibodies (e.g., human-mouse chimera), single-chain
antibodies, intracellularly-made antibodies (i.e., intrabodies),
and antigen-binding fragments thereof. The antibodies or
antigen-binding fragments thereof can be of any type (e.g., IgG,
IgE, IgM, IgD, IgA, and IgY), class (e.g., IgG1, IgG2, IgG3, IgG4,
IgA1, and IgA2), or subclass. In some embodiments, the antibody or
antigen-binding fragment thereof is an IgG antibody or
antigen-binding fragment thereof.
[0128] Fragments of antibodies are suitable for use in the methods
provided so long as they retain the desired affinity and
specificity of the full-length antibody. Thus, a fragment of an
antibody that binds to PD-1 will retain an ability to bind to PD-1.
An Fv fragment is an antibody fragment which contains a complete
antigen recognition and binding site. This region consists of a
dimer of one heavy and one light chain variable domain in tight
association, which can be covalent in nature, for example in scFv.
It is in this configuration that the three CDRs of each variable
domain interact to define an antigen binding site on the surface of
the VH-VL dimer. Collectively, the six CDRs or a subset thereof
confer antigen binding specificity to the antibody. However, even a
single variable domain (or half of an Fv comprising only three CDRs
specific for an antigen) can have the ability to recognize and bind
antigen, although usually at a lower affinity than the entire
binding site.
[0129] Single-chain Fv or (scFv) antibody fragments comprise the VH
and VL domains (or regions) of antibody, wherein these domains are
present in a single polypeptide chain. Generally, the scFv
polypeptide further comprises a polypeptide linker between the VH
and VL domains, which enables the scFv to form the desired
structure for antigen binding.
[0130] The Fab fragment contains a variable and constant domain of
the light chain and a variable domain and the first constant domain
(CH1) of the heavy chain. F(ab').sub.2 antibody fragments comprise
a pair of Fab fragments which are generally covalently linked near
their carboxy termini by hinge cysteines between them. Other
chemical couplings of antibody fragments are also known in the
art.
[0131] Diabodies are small antibody fragments with two
antigen-binding sites, which fragments comprise a VH connected to a
VL in the same polypeptide chain (VH and VL). By using a linker
that is too short to allow pairing between the two domains on the
same chain, the domains are forced to pair with the complementary
domains of another chain and create two antigen-binding sites.
[0132] Linear antibodies comprise a pair of tandem Fd segments
(VH--CH1-VH--CH1) which, together with complementary light chain
polypeptides, form a pair of antigen binding regions. Linear
antibodies can be bispecific or monospecific.
[0133] Antibodies and antibody fragments of the present disclosure
can be modified in the Fc region to provide desired effector
functions or serum half-life.
[0134] Multimerization of antibodies may be accomplished through
natural aggregation of antibodies or through chemical or
recombinant linking techniques known in the art. For example, some
percentage of purified antibody preparations (e.g., purified
IgG.sub.1 molecules) spontaneously form protein aggregates
containing antibody homodimers and other higher-order antibody
multimers.
[0135] Alternatively, antibody homodimers may be formed through
chemical linkage techniques known in the art. For example,
heterobifunctional crosslinking agents including, but not limited
to SMCC (succinimidyl 4-(maleimidomethyl)cyclohexane-1-carboxylate)
and SATA (N-succinimidyl S-acetylthio-acetate) can be used to form
antibody multimers. An exemplary protocol for the formation of
antibody homodimers is described in Ghetie et al. (Proc. Natl.
Acad. Sci. U.S.A. 94: 7509-7514, 1997). Antibody homodimers can be
converted to Fab'.sub.2 homodimers through digestion with pepsin.
Another way to form antibody homodimers is through the use of the
autophilic T15 peptide described in Zhao et al. (J. Immunol.
25:396-404, 2002).
[0136] In some embodiments, the multi-specific antibody is a
bi-specific antibody. Bi-specific antibodies can be made by
engineering the interface between a pair of antibody molecules to
maximize the percentage of heterodimers that are recovered from
recombinant cell culture. For example, the interface can contain at
least a part of the CH3 domain of an antibody constant domain. In
this method, one or more small amino acid side chains from the
interface of the first antibody molecule are replaced with larger
side chains (e.g., tyrosine or tryptophan). Compensatory "cavities"
of identical or similar size to the large side chain(s) are created
on the interface of the second antibody molecule by replacing large
amino acid side chains with smaller ones (e.g., alanine or
threonine). This provides a mechanism for increasing the yield of
the heterodimer over other unwanted end-products such as
homodimers. This method is described, e.g., in WO 96/27011, which
is incorporated by reference in its entirety.
[0137] Bi-specific antibodies include cross-linked or
"heteroconjugate" antibodies. For example, one of the antibodies in
the heteroconjugate can be coupled to avidin and the other to
biotin. Heteroconjugate antibodies can also be made using any
convenient cross-linking methods. Suitable cross-linking agents and
cross-linking techniques are well known in the art and are
disclosed in U.S. Pat. No. 4,676,980, which is incorporated herein
by reference in its entirety.
[0138] Methods for generating bi-specific antibodies from antibody
fragments are also known in the art. For example, bi-specific
antibodies can be prepared using chemical linkage. Brennan et al.
(Science 229:81, 1985) describes a procedure where intact
antibodies are proteolytically cleaved to generate F(ab')2
fragments. These fragments are reduced in the presence of the
dithiol complexing agent sodium arsenite to stabilize vicinal
dithiols and prevent intermolecular disulfide formation. The Fab'
fragments generated are then converted to thionitrobenzoate (TNB)
derivatives. One of the Fab' TNB derivatives is then reconverted to
the Fab' thiol by reduction with mercaptoethylamine, and is mixed
with an equimolar amount of another Fab' TNB derivative to form the
bi-specific antibody.
[0139] Any of the antibodies or antigen-binding fragments described
herein may be conjugated to a stabilizing molecule (e.g., a
molecule that increases the half-life of the antibody or
antigen-binding fragment thereof in a subject or in solution).
Non-limiting examples of stabilizing molecules include: a polymer
(e.g., a polyethylene glycol) or a protein (e.g., serum albumin,
such as human serum albumin). The conjugation of a stabilizing
molecule can increase the half-life or extend the biological
activity of an antibody or an antigen-binding fragment in vitro
(e.g., in tissue culture or when stored as a pharmaceutical
composition) or in vivo (e.g., in a human).
[0140] In some embodiments, the antibodies or antigen-binding
fragments described herein can be conjugated to a therapeutic
agent. The antibody-drug conjugate comprising the antibody or
antigen-binding fragment thereof can covalently or non-covalently
bind to a therapeutic agent. In some embodiments, the therapeutic
agent is a cytotoxic or cytostatic agent (e.g., cytochalasin B,
gramicidin D, ethidium bromide, emetine, mitomycin, etoposide,
tenoposide, vincristine, vinblastine, colchicin, doxorubicin,
daunorubicin, dihydroxy anthracin, maytansinoids such as DM-1 and
DM-4, dione, mitoxantrone, mithramycin, actinomycin D,
1-dehydrotestosterone, glucocorticoids, procaine, tetracaine,
lidocaine, propranolol, puromycin, epirubicin, and cyclophosphamide
and analogs).
Antibody Characteristics
[0141] The antibodies or antigen-binding fragments thereof
described herein can block the binding between PD-1 and PD-L1
and/or the binding between PD-1 and PD-L2. In some embodiments, by
binding to PD-1, the antibody can inhibitPD-1 signaling pathway and
upregulates the immune response. Thus, in some embodiments, the
antibodies or antigen-binding fragments thereof as described herein
are PD-1 antagonist. In some embodiments, the antibodies or
antigen-binding fragments thereof are PD-1 agonist.
[0142] In some embodiments, the antibodies or antigen-binding
fragments thereof as described herein can increase immune response,
activity or number of T cells (e.g., CD8+ and/or CD4+ cells) by at
least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, 2 folds, 3
folds, 5 folds, 10 folds, or 20 folds. In some embodiments, the
antibodies or antigen-binding fragments thereof as described herein
can decrease the activity or number of T cells by at least 10%,
20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, 2 folds, 3 folds, 5
folds, 10 folds, or 20 folds.
[0143] In some implementations, the antibody (or antigen-binding
fragments thereof) specifically binds to PD-1 (e.g., human PD-1,
monkey PD-1, mouse PD-1, and/or chimeric PD-1) with a dissociation
rate (koff) of less than 0.1 s.sup.-1, less than 0.01 s.sup.-1,
less than 0.001 s.sup.-1, less than 0.0001 s.sup.-1, or less than
0.00001 s.sup.-1. In some embodiments, the dissociation rate (koff)
is greater than 0.01 s.sup.-1, greater than 0.001 s.sup.-1, greater
than 0.0001 s.sup.-1, greater than 0.00001 s.sup.-1, or greater
than 0.000001 s.sup.-1.
[0144] In some embodiments, kinetic association rates (kon) is
greater than 1.times.10.sup.2/Ms, greater than 1.times.10.sup.3/Ms,
greater than 1.times.10.sup.4/Ms, greater than 1.times.10.sup.5/Ms,
or greater than 1.times.10.sup.6/Ms. In some embodiments, kinetic
association rates (kon) is less than 1.times.10.sup.5/Ms, less than
1.times.10.sup.6/Ms, or less than 1.times.10.sup.7/Ms.
[0145] Affinities can be deduced from the quotient of the kinetic
rate constants (KD=koff/kon). In some embodiments, KD is less than
1.times.10.sup.-6M, less than 1.times.10.sup.-7M, less than
1.times.10.sup.-8M, less than 1.times.10.sup.-9M, or less than
1.times.10.sup.-10 M. In some embodiments, the KD is less than 50
nM, 30 nM, 20 nM, 15 nM, 10 nM, 9 nM, 8 nM, 7 nM, 6 nM, 5 nM, 4 nM,
3 nM, 2 nM, or 1 nM. In some embodiments, KD is greater than
1.times.10.sup.-7M, greater than 1.times.10.sup.-8M, greater than
1.times.10.sup.-9M, greater than 1.times.10.sup.-10 M, greater than
1.times.10.sup.-11M, or greater than 1.times.10.sup.-12M. In some
embodiments, the antibody binds to human PD-1 with KD less than or
equal to about 3 nM.
[0146] General techniques for measuring the affinity of an antibody
for an antigen include, e.g., ELISA, RIA, and surface plasmon
resonance (SPR). In some embodiments, the antibody binds to human
PD-1 (SEQ ID NO: 22), monkey PD-1 (e.g., rhesus macaque PD-1, SEQ
ID NO: 24), chimeric PD-1 (SEQ ID NO: 25), and/or mouse PD-1 (SEQ
ID NO: 23). In some embodiments, the antibody does not bind to
human PD-1 (SEQ ID NO: 22), monkey PD-1 (e.g., rhesus macaque PD-1,
SEQ ID NO: 24; [0147] cynomolgus PD-1), chimeric PD-1 (SEQ ID NO:
25), and/or mouse PD-1 (SEQ ID NO: 23).
[0148] In some embodiments, thermal stabilities are determined. The
antibodies or antigen binding fragments as described herein can
have a Tm greater than 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70,
71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,
88, 89, 90, 91, 92, 93, 94, or 95.degree. C.
[0149] As IgG can be described as a multi-domain protein, the
melting curve sometimes shows two transitions, with a first
denaturation temperature, Tm D1, and a second denaturation
temperature Tm D2. The presence of these two peaks often indicate
the denaturation of the Fcdomains (Tm D1) and Fabdomains (Tm D2),
respectively. When there are two peaks, Tm usually refers to Tm D2.
Thus, in some embodiments, the antibodies or antigen binding
fragments as described herein has a Tm D1 greater than 60, 61, 62,
63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, or
95.degree. C. In some embodiments, the antibodies or antigen
binding fragments as described herein has a Tm D2 greater than 60,
61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,
78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94,
or 95.degree. C.
[0150] In some embodiments, Tm, Tm D1, Tm D2 are less than 60, 61,
62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78,
79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, or
95.degree. C.
[0151] In some embodiments, the antibody has a tumor growth
inhibition percentage (TGI %) that is greater than 10%, 20%, 30%,
40%, 50%, 60%, 70%, 80%, 90%, 100%, 110%, 120%, 130%, 140%, 150%,
160%, 170%, 180%, 190%, or 200%. In some embodiments, the antibody
has a tumor growth inhibition percentage that is less than 60%,
70%, 80%, 90%, 100%, 110%, 120%, 130%, 140%, 150%, 160%, 170%,
180%, 190%, or 200%. The TGI % can be determined, e.g., at 3, 4, 5,
6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,
24, 25, 26, 27, 28, 29, or 30 days after the treatment starts, or
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months after the treatment
starts. As used herein, the tumor growth inhibition percentage (TGI
%) is calculated using the following formula:
TGI(%)=[1-(Ti-T0)/(Vi-V0)].times.100
Ti is the average tumor volume in the treatment group on day i. T0
is the average tumor volume in the treatment group on day zero. Vi
is the average tumor volume in the control group on day i. V0 is
the average tumor volume in the control group on day zero.
[0152] In some embodiments, the antibodies or antigen-binding
fragments thereof as described herein are PD-1 antagonist. In some
embodiments, the antibodies or antigen binding fragments decrease
PD-1 signal transduction in a target cell that expresses PD-1.
[0153] In some embodiments, the antibodies or antigen binding
fragments enhance CD4+ effector T cell function, for example, by
increasing CD4+ effector T cell proliferation and/or increasing
gamma interferon production by the CD4+ effector T cell (e.g., as
compared to proliferation and/or cytokine production prior to
treatment with the antibodies or antigen binding fragments). In
some embodiments, the cytokine is gamma interferon. In some
embodiments, the antibodies or antigen binding fragments increase
number of intratumoral (infiltrating) CD4+ effector T cells (e.g.,
total number of CD4+ effector T cells, or e.g., percentage of CD4+
cells in CD45+ cells), e.g., as compared to number of intratumoral
(infiltrating) CD4+ T cells prior to treatment with antibodies or
antigen binding fragments. In some embodiments, the antibodies or
antigen binding fragments increase number of intratumoral
(infiltrating) CD4+ effector T cells that express gamma interferon
(e.g., total gamma interferon expressing CD4+ cells, or e.g.,
percentage of gamma interferon expressing CD4+ cells in total CD4+
cells), e.g., as compared to number of intratumoral (infiltrating)
CD4+ T cells that express gamma interferon prior to treatment.
[0154] In some embodiments, the antibodies or antigen binding
fragments increase number of intratumoral (infiltrating) CD8+
effector T cells (e.g., total number of CD8+ effector T cells, or
e.g., percentage of CD8+ in CD45+ cells), e.g., as compared to
number of intratumoral (infiltrating) CD8+T effector cells prior to
treatment. In some embodiments, the antibodies or antigen binding
fragments increase number of intratumoral (infiltrating) CD8+
effector T cells that express gamma interferon (e.g., percentage of
CD8+ cells that express gamma interferon in total CD8+ cells),
e.g., compared to number of intratumoral (infiltrating) CD8+ T
cells that express gamma interferon prior to treatment with
anti-human PD-1 antibody.
[0155] In some embodiments, the antibodies or antigen binding
fragments enhance memory T cell function, for example by increasing
memory T cell proliferation and/or increasing cytokine (e.g., gamma
interferon) production by the memory cell.
[0156] In some embodiments, the antibodies or antigen binding
fragments inhibit Treg function, for example, by decreasing Treg
suppression of effector T cell function (e.g., effector T cell
proliferation and/or effector T cell cytokine secretion). In some
embodiments, the effector T cell is a CD4+ effector T cell. In some
embodiments, the antibodies or antigen binding fragments reduce the
number of intratumoral (infiltrating) Treg (e.g., total number of
Treg or e.g., percentage of Fox3p+ cells in CD4+ cells).
[0157] In some embodiments, the antibodies or antigen binding
fragments are depleting anti-hPD-1 antibody (e.g., depletes cells
that express human PD-1). In some embodiments, the antibodies or
antigen binding fragments deplete cells that express human PD-1 in
vitro. In some embodiments, the human PD-1 expressing cells are
CD4+ effector T cells, or Treg cells. In some embodiments,
depleting is by ADCC and/or phagocytosis.
[0158] In some embodiments, the antibodies or antigen binding
fragments have a functional Fc region. In some embodiments,
effector function of a functional Fc region is antibody-dependent
cell-mediated cytotoxicity (ADCC). In some embodiments, effector
function of a functional Fc region is phagocytosis. In some
embodiments, effector function of a functional Fc region is ADCC
and phagocytosis. In some embodiments, the Fc region is human IgG1,
human IgG2, human IgG3, or human IgG4.
[0159] In some embodiments, the antibodies or antigen binding
fragments do not induce apoptosis in PD-1-expressing cells (e.g.,
Treg).
[0160] In some embodiments, the antibodies or antigen binding
fragments do not have a functional Fc region. For example, the
antibodies or antigen binding fragments are Fab, Fab', F(ab')2, and
Fv fragments.
Methods of Making Anti-PD-1 Antibodies
[0161] An isolated fragment of human PD-1 can be used as an
immunogen to generate antibodies using standard techniques for
polyclonal and monoclonal antibody preparation. Polyclonal
antibodies can be raised in animals by multiple injections (e.g.,
subcutaneous or intraperitoneal injections) of an antigenic peptide
or protein. In some embodiments, the antigenic peptide or protein
is injected with at least one adjuvant. In some embodiments, the
antigenic peptide or protein can be conjugated to an agent that is
immunogenic in the species to be immunized. Animals can be injected
with the antigenic peptide or protein more than one time (e.g.,
twice, three times, or four times).
[0162] The full-length polypeptide or protein can be used or,
alternatively, antigenic peptide fragments thereof can be used as
immunogens. The antigenic peptide of a protein comprises at least 8
(e.g., at least 10, 15, 20, or 30) amino acid residues of the amino
acid sequence of PD-1 and encompasses an epitope of the protein
such that an antibody raised against the peptide forms a specific
immune complex with the protein. As described above, the full
length sequence of human PD-1 is known in the art (SEQ ID NO:
22).
[0163] An immunogen typically is used to prepare antibodies by
immunizing a suitable subject (e.g., human or transgenic animal
expressing at least one human immunoglobulin locus). An appropriate
immunogenic preparation can contain, for example, a
recombinantly-expressed or a chemically-synthesized polypeptide
(e.g., a fragment of human PD-1). The preparation can further
include an adjuvant, such as Freund's complete or incomplete
adjuvant, or a similar immunostimulatory agent.
[0164] Polyclonal antibodies can be prepared as described above by
immunizing a suitable subject with a PD-1 polypeptide, or an
antigenic peptide thereof (e.g., part of PD-1) as an immunogen. The
antibody titer in the immunized subject can be monitored over time
by standard techniques, such as with an enzyme-linked immunosorbent
assay (ELISA) using the immobilized PD-1 polypeptide or peptide. If
desired, the antibody molecules can be isolated from the mammal
(e.g., from the blood) and further purified by well-known
techniques, such as protein A of protein G chromatography to obtain
the IgG fraction. At an appropriate time after immunization, e.g.,
when the specific antibody titers are highest, antibody-producing
cells can be obtained from the subject and used to prepare
monoclonal antibodies by standard techniques, such as the hybridoma
technique originally described by Kohler et al. (Nature
256:495-497, 1975), the human B cell hybridoma technique (Kozbor et
al., Immunol. Today 4:72, 1983), the EBV-hybridoma technique (Cole
et al., Monoclonal Antibodies and Cancer Therapy, Alan R. Liss,
Inc., pp. 77-96, 1985), or trioma techniques. The technology for
producing hybridomas is well known (see, generally, Current
Protocols in Immunology, 1994, Coligan et al. (Eds.), John Wiley
& Sons, Inc., New York, N.Y.). Hybridoma cells producing a
monoclonal antibody are detected by screening the hybridoma culture
supernatants for antibodies that bind the polypeptide or epitope of
interest, e.g., using a standard ELISA assay.
[0165] Variants of the antibodies or antigen-binding fragments
described herein can be prepared by introducing appropriate
nucleotide changes into the DNA encoding a human, humanized, or
chimeric antibody, or antigen-binding fragment thereof described
herein, or by peptide synthesis. Such variants include, for
example, deletions, insertions, or substitutions of residues within
the amino acids sequences that make-up the antigen-binding site of
the antibody or an antigen-binding domain. In a population of such
variants, some antibodies or antigen-binding fragments will have
increased affinity for the target protein, e.g., PD-1. Any
combination of deletions, insertions, and/or combinations can be
made to arrive at an antibody or antigen-binding fragment thereof
that has increased binding affinity for the target. The amino acid
changes introduced into the antibody or antigen-binding fragment
can also alter or introduce new post-translational modifications
into the antibody or antigen-binding fragment, such as changing
(e.g., increasing or decreasing) the number of glycosylation sites,
changing the type of glycosylation site (e.g., changing the amino
acid sequence such that a different sugar is attached by enzymes
present in a cell), or introducing new glycosylation sites.
[0166] Antibodies disclosed herein can be derived from any species
of animal, including mammals. Non-limiting examples of native
antibodies include antibodies derived from humans, primates, e.g.,
monkeys and apes, cows, pigs, horses, sheep, camelids (e.g., camels
and llamas), chicken, goats, and rodents (e.g., rats, mice,
hamsters and rabbits), including transgenic rodents genetically
engineered to produce human antibodies.
[0167] Human and humanized antibodies include antibodies having
variable and constant regions derived from (or having the same
amino acid sequence as those derived from) human germline
immunoglobulin sequences. Human antibodies may include amino acid
residues not encoded by human germline immunoglobulin sequences
(e.g., mutations introduced by random or site-specific mutagenesis
in vitro or by somatic mutation in vivo), for example in the
CDRs.
[0168] A humanized antibody, typically has a human framework (FR)
grafted with non-human CDRs. Thus, a humanized antibody has one or
more amino acid sequence introduced into it from a source which is
non-human. These non-human amino acid residues are often referred
to as "import" residues, which are typically taken from an "import"
variable domain. Humanization can be essentially performed by e.g.,
substituting rodent CDRs or CDR sequences for the corresponding
sequences of a human antibody. These methods are described in e.g.,
Jones et al., Nature, 321:522-525 (1986); Riechmann et al., Nature,
332:323-327 (1988); Verhoeyen et al., Science, 239:1534-1536
(1988); each of which is incorporated by reference herein in its
entirety. Accordingly, "humanized" antibodies are chimeric
antibodies wherein substantially less than an intact human V domain
has been substituted by the corresponding sequence from a non-human
species. In practice, humanized antibodies are typically mouse
antibodies in which some CDR residues and some FR residues are
substituted by residues from analogous sites in human
antibodies.
[0169] The choice of human VH and VL domains to be used in making
the humanized antibodies is very important for reducing
immunogenicity. According to the so-called "best-fit" method, the
sequence of the V domain of a mouse antibody is screened against
the entire library of known human-domain sequences. The human
sequence which is closest to that of the mouse is then accepted as
the human FR for the humanized antibody (Sims et al., J. Immunol.,
151:2296 (1993); Chothia et al., J. Mol. Biol., 196:901
(1987)).
[0170] It is further important that antibodies be humanized with
retention of high specificity and affinity for the antigen and
other favorable biological properties. To achieve this goal,
humanized antibodies can be prepared by a process of analysis of
the parental sequences and various conceptual humanized products
using three-dimensional models of the parental and humanized
sequences. Three-dimensional immunoglobulin models are commonly
available and are familiar to those skilled in the art. Computer
programs are available which illustrate and display probable
three-dimensional conformational structures of selected candidate
immunoglobulin sequences. Inspection of these displays permits
analysis of the likely role of the residues in the functioning of
the candidate immunoglobulin sequence, i.e., the analysis of
residues that influence the ability of the candidate immunoglobulin
to bind its antigen. In this way, FR residues can be selected and
combined from the recipient and import sequences so that the
desired antibody characteristic, such as increased affinity for the
target antigen(s), is achieved.
[0171] Ordinarily, amino acid sequence variants of the human,
humanized, or chimeric anti-PD-1 antibody will contain an amino
acid sequence having at least 75%, 80%, 85%, 90%, 95%, 96%, 97%,
98%, or 99% percent identity with a sequence present in the light
or heavy chain of the original antibody.
[0172] Identity or homology with respect to an original sequence is
usually the percentage of amino acid residues present within the
candidate sequence that are identical with a sequence present
within the human, humanized, or chimeric anti-PD-1 antibody or
fragment, after aligning the sequences and introducing gaps, if
necessary, to achieve the maximum percent sequence identity, and
not considering any conservative substitutions as part of the
sequence identity.
[0173] Additional modifications to the anti-PD-1 antibodies or
antigen-binding fragments can be made. For example, a cysteine
residue(s) can be introduced into the Fc region, thereby allowing
interchain disulfide bond formation in this region. The homodimeric
antibody thus generated may have any increased half-life in vitro
and/or in vivo. Homodimeric antibodies with increased half-life in
vitro and/or in vivo can also be prepared using heterobifunctional
cross-linkers as described, for example, in Wolff et al. (Cancer
Res. 53:2560-2565, 1993). Alternatively, an antibody can be
engineered which has dual Fc regions (see, for example, Stevenson
et al., Anti-Cancer Drug Design 3:219-230, 1989).
[0174] In some embodiments, a covalent modification can be made to
the anti-PD-1 antibody or antigen-binding fragment thereof. These
covalent modifications can be made by chemical or enzymatic
synthesis, or by enzymatic or chemical cleavage. Other types of
covalent modifications of the antibody or antibody fragment are
introduced into the molecule by reacting targeted amino acid
residues of the antibody or fragment with an organic derivatization
agent that is capable of reacting with selected side chains or the
N- or C-terminal residues.
[0175] In some embodiments, antibody variants are provided having a
carbohydrate structure that lacks fucose attached (directly or
indirectly) to an Fc region. For example, the amount of fucose in
such antibody may be from 1% to 80%, from 1% to 65%, from 5% to 65%
or from 20% to 40%. The amount of fucose is determined by
calculating the average amount of fucose within the sugar chain at
Asn297, relative to the sum of all glycostructures attached to Asn
297 (e.g. complex, hybrid and high mannose structures) as measured
by MALDI-TOF mass spectrometry, as described in WO 2008/077546, for
example. Asn297 refers to the asparagine residue located at about
position 297 in the Fc region (Eu numbering of Fc region residues;
or position 314 in Kabat numbering); however, Asn297 may also be
located about .+-.3 amino acids upstream or downstream of position
297, i.e., between positions 294 and 300, due to minor sequence
variations in antibodies. Such fucosylation variants may have
improved ADCC function. In some embodiments, to reduce glycan
heterogeneity, the Fc region of the antibody can be further
engineered to replace the Asparagine at position 297 with Alanine
(N297A).
[0176] In some embodiments, to facilitate production efficiency by
avoiding Fab-arm exchange, the Fc region of the antibodies was
further engineered to replace the serine at position 228 (EU
numbering) of IgG4 with proline (S228P). A detailed description
regarding 5228 mutation is described, e.g., in Silva et al. "The
S228P mutation prevents in vivo and in vitro IgG4 Fab-arm exchange
as demonstrated using a combination of novel quantitative
immunoassays and physiological matrix preparation." Journal of
Biological Chemistry 290.9 (2015): 5462-5469, which is incorporated
by reference in its entirety.
Recombinant Vectors
[0177] The present disclosure also provides recombinant vectors
(e.g., an expression vectors) that include an isolated
polynucleotide disclosed herein (e.g., a polynucleotide that
encodes a polypeptide disclosed herein), host cells into which are
introduced the recombinant vectors (i.e., such that the host cells
contain the polynucleotide and/or a vector comprising the
polynucleotide), and the production of recombinant antibody
polypeptides or fragments thereof by recombinant techniques.
[0178] As used herein, a "vector" is any construct capable of
delivering one or more polynucleotide(s) of interest to a host cell
when the vector is introduced to the host cell. An "expression
vector" is capable of delivering and expressing the one or more
polynucleotide(s) of interest as an encoded polypeptide in a host
cell into which the expression vector has been introduced. Thus, in
an expression vector, the polynucleotide of interest is positioned
for expression in the vector by being operably linked with
regulatory elements such as a promoter, enhancer, and/or a poly-A
tail, either within the vector or in the genome of the host cell at
or near or flanking the integration site of the polynucleotide of
interest such that the polynucleotide of interest will be
translated in the host cell introduced with the expression
vector.
[0179] A vector can be introduced into the host cell by methods
known in the art, e.g., electroporation, chemical transfection
(e.g., DEAE-dextran), transformation, transfection, and infection
and/or transduction (e.g., with recombinant virus). Thus,
non-limiting examples of vectors include viral vectors (which can
be used to generate recombinant virus), naked DNA or RNA, plasmids,
cosmids, phage vectors, and DNA or RNA expression vectors
associated with cationic condensing agents.
[0180] In some implementations, a polynucleotide disclosed herein
(e.g., a polynucleotide that encodes a polypeptide disclosed
herein) is introduced using a viral expression system (e.g.,
vaccinia or other pox virus, retrovirus, or adenovirus), which may
involve the use of a non-pathogenic (defective), replication
competent virus, or may use a replication defective virus. In the
latter case, viral propagation generally will occur only in
complementing virus packaging cells. Suitable systems are
disclosed, for example, in Fisher-Hoch et al., 1989, Proc. Natl.
Acad. Sci. USA 86:317-321; Flexner et al., 1989, Ann. N.Y. Acad
Sci. 569:86-103; Flexner et al., 1990, Vaccine, 8:17-21; U.S. Pat.
Nos. 4,603,112, 4,769,330, and 5,017,487; WO 89/01973; U.S. Pat.
No. 4,777,127; GB 2,200,651; EP 0,345,242; WO 91/02805;
Berkner-Biotechniques, 6:616-627, 1988; Rosenfeld et al., 1991,
Science, 252:431-434; Kolls et al., 1994, Proc. Natl. Acad. Sci.
USA, 91:215-219; Kass-Eisler et al., 1993, Proc. Natl. Acad. Sci.
USA, 90:11498-11502; Guzman et al., 1993, Circulation,
88:2838-2848; and Guzman et al., 1993, Cir. Res., 73:1202-1207.
Techniques for incorporating DNA into such expression systems are
well known to those of ordinary skill in the art. The DNA may also
be "naked," as described, for example, in Ulmer et al., 1993,
Science, 259:1745-1749, and Cohen, 1993, Science, 259:1691-1692.
The uptake of naked DNA may be increased by coating the DNA onto
biodegradable beads that are efficiently transported into the
cells.
[0181] For expression, the DNA insert comprising an
antibody-encoding or polypeptide-encoding polynucleotide disclosed
herein can be operatively linked to an appropriate promoter (e.g.,
a heterologous promoter), such as the phage lambda PL promoter, the
E. coli lac, trp and tac promoters, the SV40 early and late
promoters and promoters of retroviral LTRs, to name a few. Other
suitable promoters are known to the skilled artisan. The expression
constructs can further contain sites for transcription initiation,
termination and, in the transcribed region, a ribosome binding site
for translation. The coding portion of the mature transcripts
expressed by the constructs may include a translation initiating at
the beginning and a termination codon (UAA, UGA, or UAG)
appropriately positioned at the end of the polypeptide to be
translated.
[0182] As indicated, the expression vectors can include at least
one selectable marker. Such markers include dihydrofolate reductase
or neomycin resistance for eukaryotic cell culture and tetracycline
or ampicillin resistance genes for culturing in E. coli and other
bacteria. Representative examples of appropriate hosts include, but
are not limited to, bacterial cells, such as E. coli, Streptomyces,
and Salmonella typhimurium cells; fungal cells, such as yeast
cells; insect cells such as Drosophila S2 and Spodoptera Sf9 cells;
animal cells such as CHO, COS, Bowes melanoma, and HK 293 cells;
and plant cells. Appropriate culture mediums and conditions for the
host cells described herein are known in the art.
[0183] Non-limiting vectors for use in bacteria include pQE70,
pQE60 and pQE-9, available from Qiagen; pBS vectors, Phagescript
vectors, Bluescript vectors, pNH8A, pNH16a, pNH18A, pNH46A,
available from Stratagene; and ptrc99a, pKK223-3, pKK233-3, pDR540,
pRIT5 available from Pharmacia. Non-limiting eukaryotic vectors
include pWLNEO, pSV2CAT, pOG44, pXT1 and pSG available from
Stratagene; and pSVK3, pBPV, pMSG and pSVL available from
Pharmacia. Other suitable vectors will be readily apparent to the
skilled artisan.
[0184] Non-limiting bacterial promoters suitable for use include
the E. coli lacI and lacZ promoters, the T3 and T7 promoters, the
gpt promoter, the lambda PR and PL promoters and the trp promoter.
Suitable eukaryotic promoters include the CMV immediate early
promoter, the HSV thymidine kinase promoter, the early and late
SV40 promoters, the promoters of retroviral LTRs, such as those of
the Rous sarcoma virus (RSV), and metallothionein promoters, such
as the mouse metallothionein-I promoter.
[0185] In the yeast Saccharomyces cerevisiae, a number of vectors
containing constitutive or inducible promoters such as alpha
factor, alcohol oxidase, and PGH may be used. For reviews, see
Ausubel et al. (1989) Current Protocols in Molecular Biology, John
Wiley & Sons, New York, N.Y, and Grant et al., Methods
Enzymol., 153: 516-544 (1997).
[0186] Introduction of the construct into the host cell can be
effected by calcium phosphate transfection, DEAE-dextran mediated
transfection, cationic lipid-mediated transfection,
electroporation, transduction, infection or other methods. Such
methods are described in many standard laboratory manuals, such as
Davis et al., Basic Methods In Molecular Biology (1986), which is
incorporated herein by reference in its entirety.
[0187] Transcription of DNA encoding an antibody of the present
disclosure by higher eukaryotes may be increased by inserting an
enhancer sequence into the vector. Enhancers are cis-acting
elements of DNA, usually about from 10 to 300 bp that act to
increase transcriptional activity of a promoter in a given host
cell-type. Examples of enhancers include the SV40 enhancer, which
is located on the late side of the replication origin at base pairs
100 to 270, the cytomegalovirus early promoter enhancer, the
polyoma enhancer on the late side of the replication origin, and
adenovirus enhancers.
[0188] For secretion of the translated protein into the lumen of
the endoplasmic reticulum, into the periplasmic space or into the
extracellular environment, appropriate secretion signals may be
incorporated into the expressed polypeptide. The signals may be
endogenous to the polypeptide or they may be heterologous
signals.
[0189] The polypeptide (e.g., antibody) can be expressed in a
modified form, such as a fusion protein (e.g., a GST-fusion) or
with a histidine-tag, and may include not only secretion signals,
but also additional heterologous functional regions. For instance,
a region of additional amino acids, particularly charged amino
acids, may be added to the N-terminus of the polypeptide to improve
stability and persistence in the host cell, during purification, or
during subsequent handling and storage. Also, peptide moieties can
be added to the polypeptide to facilitate purification. Such
regions can be removed prior to final preparation of the
polypeptide. The addition of peptide moieties to polypeptides to
engender secretion or excretion, to improve stability and to
facilitate purification, among others, are familiar and routine
techniques in the art.
Methods of Treatment
[0190] The antibodies or antibody or antigen-binding fragments
thereof of the present disclosure can be used for various
therapeutic purposes. In one aspect, the disclosure provides
methods for treating a cancer in a subject, methods of reducing the
rate of the increase of volume of a tumor in a subject over time,
methods of reducing the risk of developing a metastasis, or methods
of reducing the risk of developing an additional metastasis in a
subject. In some embodiments, the treatment can halt, slow, retard,
or inhibit progression of a cancer. In some embodiments, the
treatment can result in the reduction of in the number, severity,
and/or duration of one or more symptoms of the cancer in a
subject.
[0191] In one aspect, the disclosure features methods that include
administering a therapeutically effective amount of an antibody or
antigen-binding fragment thereof disclosed herein to a subject in
need thereof (e.g., a subject having, or identified or diagnosed as
having, a cancer), e.g., breast cancer (e.g., triple-negative
breast cancer), carcinoid cancer, cervical cancer, endometrial
cancer, glioma, head and neck cancer, liver cancer, lung cancer,
small cell lung cancer, lymphoma, melanoma, ovarian cancer,
pancreatic cancer, prostate cancer, renal cancer, colorectal
cancer, gastric cancer, testicular cancer, thyroid cancer, bladder
cancer, urethral cancer, or hematologic malignancy. In some
embodiments, the cancer is unresectable melanoma or metastatic
melanoma, non-small cell lung carcinoma (NSCLC), small cell lung
cancer (SCLC), bladder cancer, or metastatic hormone-refractory
prostate cancer. In some embodiments, the subject has a solid
tumor. In some embodiments, the cancer is squamous cell carcinoma
of the head and neck (SCCHN), renal cell carcinoma (RCC),
triple-negative breast cancer (TNBC), or colorectal carcinoma. In
some embodiments, the subject has Hodgkin's lymphoma. In some
embodiments, the subject has triple-negative breast cancer (TNBC),
gastric cancer, urothelial cancer, Merkel-cell carcinoma, or head
and neck cancer.
[0192] In some embodiments, the compositions and methods disclosed
herein can be used for treatment of patients at risk for a cancer.
Patients with cancer can be identified with various methods known
in the art.
[0193] As used herein, by an "effective amount" is meant an amount
or dosage sufficient to effect beneficial or desired results
including halting, slowing, retarding, or inhibiting progression of
a disease, e.g., a cancer. An effective amount will vary depending
upon, e.g., an age and a body weight of a subject to which the
antibody, antigen binding fragment, antibody-encoding
polynucleotide, vector comprising the polynucleotide, and/or
compositions thereof is to be administered, a severity of symptoms
and a route of administration, and thus administration can be
determined on an individual basis.
[0194] An effective amount can be administered in one or more
administrations. By way of example, an effective amount of an
antibody or an antigen binding fragment is an amount sufficient to
ameliorate, stop, stabilize, reverse, inhibit, slow and/or delay
progression of a cancer in a patient or is an amount sufficient to
ameliorate, stop, stabilize, reverse, slow and/or delay
proliferation of a cell (e.g., a biopsied cell, any of the cancer
cells described herein, or cell line (e.g., a cancer cell line)) in
vitro. As is understood in the art, an effective amount of an
antibody or antigen binding fragment may vary, depending on, inter
alia, patient history as well as other factors such as the type
(and/or dosage) of antibody used.
[0195] Effective amounts and schedules for administering the
antibodies, antibody-encoding polynucleotides, and/or compositions
disclosed herein may be determined empirically, and making such
determinations is within the skill in the art. Those skilled in the
art will understand that the dosage that must be administered will
vary depending on, for example, the mammal that will receive the
antibodies, antibody-encoding polynucleotides, and/or compositions
disclosed herein, the route of administration, the particular type
of antibodies, antibody-encoding polynucleotides, antigen binding
fragments, and/or compositions disclosed herein used and other
drugs being administered to the mammal. Guidance in selecting
appropriate doses for antibody or antigen binding fragment can be
found in the literature on therapeutic uses of antibodies and
antigen binding fragments, e.g., Handbook of Monoclonal Antibodies,
Ferrone et al., eds., Noges Publications, Park Ridge, N.J., 1985,
ch. 22 and pp. 303-357; Smith et al., Antibodies in Human Diagnosis
and Therapy, Haber et al., eds., Raven Press, New York, 1977, pp.
365-389.
[0196] A typical daily dosage of an effective amount of an antibody
is 0.01 mg/kg to 100 mg/kg. In some embodiments, the dosage can be
less than 100 mg/kg, 10 mg/kg, 9 mg/kg, 8 mg/kg, 7 mg/kg, 6 mg/kg,
5 mg/kg, 4 mg/kg, 3 mg/kg, 2 mg/kg, 1 mg/kg, 0.5 mg/kg, or 0.1
mg/kg. In some embodiments, the dosage can be greater than 10
mg/kg, 9 mg/kg, 8 mg/kg, 7 mg/kg, 6 mg/kg, 5 mg/kg, 4 mg/kg, 3
mg/kg, 2 mg/kg, 1 mg/kg, 0.5 mg/kg, 0.1 mg/kg, 0.05 mg/kg, or 0.01
mg/kg. In some embodiments, the dosage is about 10 mg/kg, 9 mg/kg,
8 mg/kg, 7 mg/kg, 6 mg/kg, 5 mg/kg, 4 mg/kg, 3 mg/kg, 2 mg/kg, 1
mg/kg, 0.9 mg/kg, 0.8 mg/kg, 0.7 mg/kg, 0.6 mg/kg, 0.5 mg/kg, 0.4
mg/kg, 0.3 mg/kg, 0.2 mg/kg, or 0.1 mg/kg.
[0197] In any of the methods described herein, the at least one
antibody, antigen-binding fragment thereof, or pharmaceutical
composition (e.g., any of the antibodies, antigen-binding
fragments, or pharmaceutical compositions described herein) and,
optionally, at least one additional therapeutic agent can be
administered to the subject at least once a week (e.g., once a
week, twice a week, three times a week, four times a week, once a
day, twice a day, or three times a day). In some embodiments, at
least two different antibodies and/or antigen-binding fragments are
administered in the same composition (e.g., a liquid composition).
In some embodiments, at least one antibody or antigen-binding
fragment and at least one additional therapeutic agent are
administered in the same composition (e.g., a liquid composition).
In some embodiments, the at least one antibody or antigen-binding
fragment and the at least one additional therapeutic agent are
administered in two different compositions (e.g., a liquid
composition containing at least one antibody or antigen-binding
fragment and a solid oral composition containing at least one
additional therapeutic agent). In some embodiments, the at least
one additional therapeutic agent is administered as a pill, tablet,
or capsule. In some embodiments, the at least one additional
therapeutic agent is administered in a sustained-release oral
formulation.
[0198] In some embodiments, the one or more additional therapeutic
agents can be administered to the subject prior to, or after
administering the at least one antibody, antigen-binding antibody
fragment, or pharmaceutical composition (e.g., any of the
antibodies, antigen-binding antibody fragments, or pharmaceutical
compositions described herein). In some embodiments, the one or
more additional therapeutic agents and the at least one antibody,
antigen-binding antibody fragment, or pharmaceutical composition
(e.g., any of the antibodies, antigen-binding antibody fragments,
or pharmaceutical compositions described herein) are administered
to the subject such that there is an overlap in the bioactive
period of the one or more additional therapeutic agents and the at
least one antibody or antigen-binding fragment (e.g., any of the
antibodies or antigen-binding fragments described herein) in the
subject.
[0199] In some embodiments, the subject can be administered the at
least one antibody, antigen-binding antibody fragment, or
pharmaceutical composition (e.g., any of the antibodies,
antigen-binding antibody fragments, or pharmaceutical compositions
described herein) over an extended period of time (e.g., over a
period of at least 1 week, 2 weeks, 3 weeks, 1 month, 2 months, 3
months, 4 months, 5 months, 6 months, 7 months, 8 months, 9 months,
10 months, 11 months, 12 months, 1 year, 2 years, 3 years, 4 years,
or 5 years). A skilled medical professional may determine the
length of the treatment period using any of the methods described
herein for diagnosing or following the effectiveness of treatment
(e.g., the observation of at least one symptom of cancer). As
described herein, a skilled medical professional can also change
the identity and number (e.g., increase or decrease) of antibodies
or antigen-binding antibody fragments (and/or one or more
additional therapeutic agents) administered to the subject and can
also adjust (e.g., increase or decrease) the dosage or frequency of
administration of at least one antibody or antigen-binding antibody
fragment (and/or one or more additional therapeutic agents) to the
subject based on an assessment of the effectiveness of the
treatment (e.g., using any of the methods described herein and
known in the art).
[0200] In some embodiments, one or more additional therapeutic
agents can be administered to the subject. The additional
therapeutic agent can comprise one or more inhibitors selected from
the group consisting of an inhibitor of B-Raf, an EGFR inhibitor,
an inhibitor of a MEK, an inhibitor of ERK, an inhibitor of K-Ras,
an inhibitor of c-Met, an inhibitor of anaplastic lymphoma kinase
(ALK), an inhibitor of a phosphatidylinositol 3-kinase (PI3K), an
inhibitor of an Akt, an inhibitor of mTOR, a dual PI3K/mTOR
inhibitor, an inhibitor of Bruton's tyrosine kinase (BTK), and an
inhibitor of Isocitrate dehydrogenase 1 (IDH1) and/or Isocitrate
dehydrogenase 2 (IDH2). In some embodiments, the additional
therapeutic agent is an inhibitor of indoleamine 2,3-dioxygenase-1)
(IDO1) (e.g., epacadostat).
[0201] In some embodiments, the additional therapeutic agent can
comprise one or more inhibitors selected from the group consisting
of an inhibitor of HER3, an inhibitor of LSD1, an inhibitor of
MDM2, an inhibitor of BCL2, an inhibitor of CHK1, an inhibitor of
activated hedgehog signaling pathway, and an agent that selectively
degrades the estrogen receptor.
[0202] In some embodiments, the additional therapeutic agent can
comprise one or more therapeutic agents selected from the group
consisting of Trabectedin, nab-paclitaxel, Trebananib, Pazopanib,
Cediranib, Palbociclib, everolimus, fluoropyrimidine, IFL,
regorafenib, Reolysin, Alimta, Zykadia, Sutent, temsirolimus,
axitinib, everolimus, sorafenib, Votrient, Pazopanib, IMA-901,
AGS-003, cabozantinib, Vinflunine, an Hsp90 inhibitor, Ad-GM-CSF,
Temazolomide, IL-2, IFNa, vinblastine, Thalomid, dacarbazine,
cyclophosphamide, lenalidomide, azacytidine, lenalidomide,
bortezomid, amrubicine, carfilzomib, pralatrexate, and
enzastaurin.
[0203] In some embodiments, the additional therapeutic agent can
comprise one or more therapeutic agents selected from the group
consisting of an adjuvant, a TLR agonist, tumor necrosis factor
(TNF) alpha, IL-1, HMGB1, an IL-10 antagonist, an IL-4 antagonist,
an IL-13 antagonist, an IL-17 antagonist, an HVEM antagonist, an
ICOS agonist, a treatment targeting CX3CL1, a treatment targeting
CXCL9, a treatment targeting CXCL10, a treatment targeting CCL5, an
LFA-1 agonist, an ICAM1 agonist, and a Selectin agonist.
[0204] In some embodiments, carboplatin, nab-paclitaxel,
paclitaxel, cisplatin, pemetrexed, gemcitabine, FOLFOX, or FOLFIRI
are administered to the subject.
[0205] In some embodiments, the additional therapeutic agent is an
anti-OX40 antibody, an anti-PD-L1 antibody, an anti-PD-L2 antibody,
an anti-LAG-3 antibody, an anti-TIGIT antibody, an anti-BTLA
antibody, an anti-CTLA-4 antibody, or an anti-GITR antibody.
[0206] Methods of modifying and using the anti-PD-1 antibodies are
described, e.g., in US20170247454, US 20170081409 A1, US
20170044259 A1, and US 20160159905; each of which is incorporated
herein by reference in its entirety.
Pharmaceutical Compositions and Routes of Administration
[0207] Also provided herein are pharmaceutical compositions that
contain at least one (e.g., one, two, three, or four) of the
antibodies or antigen-binding fragments described herein. Two or
more (e.g., two, three, or four) of any of the antibodies or
antigen-binding fragments described herein can be present in a
pharmaceutical composition in any combination. The pharmaceutical
compositions may be formulated in any manner known in the art.
[0208] Pharmaceutical compositions are formulated to be compatible
with their intended route of administration (e.g., intravenous,
intraarterial, intramuscular, intradermal, subcutaneous, or
intraperitoneal). The compositions can include a sterile diluent
(e.g., sterile water or saline), a fixed oil, polyethylene glycol,
glycerine, propylene glycol or other synthetic solvents,
antibacterial or antifungal agents, such as benzyl alcohol or
methyl parabens, chlorobutanol, phenol, ascorbic acid, thimerosal,
and the like, antioxidants, such as ascorbic acid or sodium
bisulfate, chelating agents, such as ethylenediaminetetraacetic
acid, buffers, such as acetates, citrates, or phosphates, and
isotonic agents, such as sugars (e.g., dextrose), polyalcohols
(e.g., mannitol or sorbitol), or salts (e.g., sodium chloride), or
any combination thereof. Liposomal suspensions can also be used as
pharmaceutically acceptable carriers (see, e.g., U.S. Pat. No.
4,522,811). Preparations of the compositions can be formulated and
enclosed in ampules, disposable syringes, or multiple dose vials.
Where required (as in, for example, injectable formulations),
proper fluidity can be maintained by, for example, the use of a
coating, such as lecithin, or a surfactant. Absorption of the
antibody or antigen-binding fragment thereof can be prolonged by
including an agent that delays absorption (e.g., aluminum
monostearate and gelatin). Alternatively, controlled release can be
achieved by implants and microencapsulated delivery systems, which
can include biodegradable, biocompatible polymers (e.g., ethylene
vinyl acetate, polyanhydrides, polyglycolic acid, collagen,
polyorthoesters, and polylactic acid; Alza Corporation and Nova
Pharmaceutical, Inc.).
[0209] Compositions containing one or more of any of the antibodies
or antigen-binding fragments described herein can be formulated for
parenteral (e.g., intravenous, intraarterial, intramuscular,
intradermal, subcutaneous, or intraperitoneal) administration in
dosage unit form (i.e., physically discrete units containing a
predetermined quantity of active compound for ease of
administration and uniformity of dosage).
[0210] Toxicity and therapeutic efficacy of compositions can be
determined by standard pharmaceutical procedures in cell cultures
or experimental animals (e.g., monkeys). One can, for example,
determine the LD50 (the dose lethal to 50% of the population) and
the ED50 (the dose therapeutically effective in 50% of the
population): the therapeutic index being the ratio of LD50:ED50.
Agents that exhibit high therapeutic indices are preferred. Where
an agent exhibits an undesirable side effect, care should be taken
to minimize potential damage (i.e., reduce unwanted side effects).
Toxicity and therapeutic efficacy can be determined by other
standard pharmaceutical procedures.
[0211] Data obtained from cell culture assays and animal studies
can be used in formulating an appropriate dosage of any given agent
for use in a subject (e.g., a human). A therapeutically effective
amount of the one or more (e.g., one, two, three, or four)
antibodies or antigen-binding fragments thereof (e.g., any of the
antibodies or antibody fragments described herein) will be an
amount that treats the disease in a subject (e.g., kills cancer
cells) in a subject (e.g., a human subject identified as having
cancer), or a subject identified as being at risk of developing the
disease (e.g., a subject who has previously developed cancer but
now has been cured), decreases the severity, frequency, and/or
duration of one or more symptoms of a disease in a subject (e.g., a
human). The effectiveness and dosing of any of the antibodies or
antigen-binding fragments described herein can be determined by a
health care professional or veterinary professional using methods
known in the art, as well as by the observation of one or more
symptoms of disease in a subject (e.g., a human). Certain factors
may influence the dosage and timing required to effectively treat a
subject (e.g., the severity of the disease or disorder, previous
treatments, the general health and/or age of the subject, and the
presence of other diseases).
[0212] Exemplary doses include milligram or microgram amounts of
any of the antibodies or antigen-binding fragments described herein
per kilogram of the subject's weight (e.g., about 1 .mu.g/kg to
about 500 mg/kg; about 100 .mu.g/kg to about 500 mg/kg; about 100
.mu.g/kg to about 50 mg/kg; about 10 .mu.g/kg to about 5 mg/kg;
about 10 .mu.g/kg to about 0.5 mg/kg; or about 1 .mu.g/kg to about
50 .mu.g/kg). While these doses cover a broad range, one of
ordinary skill in the art will understand that therapeutic agents,
including antibodies and antigen-binding fragments thereof, vary in
their potency, and effective amounts can be determined by methods
known in the art. Typically, relatively low doses are administered
at first, and the attending health care professional or veterinary
professional (in the case of therapeutic application) or a
researcher (when still working at the development stage) can
subsequently and gradually increase the dose until an appropriate
response is obtained. In addition, it is understood that the
specific dose level for any particular subject will depend upon a
variety of factors including the activity of the specific compound
employed, the age, body weight, general health, gender, and diet of
the subject, the time of administration, the route of
administration, the rate of excretion, and the half-life of the
antibody or antibody fragment in vivo.
[0213] The pharmaceutical compositions can be included in a
container, pack, or dispenser together with instructions for
administration. The disclosure also provides methods of
manufacturing the antibodies or antigen binding fragments thereof
for various uses as described herein.
EXAMPLES
[0214] The invention is further described in the following
examples, which do not limit the scope of the invention described
in the claims.
Example 1. Generating Mouse Anti-hPD-1 Antibodies
[0215] To generate mouse antibodies against human PD-1 (hPD-1; SEQ
ID NO: 22), 6-8 weeks old female BALB/c mice were immunized with
human PD-1. Anti-hPD-1 antibodies were collected by the methods as
described below and shown in FIG. 1 and FIG. 2.
Immunization of Mice
[0216] 6-8 weeks old female BALB/c mice were immunized with
His-tagged human PD-1 proteins at 20 .mu.g/mouse at a concentration
of 100 .mu.g/ml. The His-tagged human PD-1 proteins were emulsified
with adjuvant and injected at four positions on the back of the
mice. For the first subcutaneous (s.c.) injection, the diluted
antigen was emulsified with Complete Freund's Adjuvant (CFA) in
equal volume. In the following subcutaneous injections, the protein
was emulsified with Incomplete Freund's Adjuvant (IFA) in equal
volume. Three days after the third injection or
theboosterimmunization, blood (serum) was collected and analyzed
for antibody titer using ELISA.
[0217] In another experiment, 6-8 weeks old female BALB/c mice were
immunized by injecting the expression plasmid encoding human PD-1
into the mice. The plasmids encoding the antigen were injected into
the tibialis anterior muscle (intramuscular injection; i.m.
injection) of the mice by using gene guns at the concentration of
1000 .mu.g/ml at 60 .mu.g per mouse. At least four injections were
performed with at least 14 days between two injections. Blood
(serum) was collected seven days after the last immunization and
the serum was tested for antibody titer by ELISA.
[0218] Procedures to enhance immunization were also performed at
least fourteen days after the previous immunization (either by
injecting the plasmid or by injecting the proteins). CHO cells that
express PD-1 antigen on the surface were intravenously injected
into the mice through tail veins. Spleen was then collected four
days after the injection.
Fusion of SP2/0 Cells and Spleen Cells
[0219] Spleen tissues were grinded. Spleen cells were first
selected by CD3c Microbeads and Anti-Mouse IgM Microbeads, and then
fused with SP2/0 cells. The cells were then plated in 96-well
plates with hypoxanthine-aminopterin-thymidine (HAT) medium.
Primary Screening of Hybridoma
[0220] Primary screening of the hybridoma supernatant in the
96-well plates was performed using Fluorescence-Activated Cell
Sorting (FACS) pursuant to standard procedures. Chinese hamster
ovary (CHO) cells were added to 96-well plates (2.times.10.sup.4
cells per well) before the screening. 50 .mu.l of supernatant was
used. The antibodies that were used in experiments were [0221] (1)
Fluorescein (FITC)-conjugated AffiniPure F(ab).sub.2 Fragment Goat
Anti-Mouse IgG, Fc.gamma. Fragment Specific, and [0222] (2) Alexa
Fluor.RTM. 647-conjugated AffiniPure F(ab)2 Fragment Goat
Anti-Human IgG, Fc.gamma. Fragment Specific.
Sub-Cloning
[0223] Sub-cloning was performed using ClonePix.RTM. 2. In short,
the positive wells identified during the primary screening were
transferred to semisolid medium, and IgG positive clones were
identified and tested. FITC anti-mouse IgG Fc antibody was
used.
Ascites Fluid Antibodies
[0224] 1.times.10.sup.6 positive hybridoma cells were injected
intraperitoneally to B-NDG.RTM. mice (Beijing Biocytogen, Beijing,
China). Monoclonal antibodies were produced by growing hybridoma
cells within the peritoneal cavity of the mouse. The hybridoma
cells multiplied and produced ascites fluid in the abdomens of the
mice. The fluid contained a high concentration of antibody which
can be harvested for later use.
Purification of Antibodies
[0225] Antibodies in ascites fluid were purified using GE AKTA.TM.
protein chromatography (GE Healthcare, Chicago, Ill., United
States). 25-1A7 ("1A7"), 18-3F1 ("3F1"), and 3-6G1 ("6G1") were
among the mouse antibodies produced by the methods described
above.
[0226] The VH, VL and CDR regions of the antibodies were
determined. The heavy chain CDR1, CDR2, CDR3, and light chain CDR1,
CDR2, and CDR3 amino acid sequences of 1A7 are shown in SEQ ID NOs:
1-6 (Kabat numbering) or SEQ ID NOs: 16, 17, 3, 4, 5, 6 (Chothia
numbering).
[0227] The heavy chain CDR1, CDR2, CDR3, and light chain CDR1,
CDR2, and CDR3 amino acid sequences of 3F1 are shown in SEQ ID NOs:
7-12 (Kabat numbering) or SEQ ID NOs: 18, 19, 9, 10, 11, 12
(Chothia numbering).
[0228] The heavy chain CDR1, CDR2, CDR3, and light chain CDR1,
CDR2, and CDR3 amino acid sequences of 6G1 are shown in SEQ ID NOs:
7, 13, 14, 10, 11, 15 (Kabat numbering) or SEQ ID NOs: 20, 21, 14,
10, 11, 15 (Chothia numbering).
Example 2. Humanization of the Mice Antibodies
[0229] The starting point for humanization was the mouse antibodies
(e.g., 1A7 and 3F1). The amino acid sequences for the heavy chain
variable region and the light chain variable region of these mouse
antibodies were determined.
[0230] Three humanized heavy chain variable region variants (SEQ ID
NOs: 26-28) and three humanized light chain variable region
variants (SEQ ID NOs: 29-31) for 1A7 were constructed, containing
different modifications or substitutions.
[0231] Four humanized heavy chain variable region variants (SEQ ID
NOs: 32-35) and three humanized light chain variable region
variants (SEQ ID NOs: 36-38) for 3F1 were constructed, containing
different modifications or substitutions.
[0232] These humanized heavy chain variable region variants can be
combined with any of the light chain variable region variants based
on the same mouse antibody. For example, 1A7-H1 (SEQ ID NO: 26) can
be combined with any humanized light chain variable region variant
based on the same mouse antibody 1A7 (e.g., 1A7-K3 (SEQ ID NO:
31)), and the antibody is labeled accordingly (e.g., 1A7-H1K3).
[0233] These humanized antibodies were then generated with the use
of BioLuminate.RTM. 1.0 (Schrodinger, Shanghai, China).
Example 3. In Vitro Testing of the Mouse Anti-hPD-1 Antibodies:
Blocking the Binding of Human PD-1 (hPD-1) and Human PD-L1
(hPD-L1)
[0234] Blocking assays were performed to determine whether the
anti-hPD-1 antibodies can block the binding between hPD-1 and its
ligand hPD-L1.
[0235] The anti-hPD-1 antibodies were collected from mouse ascites
fluid and purified by chromatography. 25 .mu.l CHO cells
transiently transfected with human PD-1 were added to each well in
a plate. The purified antibodies were titrated to final
concentrations of 50, 5, 0.5, 0.05, 0.005 .mu.g/ml. The titrated
antibodies were added to each well at 25 .mu.l per well at
4.degree. C. and incubated for 30 minutes.
[0236] 50 .mu.l of Bitoin-hPD-L1 was added to each well (with a
final concentration of 2 .mu.g/ml in each well). The cells with
Bitoin-hPD-L1 and the antibodies were incubated at 4.degree. C. for
15 minutes.
[0237] After being washed with phosphate-buffered saline (PBS)
twice, 50 .mu.l of FITC labeled anti-mouse IgG Fc antibody
(anti-mIgG Fc-FITC) at 1:100 dilution and PE-labeled Streptavidin
(Streptavidin-PE) at 1:100 dilution were added into each well, and
incubated for 30 minutes at 4.degree. C., followed by PBS wash. The
signals for FITC and PE were determined by flow cytometry.
[0238] As shown in FIG. 3, when the concentration of the mouse
anti-PD-1 antibodies 25-1A7, 18-3F1, and 03-6G1 increased, the
signal for cells binging to PD-L1 decreased (y axis), while the
signal for cells binding to the mouse ant-PD-1 antibodies
increased, suggesting that the binding between human PD-1 and PD-L1
was blocked by the anti-hPD-1 antibodies.
Example 4. Cross-Reactivity of Anti-hPD-1 Antibodies Against
Monkey, Mouse, and Human-Mouse Chimeric PD-1
[0239] In each experiment, the CHO cells were transfected with
mouse PD-1 (mPD-1, SEQ ID NO: 23), monkey (rhesus macaque) PD-1
(rmPD-1, SEQ ID NO: 24), or chimeric (mouse and human) PD-1
(chiPD-1, SEQ ID NO: 25).
[0240] 25 .mu.l CHO cells were added to each well. 25 .mu.l
purified anti-hPD-1 antibodies (1 .mu.g/ml) (1A7, 3F1, or 6G1) were
added to each well and were incubated at 4.degree. C. for 30
minutes.
[0241] After being washed with PBS (1200 rmp, 5 min) twice, 50
.mu.l of FITC labeled anti-mouse IgG Fc antibody (anti-mIgG
Fc-FITC) was added into each well 1:500 dilution, followed by
incubated at 4.degree. C. for 30 minutes, and then PBS wash (1200
rmp, 5 min). The signals for FITC were determined by flow
cytometry.
[0242] As shown in FIG. 4, 1A7, 3F1, and 6G1 did not cross react
with mouse PD-1, but had strong cross reactivity with rmPD-1 and
some cross reactivity with chimeric PD-1. In FIG. 4, NC stands for
negative control.
Example 5. Binding Affinity of Anti-hPD-1 Antibodies
[0243] The binding affinity of the anti-hPD-1 antibodies were
measured using surface plasmon resonance (SPR) using Biacore.TM.
(Biacore.TM., INC, Piscataway N.J.) T200 biosensor equipped with
pre-immobilized Protein A sensor chips.
[0244] Anti-hPD-1 antibody 1A7-mHvKv-IgG4-S228P (1 .mu.g/mL) were
injected into Biacore.TM. T200 biosensor at 10 .mu.L/min for 30
seconds to achieve to a desired protein density (about 67 response
units (RU)). Histidine-tagged human PD-1 proteins (hPD-1-His) at
the concentration of 200, 100, 50, 25, 12.5, 6.25, 3.125, 1.5625 nM
were then injected at 30 .mu.L/min for 100 seconds. Dissociation
was monitored for 400 seconds. The chip was regenerated after the
last injection of each titration with Glycine (pH 2.0, 30 .mu.L/min
for 12 seconds). The result for 1A7-mHvKv-IgG4-S228P is shown in
FIG. 5.
[0245] Kinetic association rates (kon) and dissociation rates
(koff) were obtained simultaneously by fitting the data globally to
a 1:1 Langmuir binding model (Karlsson, R. Roos, H. Fagerstam, L.
Petersson, B., 1994. Methods Enzymology 6. 99-110) using
Biacore.TM. T200 Evaluation Software 3.0. Affinities were deduced
from the quotient of the kinetic rate constants (KD=koff/kon).
[0246] As a person of ordinary skill in the art would understand,
the same method with appropriate adjustments for parameters (e.g.,
antibody concentration) was performed for each tested antibody. For
example, the graph showing the results of 3F1-mHvKv-IgG4-S228P is
shown in FIG. 6. The results for the tested antibodies are
summarized in Table 1 below.
TABLE-US-00001 TABLE 1 Association rate Dissociation rate Affinity
Anti-hPD-1 antibodies kon (1/Ms) koff (1/s) KD (M)
1A7-mHvKv-IgG4-S228P 4.07E+05 9.56E-04 2.35E-09 1A7-H1K1-IgG4-S228P
5.68E+04 2.72E-03 4.79E-08 1A7-H1K2-IgG4-S228P 8.26E+04 2.65E-03
3.21E-08 1A7-H1K3-IgG4-S228P 1.18E+05 1.19E-03 1.01E-08
1A7-H2K1-IgG4-S228P 4.89E+04 2.80E-03 5.73E-08 1A7-H2K2-IgG4-S228P
4.88E+04 2.82E-03 5.78E-08 1A7-H2K3-IgG4-S228P 1.15E+05 1.36E-03
1.19E-08 1A7-H3K1-IgG4-S228P 6.62E+04 2.64E-03 3.99E-08
1A7-H3K2-IgG4-S228P 4.81E+04 2.80E-03 5.82E-08 1A7-H3K3-IgG4-S228P
1.02E+05 1.32E-03 1.29E-08 3F1-mHvKv-IgG4-S228P 3.70E+03 1.28E-03
3.46E-07 3F1-H1K1-IgG4-S228P 4.81E+03 1.81E-03 3.76E-07
3F1-H1K2-IgG4-S228P 5.27E+03 1.55E-03 2.94E-07 3F1-H1K3-IgG4-S228P
4.79E+03 1.32E-03 2.75E-07 3F1-H2K1-IgG4-S228P 4.55E+03 1.92E-03
4.22E-07 3F1-H2K2-IgG4-S228P 4.81E+03 1.70E-03 3.54E-07
3F1-H2K3-IgG4-S228P 4.41E+03 1.45E-03 3.29E-07 3F1-H3K1-IgG4-S228P
4.53E+03 1.79E-03 3.95E-07 3F1-H3K2-IgG4-S228P 5.06E+03 1.50E-03
2.96E-07 3F1-H3K3-IgG4-S228P 4.38E+03 1.39E-03 3.18E-07
3F1-H4K1-IgG4-S228P 4.42E+03 2.04E-03 4.60E-07 3F1-H4K2-IgG4-S228P
4.80E+03 1.77E-03 3.69E-07 3F1-H4K3-IgG4-S228P 4.06E+03 1.61E-03
3.97E-07
[0247] Among these tested antibodies, 1A7 and 3F1 are mouse
anti-hPD-1 antibodies as described in Example 1. Based on 1A7 and
3F1, the chimeric anti-hPD-1 antibodies including
1A7-mHvKv-IgG4-S228P, and 3F1-mHvKv-IgG4-S228P were generated. The
chimeric antibodies have the heavy chain variable domain and the
light chain variable domain from the corresponding mouse anti-hPD-1
antibodies, with the constant domains from human IgG4 antibody
(including, e.g., the CL, CH1, CH2, and CH3 domains).
[0248] The tested antibodies also include humanized antibodies,
e.g., 1A7-H1K1-IgG4-S228P, 1A7-H1K2-IgG4-S228P,
1A7-H1K3-IgG4-S228P, 1A7-H2K1-IgG4-S228P, 1A7-H2K2-IgG4-S228P,
1A7-H2K3-IgG4-S228P, 1A7-H3K1-IgG4-S228P, 1A7-H3K2-IgG4-S228P,
1A7-H3K3-IgG4-S228P, 3F1-H1K1-IgG4-S228P, 3F1-H1K2-IgG4-S228P,
3F1-H1K3-IgG4-S228P, 3F1-H2K1-IgG4-S228P, 3F1-H2K2-IgG4-S228P,
3F1-H2K3-IgG4-S228P, 3F1-H3K1-IgG4-S228P, 3F1-H3K2-IgG4-S228P,
3F1-H3K3-IgG4-S228P, 3F1-H4K1-IgG4-S228P, 3F1-H4K2-IgG4-S228P, and
3F1-H4K3-IgG4-S228P. The humanized antibodies have human IgG4
antibody constant domains (including, e.g., the CL, CH1, CH2, and
CH3 domains). The humanized variable domains of the heavy chain are
numbered H1, H2, H3 etc.; and the humanized variable domains of the
light chain are numbered K1, K2, K3 etc. The sequences of the
humanized variable domains are summarized in FIG. 19. For example,
1A7-H1K1-IgG4-S228P is based on the mouse antibody 1A7 and has the
humanized heavy chain variable domain H1 (SEQ ID NO: 26) and
humanized light chain variable domain K1 (SEQ ID NO: 29).
Similarly, 3F1-H1K1-IgG4-5228P is based on mouse antibody 3F1 and
has humanized heavy chain variable domain H1 (SEQ ID NO: 32) and
humanized 9H3 light chain variable domain K1 (SEQ ID NO: 36).
[0249] The name and the sequences of the chimeric anti-PD-1
antibodies and the humanized anti-PD-1 antibodies are summarized in
Table 2 below. To facilitate production efficiency by avoiding
Fab-arm exchange, the Fc region of the antibodies was further
engineered to replace the serine at position 228 (EU numbering)
with proline (S228P).
TABLE-US-00002 TABLE 2 VH SEQ VL SEQ Type Antibody name ID NO: ID
NO: Constant regions Chimeric 1A7-m HyKy-IgG4- 39 40 Human IgG4
with S228P mutation antibody S228P based on 1A7 Humanized
1A7-H1K1-IgG4-S228P 26 29 Human IgG4 with S228P mutation antibodies
1A7-H1K2-IgG4-S228P 26 30 Human IgG4 with S228P mutation based on
1A7-H1K3-IgG4-S228P 26 31 Human IgG4 with S228P mutation 1A7
1A7-H2K1-IgG4-S228P 27 29 Human IgG4 with S228P mutation
1A7-H2K2-IgG4-S228P 27 30 Human IgG4 with S228P mutation
1A7-H2K3-IgG4-S228P 27 31 Human IgG4 with S228P mutation
1A7-H3K1-IgG4-S228P 28 29 Human IgG4 with S228P mutation
1A7-H3K2-IgG4-S228P 28 30 Human IgG4 with S228P mutation
1A7-H3K3-IgG4-S228P 28 31 Human IgG4 with S228P mutation Chimeric
3F1-mHyKy-IgG4- 41 42 Human IgG4 with S228P mutation antibody S228P
based on 3F1 Humanized 3F1-H1K1-IgG4-S228P 32 36 Human IgG4 with
S228P mutation antibodies 3F1-H1K2-IgG4-S228P 32 37 Human IgG4 with
S228P mutation based on 3F1-H1K3-IgG4-S228P 32 38 Human IgG4 with
S228P mutation 3F1 3F1-H2K1-IgG4-S228P 33 36 Human IgG4 with S228P
mutation 3F1-H2K2-IgG4-S228P 33 37 Human IgG4 with S228P mutation
3F1-H2K3-IgG4-S228P 33 38 Human IgG4 with S228P mutation
3F1-H3K1-IgG4-S228P 34 36 Human IgG4 with S228P mutation
3F1-H3K2-IgG4-S228P 34 37 Human IgG4 with S228P mutation
3F1-H3K3-IgG4-S228P 34 38 Human IgG4 with S228P mutation
3F1-H4K1-IgG4-S228P 35 36 Human IgG4 with S228P mutation
3F1-H4K2-IgG4-S228P 35 37 Human IgG4 with S228P mutation
3F1-H4K3-IgG4-S228P 35 38 Human IgG4 with S228P mutation
Example 6. Thermal Stability of Anti-hPD-1 Antibodies
[0250] Thermofluor assay was performed using the Protein Thermal
Shift.TM. Dye Kit (Thermo Fisher Scientific) and QuantStudio.TM. 5
Real Time PCR Systems (Thermo Fisher Scientific). This assay
measured thermostability using a fluorescent dye that binds to
hydrophobic patches exposed as the protein unfolds.
[0251] The experiments were performed according to the
manufacturer's protocol. 2 .mu.L of antibody, 10.5 .mu.L of water,
5 .mu.L of Protein Thermal Shift buffer, and 2.5 .mu.l of diluted
Protein Thermal Shift Dye were mixed. Samples were heated to
25.degree. C. at 1.6.degree. C./second, and then heated to
99.degree. C. at 0.05.degree. C./second.
[0252] The table below summarizes the Tm for four humanized
anti-hPD-1 antibodies.
TABLE-US-00003 TABLE 3 Thermal Variable Type stability Antibody
Domains (constant domains) (Tm.degree. C.) 1A7-H1K3-IgG4-S228P 1A7
H1K3 Human IgG4 with 75.94 S228P mutation 1A7-H2K3-IgG4-S228P 1A7
H2K3 Human IgG4 with 76.09 S228P mutation 3F1-H1K2-IgG4-S228P 3F1
H1K2 Human IgG4 with 82.82 S228P mutation 3F1-H1K3-IgG4-S228P 3F1
H1K3 Human IgG4 with 82.37 S228P mutation
Example 7. In Vivo Testing of Mouse and Chimeric Anti-hPD-1
Antibodies
[0253] In order to test the anti-hPD-1 antibodies in vivo and to
predict the effects of these antibodies in human, a humanized PD-1
mouse model was generated. The humanized PD-1 mouse model was
engineered to express a chimeric PD-1 protein (SEQ ID NO: 25)
wherein a part of the extracellular region of the mouse PD-1
protein was replaced with the corresponding human PD-1
extracellular region. The amino acid residues 31-141 of mouse PD-1
(SEQ ID NO: 23) were replaced by amino acid residues 31-141 of
human PD-1 (SEQ ID NO: 22). The humanized mouse model (B-hPD-1)
provides a new tool for testing new therapeutic treatments in a
clinical setting by significantly decreasing the difference between
clinical outcome in human and in ordinary mice expressing mouse
PD-1. A detailed description regarding humanized PD-1 mouse model
can be found in PCT/CN2017/090320, which is incorporated herein by
reference in its entirety.
[0254] The anti-hPD-1 antibodies were tested for their effect on
tumor growth in vivo in a model of colon carcinoma. MC-38 cancer
tumor cells (colon adenocarcinoma cell) were injected
subcutaneously in B-hPD-1 mice. When the tumors in the mice reached
a volume of 150.+-.50 mm.sup.3, the mice were randomly placed into
different groups based on the volume of the tumor (five mice in
each group).
[0255] The mice were then injected with physiological saline (PS)
and anti-hPD-1 antibodies by intraperitoneal administration. The
antibody was given on the first day and the fourth day of each week
for 3 weeks (6 injections in total).
[0256] The injected volume was calculated based on the weight of
the mouse at 1 mg/kg. The length of the long axis and the short
axis of the tumor were measured and the volume of the tumor was
calculated as 0.5.times.(long axis).times.(short axis). The weight
of the mice was also measured before the injection, when the mice
were placed into different groups (before the first antibody
injection), twice a week during the antibody injection period, and
before euthanization.
[0257] The tumor growth inhibition percentage (TGI %) was
calculated using the following formula: TGI
(%)=[1-(Ti-T0)/(Vi-V0)].times.100. Ti is the average tumor volume
in the treatment group on day i. T0 is the average tumor volume in
the treatment group on day zero. Vi is the average tumor volume in
the control group on day i. V0 is the average tumor volume in the
control group on day zero.
[0258] T-test was performed for statistical analysis. A TGI %
higher than 60% indicates significant suppression of tumor growth.
P<0.05 is a threshold to indicate significant difference.
In Vivo Results for Mouse Anti-hPD-1 Antibodies 25-1A7 and
18-3F1
[0259] In each of the four groups (G1, G2, G3, G4), B-hPD-1 mice
were injected with each physiological saline (PS) as a control
(G1), Keytruda (G2), the mouse anti-hPD-1 antibody 25-1A7 (G3), or
the mouse anti-hPD-1 antibody 18-3F1 (G4). The weight of the mice
was monitored during the entire treatment period. The weight of
mice in different groups all increased (FIG. 7 and FIG. 8). No
significant difference in weight was observed among the four
groups. The results showed that 1A7 and 3F1 were well tolerated and
not toxic to the mice.
[0260] The tumor size in groups treated with Keytruda, 1A7, or 3F1
increased to a lesser extent compared to the control group (FIG.
9). Particularly, the tumor size in G3 is smaller than G2; and the
tumor size in G4 is smaller than G2.
[0261] The TGI % at day 24 (24 days after grouping) was also
calculated as shown in the table below.
TABLE-US-00004 TABLE 4 Average P value tumor size at (against Group
Antibodies Day 24 TGI % control) G1 PS 1078 -- -- (1 mg/kg; i.p.
administration; twice a week, 6 injections in total) G2 Keytruda(1
mg/kg) 842 25.3% 0.691 (1 mg/kg; i.p. administration; twice a week,
6 injections in total) G3 25-1A7(1 mg/kg) 258 87.9% 0.153 (1 mg/kg;
i.p. administration; twice a week, 6 injections in total) G4
18-3F1(1 mg/kg) 646 46.3% 0.439 (1 mg/kg; i.p. administration;
twice a week, 6 injections in total)
In Vivo Results for Chimeric Anti-hPD-1 Antibodies
[0262] Chimeric anti-hPD-1 antibodies 03-6G1-mHvKv-IgG4-S228P
(Group 2, G2), 18-3F1-mHvKv-IgG4-S228P (Group 3, G3),
25-1A7-mHvKv-IgG4-S228P (Group 4, G4), and Keytruda (Group 5) were
administered into B-hPD-1 mice (humanized PD-1 mice) by
intraperitoneal administration. Physiological saline was injected
as a control (Group 1, G1). The injected amount of the antibodies
was calculated based on the weight of the mouse at 1 mg/kg. The
antibodies were given on the first day and the fourth day of each
week (6 injections in total).
[0263] The weight of the mice was monitored during the entire
treatment period. The weight of mice in different groups all
increased (FIG. 10, and FIG. 11). No significant difference in
weight was observed among the different groups. The results showed
that the anti-hPD-1 antibodies were well tolerated and not toxic to
the mice.
[0264] The tumor size showed significant difference in groups
treated with the chimeric antibodies compared to the control group
(FIG. 12).
[0265] The TGI % at day 20 (20 days after grouping) for each
treatment group was calculated as shown in the table below.
TABLE-US-00005 TABLE 5 Average tumor size at Group Antibodies Day
20 TGI % P value G1 PS 1427 -- -- G2 03-6G1-mHvKv-IgG4-S228P 564
66.0% 0.032 (1 mg/kg; i.p. administration; twice a week, 6
injections in total) G3 18-3F1-mHvKv-IgG4-S228P 700 55.6% 0.056 (1
mg/kg; i.p. administration; twice a week, 6 injections in total) G4
25-1A7-mHvKv-IgG4-S228P 356 81.9% 0.011 (1 mg/kg; i.p.
administration; twice a week, 6 injections in total) G5 Keytruda
200 93.8% 0.005 (1 mg/kg; i.p. administration; twice a week, 6
injections in total)
[0266] The results showed that chimeric antibodies
03-6G1-mHvKv-IgG4-S228P and 25-1A7-mHvKv-IgG4-S228P significantly
inhibited tumor growth. Among the three chimeric antibodies,
25-1A7-mHvKv-IgG4-S228P had the highest TGI %.
Example 8. In Vivo Testing of Humanized Anti-hPD-1 Antibodies
[0267] The humanized anti-hPD-1 antibodies were tested in PD-1
humanized mice (B-hPD-1) to demonstrate their effect on tumor
growth in vivo.
[0268] MC-38 cancer tumor cells (colon adenocarcinoma cell) were
injected subcutaneously in B-hPD-1 mice. When the tumors in the
mice reached a volume of 150.+-.50 mm.sup.3, the mice were randomly
placed into different groups based on the volume of the tumor (five
mice in each group).
[0269] The mice were then injected with physiological saline as a
control (G1), humanized anti-PD-1 antibody 1A7-H1K3-IgG4-S228P
(G2), humanized anti-PD-1 antibody 1A7-H2K3-IgG4-S228P (G3), or
Keytruda (G4). The antibodies were given on the second day and the
fifth day of each week by intraperitoneal injection at 1 mg/kg for
3 weeks (6 injections in total).
[0270] The weight of the mice was monitored during the entire
treatment period. The weight of mice in different groups all
increased (FIG. 13, and FIG. 14). No significant difference in
weight was observed among the different groups. The results showed
that the anti-hPD-1 antibodies were well tolerated and not toxic to
the mice.
[0271] The tumor size showed significant difference in groups
treated with the anti-hPD-1 antibodies (FIG. 15). Particularly, the
tumor size in G2 is smaller than G4; and the tumor size in G3 is
smaller than G4.
[0272] The TGI % at Day 21 (21 days after grouping) for each
treatment group was also calculated as shown in the table
below.
TABLE-US-00006 TABLE 6 Average tumor size at Group Antibodies Day
18 TGI % P value G1 PS 1986 -- -- G2 1A7-H1K3-IgG4-S228P 233 94.5%
0.001 (1 mg/kg) G3 1A7-H2K3-IgG4-S228P 150 99.0% 0.001 (1 mg/kg) G4
Keytruda 422 84.4% 0.006 (1 mg/kg)
[0273] The results above show that all the anti-hPD-1 antibodies
can inhibit tumor growth. Among them, 1A7-H2K3-IgG4-S228P (1 mg/kg)
had the highest tumor growth inhibition percentage (TGI %).
OTHER EMBODIMENTS
[0274] It is to be understood that while the invention has been
described in conjunction with the detailed description thereof, the
foregoing description is intended to illustrate and not limit the
scope of the invention, which is defined by the scope of the
appended claims. Other aspects, advantages, and modifications are
within the scope of the following claims.
Sequence CWU 1
1
4415PRTArtificial SequenceCDR sequence 1Ser Tyr Ser Met Ser1
5217PRTArtificial SequenceCDR sequence 2His Ile Ser Ser Gly Gly Ser
Ser Thr Tyr Tyr Pro Asp Thr Val Lys1 5 10 15Gly313PRTArtificial
SequenceCDR sequence 3Gln Phe Tyr Tyr Gly Ser Ser Phe Trp Tyr Phe
Asp Val1 5 10415PRTArtificial SequenceCDR sequence 4Lys Ala Ser Gln
Ser Val Asp Phe Asp Gly Asp Ser Tyr Met Asn1 5 10 1557PRTArtificial
SequenceCDR sequence 5Ala Ala Ser Asn Leu Glu Ser1 569PRTArtificial
SequenceCDR sequence 6Gln Gln Ser Asn Glu Asp Pro Pro Thr1
575PRTArtificial SequenceCDR sequence 7Ser Tyr Trp Met His1
5817PRTArtificial SequenceCDR sequence 8Tyr Ile Asn Pro Ser Thr Gly
Tyr Thr Glu Tyr Asn Gln Lys Phe Lys1 5 10 15Asp98PRTArtificial
SequenceCDR sequence 9Gly Val Arg Tyr Tyr Phe Asp Tyr1
51017PRTArtificial SequenceCDR sequence 10Lys Ser Ser Gln Ser Leu
Leu Asn Ser Arg Thr Arg Lys Asn Tyr Leu1 5 10 15Ala117PRTArtificial
SequenceCDR sequence 11Trp Ala Ser Thr Arg Glu Ser1
5128PRTArtificial SequenceCDR sequence 12Lys Gln Ser Tyr Asn Leu
Leu Thr1 51317PRTArtificial SequenceCDR sequence 13Tyr Ile Asn Pro
Asn Thr Gly Tyr Thr Glu Tyr Asn Gln Lys Phe Lys1 5 10
15Asp148PRTArtificial SequenceCDR sequence 14Gly Thr Ala Tyr Tyr
Phe Asp Tyr1 5158PRTArtificial SequenceCDR sequence 15Lys Gln Ser
Tyr Asn Leu Gln Thr1 51610PRTArtificial SequenceCDR sequence 16Gly
Phe Thr Phe Ser Ser Tyr Ser Met Ser1 5 10176PRTArtificial
SequenceCDR sequence 17Ser Ser Gly Gly Ser Ser1 51810PRTArtificial
SequenceCDR sequence 18Gly Tyr Thr Phe Thr Ser Tyr Trp Met His1 5
10196PRTArtificial SequenceCDR sequence 19Asn Pro Ser Thr Gly Tyr1
52010PRTArtificial SequenceCDR sequence 20Gly Tyr Thr Leu Thr Ser
Tyr Trp Met His1 5 10216PRTArtificial SequenceCDR sequence 21Asn
Pro Asn Thr Gly Tyr1 522288PRTHomo sapiens 22Met Gln Ile Pro Gln
Ala Pro Trp Pro Val Val Trp Ala Val Leu Gln1 5 10 15Leu Gly Trp Arg
Pro Gly Trp Phe Leu Asp Ser Pro Asp Arg Pro Trp 20 25 30Asn Pro Pro
Thr Phe Ser Pro Ala Leu Leu Val Val Thr Glu Gly Asp 35 40 45Asn Ala
Thr Phe Thr Cys Ser Phe Ser Asn Thr Ser Glu Ser Phe Val 50 55 60Leu
Asn Trp Tyr Arg Met Ser Pro Ser Asn Gln Thr Asp Lys Leu Ala65 70 75
80Ala Phe Pro Glu Asp Arg Ser Gln Pro Gly Gln Asp Cys Arg Phe Arg
85 90 95Val Thr Gln Leu Pro Asn Gly Arg Asp Phe His Met Ser Val Val
Arg 100 105 110Ala Arg Arg Asn Asp Ser Gly Thr Tyr Leu Cys Gly Ala
Ile Ser Leu 115 120 125Ala Pro Lys Ala Gln Ile Lys Glu Ser Leu Arg
Ala Glu Leu Arg Val 130 135 140Thr Glu Arg Arg Ala Glu Val Pro Thr
Ala His Pro Ser Pro Ser Pro145 150 155 160Arg Pro Ala Gly Gln Phe
Gln Thr Leu Val Val Gly Val Val Gly Gly 165 170 175Leu Leu Gly Ser
Leu Val Leu Leu Val Trp Val Leu Ala Val Ile Cys 180 185 190Ser Arg
Ala Ala Arg Gly Thr Ile Gly Ala Arg Arg Thr Gly Gln Pro 195 200
205Leu Lys Glu Asp Pro Ser Ala Val Pro Val Phe Ser Val Asp Tyr Gly
210 215 220Glu Leu Asp Phe Gln Trp Arg Glu Lys Thr Pro Glu Pro Pro
Val Pro225 230 235 240Cys Val Pro Glu Gln Thr Glu Tyr Ala Thr Ile
Val Phe Pro Ser Gly 245 250 255Met Gly Thr Ser Ser Pro Ala Arg Arg
Gly Ser Ala Asp Gly Pro Arg 260 265 270Ser Ala Gln Pro Leu Arg Pro
Glu Asp Gly His Cys Ser Trp Pro Leu 275 280 28523288PRTMus musculus
23Met Trp Val Arg Gln Val Pro Trp Ser Phe Thr Trp Ala Val Leu Gln1
5 10 15Leu Ser Trp Gln Ser Gly Trp Leu Leu Glu Val Pro Asn Gly Pro
Trp 20 25 30Arg Ser Leu Thr Phe Tyr Pro Ala Trp Leu Thr Val Ser Glu
Gly Ala 35 40 45Asn Ala Thr Phe Thr Cys Ser Leu Ser Asn Trp Ser Glu
Asp Leu Met 50 55 60Leu Asn Trp Asn Arg Leu Ser Pro Ser Asn Gln Thr
Glu Lys Gln Ala65 70 75 80Ala Phe Cys Asn Gly Leu Ser Gln Pro Val
Gln Asp Ala Arg Phe Gln 85 90 95Ile Ile Gln Leu Pro Asn Arg His Asp
Phe His Met Asn Ile Leu Asp 100 105 110Thr Arg Arg Asn Asp Ser Gly
Ile Tyr Leu Cys Gly Ala Ile Ser Leu 115 120 125His Pro Lys Ala Lys
Ile Glu Glu Ser Pro Gly Ala Glu Leu Val Val 130 135 140Thr Glu Arg
Ile Leu Glu Thr Ser Thr Arg Tyr Pro Ser Pro Ser Pro145 150 155
160Lys Pro Glu Gly Arg Phe Gln Gly Met Val Ile Gly Ile Met Ser Ala
165 170 175Leu Val Gly Ile Pro Val Leu Leu Leu Leu Ala Trp Ala Leu
Ala Val 180 185 190Phe Cys Ser Thr Ser Met Ser Glu Ala Arg Gly Ala
Gly Ser Lys Asp 195 200 205Asp Thr Leu Lys Glu Glu Pro Ser Ala Ala
Pro Val Pro Ser Val Ala 210 215 220Tyr Glu Glu Leu Asp Phe Gln Gly
Arg Glu Lys Thr Pro Glu Leu Pro225 230 235 240Thr Ala Cys Val His
Thr Glu Tyr Ala Thr Ile Val Phe Thr Glu Gly 245 250 255Leu Gly Ala
Ser Ala Met Gly Arg Arg Gly Ser Ala Asp Gly Leu Gln 260 265 270Gly
Pro Arg Pro Pro Arg His Glu Asp Gly His Cys Ser Trp Pro Leu 275 280
28524288PRTRhesus macaque 24Met Gln Ile Pro Gln Ala Pro Trp Pro Val
Val Trp Ala Val Leu Gln1 5 10 15Leu Gly Trp Arg Pro Gly Trp Phe Leu
Glu Ser Pro Asp Arg Pro Trp 20 25 30Asn Pro Pro Thr Phe Ser Pro Ala
Leu Leu Leu Val Thr Glu Gly Asp 35 40 45Asn Ala Thr Phe Thr Cys Ser
Phe Ser Asn Ala Ser Glu Ser Phe Val 50 55 60Leu Asn Trp Tyr Arg Met
Ser Pro Ser Asn Gln Thr Asp Lys Leu Ala65 70 75 80Ala Phe Pro Glu
Asp Arg Ser Gln Pro Gly Arg Asp Cys Arg Phe Arg 85 90 95Val Thr Gln
Leu Pro Asn Gly Arg Asp Phe His Met Ser Val Val Arg 100 105 110Ala
Arg Arg Asn Asp Ser Gly Thr Tyr Leu Cys Gly Ala Ile Ser Leu 115 120
125Ala Pro Lys Ala Gln Ile Lys Glu Ser Leu Arg Ala Glu Leu Arg Val
130 135 140Thr Glu Arg Arg Ala Glu Val Pro Thr Ala His Pro Ser Pro
Ser Pro145 150 155 160Arg Pro Ala Gly Gln Phe Gln Ala Leu Val Val
Gly Val Val Gly Gly 165 170 175Leu Leu Gly Ser Leu Val Leu Leu Val
Trp Val Leu Ala Val Ile Cys 180 185 190Ser Arg Ala Ala Gln Gly Thr
Ile Glu Ala Arg Arg Thr Gly Gln Pro 195 200 205Leu Lys Glu Asp Pro
Ser Ala Val Pro Val Phe Ser Val Asp Tyr Gly 210 215 220Glu Leu Asp
Phe Gln Trp Arg Glu Lys Thr Pro Glu Pro Pro Ala Pro225 230 235
240Cys Val Pro Glu Gln Thr Glu Tyr Ala Thr Ile Val Phe Pro Ser Gly
245 250 255Leu Gly Thr Ser Ser Pro Ala Arg Arg Gly Ser Ala Asp Gly
Pro Arg 260 265 270Ser Pro Arg Pro Leu Arg Pro Glu Asp Gly His Cys
Ser Trp Pro Leu 275 280 28525288PRTArtificial SequenceChimeric PD-1
25Met Trp Val Arg Gln Val Pro Trp Ser Phe Thr Trp Ala Val Leu Gln1
5 10 15Leu Ser Trp Gln Ser Gly Trp Leu Leu Glu Val Pro Asn Gly Pro
Trp 20 25 30Asn Pro Pro Thr Phe Ser Pro Ala Leu Leu Val Val Thr Glu
Gly Asp 35 40 45Asn Ala Thr Phe Thr Cys Ser Phe Ser Asn Thr Ser Glu
Ser Phe Val 50 55 60Leu Asn Trp Tyr Arg Met Ser Pro Ser Asn Gln Thr
Asp Lys Leu Ala65 70 75 80Ala Phe Pro Glu Asp Arg Ser Gln Pro Gly
Gln Asp Cys Arg Phe Arg 85 90 95Val Thr Gln Leu Pro Asn Gly Arg Asp
Phe His Met Ser Val Val Arg 100 105 110Ala Arg Arg Asn Asp Ser Gly
Thr Tyr Leu Cys Gly Ala Ile Ser Leu 115 120 125Ala Pro Lys Ala Gln
Ile Lys Glu Ser Leu Arg Ala Glu Leu Val Val 130 135 140Thr Glu Arg
Ile Leu Glu Thr Ser Thr Arg Tyr Pro Ser Pro Ser Pro145 150 155
160Lys Pro Glu Gly Arg Phe Gln Gly Met Val Ile Gly Ile Met Ser Ala
165 170 175Leu Val Gly Ile Pro Val Leu Leu Leu Leu Ala Trp Ala Leu
Ala Val 180 185 190Phe Cys Ser Thr Ser Met Ser Glu Ala Arg Gly Ala
Gly Ser Lys Asp 195 200 205Asp Thr Leu Lys Glu Glu Pro Ser Ala Ala
Pro Val Pro Ser Val Ala 210 215 220Tyr Glu Glu Leu Asp Phe Gln Gly
Arg Glu Lys Thr Pro Glu Leu Pro225 230 235 240Thr Ala Cys Val His
Thr Glu Tyr Ala Thr Ile Val Phe Thr Glu Gly 245 250 255Leu Gly Ala
Ser Ala Met Gly Arg Arg Gly Ser Ala Asp Gly Leu Gln 260 265 270Gly
Pro Arg Pro Pro Arg His Glu Asp Gly His Cys Ser Trp Pro Leu 275 280
28526122PRTArtificial SequenceVH 26Glu Val Gln Leu Leu Glu Ser Gly
Gly Gly Leu Val Gln Pro Gly Gly1 5 10 15Ser Leu Arg Leu Ser Cys Ala
Ala Ser Gly Phe Thr Phe Ser Ser Tyr 20 25 30Ser Met Ser Trp Val Arg
Gln Ala Pro Gly Lys Arg Leu Glu Trp Val 35 40 45Ala His Ile Ser Ser
Gly Gly Ser Ser Thr Tyr Tyr Pro Asp Thr Val 50 55 60Lys Gly Arg Phe
Thr Ile Ser Arg Asp Asn Ser Lys Asn Thr Leu Tyr65 70 75 80Leu Gln
Met Asn Ser Leu Arg Ala Glu Asp Thr Ala Met Tyr Tyr Cys 85 90 95Thr
Arg Gln Phe Tyr Tyr Gly Ser Ser Phe Trp Tyr Phe Asp Val Trp 100 105
110Gly Gln Gly Thr Thr Val Thr Val Ser Ser 115
12027122PRTArtificial SequenceVH 27Glu Val Gln Leu Val Glu Ser Gly
Gly Gly Leu Val Gln Pro Gly Gly1 5 10 15Ser Leu Arg Leu Ser Cys Ala
Ala Ser Gly Phe Thr Phe Ser Ser Tyr 20 25 30Ser Met Ser Trp Val Arg
Gln Ala Pro Gly Lys Arg Leu Glu Trp Val 35 40 45Ala His Ile Ser Ser
Gly Gly Ser Ser Thr Tyr Tyr Pro Asp Thr Val 50 55 60Lys Gly Arg Phe
Thr Ile Ser Arg Asp Asn Ser Lys Asn Thr Leu Tyr65 70 75 80Leu Gln
Met Asn Ser Leu Arg Ala Glu Asp Thr Ala Met Tyr Tyr Cys 85 90 95Thr
Arg Gln Phe Tyr Tyr Gly Ser Ser Phe Trp Tyr Phe Asp Val Trp 100 105
110Gly Ala Gly Thr Thr Val Thr Val Ser Ser 115
12028122PRTArtificial SequenceVH 28Glu Val Lys Leu Val Glu Ser Gly
Gly Gly Leu Val Gln Pro Gly Gly1 5 10 15Ser Leu Arg Leu Ser Cys Ala
Ala Ser Gly Phe Thr Phe Ser Ser Tyr 20 25 30Ser Met Ser Trp Val Arg
Gln Ala Pro Gly Lys Arg Leu Glu Trp Val 35 40 45Ala His Ile Ser Ser
Gly Gly Ser Ser Thr Tyr Tyr Pro Asp Thr Val 50 55 60Lys Gly Arg Phe
Thr Ile Ser Arg Asp Asn Ser Lys Asn Thr Leu Tyr65 70 75 80Leu Gln
Met Asn Ser Leu Arg Ala Glu Asp Thr Ala Met Tyr Tyr Cys 85 90 95Thr
Arg Gln Phe Tyr Tyr Gly Ser Ser Phe Trp Tyr Phe Asp Val Trp 100 105
110Gly Ala Gly Thr Thr Val Thr Val Ser Ser 115
12029111PRTArtificial SequenceVL 29Asp Asn Val Leu Thr Gln Ser Pro
Ala Thr Leu Ser Leu Ser Pro Gly1 5 10 15Glu Arg Ala Thr Leu Ser Cys
Lys Ala Ser Gln Ser Val Asp Phe Asp 20 25 30Gly Asp Ser Tyr Met Asn
Trp Tyr Gln Gln Lys Pro Gly Gln Pro Pro 35 40 45Arg Leu Leu Ile Tyr
Ala Ala Ser Asn Leu Glu Ser Gly Ile Pro Ala 50 55 60Arg Phe Ser Gly
Ser Gly Pro Gly Thr Asp Phe Thr Leu Thr Ile Ser65 70 75 80Ser Leu
Glu Pro Glu Asp Phe Ala Thr Tyr Tyr Cys Gln Gln Ser Asn 85 90 95Glu
Asp Pro Pro Thr Phe Gly Gly Gly Thr Lys Val Glu Ile Lys 100 105
11030111PRTArtificial SequenceVL 30Asp Asn Val Leu Thr Gln Ser Pro
Ala Thr Leu Ser Val Ser Pro Gly1 5 10 15Glu Arg Ala Thr Leu Ser Cys
Lys Ala Ser Gln Ser Val Asp Phe Asp 20 25 30Gly Asp Ser Tyr Met Asn
Trp Tyr Gln Gln Lys Pro Gly Gln Pro Pro 35 40 45Arg Leu Leu Ile Tyr
Ala Ala Ser Asn Leu Glu Ser Gly Ile Pro Ala 50 55 60Arg Phe Ser Gly
Ser Gly Pro Gly Thr Asp Phe Thr Leu Thr Ile Ser65 70 75 80Ser Leu
Glu Pro Glu Asp Phe Ala Thr Tyr Tyr Cys Gln Gln Ser Asn 85 90 95Glu
Asp Pro Pro Thr Phe Gly Gly Gly Thr Lys Val Glu Ile Lys 100 105
11031111PRTArtificial SequenceVL 31Asp Asn Val Leu Thr Gln Ser Pro
Ala Thr Leu Ser Val Ser Pro Gly1 5 10 15Glu Arg Ala Thr Leu Ser Cys
Lys Ala Ser Gln Ser Val Asp Phe Asp 20 25 30Gly Asp Ser Tyr Met Asn
Trp Tyr Gln Gln Lys Pro Gly Gln Pro Pro 35 40 45Arg Leu Leu Ile Tyr
Ala Ala Ser Asn Leu Glu Ser Gly Ile Pro Ala 50 55 60Arg Phe Ser Gly
Ser Gly Ser Gly Thr Asp Phe Thr Leu Thr Ile Ser65 70 75 80Ser Val
Glu Pro Glu Asp Phe Ala Thr Tyr Tyr Cys Gln Gln Ser Asn 85 90 95Glu
Asp Pro Pro Thr Phe Gly Gly Gly Thr Lys Val Glu Ile Lys 100 105
11032117PRTArtificial SequenceVH 32Gln Val Gln Leu Gln Gln Ser Gly
Ala Glu Val Lys Lys Pro Gly Ala1 5 10 15Ser Val Lys Met Ser Cys Lys
Ala Ser Gly Tyr Thr Phe Thr Ser Tyr 20 25 30Trp Met His Trp Val Arg
Gln Ala Pro Gly Gln Gly Leu Glu Trp Ile 35 40 45Gly Tyr Ile Asn Pro
Ser Thr Gly Tyr Thr Glu Tyr Asn Gln Lys Phe 50 55 60Lys Asp Arg Ala
Thr Leu Thr Ala Asp Thr Ser Thr Ser Thr Ala Tyr65 70 75 80Met Glu
Leu Ser Ser Leu Arg Ser Glu Asp Thr Ala Val Tyr Tyr Cys 85 90 95Ala
Arg Gly Val Arg Tyr Tyr Phe Asp Tyr Trp Gly Gln Gly Thr Leu 100 105
110Val Thr Val Ser Ser 11533117PRTArtificial SequenceVH 33Gln Val
Gln Leu Gln Gln Ser Gly Ala Glu Val Lys Lys Pro Gly Ala1 5 10 15Ser
Val Lys Met Ser Cys Lys Ala Ser Gly Tyr Thr Phe Thr Ser Tyr 20 25
30Trp Met His Trp Val Lys Gln Arg Pro Gly Gln Gly Leu Glu Trp Ile
35 40 45Gly Tyr Ile Asn Pro Ser Thr Gly Tyr Thr Glu Tyr Asn Gln Lys
Phe 50 55 60Lys Asp Arg Ala Thr Leu Thr Ala Asp Lys Ser Thr Ser Thr
Ala Tyr65 70 75 80Met Glu Leu Ser Ser Leu Arg Ser Glu Asp Thr Ala
Val Tyr Tyr Cys 85 90 95Ala Arg Gly Val Arg Tyr Tyr Phe Asp Tyr Trp
Gly Gln Gly Thr Leu 100 105 110Val Thr Val Ser Ser
11534117PRTArtificial SequenceVH 34Gln Val Gln Leu Gln Gln Ser Gly
Ala Glu Val Ala Lys Pro Gly Ala1 5
10 15Ser Val Lys Met Ser Cys Lys Ala Ser Gly Tyr Thr Phe Thr Ser
Tyr 20 25 30Trp Met His Trp Val Lys Gln Arg Pro Gly Gln Gly Leu Glu
Trp Ile 35 40 45Gly Tyr Ile Asn Pro Ser Thr Gly Tyr Thr Glu Tyr Asn
Gln Lys Phe 50 55 60Lys Asp Arg Ala Thr Leu Thr Ala Asp Thr Ser Thr
Ser Thr Ala Tyr65 70 75 80Met Glu Leu Ser Ser Leu Arg Ser Glu Asp
Thr Ala Val Tyr Tyr Cys 85 90 95Ala Arg Gly Val Arg Tyr Tyr Phe Asp
Tyr Trp Gly Gln Gly Thr Leu 100 105 110Leu Thr Val Ser Ser
11535117PRTArtificial SequenceVH 35Gln Val Gln Leu Gln Gln Ser Gly
Ala Glu Val Ala Lys Pro Gly Ala1 5 10 15Ser Val Lys Met Ser Cys Lys
Ala Ser Gly Tyr Thr Phe Thr Ser Tyr 20 25 30Trp Met His Trp Val Lys
Gln Arg Pro Gly Gln Gly Leu Glu Trp Ile 35 40 45Gly Tyr Ile Asn Pro
Ser Thr Gly Tyr Thr Glu Tyr Asn Gln Lys Phe 50 55 60Lys Asp Arg Ala
Thr Leu Thr Ala Asp Lys Ser Thr Ser Thr Ala Tyr65 70 75 80Met Glu
Leu Ser Ser Leu Thr Ser Glu Asp Thr Ala Val Tyr Tyr Cys 85 90 95Ala
Arg Gly Val Arg Tyr Tyr Phe Asp Tyr Trp Gly Gln Gly Thr Leu 100 105
110Leu Thr Val Ser Ser 11536112PRTArtificial SequenceVL 36Asp Ile
Val Met Thr Gln Ser Pro Asp Ser Leu Ala Val Ser Leu Gly1 5 10 15Glu
Arg Ala Thr Ile Ser Cys Lys Ser Ser Gln Ser Leu Leu Asn Ser 20 25
30Arg Thr Arg Lys Asn Tyr Leu Ala Trp Tyr Gln Gln Lys Pro Gly Gln
35 40 45Ser Pro Lys Leu Leu Ile Tyr Trp Ala Ser Thr Arg Glu Ser Gly
Val 50 55 60Pro Asp Arg Phe Ser Gly Ser Gly Ser Gly Thr Asp Phe Thr
Leu Thr65 70 75 80Ile Ser Ser Val Gln Ala Glu Asp Val Ala Val Tyr
Tyr Cys Lys Gln 85 90 95Ser Tyr Asn Leu Leu Thr Phe Gly Gln Gly Thr
Lys Leu Glu Leu Lys 100 105 11037112PRTArtificial SequenceVL 37Asp
Ile Val Met Thr Gln Ser Pro Asp Ser Leu Ala Val Ser Leu Gly1 5 10
15Glu Arg Ala Thr Met Ser Cys Lys Ser Ser Gln Ser Leu Leu Asn Ser
20 25 30Arg Thr Arg Lys Asn Tyr Leu Ala Trp Tyr Gln Gln Lys Pro Gly
Gln 35 40 45Ser Pro Lys Leu Leu Ile Tyr Trp Ala Ser Thr Arg Glu Ser
Gly Val 50 55 60Pro Asp Arg Phe Ser Gly Ser Gly Ser Gly Thr Asp Phe
Thr Leu Thr65 70 75 80Ile Ser Ser Val Gln Ala Glu Asp Val Ala Val
Tyr Tyr Cys Lys Gln 85 90 95Ser Tyr Asn Leu Leu Thr Phe Gly Gln Gly
Thr Lys Leu Glu Leu Lys 100 105 11038112PRTArtificial SequenceVL
38Asp Ile Val Met Thr Gln Ser Pro Ser Ser Leu Ala Val Ser Ala Gly1
5 10 15Glu Arg Val Thr Met Ser Cys Lys Ser Ser Gln Ser Leu Leu Asn
Ser 20 25 30Arg Thr Arg Lys Asn Tyr Leu Ala Trp Tyr Gln Gln Lys Pro
Gly Gln 35 40 45Ser Pro Lys Leu Leu Ile Tyr Trp Ala Ser Thr Arg Glu
Ser Gly Val 50 55 60Pro Asp Arg Phe Ser Gly Ser Gly Ser Gly Thr Asp
Phe Thr Leu Thr65 70 75 80Ile Ser Ser Val Gln Ala Glu Asp Val Ala
Val Tyr Tyr Cys Lys Gln 85 90 95Ser Tyr Asn Leu Leu Thr Phe Gly Gln
Gly Thr Lys Leu Glu Leu Lys 100 105 11039122PRTMus musculus 39Glu
Val Lys Leu Val Glu Ser Gly Gly Gly Leu Val Gln Pro Gly Gly1 5 10
15Ser Leu Lys Leu Ser Cys Ala Ala Ser Gly Phe Thr Phe Ser Ser Tyr
20 25 30Ser Met Ser Trp Val Arg Gln Thr Pro Glu Lys Arg Leu Glu Trp
Val 35 40 45Ala His Ile Ser Ser Gly Gly Ser Ser Thr Tyr Tyr Pro Asp
Thr Val 50 55 60Lys Gly Arg Phe Thr Ile Ser Arg Asp Asn Ala Arg Asn
Thr Leu Tyr65 70 75 80Leu Gln Met Ser Ser Leu Lys Ser Glu Asp Thr
Ala Met Tyr Tyr Cys 85 90 95Thr Arg Gln Phe Tyr Tyr Gly Ser Ser Phe
Trp Tyr Phe Asp Val Trp 100 105 110Gly Ala Gly Thr Thr Val Thr Val
Ser Ser 115 12040111PRTMus musculus 40Asp Asn Val Leu Thr Gln Ser
Pro Val Ser Leu Ala Val Ser Leu Gly1 5 10 15Gln Arg Ala Thr Ile Ser
Cys Lys Ala Ser Gln Ser Val Asp Phe Asp 20 25 30Gly Asp Ser Tyr Met
Asn Trp Tyr Gln Gln Lys Pro Gly Gln Pro Pro 35 40 45Lys Leu Leu Ile
Tyr Ala Ala Ser Asn Leu Glu Ser Gly Ile Pro Ala 50 55 60Arg Phe Ser
Gly Ser Gly Ser Gly Thr Asp Phe Thr Leu Asn Ile His65 70 75 80Pro
Val Glu Glu Glu Asp Ala Ala Thr Tyr Tyr Cys Gln Gln Ser Asn 85 90
95Glu Asp Pro Pro Thr Phe Gly Gly Gly Thr Lys Leu Glu Ile Lys 100
105 11041117PRTMus musculus 41Gln Val Gln Leu Gln Gln Ser Gly Ala
Glu Leu Ala Lys Pro Gly Ala1 5 10 15Ser Val Lys Met Ser Cys Lys Ala
Ser Gly Tyr Thr Phe Thr Ser Tyr 20 25 30Trp Met His Trp Val Lys Gln
Arg Pro Gly Gln Gly Leu Glu Trp Ile 35 40 45Gly Tyr Ile Asn Pro Ser
Thr Gly Tyr Thr Glu Tyr Asn Gln Lys Phe 50 55 60Lys Asp Lys Ala Thr
Leu Thr Ala Asp Lys Ser Ser Ser Thr Ala Tyr65 70 75 80Met Gln Leu
Ser Ser Leu Thr Ser Glu Asp Ser Ala Val Tyr Tyr Cys 85 90 95Ala Arg
Gly Val Arg Tyr Tyr Phe Asp Tyr Trp Gly Gln Gly Thr Thr 100 105
110Leu Thr Val Ser Ser 11542112PRTMus musculus 42Asp Ile Val Met
Ser Gln Ser Pro Ser Ser Leu Ala Val Ser Ala Gly1 5 10 15Glu Lys Val
Thr Met Ser Cys Lys Ser Ser Gln Ser Leu Leu Asn Ser 20 25 30Arg Thr
Arg Lys Asn Tyr Leu Ala Trp Tyr Gln Gln Lys Pro Gly Gln 35 40 45Ser
Pro Lys Leu Leu Ile Tyr Trp Ala Ser Thr Arg Glu Ser Gly Val 50 55
60Pro Asp Arg Phe Thr Gly Ser Gly Ser Gly Thr Asp Phe Thr Leu Thr65
70 75 80Ile Ser Ser Val Gln Ala Glu Asp Leu Ala Val Tyr Tyr Cys Lys
Gln 85 90 95Ser Tyr Asn Leu Leu Thr Phe Gly Ala Gly Thr Lys Leu Glu
Leu Lys 100 105 11043117PRTMus musculus 43Gln Val Gln Leu Gln Gln
Ser Gly Ala Glu Leu Ala Lys Pro Gly Ala1 5 10 15Ser Leu Lys Met Ser
Cys Lys Ala Ser Gly Tyr Thr Leu Thr Ser Tyr 20 25 30Trp Met His Trp
Val Lys Gln Arg Pro Gly Gln Gly Leu Glu Trp Ile 35 40 45Gly Tyr Ile
Asn Pro Asn Thr Gly Tyr Thr Glu Tyr Asn Gln Lys Phe 50 55 60Lys Asp
Lys Ala Thr Leu Thr Ala Asp Lys Ser Ser Ser Thr Ala Tyr65 70 75
80Met Gln Leu Ser Ser Leu Thr Ser Glu Asp Ser Ala Val Tyr Tyr Cys
85 90 95Ala Arg Gly Thr Ala Tyr Tyr Phe Asp Tyr Trp Gly Gln Gly Thr
Thr 100 105 110Leu Thr Val Ser Ser 11544112PRTMus musculus 44Asp
Ile Val Met Ser Gln Ser Pro Ser Ser Leu Ala Val Ser Ala Gly1 5 10
15Glu Lys Val Thr Met Ser Cys Lys Ser Ser Gln Ser Leu Leu Asn Ser
20 25 30Arg Thr Arg Lys Asn Tyr Leu Ala Trp Tyr Gln Gln Lys Pro Gly
Gln 35 40 45Ser Pro Lys Leu Leu Ile Tyr Trp Ala Ser Thr Arg Glu Ser
Gly Val 50 55 60Pro Asp Arg Phe Thr Gly Ser Gly Ser Gly Thr Asp Phe
Thr Leu Thr65 70 75 80Ile Ser Ser Val Gln Ala Glu Asp Leu Ala Val
Tyr Tyr Cys Lys Gln 85 90 95Ser Tyr Asn Leu Gln Thr Phe Gly Gly Gly
Thr Lys Leu Glu Ile Lys 100 105 110
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