Antibodies against amyloid-β peptide
Antibodies that bind human β-amyloid peptide, methods of treating diseases or disorders characterised by elevated β-amyloid levels or β-amyloid deposits with said antibodies, pharmaceutical compositions comprising said antibodies and methods of manufacture.
1. An isolated therapeutic antibody which is an antibody or antigen binding fragment which binds β-amyloid peptide and which comprises the following CDRs:
CDRH1: DNGMA (SEQ ID No:1)
CDRH2: FISNLAYSIDYADTVTG (SEQ ID No:2)
CDRH3: GTWFAY (SEQ ID No:3)
within a human heavy chain variable region originating from the VH3 gene family and:
CDRL1: RVSQSLLHSNGYTYLH (SEQ ID No:4)
CDRL2: KVSNRFS (SEQ ID No:5)
CDRL3: SQTRHVPYT (SEQ ID No:6)
within a human light chain variable region originating from the amino acid sequence disclosed in GenPept entry CAA51135 (SEQ ID No:24).
2. An isolated therapeutic antibody according to claim 1 , in which the human heavy chain variable region originates from a V gene selected from the group consisting of: VH3-48, VH3-21, VH3-11, VH3-7, VH3-13, VH3-74, VH3-64, VH3-23, VH3-38, VH3-53, VH3-66, VH3-20, VH3-9 and VH3-43.
3. An isolated therapeutic antibody according to claim 2 having a human acceptor heavy chain framework of M99675 (SEQ ID No:21) together with a framework 4.
4. An isolated therapeutic antibody according to claim 3 , in which the framework 4 sequence is that encoded by the human JH4 minigene (Kabat):
YFDYWGQGTLVTVSS (SEQ ID No:23)
of which the initial four residues fall within the CDR3 region is replaced by the incoming CDR from a donor antibody.
5. An isolated therapeutic antibody according to claim 1 which contains one or more substitutions of amino acid residues based on the corresponding residues found in a donor V H domain having the sequence: SEQ ID No:17 and V L domain having the sequence: SEQ ID No: 19 that maintain all or substantially all of the binding affinity of the donor antibody for β-amyloid peptide.
6. An isolated therapeutic antibody according to claim 5 having a human acceptor heavy chain framework of M99675 together with JH4 containing one to four amino acid residue substitutions selected from positions 24, 48, 93 and/or 94 (Kabat numbering).
7. An isolated therapeutic antibody according to claim 6 having a human acceptor heavy chain framework which comprises the following residues :
Position
Residue
(i)
93
V
94
S
or (ii)
24
V
93
V
94
S
or (iii)
48
I
93
V
94
S.
8. An isolated therapeutic antibody which binds β-amyloid peptide comprising a V H chain having the sequence set forth in SEQ ID No:26 and a V L domain having the sequence set forth in SEQ ID No:32.
9. An isolated therapeutic antibody which binds β-amyloid peptide comprising a V H chain having the sequence set forth in SEQ ID No: 28 and a V L domain having the sequence set forth in SEQ ID No:32.
10. An isolated therapeutic antibody which binds β-amyloid peptide comprising a V H chain having the sequence set forth in SEQ ID No:30 and a V L domain having the sequence set forth in SEQ ID No:32.
11. An isolated therapeutic antibody which is an antibody or antigen binding fragment which binds β-amyloid peptide 1-12 (SEQ ID No:15) with equilibrium constant KD less than 100 pM and has an equilibrium constant KD for binding to β-amyloid peptide 2-13 (SEQ ID No:44) which is 1000-fold greater than that for peptide 1-12 (SEQ ID No:15), both determinations being made in a surface plasmon resonance assay utilising peptide captured on streptavidin chip.
12. An isolated therapeutic antibody which is an antibody or antigen binding fragment which binds β-amyloid peptide 1-40 with equilibrium constant KD less than 10 nM and has an equilibrium constant KD for binding to β-amyloid peptide 2-13 (SEQ ID No:44) which is 1000-fold greater than that for peptide 1-12 (SEQ ID No:15), both determinations being made in the surface plasmon resonance assay described in Method B of the Examples.
13. An isolated therapeutic antibody according claim 1 which is of IgG1 isotype.
14. An isolated therapeutic antibody according to claim 1 which essentially lacks the functions of a) activation of complement by the classical pathway; and b) mediating antibody-dependent cellular cytotoxicity.
15. An isolated therapeutic antibody according to claim 13 in which residues 235 and 237 have been mutated to alanine.
16. An isolated therapeutic antibody according to claim 1 , which antibody comprises a heavy chain having the sequence set forth in SEQ ID No:34, 36 or 38 and a light chain having the sequence set forth in SEQ ID No:40.
17. A pharmaceutical composition comprising an isolated therapeutic antibody according to claim 1 .
18. An isolated antibody or a fragment thereof which binds β-amyloid peptide comprising a V H domain having the sequence: SEQ ID No:17 and a V L domain having the sequence: SEQ ID No: 19.