Antibodies which bind and inhibit blood factor VIII
The present invention discloses inhibitory antibodies against Factor VIII with modified glycosylation, either by enzymatic deglycosylation or by site directed mutagenesis. Said antibodies with modified glycosylation have equal affinity for FVIII but show different inhibiting properties. The use of one or a mixture of said antibodies allow modulation of the inhibition of factor VIII to levels between 40 and 95%. The present invention further discloses pharmaceutical compositions comprising inhibitory antibodies against Factor VIII with modified glycosylation, combinations of these antibodies and methods for treating haemostasis disorders using said antibodies and antibody mixtures.
1. An isolated inhibitory antibody against factor VIII or a fragment thereof comprising the immunoglobulin variable light chain CDR1, CDR2, and CDR3 regions depicted in SEQ ID NO:36, SEQ ID NO:37, and SEQ ID NO:38 respectively, and comprising the immunoglobulin variable heavy chain CDR1, CDR2, and CDR3 regions depicted in SEQ ID NO:33, SEQ ID NO:34, and SEQ ID NO:35 respectively, wherein the glycosylation of said antibody or fragment thereof on the glycosylation site at amino acid positions 3 to 5 of the CDR1 region of the variable heavy chain is decreased relative to the glycosylation of the same antibody as produced by the EBV-immortalized human B cell line KRIX1 deposited with the Belgian Coordinated Collections of Micro-organisms under accession number LMBP 5089CB.
2. The isolated antibody according to claim 1 wherein said decreased glycosylation results from producing said antibody in CHO cells.
3. A pharmaceutical composition comprising the antibody according to claim 1 .