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.