The effect of repeated administration of mCTLA4-Ig on antifactor VIII antibody formation.

After the first injection, which contained both factor VIII and mCTLA4-Ig, hemophilia A mice were injected intravenously, at 3-week intervals, with both 1 μg factor VIII and 250 μg mCTLA4-Ig (•) or with factor VIII alone (○). Serum samples for the antifactor VIII assay were obtained 4 weeks after the sixth factor VIII injection.