A factor VIII–nanobody fusion protein forming an ultrastable complex with VWF: effect on clearance and antibody formation

= .0043). Unexpectedly, when examining anti-FVIII antibody formation in FVIII-deficient mice, the immune-response toward FVIII-KB013bv was significantly reduced compared with BDD-FVIII (1/8 vs 14/16 mice produced anti-FVIII antibodies after treatment with FVIII-KB013bv and BDD-FVIII, respectively). Our data show that a stabilized interaction between FVIII and VWF is associated with a prolonged survival of FVIII and a reduced immune response against FVIII.