Hemophilia A is a bleeding disorder caused by genetic mutations that result in absent or dysfunctional Factor VIII (“FVIII”), leading to inadequate clotting of the blood in response to any type of injury or surgery. Prophylactic treatment consists of regular intravenous FVIII infusions. Unfortunately, due to loss of tolerance by the immune system to FVIII, 1/4 to 1/3 of patients develop neutralizing anti-FVIII antibodies referred to clinically as “Factor VIII Inhibitors”. These inhibitors decrease the efficacy of FVIII and render the treatment ineffective, resulting in a serious bleeding diathesis. The management of patients with these inhibitors is complex and frequently requires increase in dose or dose frequency of factor VIII which increase the cost of therapy for these patients and the heath economic burden. Inhibitor development in non-Hemophilia A individuals also occurs as a rare but serious autoimmune reaction that is typically diagnosed subsequent to unexplained bleeding, primarily in the elderly, or following trauma, surgery or childbirth (Lacroix-Desmazes S et al., 2020). Currently, there are few therapies available to help Factor VIII Inhibitor patients.
WP1301 is a peptide derived from hFVIII with modifications to improve solubility which are capable of binding to an MHC class II molecule without further antigen processing and being recognized by a factor VIII specific T cell. WP1301 offers a potential first-in-class approach for both the treatment and prevention of Factor VIII Intolerance. WP1301 is ready to start clinical trials and get an approved clinical protocol by MHRA.