Hemophilia A

Hemophilia A is an X-linked bleeding disorder that occurs in approximately 1:5000 live male births worldwide and is characterized by a decrease in factor VIII (FVIII) activity level and elevated partial thromboplastin time. In general, the severity of bleeding is commensurate with the residual FVIII level. Bleeding manifestations include joint and muscle hemorrhage as well as postsurgical, oral, and soft tissue bleeding. The most common morbidity is chronic musculoskeletal damage from recurrent bleeding. Both plasma-derived and recombinant FVIII concentrates are available to prevent or treat bleeding. Dosing and frequency are determined by the desired plasma factor level, clinical response and product characteristics. Inhibitory antibodies to infused FVIII occur in 30% of patients with severe hemophilia in which case bypassing agents may be required for treatment. Since 2010, significant advances have been made in gene therapy, recombinant products with more favorable pharmacokinetic profiles, as well as novel nonfactor-based therapeutics.