The U.S. Food and Drug Administration (FDA) has approved Pfizer’s HYMPAVZI (marstacimab-hncq) for routine prophylaxis to prevent or reduce the frequency of bleeding episodes in adults and pediatric patients 12 years of age and older with hemophilia A (congenital factor VIII deficiency) without factor VIII (FVIII) inhibitors, or hemophilia B (congenital factor IX deficiency) without factor IX (FIX) inhibitors.
HYMPAVZI is the first and only anti-tissue factor pathway inhibitor (anti-TFPI) approved in the U.S. for the treatment of hemophilia A or B and the first hemophilia medicine approved in the U.S. to be administered via a pre-filled, auto-injector pen. HYMPAVZI can offer a subcutaneous treatment option with a once-weekly dosing schedule and minimal preparation required for each individual administration.
“The approval of HYMPAVZI is a meaningful advancement for people living with hemophilia A or B without inhibitors for bleed prevention, with a generally manageable safety profile and a straightforward once-weekly subcutaneous administration,” said Suchitra S. Acharya, M.D., Director, Hemostasis and Thrombosis Center Northwell Health, Program Head, Bleeding Disorders and Thrombosis Program, Cohen Children’s Medical Center. “HYMPAVZI aims to reduce the current treatment burden by meeting an important need for these patients, including many who have required frequent, time-consuming intravenous treatment infusion regimens.”
Hemophilia is a family of rare genetic blood diseases caused by a clotting factor deficiency (FVIII in hemophilia A, FIX in hemophilia B), impacting more than 800,000 people globally. Diagnosed in early childhood, hemophilia inhibits the blood’s ability to clot properly, increasing the risk of repeated bleeding inside the joints, which can lead to permanent joint damage. Despite significant progress in hemophilia treatment in recent years, many people living with the disease continue to experience bleeding episodes and manage their condition with frequent intravenous infusions that may need to be administered multiple times a week.
“HYMPAVZI is Pfizer’s second hemophilia treatment to receive FDA approval this year and is the latest meaningful scientific advancement in our more than 40-year commitment to improve care for people living with hemophilia,” said Aamir Malik, Chief U.S. Commercial Officer and Executive Vice President, Pfizer. “We look forward to launching this latest medical breakthrough and to now offer three distinct classes of hemophilia medicines – an anti-TFPI, gene therapy, and recombinant factor treatments – that can meet the unique treatment needs of a wide range of patients.”
Results from the Phase 3 BASIS trial supported the approval of HYMPAVZI in the U.S. in adults and adolescents with hemophilia A or B without inhibitors. In the study, HYMPAVZI reduced the annualized bleeding rate (ABR) for treated bleeds by 35% and 92% after a 12-month active treatment period compared to routine prophylaxis (RP) and on-demand (OD) treatment, respectively, in patients with hemophilia A or B without inhibitors. The safety profile for HYMPAVZI was consistent with Phase 1/2 results. The most commonly reported adverse reactions (≥3% of patients) in the study were injection site reactions, headache, and pruritus.
“The hemophilia community continually seeks advancements in care that can improve quality of life for our community members,” said Phil Gattone, President and CEO, National Bleeding Disorders Foundation. “We greatly appreciate Pfizer’s innovative efforts in developing this novel treatment option that addresses some of the ongoing challenges faced by people with hemophilia A and B. The availability of this therapy represents a powerful step forward in advancing care for more individuals and families in the bleeding disorders community.”
The Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion for marstacimab for the routine prophylaxis of bleeding episodes in adults and adolescents 12 years and older with severe hemophilia A without FVIII inhibitors, or severe hemophilia B without FIX inhibitors. In addition to HYMPAVZI, Pfizer recently received regulatory approvals for its hemophilia B gene therapy BEQVEZ (fidanacogene elaparvovec) in the U.S., EU, and Canada, and announced positive results from a Phase 3 program investigating its hemophilia A gene therapy (giroctocogene fitelparvovec).
