FDA Approves Marstacimab-hncq (Hympavzi) for Hemophilia A or B Without Inhibitors

The FDA has approved Pfizer’s marstacimab-hncq, to be marketed under the name Hympavzi, for the treatment of adults and pediatric patients 12 years of age and older with hemophilia A without factor VIII (FVIII) inhibitors, or hemophilia B without factor IX (FIX) inhibitors.¹

“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,” Suchitra S. Acharya, MD, Director, Hemostasis and Thrombosis Center Northwell Health, Program Head, Bleeding Disorders and Thrombosis Program, Cohen Children’s Medical Center, said in a statement.¹ “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.”

Marstacimab is the first and only FDA-approved anti-tissue factor pathway inhibitor (anti-TFPI) for the treatment of hemophilia, and the first FDA-approved hemophilia medicine to be administered via a pre-filled, auto-injector pen. Marstacimab is a subcutaneous, once-weekly treatment. The FDA previously accepted Pfizer’s biologics license application for marstacimab, concomitantly with the European Medicines Agency (EMA)’s acceptance of a regulatory submission, in December 2023.² The drug is still up for approval by the EMA.

The approval was based off of data from the Phase 3 BASIS trial (NCT03938792), data from which were presented at the 2023 American Society of Hematology (ASH) Annual Meeting. The findings demonstrated that marstacimab 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 in the indicated populations. The drug’s safety profile continued to be manageable and commonly reported adverse reactions included injection site reactions, headache, and pruritus.³

“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,” Aamir Malik, Chief U.S. Commercial Officer and Executive Vice President, Pfizer, added.¹ “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.”

REFERENCES

1. U.S. FDA Approves Pfizer’s HYMPAVZI™ (marstacimab-hncq) for the Treatment of Adults and Adolescents with Hemophilia A or B Without Inhibitors. News release. Pfizer. October 11, 2024. https://www.businesswire.com/news/home/20241009505480/en/U.S.-FDA-Approves-Pfizer%E2%80%99s-HYMPAVZI%E2%84%A2-marstacimab-hncq-for-the-Treatment-of-Adults-and-Adolescents-with-Hemophilia-A-or-B-Without-Inhibitors

2. FDA and EMA Accept Marstacimab Regulatory Submissions for the Treatment of Hemophilia A and B. Pfizer.; 2023. Available at: https://www.pfizer.com/news/press-release/press-release-detail/fda-and-ema-accept-marstacimab-regulatory-submissions.

3. Marstacimab Phase 3 Data Presented at ASH 2023 Demonstrate Significant Bleed Reduction in Hemophilia A and B.; 2023. Available at: https://www.pfizer.com/news/press-release/press-release-detail/marstacimab-phase-3-data-presented-ash-2023-demonstrate.