FDA Greenlights Pfizer’s HYMPAVZI for Haemophilia Treatment

Pfizer has received approval from the US Food and Drug Administration (FDA) for its new drug, HYMPAVZI (marstacimab-hncq), designed for the routine prophylaxis of haemophilia A and B in patients. This medication, which functions as a rebalancing agent, targets the tissue factor pathway inhibitor’s (TFPI) Kunitz 2 domain. It offers a weekly subcutaneous treatment that plays a crucial role in preventing blood clot formation and restoring haemostasis by utilizing TFPI, a natural anticoagulant protein.

The introduction of HYMPAVZI marks a significant milestone as it is the first anti-TFPI approved in the United States. This new therapy is especially notable for its ability to be administered through a pre-filled auto-injector pen, which simplifies the treatment process for patients. The drug is approved for individuals aged 12 years and older, providing a new option that reduces the frequency and severity of bleeding episodes in patients with haemophilia A and B who do not have inhibitors.

Aamir Malik, Pfizer’s executive vice-president and US chief commercial officer, highlighted the company's ongoing dedication to advancing treatments for haemophilia. He noted that HYMPAVZI is the second haemophilia treatment from Pfizer to gain FDA approval within the year, underscoring the company's commitment to enhancing patient care. Malik emphasized the importance of offering diverse treatment options, including anti-TFPI, gene therapy, and recombinant factor treatments, to address the varied needs of haemophilia patients.

The FDA approval of HYMPAVZI was based on the results from the Phase III BASIS clinical trial. This pivotal study demonstrated a significant reduction in the annualized bleeding rate for patients receiving the treatment. Specifically, the trial reported a 35% decrease in bleeding episodes compared to routine prophylaxis and a 92% reduction compared to on-demand treatment after a 12-month period. These findings highlight the effectiveness of HYMPAVZI in managing bleeding episodes in patients with haemophilia.

In addition to the FDA approval, the European Medicines Agency’s (EMA) Committee for Medicinal Products for Human Use (CHMP) has also given a positive opinion for the use of HYMPAVZI for the same indication, indicating a broader acceptance and potential availability of the treatment in European markets.

Earlier in 2024, Pfizer achieved another regulatory milestone by receiving approval for its gene therapy treatment for haemophilia B, known as BEQVEZ (fidanacogene elaparvovec-dzkt), in the United States. This further demonstrates Pfizer’s leadership and innovation in developing advanced treatments for haemophilia, catering to a spectrum of medical needs within the patient community.

Overall, the approval of HYMPAVZI represents a significant advancement in the treatment landscape for haemophilia, offering a novel and effective option for patients. Pfizer’s continued efforts in this field reflect its long-standing commitment to improving the lives of individuals affected by these rare genetic blood disorders.