Marstacimab-hncq

Pfizer has disclosed the death of a participant enrolled in a long-term extension study of its haemophilia therapy Hympavzi (marstacimab) following a thrombotic stroke after minor surgery.The patient, who had haemophilia A with active inhibitors, had been receiving weekly prophylactic doses of Hympavzi for three years when the fatal event occurred this month, according to a joint statement from the World Federation of Hemophilia and the National Bleeding Disorders Foundation.In a letter dated Dec. 22 to haemophilia community partners, Pfizer noted that it is working with trial investigators and an independent data monitoring committee to assess the "complex, multifactorial circumstances" surrounding the case, including comorbidities and concomitant medications, and said regulators have been informed. Causality has not yet been established.Hympavzi was approved in the US and EU in late 2024 for routine prophylaxis in adults and adolescents aged 12 and older with severe haemophilia A or B without inhibitors and has since been rolled out in multiple global markets. Pfizer has been pursuing label expansion into inhibitor populations following positive data from the Phase III BASIS study showing it reduced bleeds by a significant 93% over on-demand therapy. A more detailed readout was presented at the American Society of Hematology (ASH) conference this month.Thrombosis has been identified as an adverse event of special interest for Hympavzi and other rebalancing agents, which work by targeting tissue factor pathway inhibitor (TFPI) to increase thrombin generation for clot formation. Similar safety concerns have emerged across other non-factor haemophilia drugs, and use of Hympavzi should include close monitoring for thrombosis symptoms and other adverse events, especially in surgical settings in combination with clotting factor concentrates or bypassing agents.Though it was the first the anti-TFPI to enter the US and European markets for haemophilia A or B, Hympavzi now faces competition from Novo Nordisk's once-daily prophylactic haemophilia treatment Alhemo (concizumab-mtci), a TFPI antagonist authorised a year ago for haemophilia patients with inhibitors.

iStock, Alexandros Michailidis The patient, who died on December 14, was originally enrolled in a Phase III study in 2022 and transitioned into an extension phase in 2023. A patient taking Pfizer’s approved hemophilia A therapy Hympavzi has died, the New York pharma disclosed Monday . The patient had been participating in a long-term follow up clinical trial featuring Hympavzi, which was approved in October 2024 for patients with hemophilia A or B without inhibitors. Pfizer revealed the death in a letter to patient communities. The death occurred on December 14 . The patient was originally enrolled in a Phase III study that occurred in 2022 and transitioned into an extension phase in 2023. They continued to receive Hympavzi as a prophylaxis plus recombinant factor VIIa to prevent bleeding after a minor surgery. The patient experienced serious adverse events including a stroke and bleeding in the brain. Pfizer said it is working with the data monitoring committee to gather information about the death. The company noted co-existing medical conditions and other medications the patient was taking at the time. Hympavzi was approved in the U.S. in October 2024 as a once-weekly subcutaneous prophylactic injection for hemophilia A or B. It has since been granted authorization in Europe. The therapy is an IgG1 monoclonal antibody that targets the Kunitz domain 2 of the tissue factor pathway inhibitor protein, which prevents blood clotting. This mechanism of action allows Hympavzi to enhance coagulation in hemophilia patients. Earlier this year, Pfizer discontinued the hemophilia gene therapy Beqvez in all global markets, citing low patient interest and a shift to Hympavzi. Pfizer partnered with Sangamo Therapeutics on Beqvez. In September 2024, Pfizer pulled the sickle cell disease therapy Oxbryta from the market after new data showed a higher risk of death and complications in patients who received it.