Pfizer’s Hympavzi Gets FDA Approval for Expanded Indication

Editor’s Take: The FDA determined significant medical need exists for Hympavzi to treat hemophilia with inhibitors to factors VIII/IX.

Pfizer gained U.S. FDA approval for expanded indications of Hympavzi (marstacimab-hncq) for treatment of patients with hemophilia A or B. This includes patients 12 years or older with inhibitors, and pediatric patients (ages 6 to 11) with or without inhibitors.

In the United States, Hympavzi’s indication now covers routine prophylaxis to prevent or reduce frequency of bleeding episodes. Specifically, this means patients with hemophilia A with or without factor VIII inhibitors, or hemophilia B with/without factor IX inhibitors.

Hympavzi Getting Regulatory Attention

The European Commission approved a similar, though not identical, expanded indication in May. The FDA had previously announced the indications it just approved were being considered under Priority Review as of early February.

Such inhibitors to factor replacement therapy limit treatment options, and are linked to increased risk of uncontrolled bleeding. Inhibitory antibodies develop in approximately 20% of patients with hemophilia A, and 3% of those with hemophilia B. Factor replacement no longer prevents or stops bleeding episodes for these patients—especially those refractory to immune tolerance induction therapy.

Hympavzi’s combination of prophylactic bleed protection and once-weekly subcutaneous administration eliminates a need for routine treatment-related lab monitoring.

Pfizer History in Hemophilia

Pfizer Chief U.S. Commercial Officer and Executive Vice President Aamir Malik said the subcutaneous option especially impacts the pediatric population.

“We believe Hympavzi can become a transformative option and meet a significant medical need,” Malik said. “[It’s] the latest step in Pfizer’s more-than-40-year commitment to advancing care and quality of life for people living with hemophilia.”

The FDA’s decision was based on results from a Phase III trial (BASIS). Overall, this reduced mean treated annualized bleeding rate by 93% compared with on-demand intravenous treatment with bypassing agents.