FDA Expands Marstacimab Indication in Hemophilia A and B - Takeaways - MDSpire

FDA Expands Marstacimab Indication in Hemophilia A and B

Phase 3 BASIS and BASIS KIDS data supported the expanded indication across pediatric and inhibitor-pretreated populations.

  • By

  • Kathryn Wighton

  • June 8, 2026

  • 3 min

Share

  • 1

    The FDA approved marstacimab-hncq (HYMPAVZI) for routine prophylaxis in hemophilia A and B patients aged 6 years and older.

  • 2

    HYMPAVZI is the first subcutaneous non-factor therapy for pediatric patients aged 6 to 11 years with hemophilia B.

  • 3

    In the phase 3 BASIS trial, marstacimab reduced the mean annualized bleeding rate by 93% compared to on-demand intravenous treatment.

  • 4

    Marstacimab targets the Kunitz 2 domain of tissue factor pathway inhibitor to restore balance between bleeding and coagulation.

  • 5

    Common adverse reactions include injection-site reactions, headache, and pyrexia, with warnings for thromboembolic events and hypersensitivity.

Original Source(s)

FDA Expands Marstacimab Indication in Hemophilia A and B

  • by Kathryn Wighton

  • June 8, 2026

Related Content

FDA Expands ASCENIV Pediatric Use

Label change follows completion of required pediatric evaluation and updates prior age restrictions for treatment eligibility.

Phthalates Linked to Shorter Gestation

Researchers linked several pregnancy urinary biomarkers—especially plasticizer and combustion-related chemical metabolites—to small shifts in gestational age and fetal growth measures in the ECHO Cohort.

Combined Clavicle Model May Improve Age Estimates

Combined approach shows higher sensitivity than traditional thresholds for classifying legal adulthood.