German-based biotechnology company CSL Behring has received conditional marketing authorization (CMA) from the European Commission (EC) for its Hemgenix (etranacogene dezaparvovec) indicated for the treatment of hemophilia B in adults.

Hemgenix (also known as CSL222, previously known as AMT-061) is an adeno-associated virus five (AAV5)-based gene therapy intended to be given as a one-time treatment for moderately severe to severe hemophilia B (congenital Factor IX deficiency) in patients having no history of Factor IX inhibitors.

The conditional marketing clearance of Hemgenix by the European Commission was backed by the findings from the pivotal HOPE-B trial wherein hemophilia B patients treated with the gene therapy candidate experienced stable and durable increases in mean Factor IX activity levels, with a mean Factor IX activity of 36.9%, leading to an adjusted annualized bleed rate reduction of 64%.

The 54-patient study also demonstrated 96% of patients discontinued routine Factor IX prophylaxis following infusion of Hemgenix and 97% mean Factor IX consumption reduction at 18 months post-treatment, compared to the lead-in period.

Dr Bill Mezzanotte — CSL Chief Medical Officer and Research & Development Head said: “The approval of Hemgenix in Europe is the essence of great science delivering a medicine that we believe can transform the treatment paradigm for both people living with hemophilia B and the healthcare professionals who treat them.”

The European Commission has the authority to approve medicines for EU Member States, as well as in the EEA countries of Iceland, Norway, and Liechtenstein.

The UK regulatory body — the Medicines and Healthcare products Regulatory Agency (MHRA) is currently reviewing CSL’s submission for Hemgenix.

In November 2022, the US Food and Drug Administration approved Hemgenix for the treatment of hemophilia B in adults.

uniQure developed Hemgenix and transferred the sponsorship of the clinical trials to CSL after it licensed global rights to commercialize the treatment.

  CSL, CSL Behring, Dr Bill Mezzanotte, etranacogene dezaparvovec, European Commission, gene therapy, Hemgenix, hemophilia B, uniQure