CSL’s Hemgenix (etranacogene dezaparvovec) has been authorised as the first gene therapy for adults with severe and moderately severe haemophilia B (congenital Factor IX (FIX) deficiency) in Great Britain.
It has been granted a marketing authorisation for patients without a history of FIX inhibitors by the UK Medicines and Healthcare products Regulatory Agency (MHRA).
The MHRA decision follows conditional marketing authorisation from the European Commission (including Northern Ireland and the Republic of Ireland) and approval from the Food and Drug Administration (FDA) in the US.
It is based on results from the ongoing Phase III, open label, single-dose, single- arm, multicentre HOPE-B trial of 54 participants, the largest gene therapy trial in haemophilia B to date.
Stephen Allan, Country Manager, CSL Behring UK and Ireland, said: “This decision represents an important milestone for a potential new therapy option for people living with haemophilia B in the UK. We are now committed to working collaboratively with the National Institute for Health and Care Excellence to provide access to this innovative treatment for eligible patients across the UK.”
Clinical trial data
Data from the trial show that haemophilia B patients treated with a single infusion of etranacogene dezaparvovec demonstrated significant increases in mean FIX activity levels of 36.9% at 18-months, that were sustained at 36.7% at 24-months post-treatment, compared to the six-month lead in period.
This led to an adjusted annualised bleed rate (ABR) reduction of 64% during months 7-18 (primary end-point) and 7-24 of the study compared to the same lead-in period pre-infusion. Following infusion of etranacogene dezaparvovec, 96% of patients (52/54) discontinued routine FIX prophylaxis.
“The positive decision from the MHRA is the essence of great science delivering a medicine that we believe could potentially change the treatment paradigm for both people living with haemophilia B and the healthcare professionals who treat them,” said Dr Bill Mezzanotte, Head of Research and Development and Chief Medical Officer, CSL.
The clinical development of etranacogene dezaparvovec was led by uniQure and sponsorship of the clinical trials transitioned to CSL after it licensed global rights to commercialise the treatment.