New data on gene therapy in haemophilia released at ASH 2023

Did you attend the 65th American Society of Hemophilia in San Diego in December? In case you missed it, we wanted to highlight new data presented from etranacogene dezaparvovec clinical trials, reporting transgene efficacy and safety in patients with HIV and HCV/HBV infection, and the latest long-term efficacy data at 3 years post-infusion.

The latest results from the HOPE-B trial were presented, reporting efficacy of a single dose of etranacogene dezaparvovec 3 years after administration in adult patients with severe or moderately severe haemophilia B. Long-term follow-up data show that a single dose of etranacogene dezaparvovec resulted in long-term endogenous FIX Padua expression and superior bleeding protection compared to FIX prophylaxis, with a favourable safety profile over 3 years post-administration. Access the abstract "Long-Term Bleeding Protection, Sustained FIX Activity, Reduction of FIX Consumption and Safety of Hemophilia B Gene Therapy: Results from the HOPE-B Trial 3 Years after Administration of a Single Dose of Etranacogene Dezaparvovec in Adult Patients with Severe or Moderately Severe Hemophilia B" from Steven Pipe et al. here.

In addition, new data analyses report the efficacy of etranacogene dezaparvovec in sub-populations of haemophilia B in patients with HIV or a history of chronic HCV/HBV infections, where no differences in AAV-based FIX gene expression were observed in these patients compared to non-infected trial participants. Etranacogene dezaparvovec was observed to be safe and effective in a subset of Phase 2b and Phase 3 study participants living with HIV. Read the full abstract "HIV Comorbid Infection and Liver-Directed AAV-Based Gene Therapy in Adults with Severe and Moderately Severe Hemophilia B: Efficacy and Safety Results from Phase 2b and the Pivotal Phase 3 HOPE-B Trials 3 Years after Administration of a Single Dose of Etranacogene Dezaparvovec" from Steven Pipe et al. here.

The majority of HOPE-B trial participants were adults with a history of chronic HCV and/or HBV infection without active viral disease or evident pre-existing liver fibrosis; safety and efficacy were observed in these participants. Read the full abstract "Adult Patients with Hemophilia B and with a History of Chronic HCV/HBV Infection Receiving Liver-Directed Gene Therapy Demonstrated Long-Term Bleeding Protection and Sustained FIX Activity: Efficacy and Safety Results from the HOPE-B Trial 3 Years after Administration of a Single Dose of Etranacogene Dezaparvovec" from Annette von Drygalski et al. here.