The professor of pediatric hematology/oncology at CS Mott Children’s Hospital discussed 3-year follow-up data from the HOPE B trial of the approved gene therapy, branded as Hemgenix.
“People continue to be interested in the durability of the response, what the patient experience is, as far as bleeding events, the need for Factor IX, additional dosing, and just the overall safety profile... Now through 3 years, 51 of the 54 participants remain off continuous factor IX prophylaxis, so pretty remarkable. The 3 that did, I think we have some explanation for.”
New, 3-year follow-up data of the phase 3, open-label, single-arm HOPE B trial (NCT03569891) have continued to support the use of the approved, single-dose etranacogene dezaparvovec (Hemgenix; CSL Behring/uniQure) gene therapy in men with severe or moderately severe hemophilia B, with or without preexisting AAV5 neutralizing antibodies (NAbs), over standard of care factor IX prophylaxis.
The data were presented at the 2023 American Society of Hematology (ASH) Annual Meeting & Exposition, held December 9-12, in San Diego, California, by Steven W. Pipe, MD, a professor of pediatric hematology/oncology at CS Mott Children’s Hospital.
CGTLive spoke with Pipe to learn more about the 3-year follow-up data. He shared the positive data and went over the 3 cases of patients that had to use Factor IX prophylaxis. These cases were, 1, a patient who only received 10% of the dose and never discontinued prophylaxis; 2, a patient with a very high AAV5 NAbs titer of 1:3212; and 3, a patient whose Factor IX levels declined after a case of transaminitis which was presumed to be an immune reaction to the vector and resumed prophylaxis 30 months after treatment.