uniQure Presents Data from HOPE-B Pivotal Gene Therapy Trial in Patients with Hemophilia B at ASH Annual Meeting

The following is an excerpt from a press release from uniQure. Read the full press release here.

uniQure, a gene therapy company advancing transformative therapies for patients with severe medical needs, today announced the late-breaking presentation of initial data from its pivotal, Phase III HOPE-B gene therapy trial of etranacogene dezaparvovec, an investigational adeno-associated virus five (AAV5)-based gene therapy for the treatment of patients with severe and moderately severe hemophilia B. This is the first data set to be reported from a Phase III gene therapy study in hemophilia B and, with 54 patients, the largest set of patients receiving a single gene therapy investigational product to be reported to date. These clinical data will be presented today in an oral session at the virtual 62nd Annual Meeting of the American Society of Hematology. The oral presentation slides are available in the Investors section of uniQure’s website under Investor Downloads.

“These initial data on etranacogene dezaparvovec are encouraging, because thus far in these patients, severe hemophilia B appears to have been transformed into a functionally curative state following administration of this one-time gene therapy, providing cessation in bleeding for a majority of patients and no need for ongoing, chronic replacement therapy,” stated Steven Pipe, M.D., professor of pediatrics and pathology and pediatric medical director of the hemophilia and coagulation disorders program at the University of Michigan, and the principal investigator of the HOPE-B pivotal trial.

“Importantly, these data also show that those patients in the trial who may not have been eligible for other gene therapies because they had pre-existing neutralizing antibodies (NAbs) have achieved results with etranacogene dezaparvovec that are comparable to the results of patients who did not have pre-existing NAbs,” he added. “This is an important distinction as this is the only known clinical trial that has maximized patient eligibility in this way. The initial data also show that etranacogene dezaparvovec has been generally well tolerated to date.”

Patients in the Phase III HOPE-B clinical study were initially enrolled into a prospective, observational lead-in period of at least six months during which bleeding events and FIX replacement therapy usage were monitored. All patients required prophylactic routine FIX replacement prior to entering the clinical trial, and patients were not excluded from the trial based on pre-existing NAbs to AAV5. The primary endpoints in the study include FIX activity at 26-weeks and 52-weeks after dosing and annualized bleeding during the 52 weeks after dosing.

More than 80 percent of the 54 patients treated in the open-label study had severe hemophilia with endogenous FIX activity at ≤1%. Forty-three percent of patients in the study had NAbs to AAV5 up to a maximum titer of over 3,200. Fifty-four patients reported 123 bleeds during the lead-in phase of the study, even while they remained on prophylactic replacement therapy.

Read the full press release here.