Just two weeks after showing off positive results at the American Society of Hematology (ASH) meeting, uniQure and partner CSL have been hit with an FDA clinical hold for their bleeding disease treatment etranacogene dezaparvovec.
The gene therapy has been in trials for hemophilia B in the hope it could provide a one-and-done approach to effectively curing the condition.
Results posted at the ASH conference in early December mostly backed this approach up, showing the therapy curbed bleeding episodes and nearly eliminated the need for infusions of clotting factor IX in a phase 3 study testing it in severe or moderately severe hemophilia B.
But now, uniQure says one patient dosed more than year ago has been found to have a form of liver cancer. It is not clear whether this is drug-related, however; uniQure points out that the patient “has multiple risk factors” for liver cancer, including a twenty-five-year history of hepatitis C, hepatitis B virus, evidence of nonalcoholic fatty liver disease and advanced age.
All of which could mean the lesion found during a routine scan could be as a result of these factors, and not the therapy. But the FDA has still slapped a hold while this is investigated, dragging uniQure’s shares down nearly 20% premarket on the news Monday morning.
Its entire hemophilia B gene therapy program, including the pivotal phase 3 HOPE-B study, has been hit by the hold, but the company does not expect this to hit its timelines for getting the drug to market.
The biotech said, however, that patient dosing “is complete in each of uniQure’s three hemophilia B gene therapy studies, and there is no plan to enroll or treat additional patients.”
“Patient safety will always be our top priority, and we are working closely with the FDA and our advisors to conduct a thorough investigation into the cause of this event which we expect to be completed in early 2021,” said Ricardo Dolmetsch, Ph.D., president of R&D at uniQure.
“We will investigate whether there is a relationship to treatment. At this time, we do not have adequate data to determine a possible causal relationship, especially in the context of the other known risk factors.”
“All patients in our hemophilia B gene therapy program, including the 54 patients in HOPE-B, will continue to be monitored by their care teams while we gather additional information as rapidly as possible,” added Matt Kapusta, CEO of uniQure.
“We do not anticipate any impact to our regulatory submission timeline for the hemophilia B program as a result of this clinical hold.”