Ipsen still out of regulatory luck as European Commission rejects rare disease drug

While Ipsen’s troubled rare disease candidate was given a second chance by the FDA, the regulator’s European equivalents haven’t been as sympathetic.

The European Commission has ruled not to grant marketing authorization for palovarotene to treat an ultra-rare bone growth disorder called fibrodysplasia ossificans progressiva (FOP), Ipsen revealed this morning. The decision won’t have come as complete surprise, following a negative opinion by the Committee for Medicinal Products for Human Use back in May.

Despite the regulatory setback, Ipsen said it will continue to seek regulatory approvals in other countries and regions. It may still succeed in the U.S., where the FDA initially rejected the biotech’s application. That decision came two months after the agency delayed an advisory panel meeting to discuss palovarotene and requested additional data.

But when Ipsen sent over the information, the FDA scheduled a decision date of Aug. 16 for the resubmitted approval application. The extra data included additional analyses spanning a range of trials, including MOVE, the first phase 3 study on people with FOP.

Ipsen tried a similar approach in Europe, where it requested that the European Medicines Agency (EMA) reexamine the recommendation of its committee in January not to authorize palovarotene. At the time, the biotech said it would call for the decision to be reviewed.

While that attempt clearly didn’t prove as effective, it at least seems that the European Commission’s decision was priced in by investors. Ipsen’s stock remaining unmoved around the 111 euro mark in Thursday morning trading on the Paris stock exchange.

“We believe that our clinical data provide evidence supporting the effect of palovarotene on the reduction of new, abnormal bone formation, known as heterotopic ossification, which characterizes the disease,” Ipsen’s head of R&D Howard Mayer, M.D., said in the release. “We are therefore disappointed that the European Commission decided not to approve this treatment for patients with FOP in Europe.”

The FDA and EMA rejections were only the latest obstacles in what has been a difficult journey for palovarotene since Ipsen acquired the asset in a $1.31 billion purchase of Clementia Pharmaceuticals in 2019. The drug would go on to receive a four-month partial clinical hold on a study in pediatric populations with FOP and multiple osteochondromas after evidence of cases of early growth plate closure. Dosing in a phase 3 FOP trial that included adults was also paused after early evidence suggested the trial would not meet its primary endpoint.

Ipsen’s persistence can be explained by the fact that there remain no FDA-approved drugs for FOP. BioCryst axed development of a FOP candidate in November, leaving Ipsen and Regeneron as the two major players left in the space. Should the FDA’s decision go Ipsen’s way in August, it will still be ahead of Regeneron, which is expected to submit its approval application next year.