FDA Delays Advisory Meeting on Ipsen’s FOP Drug

Rare Daily Staff

Ipsen said the U.S. Food and Drug Administration has postponed the planned Endocrinologic and Metabolic Drugs Advisory Committee meeting for palovarotene, its experimental therapy for the rare bone disorder fibrodysplasia ossificans progressive, until a later date to be confirmed.

The advisory committee meeting was scheduled for October 31, but the agency notified Ipsen it wanted new information on palovarotene clinical trial data. The company said the data the agency is seeking does not relate to the safety profile of palovarotene.

Ipsen said it is working to fulfil the request.

Fibrodysplasia ossificans progressive (FOP) is characterized by new bone formation outside of the normal skeletal system, like in soft connective tissues, a process known as heterotopic ossification, which can be preceded by painful soft tissue swelling or “flare-ups.” Flare-up episodes are common and are a substantial contributor to the formation of new bone, however bone can also form in the absence of a flare-up. Once formed, it is irreversible and leads to loss of mobility and shortened life expectancy. It is an ultra-rare genetic disorder.

Palovarotene is an oral, selective RARγ agonist developed as a treatment for people living with the debilitating ultra-rare genetic disorder, FOP. The treatment was acquired by Ipsen through the acquisition of Clementia Pharmaceuticals in April 2019. It is a member of the retinoid class of drugs that is associated with birth defects in humans. In January, the company won approval for pavalarotene in Canada, where it is marketed as Sohonos.

This is not the first setback for Ipsen in its efforts to bring palovarotene to market. It first sought FDA approval of Palovarotene in May 2021, but the company withdrew its application three months later. Following discussions with the agency at that time, it said it would resubmit its application following additional data analysis.

Ipsen began developing palovarotene following its $1.3 billion acquisition of Clementia Pharmaceuticals.