FDA Tells Ipsen It Won’t Approve Palovarotene for FOP

The U.S. Food and Drug Administration notified Ipsen that it would not approve its experimental drug palovarotene for the rare bone disorder fibrodysplasia ossificans progressive without additional clinical trial data.

Photo: Howard Mayer, executive vice president and head of research and development for Ipsen

The agency is not seeking an additional study, only additional efficacy data from existing studies. Ipsen said it expected to respond in the first quarter of 2023 with the agency reviewing the drug in a six-month review cycle. The FDA has not announced a rescheduled date for the Endocrinologic and Metabolic Drugs Advisory Committee meeting for palovarotene.

Fibrodysplasia ossificans progressive (FOP) is an ultra-rare disease that causes permanent and continuous bone formation in soft and connective tissues like muscles, tendons and ligaments, also known as heterotopic ossification or HO. As bone continuously accumulates over time in joints and other areas of the body with flare-up episodes causing rapid bone formation, FOP severely restricts mobility and function. FOP impacts the lives of fewer than an estimated 400 people in the United States and 900 people globally.

Due to abnormal bone formation, in childhood and early adulthood people living with FOP may lose the permanent ability to move their neck, back, shoulders, chest, legs and arm joints. Without disease-modifying treatment, palliative care is the only treatment option and the median life expectancy is 56 years with untimely death caused by bone formation around the ribcage leading to breathing problems and cardiorespiratory failure.

Palovarotene is authorized for use in appropriate patients in Canada and United Arab Emirates where it is marketed as Sohonos (palovarotene capsules). Investigational palovarotene is under review with a number of regulatory authorities.

“Although this extends the review timeline for palovarotene, we continue to work with the FDA to provide the requested information and believe that investigational palovarotene has the potential to be an innovative treatment to reduce new abnormal bone formation to slow the progression of FOP,” said Howard Mayer, executive vice president and head of research and development for Ipsen. “Currently, people living with FOP in the U.S. have no approved treatment option to slow the progression of the disease and this remains our reason for being steadfast in our pursuit of bringing this potential treatment option for FOP.”

Author: Rare Daily Staff