The road to the U.S. market has been a winding one for Sohonos and Ipsen. Roche originally developed the medicine as a treatment for chronic obstructive pulmonary disease, but it failed in testing. The Canadian biotech Clementia Pharmaceuticals then licensed the medicine and in 2014 won orphan drug and fast track designations from the FDA to help speed development for FOP.
The initial studies went well enough to attract the attention of Ipsen, which agreed in 2019 to buy Clementia for as much as $1.3 billion. But clinical trials delivered mixed results for Ipsen, and the FDA rejected the drug in late 2022. Ipsen tried again in March with new analyses of previous research, a gambit that doesn’t always fly with regulators.