Forty people with fibrodysplasia ossificans progressiva (FOP), aged 7 to 53 years, participated in the phase II trial of palovarotene, a selective gamma retinoic acid receptor agonist, versus placebo: 10 received placebo, 9 were treated with 5mg/d palovarotene for 15 days and then 2.5mg/d for a month, and 21 took 10mg/d palovarotene for 15 days and then 5mg/d for a month.
- At 6 weeks, radiographs showed that all participants on palovarotene 10/5mg, 88.9% of participants on palovarotene 5/2.5mg and placebo responded to treatment: no or little heterotopic ossification at the site of flare-ups.
- At 12 weeks, the proportions increased to 95% for participants on palovarotene 10/5mg, 88.9% of participants on palovarotene 5/2.5mg and 77.8% of participants on placebo.
- The mean volume of new heterotopic ossifications measured by CT scan at 12 weeks was : 3.8×103 mm3 on palovarotene 10/5mg, 1.3×103 mm3 on palovarotene 5/2.5mg and 18×103 mm3 on placebo.
This encouraging, but not statistically significant, trend in the effects of palovarotene is being confirmed by an international multicenter phase III study, the MOVE trial, which is still ongoing, including in France (Hôpital Necker, Paris).
- It should be noted that palovarotene (Sohonos®) was approved for the first time in Canada in January 2022 based on preliminary data from the MOVE trial.
- Applications for marketing authorization (MA) in the United States (June 2022) and in Europe (2021) for pavolarotene for the treatment of FOP are currently under review by the regulatory agencies.
Health Canada Approves Ipsen’s Sohonos™ (palovarotene capsules) as the First Approved Treatment for Fibrodysplasia Ossificans Progressiva. Ibsen, January 24th, 2022 press release
Ipsen announces U.S. FDA Priority Review for palovarotene New Drug Application in patients with fibrodysplasia ossificans progressiva following resubmission Ibsen, June 29th, 2022 press release
