Trick, or treat? FDA plans Halloween adcomm for Ipsen’s second chance at rare disease drug
An oft-maligned rare bone disease program at Ipsen is going to get a closer look from regulators on a day that’s proven to be mighty spooky.
The FDA has scheduled an advisory committee to examine Ipsen’s palovarotene on Oct. 31, according to a notice posted in the Federal Register, setting up a showdown for a drug that once failed a Phase III test. The hearing will come about two months ahead of palovarotene’s decision date, which is slated for Dec. 29.
An Ipsen spokesperson confirmed the adcomm date, telling Endpoints News that it is “common” for the FDA to convene a panel of outside experts in areas with no treatment options, particularly in rare diseases.
Researchers had been developing the candidate to try to prevent new bone growth associated with fibrodysplasia ossificans progressiva (FOP) and multiple osteochondromas. Ipsen took on the drug following a $1 billion-plus acquisition of Canadian biotech Clementia Pharmaceuticals in February 2019, which had repurposed it after Roche punted on emphysema trials.
In December 2019, regulators slapped Ipsen with a partial hold on dosing patients 14 and under in a Phase II and Phase III study after reports of “early growth plate closure,” a condition that can severely stunt a child’s growth. The next month, the drug failed a Phase III futility test and Ipsen decided to pause dosing in all remaining pediatric patients from that study.
Ipsen appeared to turn things around in short order, resuming dosing a few months later after amending trial protocols. The company even won priority review in May 2021. But things took a turn after Ipsen withdrew its application in August 2021, citing the FDA’s request for additional data from its two pivotal studies.
The move came as a surprise to analysts but didn’t seem to dent their expectations. Jefferies’ Peter Welford said at the time that the withdrawal wouldn’t change his projection of $180 million in peak sales, which had assumed a 2021 US approval.
But Ipsen resubmitted its application this June, once again winning priority review. The company applied for approval in FOP in adults and children, including girls older than eight and boys older than 10. The drug has also been approved in Canada, winning an OK this past January.
Editor’s note: This article has been updated with comment from an Ipsen spokesperson.