Amicus' Pompe approval hopes stall after COVID scuttles WuXi FDA inspection

Amicus Therapeutics must wait a while longer for an approval decision on its rare disease candidate AT-GAA after stumbling over its second delay of the year. Still, the company remains undeterred about its prospects in Pompe disease.

The U.S. FDA has had to sideline Amicus’ biologics license application for the biologic component of AT-GAA, cipaglucosidase alfa, because COVID-19 travel restrictions thwarted a planned inspection of a Chinese manufacturing site operated by CDMO WuXi Biologics.

Cipaglucosidase alfa was up for an FDA verdict on Oct. 29. It’s currently unclear how long the latest delay on Amicus’ application will last. The FDA hasn’t provided a new target action date as the agency continues to monitor the situation in China, the company said Friday.

As Amicus waits on the FDA to complete the necessary inspection, the company is holding firm in the belief that the FDA will approve the two components of AT-GAA together—the other being miglustat, which is used to stabilize the drug’s biologic half.

It’s a question of “‘when’ not ‘if’” the two-part med scores its green light, Amicus CEO Bradley Campbell said in a release Friday.


In light of the delay, Amicus says it’s now “actively engaged” with the regulator to develop plans and hammer out logistics for a preapproval inspection scheme. Amicus stressed that the pandemic travel snafu was the “sole reason” for the FDA’s action date extension.

“We are now one step away from the necessary approvals for AT-GAA in the U.S.,” CEO Campbell added in his statement.

AT-GAA has received breakthrough-therapy designation in the U.S. Across the pond, the med’s regulatory review is still on track, and the European Medicines Agency’s Committee for Medicinal Products for Human Use is expected to hand down its ruling on the drug’s fate before the year is out. Europe does not require a preapproval inspection, so the WuXi-related travel restrictions shouldn’t impact that decision.

This is the second FDA delay for Amicus’ drug this year. Back in May, the company said the FDA had drawn out its review timeline to parse through additional information as part of an ongoing review process. The extension wasn’t related to requests for any additional data, Amicus pointed out at the time.

Earlier this year, Amicus speculated the extension would give the FDA ample time to wrap up its WuXi inspection, but, unfortunately for the company, things did not go to plan.

Throughout the COVID-19 era, and especially in the pandemic’s first year, coronavirus-fueled travel restrictions upended review schedules for scores of drugs. In November 2020, for instance, the FDA delayed action on Revance’s frown-line injection daxibotulinumtoxinA because it couldn't make it out to the company's Newark, California, manufacturing facility on time, which the regulator blamed on COVID-19 restrictions. The FDA ultimately spurned Revance’s application this October.

That same month, the FDA was unable to conduct an inspection of a Lonza facility in Texas slated to produce the viral vector for Bristol Myers Squibb's liso-cel, now known as Breyanzi. The drug is now approved, but investors had hoped for an approval before year-end as part of lucrative contingent value rights issued with the Celgene buyout.