The FDA has rejected plans from Amicus Therapeutics to seek speedy approval of an experimental drug for Pompe disease, calling instead for more data the Cranbury, NJ, company hopes to accrue over the next year.
The FDA told Amicus (NASDAQ: FOLD) that its “current clinical package is not sufficient” to support what’s known as accelerated approval, when the agency clears a drug off of a thinner than usual body of evidence. Amicus plans to submit more information to the FDA over the next year to support “further discussions” of accelerated approval of the drug, known as AT-GAA, the company said in a statement.
The move is the second such setback this year for Amicus, which is facing competitive pressure from Sanofi (NYSE: SNY) and others with experimental Pompe drugs and gene therapies—possible one-time, long lasting treatments—in development. Amicus has reported positive results for AT-GAA in a small, early-stage study and has been using that data to aggressively pursue streamlined approval paths in both the U.S. and Europe. But as with the FDA, European regulators in June nixed plans for a quick approval, asking for more data. Some analysts surmised Amicus may have more luck in the U.S., where “recent orphan drug approvals have fared better” than in Europe, wrote Leerink Partners analyst Joseph Schwartz in June.
To try again for accelerated approval in the U.S., Amicus plans to add a new arm to its current early stage study, amass more long-term results, and wrap up a “natural history” study in Pompe that helps describe the natural trajectory of a disease, it said in the statement.
Amicus has also outlined a late-stage trial for AT-GAA, which would compare its drug to standard-of-care enzyme replacement therapy in about 100 Pompe patients. The goal would be a statistically significant benefit on a six-minute walk test after 12 months of treatment. Amicus expects to start the study later this year.
Pompe is a genetic disease that affects between 5,000 and 10,000 people worldwide, according to the United Pompe Foundation. The disease causes muscles to progressively weaken, causing heart and lung damage and affecting patients’ ability to move. The disease is caused by the lack of an enzyme that breaks down glycogen. Pompe patients can currently get frequent infusions of the enzyme replacement therapy alglucosidase alfa (Lumizyme), from Sanofi. The Amicus drug is pill.
Amicus has had its share of ups and downs with regulators in the past. Just last month, the FDA approved an Amicus drug for Fabry disease, migalastat (Galafold), on an accelerated basis, but only after a decade-long saga with various twists and turns. Here’s more on that story, and AT-GAA.
Amicus shares ticked down roughly 1 percent in pre-market trading Monday.