FDA Announces Position on Use of Compounded GS-441524 to Treat FIP

Because no FDA approved drug is available to treat Feline Infectious Peritonitis in cats, the U.S. Food and Drug Administration does not intend to enforce new animal drug approval requirements for products compounded from GS-441524, when prescribed by a veterinarian for a specific cat patient for the treatment of Feline Infectious Peritonitis under the conditions listed in Guidance for Industry (GFI) #256 Compounding Animal Drugs from Bulk Drug Substances.

The FDA is aware of social media posts suggesting that compounded GS-441524 will be “legally” available in the United States starting June 1. The agency reminds compounding pharmacies, veterinarians and pet owners that animal drugs compounded from bulk drug substances are unapproved drugs and are not, in fact, legal. However, in GFI #256, the FDA has described certain conditions where the agency does not intend to take enforcement actions for compounded products for use in animals.