FDA Issues Clarification on Compounded GS-441524 for Feline Infectious Peritonitis (FIP)
On May 10, the Food and Drug Administration (FDA) issued an important update regarding products compounded from GS-441524, a nucleoside analog and the active metabolite of remdesivir, used in treating feline infectious peritonitis (FIP).
The FDA is aware of social media posts suggesting that compounded GS-441524 will become “legally” available starting June 1 in the U.S. However, the FDA emphasizes that animal drugs compounded from bulk drug substances remain unapproved and are not legally permitted.
FDA to Exercise Regulatory Discretion
Despite this, the FDA announced it will exercise regulatory discretion for compounding GS-441524 if compounders adhere to the Guidance for Industry (GFI) #256, titled “Compounding Animal Drugs from Bulk Drug Substances.”
GFI #256 Guidelines
GFI #256 outlines specific conditions under which the FDA will not enforce actions against compounded animal drugs. Key conditions include:
- Patient-Specific Prescriptions: Products must be compounded based on patient-specific prescriptions, not for general office stock, unless explicitly authorized by the FDA.
- Nominations for Non-Specific Prescriptions: Veterinarians seeking to obtain compounded animal drugs without a patient-specific prescription must nominate the bulk drug substance with a detailed justification for its use.
Challenges with Access to Remdesivir
Although remdesivir is FDA-approved and available for veterinary use under extralabel drug regulations (as per the Animal Medicinal Drug Use Clarification Act – AMDUCA), veterinarians have faced difficulties in accessing this medication. This has increased interest in compounding both remdesivir and GS-441524.
Collaborative Efforts for Office Stock Authorization
Recognizing the urgent needs of some feline patients, the American Veterinary Medical Association (AVMA) and the American Association of Feline Practitioners are working together to submit nominations to the FDA. These nominations aim to permit the use of office stock for both remdesivir and GS-441524, ensuring timely access to these critical medications.
By adhering to the FDA’s guidelines, veterinarians can ensure they are providing safe and effective treatments for FIP while remaining compliant with federal regulations.