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MT21-005: Prospective evaluation of unlicensed GS-441524-like antiviral therapy for treatment of feline infectious peritonitis

Feline infectious peritonitis (FIP) is a common, viral disease affecting cats worldwide. Until very recently, FIP was considered uniformly fatal with no available treatment. It was discovered in 2018 that the antiviral compound GS-441524 is highly effective at treating FIP in both laboratory cats and privately-owned cats, but this compound remains patented and unavailable for legal veterinary use. As a result, multiple unlicensed drug manufacturers began selling this compound to cat owners over the internet. The aims of this proposal are two-fold: 1) to prospectively evaluate the at-home use of unlicensed GS-441524-like antiviral drugs to treat FIP through serial, well-timed surveys of internet users of these compounds; and 2) to quantify the concentration, purity, and acidity of popular brands of unlicensed GS-441524-like compounds sold on the internet. Our global hypothesis is that unlicensed GS-441524-like antiviral therapy for FIP is generally highly effective, but efficacy is currently limited by lack of veterinary oversight and lack of quality control of available products. This research will greatly enhance our understanding of the current practice of unlicensed treatment for FIP, which will not only provide much needed insight for how to help these patients when they are presented to a veterinary clinic, but will also hugely advantage clinicians if and when GS-441524 becomes available for legal use in cats. Furthermore, this phenomenon can serve as a ‘test case’ for crowd-sourced entities rising to fill an obvious void left by the veterinary and pharmaceutical industries, which will provide many valuable lessons to our profession.

EveryCat Health Foundation has combined funding from the Miller Trust and the Bria Fund to fund this grant.

Grant ID: MT21-005

Status: Active

Year Funded: 2021

Amount awarded: $4,500

Investigator: Samantha J.M. Evans, DVM, PhD, DACVP; The Ohio State University, College of Veterinary Medicine