Compounded, veterinarian-prescribed treatment for FIP now available in United States and Canada 

Bye bye, black market! Veterinarians can now take an active role in the treatment of their patients with FIP through a compounded drug now for sale in the US and Canada.

By Emily Singler

Stokes Pharmacy, a compounding pharmacy, started selling a compounded prescription treatment for feline infectious peritonitis (FIP) on June 1, 2024.  This allows veterinarians to prescribe medication for their patients and hopefully carry small amounts of the compounded drug on their shelves to allow their sick patients to start treatment immediately.  

The current FIP treatment landscape 

While countries such as the United Kingdom and Australia have versions of GS-441524 available for the treatment of FIP in cats, there is still no approved drug in the United States or Canada.  This has left veterinarians, cat owners, and sick cats in a precarious state where the only options have been to refer owners to Facebook groups where non-veterinarians orchestrate the black-market sale of unlabeled, untested vials of medication costing thousands of dollars with no guarantees of safety or efficacy and little recourse in the case of a poor outcome.  In some cases, this option has proved to be lifesaving, but it certainly is far from ideal.  

Most recently, there have been reports of veterinarians successfully prescribing remdesivir, a similar drug that is now fully FDA-approved for use in humans, for extra-label use in cats.  Even though this drug seems to work very well against FIP, it is still not readily available and therefore not a reliable solution for cats who need treatment now.   

Hope for an FDA-approved drug in the United States still exists, as researchers at the University of California Davis continue to study the disease and possible treatment options, and Anivive Lifesciences reports on their website that they are “fully committed to working with the FDA to earn approval of a solution that is safe, effective, and affordable.” No timeline has been offered yet as to when an approved drug may be available for cat owners.  

Compounded GS-441524 in the US and Canada 

Mike Tursi, President and CEO of Stokes Pharmacy, recounts that he was contacted by BOVA, a compounding pharmacy operating in Australia and the UK, to discuss compounding GS-441524 for sale in the United States by prescription.  After inspecting the Stokes Pharmacy facilities, BOVA agreed to license their formula and data to Stokes for compounding of GS-441524 in the United States.  BOVA UK is also shipping the drug to Canada for sale there.   

In contrast to the black-market product and remdesivir—both of which are injectable — the compounded product is a tunaflavored oral tablet.  Recommended doses vary based on the patient’s clinical signs, to be administered once every 24 hours or split into two doses every 12 hours for 84 days minimum. Tablets can be split, and Tursi describes that some cat owners have had success crushing the tablets to create a slurry in cases where tablets were not tolerated by the patient.  

The FDA’s response 

The FDA has reported that they are aware of the compounded product and that they do not plan to take “enforcement actions” against products compounded for the treatment of FIP in cats that are prescribed by a veterinarian for specific feline patients.  Tursi indicated that they have been in contact with the FDA and that the compounded product is under review with the FDA in accordance with the Guidance for Industry (GFI) #256, which relates to the ability of a veterinarian to purchase compounded drugs for office stock without a specific patient prescription.  This would allow veterinarians to administer initial doses of the drug to sick patients while their owners are waiting for their prescribed medication to ship from the compounding pharmacy.  

Getting veterinarians involved 

Tursi hopes that the availability of a product compounded in the United States using a known formula that has been successfully used and studied in the treatment of cats in the UK and Australia will add a previously missing layer of safety and control to the treatment of this deadly disease, at least until an FDA-approved drug is available.  Veterinarians will also occupy a more central role in patient treatment with this option, which is important to Tursi. “We don’t want to be the veterinarians,” he clarifies. “When pet owners call, we direct them to their veterinarian.” 

Since veterinarians have been mostly excluded from the treatment of FIP in the past, Stokes recognizes there may be some hesitancy on the part of veterinarians to take on the liability of prescribing this compounded product for their patients.  As such, they are offering a series of informational RACE-approved webinars for veterinary professionals presented by subject matter experts from Australia, the UK, and the US.  

Further reading:  

Retrospective study and outcome of 307 cats with feline infections peritonitis treated with legally sourced veterinary compounded preparations of remdesivir and GS-441524   

Outcomes of treatment of cats with feline infectious peritonitis using parenterally administered remdesivir, with our without transition to orally administered GS-441524 

Feline Infectious Peritonitis: European Advisory Board on Cat Diseases Guidelines 


Cover photo credit: via Getty Images Plus 

 Disclaimer: The views expressed, and topics discussed, in any NEWStat column or article are intended to inform, educate, or entertain, and do not represent an official position by the American Animal Hospital Association (AAHA) or its Board of Directors. 



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