Close this search box.

Feline Infectious Peritonitis: A History

By Steve Dale, CABC

The story of feline infectious peritonitis (FIP) has always been a complicated one dating to when legendary Dr. Niels Pedersen, now Professor Emeritus University of California, Davis School of Veterinary Medicine described the disease in his ground-breaking textbook Feline Husbandry: Disease Management in the Multiple Cat Environment. 

Now, it is a new treatment in the U.S. and the FIP story could be a Netflix series.

Greatly as a result of decades of funding from the non-profit Winn Feline Foundation (now EveryCat Health Foundation) and, more recent, support from Zen by Cat and others around the world, today we know how this complex disease forms in cats in the first place. Politics – in a weird sort of way – even plays into the FIP story. After her Birman kitty succumbed to FIP, Susan Gingrich (former Republican speaker Newt’s sister) began a fund named for Bria and raised thousands of dollars with Winn Feline. 

By the early 2000’s, FIP was finally fully understood. Cats in multi-cat environments may inevitably get the enteric feline corona virus, which is benign, causing little – if any- illness. However, in a still unknown (but not insignificant) percent of kitties, inside the cat the coronavirus mutates into an immune mediated disease call FIP, which occurs in various forms (effusive or wet; non-effusive or dry, neurologic, or ocular). 

Why does this mutation occur in some kitties and not others? That mostly remains a mystery, although both individual and breed genetics, and stress are all factors. 

When a kitten was properly diagnosed, it was a death sentence until everything changed in 2019.

Several years before that Dr. Pedersen thought an obsolete Ebola drug, an anti-viral sitting on the shelf at the pharma company Gilead, may in some way treat cats with FIP. It turned out not to work to treat them but, in fact, to cure nearly all of them.

Soon enough though, Gilead stopped allowing the use of their drug for cats. No problem, Pedersen collaborated with Dr. Yunjeong Kim, associate professor in the department of pathobiology and diagnostics Kansas State University College of Veterinary Medicine. They demonstrated a similar antiviral compound, known as GC376, had an even higher degree of success to treat FIP. 

Anivive Lifesciences a veterinary biotechnology company took notice and is now in the process of approving GC376 with the FDA Center for Veterinary Medicine. The FDA has been particularly sluggish to approve, but it’s expected to eventually happen. 

Back to 2019, the EveryCat Health Foundation, (then still called the Winn Feline Foundation), brought together most of the investigators from around the globe to ever have been funded for FIP studies for a symposium at the University of California, Davis. The group was led by, of course, Dr. Pedersen. At that event I had the honor of announcing the consensus, “FIP moving forward is now treatable and no longer considered fatal.” There wasn’t a dry eye in the house.

However, because there was no approved or even available drug in the U.S., Chinese companies had begun to offer an alternative, what Dr. Dave Bruyette, CEO of Anivive called “Goo.” It was unknown if the unauthorized products from China worked. 

It wasn’t long before peer-reviewed published studies confirmed what online sites such as FIP Warriors had known for some time. Yes, the Chinese products do work, and save countless lives. 

It took a while for veterinarians to first know about the availability of these products even from China, or to point pet parents in this direction while simultaneously offering supportive care for the sick kitties, such as fluids, additional drugs to deal with issues like nausea and sometimes fluid therapy. After all, veterinarians could theoretically lose their license supporting unapproved online products from China.

Meanwhile, the SARS Coronavirus pandemic hit the world, and there were no treatments. Desperate for an antiviral, the U.S. government looked at Remdesivir, based on the drug’s success with felines. If not for the EveryCat Health Foundation approving Dr. Pedersen’s studies, not only wouldn’t we be on the right path for kittens, but no one likely would also have considered Remdesivir for human use, which has contributed to save countless thousands of lives of humans around the globe ill with COVID-19. I once had the opportunity to personally tell Dr. Anthony Fauci, “cats have saved the world.”

Remdesivir can now be used by veterinarians, perfectly legally, off-label. Still, the problems are significant practical issues, availability of the drug; prohibitive cost and even a lack of clarity regarding cat dosages (though other nations appear to have figured it out). 

One option, which is now common in other countries, has been a compounded tuna-flavored pill from the Gilead Remdesivir formula by Bova Labs in the UK. While the Chinese products continue to be used worldwide, the Bova chewable has been prescribed in the UK, Australia, New Zealand and elsewhere. And, as of June 1, in the United States, manufactured by New Jersey based Stokes Pharmacy.

Adding to the intrigue, Stokes founder and CEO Michael Tursi told me that to be clear this is Gilead’s compound. However, he never received Gilead’s permission to use the formula, or even had his attorneys approach their attorneys. Afterall, this is Gilead’s patent.

Also, in a statement from the U.S. FDA, they question the legality of what Stokes is doing regarding encouraging prescriptions of compounded products; however, because the need is so real, they’re looking the other way. 

One upside is veterinary professionals may feel more comfortable recommending a drug from a U.S. based company, where there is open and trusted communication when compared to the Chinese sources.

Sometimes if the Chinese product didn’t appear in the mail, cat parents would have to work the Internet to find someone who lives near with the drug – and they could meet up somewhere nearby. This event hopefully no longer occurs with Stokes.

Having said that, many feline veterinarians suggest that some kittens – particularly the sickest – hugely benefit from the online available injectable, which appears to be more potent, until they’re at a point when the Stokes Pharmacy product can be used. 

Also, the Chinese products online have come down in price, making Stokes (as of this writing) greatly more expensive (though some pet insurance companies will cover the Stokes treatment).

Meanwhile, as Dr. Pedersen said all along, ultimately a cocktail of drugs may be needed to solve FIP. Other drugs are being studied, many of those funded by the EveryCat Health Foundation. Ultimately, the goal may be a vaccine to prevent kitties from getting the feline coronavirus in the first place. And all of this could once again benefit human health.

Lots of drama and making for that Netflix special.