Written by Alicia Hughes
As someone who has faced FIP with 3 of my own babies, unfortunately I’ve come to learn far more about this disease than I’d ever hoped to know. I hope to be able to help spread awareness of this wretched virus and the options available to any cat-parents who are faced with this dreaded diagnosis.
Prior to October 9, 2018, I’d never heard of FIP before, despite having cats for 40+ years. It was on that day that my sweet little Lily was diagnosed with and died of wet FIP at only 12.5 weeks of age. Her brother Jack would later be diagnosed with dry/neurological FIP and pass away 2 days shy of his 8 month birthday. The same day that Jack died, March 15, 2019, the anti-viral known as “GS441”, the cure for FIP, became widely available in the black market. One day too late to save my baby boy.
WHAT IS FIP?
If you’re not familiar with Feline Infectious Peritonitis, it is a virulent virus that occurs when the otherwise benign Coronavirus mutates, either due to an immune deficiency or a genetic predisposition. Nearly every cat in the world is exposed to the benign Coronavirus (FCoV), but 90-95% will clear the virus with a short bout of diarrhea, cold-like symptoms or no symptoms at all. In 5-10% of those cats, the virus goes thru a sequence of mutations that essentially tricks the white blood cells into spreading the virus rather than fighting it.
The benign FCoV is highly contagious and is spread among cats via feces to oral route, and it is currently believed that a mother cat can transmit FCoV to her babies via the placenta. Cats can carry FCoV for days, weeks, or even years without ever developing FIP. Cats may also be chronic or intermittent shedders of FCoV and never display any symptoms or go on to develop FIP. In fact, the vast majority of cats will never suffer the mutation into FIP. For the 5-10% who will progress from FCoV to FIP, once the mutation has occurred, the virus is not horizontally transmissible nor is it contagious, and the FIP cat will no longer be shedding FCoV in its feces.
When cats have no immune response to FCoV, they develop the wet form of FIP, which is characterized by a vasculitis that allows fluid to build up in the abdomen (ascites), around the lungs (pleural effusion), and/or around the heart (pericardial effusion). Early symptoms include a high and persistent fever, inappetence, lethargy, and in the case of ascites, a pot-bellied appearance that feels like a water balloon. When pleural effusion is present, the cat’s breathing may sound congested or otherwise labored, typically with open-mouthed breathing. In the case of a pericardial effusion, the cat may develop an acute heart murmur, increased heart rate, or have a clear watery nasal discharge.
Wet FIP is the simplest of all forms to diagnose, although still far from perfect.The cat’s history is considered, e.g. cats from breeders, catteries, shelters or anywhere where numerous cats are living in close quarters are at the highest risk. The most common age for FIP is under 2 years, or over 8 years, although it can strike at any time. The vast majority of FIP cats are in the 5-9 month range, presumably because this is typically the age when several stressors occur. Cats and kittens who have recently been adopted/rehomed, vaccinated, or spayed/neutered are at a higher risk because these common stressors disrupt and weaken the immune system which, coupled with concurrent exposure to FCoV, creates the perfect storm that is FIP.
In addition to a patient history and physical exam, a CBC and Chemistry panel are usually run. With wet FIP, classic markers are typically present, which include high white blood cells, high TBIL, high neutrophils, high protein, low red blood cells (non-regenerative anemia), low albumen, and high globulin. Typically a fluid sample is drawn and may be observed for color and texture, or may be sent out for a PCR. Often a simple inspection of the fluid is enough for a vet to make the diagnosis. Fluid that is straw or honey colored and sticky is a clear indicator of FIP, though fluid of a different color or texture does not rule out FIP. If a PCR is sent out, a positive result is a conclusive diagnosis; however, a negative result does not rule out FIP since there is a 30% chance of a false negative.
If the cat has a partial immune response to FCoV, he or she will develop Dry FIP. This form is much more difficult to detect and diagnosis, because it does not follow the same pattern from cat to cat. The dry form is characterized by lesions and granulomas on the cat’s organ(s), and the virus may end up in any or all organs, depending on how it travels thru the cat’s system. Outward symptoms will also depend on which organ(s) are affected. The most common early symptoms include a low-grade, persistent fever, inappetence, lethargy, and third eyelid protrusion, all of which are fairly non-specific. Other symptoms may include anemia, jaundice, dehydration, diarrhea or vomiting. Again, fairly non-specific. Vets will start the diagnosis process the same as with wet FIP, by evaluating the cat’s history, symptoms, CBC and Chemistry panel. The classic markers seen in the labs with wet FIP may or may not be present with the dry form. An ultrasound is recommended to look for thickening of the GI tract, enlarged mesenteric lymph nodes, free fluid around kidneys, enlarged organs, lesions or granulomas on organs. Tissue samples may be sent out for immuno-staining but more often than not, this isn’t necessary if the classic markers are present. Immuno-staining, like every other diagnostic for FIP, can also yield a false negative so it’s not 100% conclusive.
OCULAR AND NEURO FIP
Ocular and/or neurological symptoms can accompany either the wet or dry form, and indicate a more advanced stage of the virus. Once the virus crosses the blood/eye barrier or the blood/brain barrier, it usually progresses quickly.
Ocular symptoms may include uveitis, keratic precipitates, aqueous flare, or retinal vessel cuffing may be present.
If the virus has affected the central nervous system or brain, neurological symptoms may include ataxia, tremors, seizures, or nystagmus (darting eyes).
There are diagnostics available, e.g. PCR on aqueous fluid of the eye or spinal fluid; however, these procedures are rather invasive and given that they are not 100% accurate or conclusive, most people decline to run these tests.
FIP is technically still a death sentence, but THERE IS A CURE. Vets are not legally allowed to prescribe Gs441 because it is not FDA approved. Some are not even aware that it’s readily accessible, while others openly refer their patients to the FIP Warriors group for help locating the medication. More and more vets are becoming aware, following an article about the FIP Warriors that was published in Veterinary Info News (VIN) in August 2019.
GS441: The Myths and the Facts
GS441524 is a nucleoside analog that cures FIP by acting as an alternative substrate and RNA-chain terminator of viral RNA dependent RNA polymerase. In layman’s terms, GS441 interjects itself into the chain reaction of the virus, stops it from replicating, and cures the cat of FIP.
So why isn’t this miracle cure available at the vet’s office??? The GS441524 molecule was patented by Gilead Science for use in the human ebola drug, Remdesivir. In 2017, Dr Niels Pedersen was given access to the molecule for FIP research. The various field studies proved that GS441 cured 25 out of 26 cats with naturally occurring FIP. Moreover, it cured all forms of FIP, including the toughest forms, ocular and neuro FIP. As of today, the 25 cats that survived the field study are alive and thriving, with no recurrence of the virus. But the fact that GS441 could cure our cats was never the intent of Gilead Science. In fact, they don’t even have a veterinary division so they will never produce this medication for cats. In September 2019, field studies of Remdesivir for the human ebola virus failed and Gilead withdrew their FDA application. Gilead is now researching alternative human applications for the molecule. If and when Gilead creates a human anti-viral drug with this molecule AND gets FDA approval for it, only then will they consider releasing the veterinary-use patent to another manufacturer that has a veterinary division. This could be years, possibly a decade, before it comes to fruition. Meanwhile, thousands of cats are dying needlessly while the cure sits on Gilead’s shelf.
The raw chemical compound for this drug is readily available from several bio-labs and the instructions for the diluent are thoroughly detailed in the GS441524 Safety & Efficacy Study. It’s not exactly something a layperson could whip up in their kitchen, but it doesn’t require a PhD in chemistry either. It didn’t take long once the field study was released before there were several China-based labs and universities that were manufacturing black market versions of GS. While these drugs are unregulated and non FDA approved, they are not illegal. They are discussed quite openly online, in veterinary publications, at FIP seminars and symposiums, etc. One of the manufacturers recently participated as a vendor at the NYC Vet Show.
GS is currently available in 2 forms: an injectable and an oral capsule/tablet. With either form, the treatment protocol involves 84 days of daily dosing, followed by an 84 day observation period. The daily dose depends on the weight of the cat, the form of FIP, and the concentration of the medication. During the initial treatment period, it’s recommended to recheck labs at 4, 8 and 12 weeks, and the same during the observation period. If there is no relapse during the 84 day observation period, the cat is deemed cured. If there is a relapse, the cat will need to extend treatment further than the initial 12 weeks. Overall, the success rate for curing FIP with GS is in the 90 percentile. The cost of treatment ranges from $700 – $10,000, again depending on the cat’s weight, type of FIP and the brand of GS used. The vast majority of treatment falls into the $1500-3000 range over the course of 12 weeks, excluding diagnostics and/or vet exams. Pet insurance cannot cover the GS due to it being non-FDA approved; however, the insurers will cover all other FIP-related expenses.
There are no significant side effects with GS. With the injectable form, the diluent is acidic so many cats do develop minor sores at the injection sites, the vast majority of which heal on their own without complication or intervention. Occasionally, we’ve seen some sores that got infected and required a course of antibiotics. With the oral form, the capsules may cause vomiting,especially early on in the course of treatment. As far as long term effects, we can only go back as far as the field studies in 2017, from which there have been none reported.
A HAPPY ENDING
In the summer of 2019, I was finally ready to adopt again after grieving the loss of my 2 FIP angels. My Siberian Forest Cat Petey came home on May 25th and was the picture of health and perfection. A month later, I fell in love with and adopted a DLH rescue kitten who had been hand raised by a vet-tech after his litter was found abandoned The 2 boys bonded immediately and were inseparable. Everything was great until they went to the vet on July 23rd for a wellness exam and each got their FELV vaccine.
Two weeks later, August 6th, Petey missed a meal which was completely unlike him. He was 5.5 months old at the time and would normally eat his body weight in food if I’d let him. He went to the vet that afternoon, fearing the worst, but my vet assured me that I was having FIP Paranoia. His fever was 104F and his CBC and Chem panel looked fairly normal except for extremely high WBC and neutrophils. He was diagnosed with a bacterial infection, given a Convenia injection and sent home. Whew, it was nothing! But no, that would change soon enough.
The next morning, his fever was 106.5, he again refused food and water, and he was extremely lethargic. I admitted him into the hospital and for the following 4 days, despite 3 antibiotics, IV fluids, nutritional support, and cooling pads, he got progressively worse to the point where he was just laying face down in his litter box and he was not expected to survive the week. On Aug 11th, the dreaded phone call came. Petey had palpable fluid in his abdomen. A new CBC and chem panel were run, and abdominal fluid was sent out for a PCR. All of the classic markers were present and he was diagnosed with wet FIP.
After Lily and Jack died, I’d stayed involved with FIP Warriors largely because I found it cathartic to help other cats beat this monster. I never imagined I’d be needing the support of the group first hand again. Thankfully though, because of my involvement I knew that experimental GS from China was readily available. I told my vet that Petey was going to try black market GS and that I fully understood if she could not be involved with his treatment, but her response shocked me. “If there’s anything we can do to save him, I’m not going to let this baby die needlessly. How soon can you be back with some GS?” I found some that was located about 2 hours from home, jumped in my car and drove to NY that night to get it.
He got his first dose the next day. Within 12 hours, his fever broke and his temp was normal again at 102. After dose #3, he ate the full plate of food that was left for him during the night and was crying for more the following morning when the hospital staff arrived. After his 5th dose, he looked and acted like a perfectly healthy kitten and he was discharged home, where he continued to do amazingly well. We continued to go to his vet every day to check his weight, temp, and administer his injection. Petey’s entire team was 110% supportive and thrilled with his miraculous progress.
On day 25 of treatment, his CBC and chem panel showed tremendous improvement, but he still had some liver and kidney values that were irregular. We stayed the course with his daily injections and on day 65 of treatment, he had a new CBC, chem panel and ultrasound done. The results of all diagnostics were absolutely flawless, with no trace of FIP whatsoever!
After consulting with Dr Niels Pedersen, we decided that Petey would be neutered during his GS treatment. He’d matured right around the mid-point of treatment and was becoming extremely aggressive and dominant. He was neutered on day 72 and continued his injections for the remaining 12 days, the theory being that he’d be protected by GS while his immune system recovered from surgery.
He finished his treatment on November 3rd and I’m happy to say that he is officially FIP-free! Today he is a perfectly healthy, crazy, 8.5 month old kitten with boundless energy, a voracious appetite, and an endless desire for belly-rubs. The 84-day journey wasn’t easy…but giving my baby boy the chance at a long healthy life was totally worth it!
- FIP Warriors (facebook) – Provides assistance with diagnosis of FIP and treatment options, including GS
- zenbycat.org – The founder is the dad to one of the original survivors in Dr P’s first study with GC376. Zen By Cat is a non-profit that raises money for FIP research and cure thru donations and affiliate sales of cat related merchandise.
- fiptreatment.com – My website, which includes current news about GS and FIP, treatment options, supportive care advise for FIP cats, etc.
- sockfip.org – Dr Pedersen’s website that chronicles his 50+ years of FIP research