A Breakthrough in FIP Treatment for Cats: What Every Pet Owner Needs to Know
By: Dr. Katie Vance
Published January 1, 2024
With the evolution of veterinary medicine, comes a new treatment that has completely altered the way we are able to manage a previously fatal disease. This month we are discussing the developments in treatment of feline infectious peritonitis (FIP). FIP is caused by a mutation in feline coronavirus, which is a virus that is primarily spread through fecal-oral contact. The majority of cats infected with feline coronavirus do NOT go on to develop FIP. However, about 10% of cats infected with feline coronavirus will go on to mutate the virus. The body’s inflammatory response to the mutated virus goes on to cause FIP.
There are 2 forms of FIP including the wet (effusive) form and dry (non-effusive) form. The wet form is more rapidly progressing and is characterized by fluid buildup in the abdomen (ascites) and/or chest (pleural effusion). The dry form causes granulomatous inflammation in the affected organs such as eyes, brain, liver, kidneys and lymph nodes.
There are 2 forms of FIP including the wet (effusive) form and dry (non-effusive) form. The wet form is more rapidly progressing and is characterized by fluid buildup in the abdomen (ascites) and/or chest (pleural effusion). The dry form causes granulomatous inflammation in the affected organs such as eyes, brain, liver, kidneys and lymph nodes.
The Game-Changer: Antiviral Medications
Historically, FIP has been a fatal disease where we have only been able to manage symptoms supportively. In recent years, an antiviral drug called GS-441524 has become available in other countries such as the UK and Australia for treatment of FIP. Because this drug was not available in the US, pet owners with FIP cats have turned to black market purchase of the medication via Facebook groups online. Fortunately, as of June 2024, Stokes Pharmacy is compounding GS-441524 into an oral formulation that is available in the US. Although this medication is still not approved by the FDA, veterinarians can now prescribe the compounded version of GS-441524.
The typical treatment course is 12 weeks. The goal of the treatment is to stop the virus from replicating, allowing the immune system to regain control and heal the affected organs. Most cats will begin to show signs of improvement within the first 1-2 weeks, with reduced fever, increased appetite, and improved energy levels.
The typical treatment course is 12 weeks. The goal of the treatment is to stop the virus from replicating, allowing the immune system to regain control and heal the affected organs. Most cats will begin to show signs of improvement within the first 1-2 weeks, with reduced fever, increased appetite, and improved energy levels.
Success Rates & Prognosis
One of the most encouraging aspects of this new FIP treatment is its high success rate. Studies suggest that about 85-90% of cats with FIP show positive responses to treatment, and many go on to live full, healthy lives after completing the regimen. This is a remarkable improvement over the previously bleak outlook for FIP patients.
However, success isn’t guaranteed. Certain forms of FIP such as those affecting the CNS or eyes, may not respond as well to treatment.
However, success isn’t guaranteed. Certain forms of FIP such as those affecting the CNS or eyes, may not respond as well to treatment.
Cost & Accessibility
While the advent of antiviral medications for FIP has revolutionized treatment options, the cost can still be a barrier for some pet owners. The medication itself, coupled with veterinary monitoring involved, can be expensive and cost prohibitive. However, many owners find the investment worthwhile, especially when they see their cat improve from a once-terminal condition.
