Companion Animal Welfare

Companion Cat: FIP Antiviral Treatment Progress

Feline infectious peritonitis (FIP), once universally fatal, can now be treated successfully with antiviral drugs, representing a landmark welfare advance for cats.

Key Facts

FIP is caused by a mutant form of feline coronavirus causing systemic vasculitis
Before 2019, FIP was considered universally fatal with no effective treatment
GS-441524 and molnupiravir are nucleoside analogues that have shown 85-95% remission rates in trials
Treatment requires 84 days of daily oral or injected medication
UK veterinary surgeons can now prescribe licensed FIP treatment, making access more straightforward

Welfare Considerations

FIP caused inevitable, often prolonged death in affected cats, with progressive weight loss, fever, and fluid accumulation causing significant suffering. The development of effective antiviral treatment represents one of the most significant welfare advances in veterinary medicine in recent decades. Cats that previously faced certain death now have an 85-95% chance of full remission with treatment.

What You Can Do

Seek veterinary assessment immediately if your cat shows signs consistent with FIP
Discuss antiviral treatment options with your vet - licensed products are increasingly available
Join FIP support communities to access information and support during treatment
Share information about FIP treatment options with other cat owners
Support research continuing to improve FIP treatment access and affordability