Not that long ago, feline infectious peritonitis (FIP) was considered invariably fatal in cats, with no effective treatment options until 2018, when an antiviral drug GS-441524 was shown to successfully treat FIP. This drug is not widely available, but a closely related drug, remdesivir, became available as a compounded medication in NZ during the Covid pandemic. Vets have been using remdesivir to treat FIP, but there has not been any research on how effective it is when given orally (as the injectable form can be painful and expensive), or any research specific to NZ. This is where Dr Kelsey Renner of the Animal Referral Centre in Auckland and her colleagues come in: they conducted a study, funded by Healthy Pets, in which 29 cats with FIP were treated with oral remdesivir. Their work showed that oral remdesivir at a dose of 30mg/kg once daily is effective in treating the effusive form of FIP, with 25 cats (86%) in total entering remission and surviving beyond 6 months. Five cats experienced relapses of the disease, of which 4 had the non-effusive (‘dry’) form, suggesting that cats with the non-effusive form may need higher doses or more frequent administration of remdesivir. This study represents an important contribution to how cats with FIP in NZ and worldwide are treated, and the first of Kelsey’s 2 papers from this study is available open access at https://journals.sagepub.com/doi/10.1177/1098612X251335189 if you’re keen to know more.