2024-04-16
Antiviral therapy using the adenosine nucleoside analog GS-441524 in cats
Feline infectious peritonitis (FIP) is caused by a mutant feline enteric coronavirus biotype. The resulting FIP virus (FIPV) in the case of the non-fusion form commonly causes pathologies of the central nervous system (CNS) and the eyes. More than 95% cats with FIP succumb to the disease several days to months after diagnosis, despite various historically used treatments. Recently developed antiviral drugs have shown promise in the treatment of non-neurological FIPs, but data on the treatment of neurological cases of FIP are limited. Four cases of naturally occurring FIP with CNS involvement were treated with the antiviral nucleoside analog GS-441524 (5-10 mg / kg) for at least 12 weeks. Cats were monitored continuously by physical, neurological and ophthalmological examinations. One cat underwent magnetic resonance imaging (MRI), cerebrospinal fluid (CSF) analysis, including FCoV titer, RT-PCR, and ophthalmic examination using Fourier optical coherence tomography and in vivo confocal microscopy (IVCM). All cats responded positively to treatment. The three cats are still alive (528, 516 and 354 days after the start of treatment) with normal results of physical and neurological examinations. One cat was euthanized 216 days from the start of treatment after relapses after primary and secondary treatment. In 1 case, the cure of the disease was determined on the basis of normalization of MRI and CSF findings and examination of cranial and caudal segment disease using ocular imaging methods. Treatment with GS-441524 shows its clinical efficacy and may lead to clearance and long-term regression of neurological FIP. The doses required for CNS disease may be higher than the doses used for non-neurological FIPs.