{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T14:22:07Z","timestamp":1787062927526,"version":"build-2736575974"},"reference-count":45,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,8,9]],"date-time":"2023-08-09T00:00:00Z","timestamp":1691539200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Feline infectious peritonitis (FIP), caused by feline coronavirus (FcoV), is considered one of the most enigmatic diseases in cats. Developing effective drugs for FIP is crucial due to its global prevalence and severity. In this study, six antiviral drugs were tested for their cytotoxicity, cell viability, and antiviral efficacies in Crandell-Reese feline kidney cells. A cytotoxicity assay demonstrated that these drugs were safe to be used with essentially no cytotoxicity with concentrations as high as 250 \u00b5M for ruxolitinib; 125 \u00b5M for GS441524; 63 \u00b5M for teriflunomide, molnupiravir, and nirmatrelvir; and 16 \u00b5M for ritonavir. GS441524 and nirmatrelvir exhibited the least detrimental effects on the CRFK cells, with 50% cytotoxic concentration (CC50) values of 260.0 \u00b5M and 279.1 \u00b5M, respectively, while ritonavir showed high toxicity (CC50 = 39.9 \u00b5M). In the dose\u2013response analysis, GS441524, nirmatrelvir, and molnupiravir demonstrated promising results with selectivity index values of 165.54, 113.67, and 29.27, respectively, against FIPV. Our study suggests that nirmatrelvir and molnupiravir hold potential for FIPV treatment and could serve as alternatives to GS441524. Continued research and development of antiviral drugs are essential to ensure the well-being of companion animals and improve our preparedness for future outbreaks of coronaviruses affecting animals and humans alike.<\/jats:p>","DOI":"10.3390\/vetsci10080513","type":"journal-article","created":{"date-parts":[[2023,8,9]],"date-time":"2023-08-09T10:21:50Z","timestamp":1691576510000},"page":"513","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Comparative Evaluation of GS-441524, Teriflunomide, Ruxolitinib, Molnupiravir, Ritonavir, and Nirmatrelvir for In Vitro Antiviral Activity against Feline Infectious Peritonitis Virus"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6441-8930","authenticated-orcid":false,"given":"Subarna","family":"Barua","sequence":"first","affiliation":[{"name":"Department of Pathobiology, Auburn University College of Veterinary Medicine, Auburn, AL 36830, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bernhard","family":"Kaltenboeck","sequence":"additional","affiliation":[{"name":"Department of Pathobiology, Auburn University College of Veterinary Medicine, Auburn, AL 36830, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yen-Chen","family":"Juan","sequence":"additional","affiliation":[{"name":"Department of Pathobiology, Auburn University College of Veterinary Medicine, Auburn, AL 36830, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard Curtis","family":"Bird","sequence":"additional","affiliation":[{"name":"Department of Pathobiology, Auburn University College of Veterinary Medicine, Auburn, AL 36830, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7874-8340","authenticated-orcid":false,"given":"Chengming","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Pathobiology, Auburn University College of Veterinary Medicine, Auburn, AL 36830, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1136\/vr.146.15.419","article-title":"Long-term impact on a closed household of pet cats of natural infection with feline coronavirus, feline leukaemia virus and feline immunodeficiency virus","volume":"146","author":"Addie","year":"2000","journal-title":"Vet. 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