{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,27]],"date-time":"2026-10-27T20:53:12Z","timestamp":1793134392545,"version":"4.5.0"},"reference-count":51,"publisher":"SAGE Publications","issue":"4","license":[{"start":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T00:00:00Z","timestamp":1773100800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/"},{"start":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T00:00:00Z","timestamp":1773100800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/journals.sagepub.com\/page\/policies\/text-and-data-mining-license"}],"funder":[{"name":"Small Animal Foundation, Vetsuisse Faculty, University of Zurich","award":["F-53130-45-01"],"award-info":[{"award-number":["F-53130-45-01"]}]},{"name":"UZH Scientific Research Grant","award":["F-53130-44-01"],"award-info":[{"award-number":["F-53130-44-01"]}]},{"name":"Swiss Association for Small Animal Medicine","award":["SVK-ASMPA, F-53420-10-01"],"award-info":[{"award-number":["SVK-ASMPA, F-53420-10-01"]}]},{"name":"UZH Global Strategy and Partnerships Funding Scheme","award":["K-53420-02 01"],"award-info":[{"award-number":["K-53420-02 01"]}]}],"content-domain":{"domain":["journals.sagepub.com"],"crossmark-restriction":true},"short-container-title":["Journal of Feline Medicine and Surgery"],"published-print":{"date-parts":[[2026,4]]},"abstract":"<jats:sec>\n                    <jats:title>Case series summary<\/jats:title>\n                    <jats:p>Fatal feline infectious peritonitis (FIP), caused by feline coronavirus (FCoV), can now be cured with GS-441524. Only a few unexpected clinical and laboratory observations have been reported with treatment, including lymphocytosis, eosinophilia and long-term persistence of abdominal lymphadenomegaly. Yet immune overstimulation associated with FIP might have negative long-term consequences. This report describes four cases of large-cell lymphoma (LCL) arising within 2 years of FIP diagnosis and successful treatment with legally sourced oral GS-441524 (15\u2009mg\/kg q24h), representing an incidence of 2.0% (n\u2009=\u20094\/202) in a large treatment cohort. At LCL diagnosis, two cats were aged under 2 years, one was aged 8 years and one was aged 13 years. All cats showed weight loss, three had hyporexia and two had chronic vomiting; all tested negative for feline leukaemia virus and feline immunodeficiency virus. LCL was diagnosed by histology (n\u2009=\u20093) or cytology (n\u2009=\u20091) at 81, 365 (n\u2009=\u20092) and 595 days after FIP diagnosis\/treatment start. The cats died a median of 15.5 days after LCL diagnosis. Neither a high FCoV viral load nor FCoV antigen, as determined by semi-quantitative RT-PCR and immunohistochemistry, respectively, was detected in any of the available samples. PCR for antigen receptor rearrangements revealed a monoclonal B-cell population in two cats, supporting a diagnosis of large B-cell lymphoma.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Relevance and novel information<\/jats:title>\n                    <jats:p>The incidence of LCL reported here among cats in remission from FIP after legally sourced oral GS-441524 treatment is remarkably high compared with the general feline population. LCL should be considered a potential \u2018long-FIP syndrome\u2019 and\/or a long-term complication after GS-441524 treatment. The pathogenesis of LCL in this context requires further clarification.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1177\/1098612x261434629","type":"journal-article","created":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T19:20:14Z","timestamp":1773256814000},"update-policy":"https:\/\/doi.org\/10.1177\/sage-journals-update-policy","source":"Crossref","is-referenced-by-count":3,"title":["Large-cell lymphoma in four cats after successful treatment of feline infectious peritonitis with oral GS-441524: a novel clinical observation"],"prefix":"10.1177","volume":"28","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-8344-2994","authenticated-orcid":false,"given":"Katharina","family":"Buchta","sequence":"first","affiliation":[{"name":"LMU Small Animal Clinic, Centre for Clinical Veterinary Medicine, LMU Munich, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-0304-7647","authenticated-orcid":false,"given":"Sol\u00e8ne 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