Cutaneous lesions and clinical outcomes in five cats after frunevetmab injections

Abstract

Case series summary This case series describes five cats with cutaneous adverse events after subcutaneous administration of frunevetmab, a felinised anti-nerve growth factor monoclonal antibody, including histopathological findings in one case. All cats displayed moderate to severe pruritus resulting in self-trauma to the neck and/or head, causing lesions ranging from superficial dermatitis to alopecia and ulcerations. There were no reactions at the injection sites. In one cat, clinical signs developed after the second frunevetmab dose the cat received, with no reaction noted after the first dose. For the remaining cats, clinical signs were observed after their first dose of frunevetmab. The onset of the first episode of pruritus and self-trauma was 3–18 days after the most recent frunevetmab injection. Three cats had one or more additional frunevetmab injections after the original adverse event and all had subsequent reactions. Subsequent reactions were either similar in time frame or occurred more rapidly, with similar or more severe pruritus compared with the original reactions. Treatments and outcomes varied between cases. Relevance and novel information Frunevetmab is a novel, monthly injectable monoclonal antibody for the management of pain associated with osteoarthritis in cats. This is the first published report detailing the nature of cutaneous adverse events associated with this treatment, and the first report of the histopathological findings.

2024 ISFM and AAFP consensus guidelines on the long-term use of NSAIDs in cats

“… 109 Adverse effects can include dermatitis, alopecia and pruritus. 12 , 110 Similar to NSAIDs, anti-NGF mAbs are recommended as first-line treatments for DJD/OA in cats and dogs according to pain management guidelines from the WSAVA and American Animal Hospital Assocation. 2 , 111 Long-term studies (beyond 6 months) and studies investigating the safety of frunevetmab with concurrent NSAIDs and other medications, and in the face of comorbidities, are still needed in cats.…”