P0705Non-infectious skin lesions occurring under ustekinumab therapy in Crohn’s disease patients: A retrospective observational multicentre GETAID study.

Abstract Background Unlike paradoxical skin reactions induced by anti-TNF agents, cutaneous adverse events under ustekinumab are uncommon. The clinical presentation, distribution, and risk factors remain poorly defined. Methods We performed a retrospective, observational, multicentre study including all patients followed between June 2015 and December 2024 in seven GETAID centres. Adults with Crohn’s disease (CD) who developed significant non-infectious cutaneous lesions while receiving ustekinumab therapy and requiring dermatological evaluation were included. Demographic and CD characteristics were collected. Skin lesions were clinically characterized by a dermatologist, and disease management, ustekinumab discontinuation, and risk factors were analysed. Results Thirty-two patients (21 women, median age: 38 years (range, 26–83) developed non-infectious cutaneous lesions while on ustekinumab. All had prior anti-TNF exposure. Ustekinumab was initiated for anti-TNF failure (74%) or intolerance (23%). Median time to lesion onset was 5.5 months (range 0–75). Forty percent had a history of atopy or psoriasis, and 65% had previously developed anti-TNF–induced dermatosis. At the time of skin lesion onset, 59% had active CD. Psoriasiform (40%) and eczematous (31%) eruptions were most frequent, followed by acneiform lesions (25%), and one case of cutaneous vasculitis. The face (43%) and trunk (40%) were most affected, followed by limbs (28%), palms/soles (21%), and rarely the scalp. Topical therapy (steroids, keratolytics, vitamin D analogues, azelaic acid, or benzoyl peroxide) was used in 88% of patients, with improvement in 70%, 50%, and 37% for eczematous, psoriasiform, and acneiform lesions, respectively. Ustekinumab was discontinued in eight patients (25%) for persistent or severe lesions (n = 4), persistent lesions with uncontrolled CD (n = 3), or active CD despite skin lesion resolution (n = 1). A prior history of paradoxical anti-TNF–induced dermatosis was associated with a higher risk of psoriasiform eruptions under ustekinumab (OR 12,0; 95% IC = 1,3-112,7 p = 0,03). Conclusion Non-infectious cutaneous lesions under ustekinumab in CD are rare, most commonly psoriasiform or eczematous. They predominantly affect the face and trunk and lead to ustekinumab discontinuation in one-quarter of cases. A history of paradoxical anti-TNF–induced skin reactions appears to be a significant risk factor. Conflict of interest: Piga, Gauthier: No conflict of interest Amiot, Aurelien: Personal Fees: Abbvie, Fresenius-Kabi, Adacyte, Tillotts pharma, Janssen, Pfizer, Biogen, AMgen, Sandoz, Takeda, Galapagos, Eli Lilly Bonnet, joelle: No conflict of interest Charlois, Anne: No conflict of interest Benezech, Alban: No conflict of interest Hebuterne, Xavier: Xavier Hébuterne reports clinical research funding from AbbVie, Abivax, Alphasigma, Arena Pharmaceuticals, Celgene, Eli Lilly, Enterome, Gilead, Janssen, InDex Pharmaceuticals, Pfizer, Roche, Salix, Sangamo, Takeda, Theravance, serving on advisory boards for AbbVie, Abivax, Arena Pharmaceuticals, Gilead, Janssen, Pfizer, Roche, Takeda, and participating in lectures and educational activities for AbbVie, Amgen, Baxter, Fresenius Kabi, Janssen, MSD, Mylan, Nutricia, Pfizer, Tillots, and Takeda. Laharie, David: Personal Fees: Board, consulting and lecture fees from Abbvie, Alfasigma, Amgen, Biocon, Celltrion, Ferring, Fresenius-Kabi, Johnson & Johnson, Lilly, MSD, Pfizer, Sandoz and Takeda Peyrin-Biroulet, Laurent: CONSULTING Abbvie, Abivax, Adacyte, Alimentiv, Alfasigma, Amgen, Apini, Banook, BMS, Celltrion, Enthera, Ferring, Fresenius Kabi, Galapagos, Genentech, Gilead, Iterative Health, Janssen, Lilly, LifeMine, Medac, Morphic, MSD, Nordic Pharma, Novartis, Oncodesign Precision Medicine, ONO Pharma, OSE Immunotherapeuthics, Par’ Immune, Pfizer, Prometheus, Roche, Roivant, Samsung, Sandoz, Sanofi, Sorriso, Spyre, Takeda, Teva, ThirtyfiveBio, Tillots, Vectivbio, Vedanta, Ventyx. LECTURE Abbvie, Alfasigma, Amgen, Biogen, Celltrion, Ferring, Galapagos, Genentech, Gilead, Iterative Health, Janssen, Lilly, Medac, MSD, Nordic Pharma, Pfizer, Sandoz, Takeda, Tillots Nancey, Stéphane: board membership and lecturing fees from Abbvie, Takeda, Celltrion Healthcare, Pfizer, Galapagos, Johnson & Jonshon, Lilly, Fresenius, Amgen, Medac, MSD.