Dermatological and gastrointestinal adverse reactions in ocrelizumab treated patients with multiple sclerosis: a case series

Background Anti-CD20 therapies are widely used in patients with multiple sclerosis (pwMS). Recognition of rare adverse reactions to these therapies is therefore important. Objectives To report dermatological and gastrointestinal adverse reactions in a single-center cohort of ocrelizumab treated pwMS. Methods Retrospective analysis conducted at a multiple sclerosis outpatient clinic of Charité – Universitätsmedizin Berlin, Berlin, Germany, between March 2020 and February 2025. Results Among 447 ocrelizumab treated pwMS, 8 (1.8%) developed dermatological adverse reactions after a median (range) of 20.5 (6-72) months following start of therapy, including lichen planus (n=2), rosacea (n=1), psoriatic arthritis (n=1), guttate psoriasis (n=1), psoriasis vulgaris (n=1), nail psoriasis (n=1) and palmoplantar psoriasis (n=1). Another 5 (1.1%) patients developed gastrointestinal adverse reactions 24 (0.25-77) months after starting therapy, including Crohn’s disease (n=1), toxic colitis (n=1), lymphocytic colitis (n=1), perforated appendicitis (n=1) and acute cholecystitis (n=1). Due to these adverse reactions, ocrelizumab was stopped in 7/13 patients. At last follow-up, adverse reactions had completely improved in 4/13, incompletely improved in 6/13, and persisted in 3/13 patients. Conclusions Clinicians should be aware of dermatological and gastrointestinal adverse reactions associated with ocrelizumab, which can develop from a few weeks up to six years after start of therapy.