Onset of vitiligo during bimekizumab treatment for psoriasis

Psoriasis is an inflammatory skin disorder characterized by epithelial hyperplasia and infiltration of inflammatory cells. Several immunological therapies have been developed for its treatment, including IL-17 inhibitors such as secukinumab, ixekizumab and bimekizumab. The safety profile of IL-17 inhibitors includes infectious diseases, gastrointestinal disorders, headaches, and cutaneous conditions such as eczema. Here, we report the first case of vitiligo, a depigmenting skin disorder characterized by the selective loss of melanocytes, occurring during treatment with bimekizumab. This case involved a 42-year-old man who achieved complete skin clearance of psoriasis plaques under bimekizumab therapy. After 11 months of treatment, he developed vitiligo patches on his face. These lesions resolved following discontinuation of bimekizumab, minipulse therapy and ruxolitinib cream application. Vitiligo occurrence has been previously observed with other IL-17 inhibitors, including secukinumab and ixekizumab (11 other cases). Although IL-17 is believed to play a role in the pathophysiology of vitiligo, its exact mechanism remains unclear. Paradoxal vitiligo may represent a class effect of IL-17 inhibitors, particularly in patients with psoriasis. This potential adverse effect should be considered, especially in patients with a personal or family history of vitiligo or other depigmentation disorders. Interestingly, stability or even repigmentation has been observed in patients who continued anti-IL-17 therapy, regardless of whether they received symptomatic treatment. Given the efficacy of anti-IL17 inhibitors in psoriasis, the risk-benefit balance should be carefully discussed in this context.