Severe paradoxical generalized pustular psoriasis induced by adalimumab biosimilar successfully treated with brodalumab.

Paradoxical psoriasis is a rare but increasingly recognized adverse effect of anti-tumor necrosis factor-α (TNF-α) therapy, characterized by the onset or exacerbation of psoriatic lesions in patients treated for other immune-mediated conditions. We report the case of a 47-year-old woman with chronic plaque psoriasis who developed severe generalized pustular psoriasis (GPP) after six months of treatment with an adalimumab biosimilar. Given the extent and severity of the eruption and following inadequate response to previous conventional therapies, the patient was treated with brodalumab, an interleukin-17 receptor A (IL-17RA) inhibitor. Rapid and complete remission of both pustular and plaque psoriasis was achieved and maintained for over 60 weeks. This case supports the efficacy of IL-17 pathway blockade in managing paradoxical GPP and highlights the importance of prompt recognition and appropriate therapeutic switching in severe biologic-induced psoriasis.