Paradoxical psoriasis induced by IL-17 inhibitors: a case series of patients with axial spondyloarthritis and a systematic literature review.

Following the market authorization of interleukin (IL)-17 inhibitors, a growing number of cases of IL-17 inhibitor-induced paradoxical psoriasis (PsO) have been reported. Our objectives were to present two cases of IL-17 inhibitor-induced paradoxical PsO and to systematically review the literature for similar cases, summarizing and presenting the relevant data. A systematic literature review of previously presented cases of paradoxical PsO induced by IL-17 inhibitors was conducted. We presented two patients with axial spondyloarthritis (axSpA) and paradoxical PsO induced by secukinumab (SEC). One patient's psoriatic lesions responded well to adjuvant topical treatment, while the other patient required a combination of topical treatment and cyclosporine Α for successful treatment. SEC was continued in both cases. We also identified 35 patients with IL-17 inhibitor-induced paradoxical PsO in the literature review. The most frequent types of paradoxical PsO were palmoplantar pustular and plaque PsO, while the median latency period was 11 weeks. Approximately one-third of patients continued IL-17 inhibitor treatment with adjunctive therapy, primarily topical, which produced satisfactory results in most patients. Almost two-thirds of the patients discontinued the IL-17 inhibitor, with the majority of patients switching to another biological agent with a different mechanism of action or initiating other systemic antipsoriatic treatments, resulting in mainly satisfactory outcomes. Therefore, paradoxical PsO induced by IL-17 inhibitors appears to respond well in both patients who continue IL-17 inhibitors with adjunctive treatment and those who discontinue IL-17 inhibitors while switching to a different class of biological agent or initiating other systemic antipsoriatic treatments.