Objectives Interleukin-17 (IL-17) contributes to the pathogenesis of psoriasis. Secukinumab, ixekizumab, and brodalumab are monoclonal antibodies anti-IL-17 antibodies, approved for the treatment of moderate/severe plaque psoriasis.

The aim of the study was to describe the effectiveness and safety of anti-IL-17 agents in moderate/severe plaque psoriasis in clinical practice. We also analysed anti-IL-17 therapies’ survival, dose adjustment, and clinical patients’ factors associated with their effectiveness and safety.

Methods A retrospective, longitudinal study was conducted at a tertiary hospital. We included patients with moderate/severe psoriasis treated with anti-IL-17 agents. The effectiveness was evaluated with Psoriasis Area and Severity Index (PASI) score and safety through the adverse drug reactions (ADRs) collected.

Results 38 patients were studied (median age=47.4 years, 71.0% male). The mean number of biological therapies that patients received was 2.6, and anti-IL-17 therapy was the first biological therapy for 36.8% of patients. The median years in treatment were 2.5 (95% CI 1.95 to 2.98) for secukinumab, 1.2 (95% CI 0.36 to 1.47) for ixekizumab, and 0.7 (IQR 0.71) for brodalumab. The median PASI score after 6 months of treatment was 0 (IQR 0) and 85.3% of patients achieved a PASI of 90 (84.0% with secukinumab, 87.5% with ixekizumab, and 100% with brodalumab). Dose adjustment was associated with the line of treatment (p=0.034 for naïve patients), age (p=0.044 for younger patients), and concomitant pathologies (p=0.015 without more diseases).

24 patients suffered from ADRs, mainly infections of the upper respiratory tract, and there were no statistically significant differences between the three therapies.

Conclusions Anti-IL-17 agents constitute an effective treatment for patients with moderate/severe plaque psoriasis and for longer. Dose reductions were associated with fewer lines of treatment, younger patients and absence of concomitant pathologies. ADR were minor and similar among the anti-IL-17.