Number Needed to Treat for Interleukin Inhibitors Approved for the Treatment of Moderate-to-severe Plaque Psoriasis in Italy

Background: Interleukin (IL) inhibitors achieve greater levels of efficacy than older systemic therapies. We calculated the number needed to treat (NNT) of ixekizumab compared with other IL inhibitors approved in Italy for the treatment of moderate-to-severe plaque psoriasis. Methods: The clinical efficacy was evaluated in terms of NNT, based on the results of a recent network meta-analysis (NMA) by the Cochrane Database of Systematic Reviews. The NMA investigated many systemic and biological treatments, but this analysis compared only the efficacy of the following IL inhibitors - brodalumab, guselkumab, ixekizumab, risankizumab, secukinumab, tildrakizumab and ustekinumab - for patients with moderate-to-severe plaque psoriasis. Drugs were compared and ranked according to effectiveness considering the PASI (Psoriasis Area and Severity Index) 90 score. Results: One-hundred and forty trials (51,749 patients) were included in the NMA. Considering the proportion of patients who achieve PASI90, ixekizumab showed the lowest NNT among all comparators (ixekizumab 2.01 [2.46-3.00]; risankizumab 2.05 [2.50-3-05]; guselkumab 2.16 [2.68-3.36]; secukinumab 2.40 [2.90-3.51]; brodalumab 2.61 [3.18-3.88]; ustekinumab 3.44 [4.12-4.95]; tildrakizumab 3.10 [4.15-5.59]. Conclusion: The findings show that ixekizumab is the most effective option (NNT) for the treatment of moderateto-severe plaque psoriasis.