Number needed to treat for interleukin inhibitors approved for the treatment of moderate-to-severe plaque psoriasis in Italy


  • Roberto Ravasio Health Publishing & Services Srl, Milan - Italy
  • Antonio Costanzo Dermatology, Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan and Dermatology, IRCCS Humanitas Research Hospital, Rozzano, Milan - Italy
  • Silvia Antonelli Eli Lilly Italia S.p.A., Sesto Fiorentino - Italy
  • Alessia Maiorino Eli Lilly Italia S.p.A., Sesto Fiorentino - Italy
  • Serena Losi Eli Lilly Italia S.p.A., Sesto Fiorentino - Italy



Interleukin inhibitor, Ixekizumab, Number needed to treat, Plaque psoriasis


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 moderate-to-severe plaque psoriasis.


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How to Cite

Ravasio, R., Costanzo, A., Antonelli, S., Maiorino, A., & Losi, S. (2021). Number needed to treat for interleukin inhibitors approved for the treatment of moderate-to-severe plaque psoriasis in Italy. Global and Regional Health Technology Assessment, 8(1), 53–57.



Original Research Articles


Received 2020-12-22
Accepted 2021-03-22
Published 2021-04-15


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