The Use of IL-17 and IL-23 Inhibitors in Swedish Clinical Practice: A Register-Based Analysis

Background: Interleukin (IL) inhibitors have made completely cleared skin achievable for many patients with moderate to severe psoriasis in clinical trial settings. Few observational studies assess treatment response in accordance with treatment goals in guidelines. Objectives: The aim of the study was to analyze the treatment response of IL-17/IL-23 inhibitors in clinical practice and the proportions of patients that reach the treatment target of the Psoriasis Area and Severity Index (PASI) < 3 and the Dermatology Life Quality Index (DLQI) ≤5. Methods: A longitudinal, observational study based on the Swedish National Registry for Systemic Treatment of Psoriasis, PsoReg. Patients using IL-17/IL-23 inhibitors with assessments of PASI, DLQI, and EQ-5D before (maximum 6 months) and after (3–12 months) initiation of IL-17/IL-23 were included. Results: In total, 333 patients using IL-17/IL-23 inhibitors were included. Eighty percent (n = 266) received IL-17 inhibitors, and 20% (n = 67) received IL-23 inhibitors. Sixty-six percent of patients reached both PASI <3 and DLQI ≤5, 23% reached one target, and 11% reached none. The mean (SD) PASI, DLQI, and EQ-5D improvements were 6.75 (6.99), 7.14 (7.97), and 0.126 (0.296), respectively. There was no statistically significant difference in outcomes between IL-17 and IL-23 inhibitor treatment groups. Conclusions: IL-17/IL-23 inhibitors are effective in clinical practice, but there is still an unmet therapeutic need in moderate to severe psoriasis.