Predictors for the effectiveness of 75 mg risankizumab in treating psoriasis—A real‐word evidence from a 52‐week retrospective study

Abstract In the registration trial of risankizumab for patients with moderate‐to‐severe psoriasis in Japan, similar Psoriasis Area Severity Index (PASI) responses were observed for 75 mg or 150 mg risankizumab at most time points up to 52 weeks, except for PASI 100 at week 16. The use of 75 mg risankizumab offers an attractive option considering the high cost of risankizumab. However, it is unknown whether patients with mild‐to‐moderate psoriasis respond similarly, and the efficacy data of non‐Japanese patients is also lacking. We retrospectively included 30 consecutive Chinese patients receiving half‐dose (75 mg) risankizumab as scheduled up to 52 weeks. Compared with biologic‐experienced group, biologic‐naive group had a significantly higher PASI 50/75/90/100 achievement ( p = 0.0098/0.0039/0.0016/0.0054) at week 52. PASI 50/75/90/100 curves in biologic‐naive group ( p = 0.0117/0.0239/0.0143/0.0269) were also significantly higher when analysed generalized estimating equations (GEE) model. Though there was no statistically significant difference in terms of PASI 50/75/90/100 responses at any time points between those with body weight ≦ 65 kg and those >65 kg, a tendency of secondary failure was noted in those >65 kg from week 40 onwards. Patients who were both biologic‐naive and weighed ≦ 65 kg achieved sustained PASI 50/75/90 responses from week 16/28/40 onwards, respectively, indicating that they could be considered as potential candidates for 75 mg risankizumab. Though PASI 75 curve in patients without diabetes mellitus (DM) surpassed that in patient without DM, curves of other parameters did not reach significance when analysed by GEE model. There was no HBV, HCV or TB reactivation, nor other new safety signals during the 52‐week observational period. Providing risankizumab with flexible dosing options is beneficial in clinical practice considering the high cost of this medication.