Real-World Discontinuation and Switching Patterns for Interleukin-Inhibitor Treatments in Patients with Moderate-to-Severe Psoriasis in Japan

Abstract Introduction Patients with moderate-to-severe psoriasis (PsO) treated with interleukin (IL)-inhibitors may require treatment modification to achieve disease control. This study evaluated discontinuation and switching of IL-inhibitors for PsO patients in Japan. Methods Japan Medical Data Center claims (1/2005–5/2022) were used to identify patients with PsO diagnosis preceding a first IL-inhibitor claim (index date) with ≥ 6 months of eligibility prior. Treatment switch (claim for another biologic) and discontinuation (gap in care ≥ 150% of the days’ supply of the preceding prescription) were assessed up to 24 months following initiation. Censored Kaplan–Meier time-to-event analyses calculated rates, and Cox proportional hazards models estimated hazard ratios (HRs) adjusting for baseline characteristics. Results The study included 1481 unique patients treated with brodalumab (BRO; n = 159), guselkumab (GUS; n = 360), ixekizumab (IXE; n = 279), risankizumab (RIS; n = 327), secukinumab (SEC; n = 366), tildrakizumab (n = 40; excluded due to limited data), and ustekinumab (UST; n = 262). At 12/24 months, 25.9%/38.6% of patients overall had discontinued their index IL-inhibitor and 13.5%/21.2% had switched to another biologic. Discontinuation at 12/24 months was lowest for RIS (11.2%/17.4%), followed by UST (17.9%/32.2%), IXE (27.0%/37.0%), GUS (29.8%/43.0%), SEC (35.6%/53.8%), and BRO (37.2%/47.2%). Switching showed a similar trend: RIS (5.7%/10.7%), UST (11.2%/19.9%), SEC (14.7%/25.7%), IXE (14.8%/21.5%), GUS (16.9%/23.2%), and BRO (19.7%/26.8%). HRs of discontinuation relative to RIS were 2.07 for UST, 2.59 for IXE, 2.70 for GUS, 3.65 for BRO, and 3.69 for SEC (all P ≤ 0.001). HRs of switching relative to RIS were 2.05 for IXE, 2.45 for GUS, 2.67 for SEC, 2.73 for UST, and 2.77 for BRO (all P ≤ 0.01). Conclusion Treatment modification of IL-inhibitors for PsO was commonly observed and could indicate insufficient disease control and/or incremental economic burden. Discontinuation and switching rates were lowest for RIS regardless of time point and adjustment for patient characteristics.