Switching to Tildrakizumab 200 mg after Anti-IL-17 Failure in Moderate-to-Severe Psoriasis: A 52-Week Prospective Real-World Study

INTRODUCTION: Switching between biologic therapies is a common strategy in the management of moderate-to-severe psoriasis after treatment failure. However, prospective real-world data on switching from interleukin (IL)-17 inhibitors to IL-23 inhibitors remain limited. This study aimed to evaluate the clinical effectiveness, patient-reported outcomes, and dose selection associated with switching to tildrakizumab in patients with moderate-to-severe plaque psoriasis after failure of IL-17 inhibitor therapies. METHODS: In this prospective real-world study, 30 patients who failed a single IL-17 inhibitor were switched to tildrakizumab and followed for 52 weeks. Clinical outcomes (Psoriasis Area and Severity Index [PASI] and Physician Global Assessment [PGA]), response rates (75%, 90%, and 100% improvement in PASI score [PASI75, PASI90, and PASI100]), and patient-reported outcomes (Dermatology Life Quality Index [DLQI], World Health Organization-Five Well-Being Index [WHO-5], and nine-item Treatment Satisfaction Questionnaire for Medication [TSQM-9]) were assessed at baseline and weeks 4, 16, and 52. RESULTS: Rapid and sustained clinical improvement was observed, with mean PASI scores decreasing from 12.2 at baseline to 1.1 at week 52. At week 52, 88.9% of patients achieved PASI75, 66.7% PASI90, and 50% PASI100, while 94.4% reached PASI scores ≤ 3. Significant improvements were also observed in DLQI and WHO-5 scores, alongside high treatment satisfaction. Although 46.7% of patients initially received 100 mg, all were subsequently escalated to 200 mg, with no patients maintaining the lower dose throughout follow-up. CONCLUSIONS: Switching to tildrakizumab after anti-IL-17 failure resulted in significant clinical and patient-reported benefits over 52 weeks. Dose escalation from 100 to 200 mg was frequently observed during follow-up; however, the absence of a comparator group maintained on 100 mg precludes conclusions regarding the comparative effectiveness of the two dosing regimens.