Abstract
INTRODUCTION: Psoriasis (PsO) in the genital and scalp areas is associated with increased patient burden and impact on quality of life. Effective treatments for PsO in these high-impact areas are essential, though patients are frequently excluded from both biologic clinical trials and treatment because of their often low overall affected body surface area (BSA) despite the disproportionate impact of PsO on their quality of life. Recent guidance also considers these patients as candidates for advanced therapies. Here, we compare the efficacy and safety of risankizumab, an interleukin-23 inhibitor approved for the treatment of moderate-to-severe plaque psoriasis, versus placebo in the treatment of PsO in the genital or scalp region. METHODS: UnlIMMited (NCT05969223) is an ongoing phase 4, multicenter, randomized, double-blind, placebo-controlled study for adult patients with moderate-to-severe genital or scalp PsO in patients with < 10% BSA or ≥ 10% BSA involvement. Two parallel studies were conducted with study-G assessing genital PsO and study-S assessing scalp PsO. Patients were randomized 1:1 within each study to receive either 150 mg risankizumab or placebo at weeks 0 and 4. The primary endpoints for the studies were the achievement of static Physician's Global Assessment - Genital (sPGA-G) 0/1 for study-G and scalp Investigator Global Assessment (IGA) 0/1 for study-S, both assessed at week 16. Secondary endpoints are also reported at week 16 in each study assessing skin clearance, symptom resolution, and impact on quality of life. Safety was reported through the first 16 weeks. RESULTS: At week 16, in both studies, a significantly higher proportion of patients receiving risankizumab achieved the primary endpoints compared with placebo. In study-G, 69.1% of patients receiving risankizumab versus 13.0% of patients receiving placebo achieved sPGA-G 0/1 (P < 0.0001). In study-S, 60.8% of patients receiving risankizumab versus 13.0% of patients receiving placebo achieved scalp IGA 0/1 (P < 0.0001). No new safety signals were identified. CONCLUSION: These results demonstrate that risankizumab is effective in the treatment of genital and scalp psoriasis at week 16, with no new safety signals identified. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov identifier NCT05969223.