Efficacy of Deucravacitinib in Plaque Psoriasis Across a Range of Body Surface Area Involvement: Post hoc Analysis of the Randomized, Double-Blinded, Placebo-Controlled, Phase 3b/4 PSORIATYK SCALP Trial

Abstract

Introduction: Deucravacitinib, an oral, selective, allosteric tyrosine kinase 2 inhibitor, is approved in the US, EU, and other countries for treatment of adults with moderate to severe plaque psoriasis who are candidates for systemic therapy. Scalp involvement affects approximately 80% of patients with plaque psoriasis. PSORIATYK SCALP (NCT05478499) is an ongoing, 52-week, multicenter, phase 3b/4 trial evaluating deucravacitinib in patients with moderate to severe scalp psoriasis, including those with a range of total body surface area (BSA) involvement (≥3%). These patients are candidates for systemic therapy, according to the AAD/NPF and IPC treatment guidelines. This post hoc analysis assessed efficacy in overall body psoriasis.

Methods: Adults (age ≥18 years) with moderate to severe scalp psoriasis (scalp-specific Physician Global Assessment [PGA] ≥3, scalp surface area involvement ≥20%, and Psoriasis Scalp Severity Index ≥12 at baseline) and BSA involvement ≥3% were eligible for inclusion. Patients were randomized 1:2 to oral placebo (n=51) or deucravacitinib 6 mg once daily (n=103) through Week 16. Stratification factors included prior biologic use and body weight. Outcomes at Week 16 included static PGA score of 0 (clear) or 1 (almost clear) (sPGA 0/1), change from baseline in Psoriasis Area and Severity Index (PASI), and change from baseline in whole-body itch numeric rating scale (NRS). Nonresponder imputation (binary outcomes) and modified baseline observation carried forward (continuous outcomes) were used for patients with missing data. All P values are nominal.

Results: Baseline characteristics were similar between groups (deucravacitinib: mean [SD], BSA 10.5% [9.6%], PASI 10.2 [6.7], whole-body itch NRS 5.8 [2.8]; placebo: mean [SD], BSA 10.0% [8.1%], PASI 9.4 [5.6], whole-body itch NRS 5.8 [2.4]). Baseline total BSA involvement was 3%-10% in most patients (deucravacitinib, 68.0%; placebo, 74.5%). At Week 16, a significantly higher proportion of patients receiving deucravacitinib versus placebo achieved sPGA 0/1 (47.6% [95% CI, 37.6%-57.6%] vs 3.9% [0.5%-13.5%], respectively; P<0.0001). Similarly, patients treated with deucravacitinib achieved greater decreases in adjusted mean change from baseline in PASI (−6.4 [95% CI, −7.3 to −5.5] vs −1.3 [−2.6 to −0.1]; P<0.0001) and whole-body itch NRS (−2.9 [−3.4 to −2.4] vs −0.4 [−1.1 to 0.3]; P<0.0001).

Conclusion: In the phase 3b/4 PSORIATYK SCALP trial, deucravacitinib was efficacious in improving overall psoriasis. Efficacy was consistent with the results observed in the phase 3 POETYK PSO-1/PSO-2 trials, despite including patients with less extensive total BSA involvement.