Effect of Roflumilast Cream vs Vehicle Cream on Chronic Plaque Psoriasis: The DERMIS-1 and DERMIS-2 Randomized Clinical Trials

IMPORTANCE: Once-daily roflumilast cream, 0.3%, a potent phosphodiesterase 4 inhibitor, demonstrated efficacy and was well tolerated in a phase 2b trial of patients with psoriasis. OBJECTIVE: To evaluate the efficacy of roflumilast cream, 0.3%, applied once daily for 8 weeks in 2 trials of patients with plaque psoriasis. DESIGN, SETTING, AND PARTICIPANTS: Two phase 3, randomized, double-blind, controlled, multicenter trials (DERMIS-1 [trial 1; n = 439] and DERMIS-2 [trial 2; n = 442]) were conducted at 40 centers (trial 1) and 39 centers (trial 2) in the US and Canada between December 9, 2019, and November 16, 2020, and between December 9, 2019, and November 23, 2020, respectively. Patients aged 2 years or older with plaque psoriasis involving 2% to 20% of body surface area were enrolled. The dates of final follow-up were November 20, 2020, and November 23, 2020, for trial 1 and trial 2, respectively. INTERVENTIONS: Patients were randomized 2:1 to receive roflumilast cream, 0.3% (trial 1: n = 286; trial 2: n = 290), or vehicle cream (trial 1: n = 153; trial 2: n = 152) once daily for 8 weeks. MAIN OUTCOMES AND MEASURES: The primary efficacy end point was Investigator Global Assessment (IGA) success (clear or almost clear status plus ≥2-grade improvement from baseline [score range, 0-4]) at week 8, analyzed using a Cochran-Mantel-Haenszel test stratified by site, baseline IGA score, and intertriginous involvement. There were 9 secondary outcomes, including intertriginous IGA success, 75% reduction in Psoriasis Area and Severity Index (PASI) score, and Worst Itch Numeric Rating Scale score of 4 or higher at baseline achieving 4-point reduction (WI-NRS success) at week 8 (scale: 0 [no itch] to 10 [worst imaginable itch]; minimum clinically important difference, 4 points). RESULTS: Among 881 participants (mean age, 47.5 years; 320 [36.3%] female), mean IGA scores in trial 1 were 2.9 [SD, 0.52] for roflumilast and 2.9 [SD, 0.45] for vehicle and in trial 2 were 2.9 [SD, 0.48] for roflumilast and 2.9 [SD, 0.47]) for vehicle. Statistically significantly greater percentages of roflumilast-treated patients than vehicle-treated patients had IGA success at week 8 (trial 1: 42.4% vs 6.1%; difference, 39.6% [95% CI, 32.3%-46.9%]; trial 2: 37.5% vs 6.9%; difference, 28.9% [95% CI, 20.8%-36.9%]; P