Efficacy and safety of apremilast in patients with moderate-to-severe genital psoriasis: Results from DISCREET, a phase 3 randomized, double-blind, placebo-controlled trial

Background: Genital psoriasis can be stigmatizing, is highly prevalent among patients with psoriasis, and has limited treatment options. Apremilast is a unique oral immunomodulating phosphodiesterase 4 inhibitor approved for psoriasis treatment. Objective: To assess the efficacy and safety of apremilast 30 mg twice daily in patients with genital psoriasis. Methods: DISCREET, a phase 3, placebo-controlled trial (NCT03777436), randomized patients with moderate-to-severe genital psoriasis (stratified by affected body surface area <10% or ≥10%) to apremilast or placebo for a 16-week period, followed by an apremilast extension period. Week 16 results are presented. Results: Patients were randomized to apremilast (n = 143) or placebo (n = 146). At Week 16, 39.6% and 19.5% of apremilast and placebo patients, respectively, achieved a modified static Physician Global Assessment of Genitalia response (primary endpoint; score of 0/1, ≥2-point reduction); treatment difference was significant (20.1%, P = .0003). Improvements in genital signs and symptoms, skin involvement, and quality of life were observed. Common treatment-emergent adverse events were diarrhea, headache, nausea, and nasopharyngitis. Limitations: Lack of active-comparator. Conclusions: Apremilast demonstrated statistically and clinically meaningful genital Physician Global Assessment responses and improvement of signs, symptoms, severity, and quality of life in this first randomized, controlled study of an oral systemic treatment in patients with genital psoriasis.