Difamilast ointment in adult patients with atopic dermatitis: A phase 3 randomized, double-blind, vehicle-controlled trial

Difamilast is a selective phosphodiesterase 4 inhibitor. Phosphodiesterase 4 is involved in cytokine production linked with inflammatory disorders, including atopic dermatitis. To demonstrate the superiority of difamilast ointment 1% to vehicle in adult Japanese patients with atopic dermatitis. In this phase 3, randomized, double-blind trial, patients aged 15-70 years with an investigator global assessment score of 2 or 3 received topical difamilast ointment 1% (n = 182) or a vehicle (n = 182) twice daily for 4 weeks. The success rate in investigator global assessment score at week 4 (primary endpoint)—the percentage of patients achieving an investigator global assessment score of 0 or 1 with ≥2-grade improvement—was significantly higher with 1% difamilast than with the vehicle (38.46% vs 12.64%, respectively, P