Efficacy and safety of crisaborole ointment, a novel, nonsteroidal phosphodiesterase 4 (PDE4) inhibitor for the topical treatment of atopic dermatitis (AD) in children and adults

Background Additional topical treatments for atopic dermatitis (AD) are needed that provide relief while minimizing risks. Objective We sought to assess the efficacy and safety of crisaborole ointment, a phosphodiesterase 4 inhibitor, in two phase III AD studies (AD-301: NCT02118766; AD-302: NCT02118792). Methods Two identically designed, vehicle-controlled, double-blind studies enrolled and randomly assigned (2:1, crisaborole:vehicle) patients aged 2 years or older with an Investigator's Static Global Assessment (ISGA) score of mild or moderate for twice-daily application for 28 days. The primary end point was ISGA score at day 29 of clear (0)/almost clear (1) with 2-grade or greater improvement from baseline. Additional analyses included time to success in ISGA score, percentage of patients achieving clear/almost clear, reduction in severity of AD signs, and time to improvement in pruritus. Results More crisaborole- than vehicle-treated patients achieved ISGA score success (clear/almost clear with ≥2-grade improvement; AD-301: 32.8% vs 25.4%, P = .038; AD-302: 31.4% vs 18.0%, P < .001), with a greater percentage with clear/almost clear (51.7% vs 40.6%, P = .005; 48.5% vs 29.7%, P < .001). Crisaborole-treated patients achieved success in ISGA score and improvement in pruritus earlier than those treated with vehicle (both P ≤ .001). Treatment-related adverse events were infrequent and mild to moderate in severity. Limitations Short study duration was a limitation. Conclusions Crisaborole demonstrated a favorable safety profile and improvement in all measures of efficacy, including overall disease severity, pruritus, and other signs of AD.