Crisaborole ointment, 2%, is a nonsteroidal phosphodiesterase 4 inhibitor for the treatment of mild-to-moderate atopic dermatitis. This post hoc analysis pools results from 2 phase 3 studies (ClinicalTrials.gov, NCT02118766 [AD-301]; NCT02118792 [AD-302]) to evaluate crisaborole efficacy in patients ≥ 2 years with mild-to-moderate atopic dermatitis (per Investigator's Static Global Assessment) using the Atopic Dermatitis Severity Index (ADSI) and percentage of treatable body surface area (%BSA). Patients were randomly assigned 2:1 to receive crisaborole (n = 1,016) or vehicle (n = 506) twice daily for 28 days. ADSI scores were the sum of pruritus, erythema, exudation, excoriation, and lichenification severity scores, each graded on a 4-point scale from none (0) to severe (3). Respective mean changes in ADSI score and %BSA at day 29 were (crisaborole vs. vehicle) -3.52 versus -2.42 (p < 0.0001) and -7.43 versus -4.44 (p < 0.0001). Crisaborole was effective in treating mild-to-moderate atopic dermatitis based on ADSI and %BSA.