In a randomized phase 2b trial (NCT03703102) for adult patients with moderate-to-severe atopic dermatitis (AD), treatment with the T cell rebalancing anti-OX40 receptor antibody rocatinlimab (AMG 451/KHK4083) led to significant improvements in clinical measurements versus placebo including whole-body Eczema Area and Severity Index (EASI) score. AD manifestations can impact variable anatomic regions, and involvement of the head and neck, a sensitive, hard-to-treat area, can negatively impact quality of life. In this post hoc analysis, we investigated response to rocatinlimab treatment across anatomic regions, including the head and neck. Least squares mean change from baseline to Week 56 in EASI score was analyzed by anatomic region (head and neck, trunk, upper extremities, or lower extremities) for patients with baseline moderate-to-severe AD in the respective anatomic region, using mixed models for repeated measures. Rocatinlimab groups were compared with placebo at Week 16. The proportion of patients achieving at least 75% reduction from baseline in EASI (EASI-75) was calculated. Probability of relapsing in EASI-75 during the off-treatment follow-up period (Weeks 36-56) was estimated using a Kaplan - Meier approach. At Week 16, decrease from baseline in mean EASI score was greater with all rocatinlimab regimens versus placebo across all anatomic regions for patients with baseline moderate-to-severe AD in the respective region (all P < 0.001). EASI scores continued to improve on treatment after Week 16 and were maintained during the off-treatment period across all regions. Among patients with baseline moderate-to-severe AD in the head and neck (n = 219; rocatinlimab, n = 174; placebo, n = 45), mean difference (rocatinlimab vs placebo) at Week 16 in LS mean percent change in head and neck EASI score ranged from - 30.4% to - 42.6% across treatment regimens. In patients who received rocatinlimab from the start of the trial, 47% - 71% achieved EASI-75 in the head and neck at Week 36. Among EASI-75 responders at Week 36, the probability of relapsing in EASI-75 in any region was low (< 25% in the head and neck) 20weeks after treatment discontinuation until Week 56.Rocatinlimab treatment led to durable improvements in AD across multiple anatomic regions, including the sensitive head and neck region.