Moderate to severe atopic dermatitis (
AD
) has a high disease burden and a significant effect on quality of life. Observational studies are necessary to determine the patient disease burden and long‐term disease control in the Japanese population.
ADDRESS
‐J is a non‐interventional, observational registry of adult Japanese patients with moderate to severe
AD
. Herein, we report baseline data from the
ADDRESS
‐J study describing disease characteristics and current treatment practices. At baseline, 300 adult
AD
patients with Investigator's Global Assessment (
IGA
) scores (range, 0–4) of 3 (moderate) or 4 (severe) whose treatments for
AD
were intensified, were assessed for clinical and patient‐reported outcomes and current
AD
treatments. The registry patients’ median age was 34.0 years; 60.7% were male and 71.7% had had
AD
for more than 20 years. At baseline, 220 study patients had an
IGA
score of 3 and 80 had an
IGA
score of 4. The median Eczema Area and Severity Index score was 21.7 (range, 0–72), the median body surface area involvement was 46.25%, and the median pruritus numerical rating scale score was 7.0 (range, 0–10); for each of these measures, higher scores represent greater severity. Most registry patients (86.7%) had recently used topical corticosteroids or topical calcineurin inhibitors as treatment for
AD
. This registry cohort represents a population of Japanese patients with moderate to severe
AD
and provides an important resource for characterizing the disease burden and evaluating the safety and effectiveness of various
AD
treatments.