A Study to Investigate the Efficacy and Safety of Lebrikizumab in Participants With Moderate-to-Severe Atopic Hand and Foot Dermatitis

Inclusion Criteria:

• Have an unequivocal diagnosis of chronic atopic hand and/or foot dermatitis at least 1 year prior to screening, regardless of the extent and severity of concomitantatopic dermatitis (AD) on other areas of the body. AD must be present in at least 2of the 4 mentioned anatomical areas: left hand, right hand, left foot, or right footat screening and baseline.

• Have a Hand Foot - Investigator Global Assessment (HF-IGA) score of 3 or 4 at thescreening and baseline visits.

• Have a baseline hand and foot peak pruritus (numeric rating scale) NRS score ≥4.

• Have a documented history by the investigator of inadequate response to topicalmedication(s) (topical corticosteroids (TCIs/TCS), topical PDE-4 inhibitors, ortopical janus kinase (JAK) inhibitors) in the treatment of atopic hand footdermatitis (AHFD) within 6 months of screening, or use of topical medications ismedically inadvisable (due to intolerance to treatment, hypersensitivity reactions,significant skin atrophy of hand and feet, and systemic effects, as assessed by theinvestigator or by the treating physician of the participant).

• For adolescent participants, body weight ≥40 kilograms (kg) at baseline.

Exclusion Criteria:

• Have a positive patch test reaction to 1 or more allergens (a score of 1+ or aboveaccording to the International Contact Dermatitis Research Group grading scale)before baseline AND which are deemed to be clinically relevant in the view of theinvestigator as the current cause of the hand and foot dermatitis.

• Have a documented diagnosis of allergic contact dermatitis (ACD) of hands and/orfeet, and have a positive patch test reaction at screening, regardless of whetherthe history of current skin exposure to products containing this allergen (currentrelevance) is present.

• Have a documented or strong clinical suspicion of the diagnosis of protein contactdermatitis of hands and/or feet. These are the participants with occupational ornonoccupational contact with proteins such as food, latex, and so on, who havepositive prick test results and present with lesions of contact urticaria ordermatitis on hands and feet.

• Have a documented exposure to irritants in the occupational or non-occupational (household/recreational) setting that is believed to be a predominant cause of thecurrent hand and foot dermatitis as per the judgment of the investigator.

• Presence of skin comorbidities on hand and/or foot that may interfere with studyassessments, such as (but not limited to) palmoplantar psoriasis, palmoplantarkeratoderma, impetiginized eczema, lichen planus, pityriasis rubra pilaris, herpessimplex, erythema multiforme, tinea, or scabies.

• Have skin comorbidities that may interfere with study assessments.

• Treatment with topical medications on the hands and feet within 2 weeks before thebaseline visit (except for the use of the participant's own emollients).

• Prior treatment with interleukin-13 (IL-13) inhibitors such as lebrikizumab ortralokinumab.

• Have received any live attenuated vaccine within less than 4 weeks of the baselinevisit or intend to receive a live attenuated vaccine during the study, or within 4weeks after receiving the last dose of study intervention.