A Study of Lebrikizumab (LY3650150) on Vaccine Response in Adults With Atopic Dermatitis (ADopt-VA)

Booster response to tetanus toxoid is defined as: ≥4-fold increase in anti-tetanus toxoid immunoglobulin G (IgG) antibody concentration if the pre-vaccination level was >0.10 International units per milliliter (IU/mL) and ≤2.7 IU/mL; OR ≥2-fold increase in anti-tetanus toxoid IgG antibody concentration if the pre-vaccination level was >2.7 IU/mL; OR ≥4-fold increase in anti-tetanus toxoid IgG antibody concentration and a post-vaccination level ≥0.10 IU/mL if the pre-vaccination level was ≤0.10 IU/mL

Positive antibody response to Meningococcus C antigen as measured by group C serum bactericidal antibodies is defined as: post-vaccination rabbit complement serum bactericidal assay (rSBA) titer ≥4 times the lower limit of quantitation (LLOQ), if the pre-vaccination rSBA titer is less than the LLOQ; OR post-vaccination rSBA titer ≥4 times the pre-vaccination titer, if the pre-vaccination rSBA titer is greater than or equal to the LLOQ.

The IGA measures the investigator's global assessment of the participants overall severity of their atopic dermatitis (AD), based on a static, numeric 5-point scale from 0 (clear skin) to 4 (severe disease). The score is based on an overall assessment of the degree of erythema, papulation/induration, oozing/crusting, and lichenification. Markov Chain Monte Carlo Multiple Imputation (MCMC-MI) was used to handle missing data.

The EASI-75 is defined as a ≥ 75% improvement from baseline in the EASI score. EASI assesses objective physician estimates of 2 dimensions of atopic dermatitis - disease extent and clinical signs, by scoring the extent of disease (percentage of skin affected: 0 = 0%; 1 = 1-9%; 2 = 10-29%; 3 = 30-49%; 4 = 50-69%; 5 = 70-89%; 6 = 90-100%) and the severity of 4 clinical signs (erythema, edema/papulation, excoriation, and lichenification) each on a scale of 0 to 3 (0 = none, absent; 1 = mild; 2 = moderate; 3 = severe) at 4 body sites (head and neck, trunk, upper limbs, and lower limbs). Half scores are allowed. The final EASI score will be obtained by weight-averaging these 4 scores and will range from 0 to 72. A higher score represents greater disease severity. MCMC-MI was used to handle missing data.

The EASI-90 is defined as a ≥ 90% improvement from baseline in the EASI score. EASI assesses objective physician estimates of 2 dimensions of atopic dermatitis - disease extent and clinical signs, by scoring the extent of disease (percentage of skin affected: 0 = 0%; 1 = 1-9%; 2 = 10-29%; 3 = 30-49%; 4 = 50-69%; 5 = 70-89%; 6 = 90-100%) and the severity of 4 clinical signs (erythema, edema/papulation, excoriation, and lichenification) each on a scale of 0 to 3 (0 = none, absent; 1 = mild; 2 = moderate; 3 = severe) at 4 body sites (head and neck, trunk, upper limbs, and lower limbs). Half scores are allowed. The final EASI score will be obtained by weight-averaging these 4 scores and will range from 0 to 72. A higher score represents greater disease severity. MCMC-MI was used to handle missing data.

The Pruritus NRS is an 11-point scale used by participants to rate their worst itch severity over the past 24 hours, with 0 indicating "No itch" and 10 indicating "Worst itch imaginable." MCMC-MI was used to handle missing data.

The BSA assessment estimates the extent of disease or skin involvement with respect to AD and is expressed as a percentage of body surface area. It was assessed for 4 body regions: head and neck, trunk (including genital region), upper extremities, and lower extremities (including the buttocks). Each body region will be assessed for disease extent ranging from 0% to 100%. BSA was calculated using the participant's palm, 1 palm = 1% with estimates of the number of palms it takes to cover the affected AD area. Maximum number of palms were 10 for head and neck (10%), 20 for upper extremities (20%), 30 for trunk, including axilla and groin (30%), and 40 for lower extremities, including buttocks (40%). Percent of BSA for a body region = total number of palms in a body region * % surface area equivalent to 1 palm. Overall percent BSA for an individual is arithmetic mean of % BSA of all 4 body regions and ranges from 0% to 100% with higher values representing greater severity of AD.

Sleep Loss due to interference of itch will be assessed by the participant. Participants rate their interference of itch on sleep based on a 5-point Likert scale [0 (not at all) to 4 (unable to sleep at all)]. Higher scores indicate a greater impact and worse outcome. Assessments will be recorded daily by the participant using an electronic diary, and the week 16 score was calculated by averaging the daily scores from the previous 7 days and the average score was used to compute a change from baseline. MCMC-MI was used to handle missing data.