Powdered infant formula grade lactose will be provided to infants once daily for 12 weeks.

Time to onset of AD through Weeks 52 and 104 will be reported.

Percentage of infants with B. infantis gut colonization at Week 12 will be reported.

Percentage of participants with at least mild Atopic Dermatitis (AD) severity based on the EASI score at Weeks 12, 52, and 104 will be reported. Physician rates severity of four parameters: erythema, infiltration, excoriation and lichenification on a scale of 0 (none) to 3 (severe) on 4 anatomic regions of the body: head, trunk, upper limbs, and lower limbs. Physician determines how much area is affected on a scale of 0 (none) to 6 (90 to 100%). A body region score is determined by multiplying the sum of the severity scores by the affected area score by a constant corresponding to the relative body surface area for that body region (20%, 30%, 20%, and 30%, respectively). The 4 body region scores are summed to yield the EASI score which ranges from 0 to 72, with a higher score indicating more severe AD. The AD onset in the study's population can be diagnosed throughout the study at either scheduled or unscheduled visits starting as early as 1 month of age.

Time to onset of at least mild Atopic Dermatitis (AD) severity based on the EASI score up to Week 104 will be reported. Physician rates severity of four parameters: erythema, infiltration, excoriation and lichenification on a scale of 0 (none) to 3 (severe) on 4 anatomic regions of the body: head, trunk, upper limbs, and lower limbs. Physician determines how much area is affected on a scale of 0 (none) to 6 (90 to 100%). A body region score is determined by multiplying the sum of the severity scores by the affected area score by a constant corresponding to the relative body surface area for that body region (20%, 30%, 20%, and 30%, respectively). The 4 body region scores are summed to yield the EASI score which ranges from 0 to 72, with a higher score indicating more severe AD. The AD onset in the study's population can be diagnosed throughout the study at either scheduled or unscheduled visits starting as early as 1 month of age.

The POEM is a simple, valid, easily interpreted, and reproducible tool for assessing AD and monitoring aspects of the disease that are important to participants with AD. Study Personnel will interview Caregivers at time of AD diagnosis and (only for participants with AD) at Weeks 12, 52, and 104 to rate seven symptoms (itchy skin, sleep disturbance, bleeding skin, skin weeping/oozing, skin flaking, skin cracking, skin dryness/roughness) using a 5-point scale of frequency of occurrence during the previous week (no days, 1-2 days, 3-4 days, 5-6 days, every day). The total score is the sum of the 7 items which is ranged from 0 to 28; a high score is indicative of more severe AD. The AD onset in the study's population can be diagnosed throughout the study at either scheduled or unscheduled visits starting as early as 1 month of age.

The POEM is a simple, valid, easily interpreted, and reproducible tool for assessing AD and monitoring aspects of the disease that are important to participants with AD. Study Personnel will interview Caregivers at time of AD diagnosis and (only for participants with AD) at Weeks 12, 52, and 104 to rate seven symptoms (itchy skin, sleep disturbance, bleeding skin, skin weeping/oozing, skin flaking, skin cracking, skin dryness/roughness) using a 5-point scale of frequency of occurrence during the previous week (no days, 1-2 days, 3-4 days, 5-6 days, every day). The total score is the sum of the 7 items which is ranged from 0 to 28; a high score is indicative of more severe AD. The AD onset in the study's population can be diagnosed throughout the study at either scheduled or unscheduled visits starting as early as 1 month of age.