A Study of Baricitinib (LY3009104) in Children From 6 Years to Less Than 18 Years of Age With Alopecia Areata

The main purpose of this study is to determine the efficacy and safety of Baricitinib for the treatment of severe or very severe alopecia areata (hair loss) in children from 6 years to less than 18 years of age.The study is divided into 4 periods, a 5-week Screening period, a 36-week Double-Blind Treatment Period, an approximately 2-year Long-term Extension Period, and a 4-week Post-treatment Follow-up period.

Inclusion Criteria:Have severe areata alopecia (AA) for at least 1 yearCurrent AA episode of at least 6 months' duration with hair loss encompassing ≥50% of the scalpSALT score ≥50% at screening and baselineHistory of trial and failure with at least 1 available treatment (topical or other) for AAHistory of psychological counseling related to AACurrent episode of severe AA of less than 8 years.Note: Participants who have severe AA for ≥8 years may be enrolled if episodes of regrowth, spontaneous or under treatment, have been observed on the affected areas over the past 8 years.Exclusion Criteria:Primarily "diffuse" type of AA (characterized by diffuse hair shedding).Are currently experiencing other forms of alopecia including, but not limited to: trichotillomania, telogen effluvium, chemotherapy-induced hair loss, or any other concomitant conditions (for example, tinea capitis, psoriasis, lupus erythematosus, or secondary syphilis) that would interfere with evaluations of the effect of study medication on AA.Are largely or wholly incapacitated permitting little or no self-care, such as being bedriddenHave uncontrolled arterial hypertensionHave had major surgery within 8 weeks prior to screening or will require major surgery during the studyHave a history or presence of cardiovascular, respiratory, hepatic, gastrointestinal, endocrine, hematological, neurological, or neuropsychiatric disorders or any other serious and/or unstable illness that, in the opinion of the investigator, could constitute an unacceptable risk when taking IP or interfere with the interpretation of data.Have a positive test for hepatitis B virus (HBV) infectionHave hepatitis C virus (HCV) infection (positive for anti hepatitis C antibody with confirmed presence of HCV ribonucleic acid [RNA]).Have evidence of human immunodeficiency virus (HIV) infection and/or positive HIV antibodies.