A Study of Long-term Baricitinib (LY3009104) Therapy in Atopic Dermatitis

Have participated in previous studies (JAHL, JAHM and JAIY) and met specific completion requirements for those studies, and do not meet any of the following Exclusions:

Exclusion Criteria:

• Had investigational product permanently discontinued at any time during a previousBaricitinib study.

• Had temporary investigational product interruption continue at the final study visitof a previous Baricitinib study and, in the opinion of the investigator, this posesan unacceptable risk for the participant's participation in the study

OR

Have not participated in previous studies (JAHL, JAHM and JAIY) and satisfy the following criteria:

Inclusion Criteria:

• Have been diagnosed with moderate to severe Atopic Dermatitis for at least 12months.

• Have had inadequate response or intolerance to existing topical (applied to theskin) medications within 6 months preceding screening.

• Are willing to discontinue certain treatments for eczema (such as systemic andtopical treatments during a washout period).

• Agree to use emollients daily.

Exclusion Criteria:

• Are currently experiencing or have a history of other concomitant skin conditions (e.g., psoriasis or lupus erythematosus), or a history of erythrodermic, refractory,or unstable skin disease that requires frequent hospitalizations and/or intravenoustreatment for skin infections.

• A history of eczema herpeticum within 12 months, and/or a history of 2 or moreepisode of eczema herpeticum in the past.

• Participants who are currently experiencing a skin infection that requirestreatment, or is currently being treated, with topical or systemic antibiotics.

• Have any serious illness that is anticipated to require the use of systemiccorticosteroids or otherwise interfere with study participation or require activefrequent monitoring (e.g., unstable chronic asthma).

• Have been treated with the following therapies:

• Monoclonal antibody for less than 5 half-lives prior to randomization.

• Received prior treatment with any oral Janus kinase (JAK) inhibitor.

• Received any parenteral corticosteroids administered by intramuscular orintravenous (IV) injection within 2 weeks prior to study entry or within 6weeks prior to planned randomization or are anticipated to require parenteralinjection of corticosteroids during the study.

• Have had an intra-articular corticosteroid injection within 2 weeks prior tostudy entry or within 6 weeks prior to planned randomization.

• Have high blood pressure characterized by a repeated systolic blood pressure >160millimeters of mercury (mm Hg) or diastolic blood pressure >100 mm Hg.

• Have had major surgery within the past eight weeks or are planning major surgeryduring the study.

• Have experienced any of the following within 12 weeks of screening: venousthromboembolic event (VTE), myocardial infarction (MI), unstable ischemic heartdisease, stroke, or New York Heart Association Stage III/IV heart failure.

• Have a history of recurrent (≥ 2) VTE or are considered at high risk of VTE asdeemed by the investigator.

• Have a history or presence of cardiovascular, respiratory, hepatic, chronic liverdisease gastrointestinal, endocrine, hematological, neurological,lymphoproliferative disease or neuropsychiatric disorders or any other seriousand/or unstable illness.

• Have a current or recent clinically serious viral, bacterial, fungal, or parasiticinfection including herpes zoster, tuberculosis.

• Have specific laboratory abnormalities.

• Have received certain treatments that are contraindicated.

• Pregnant or breastfeeding.