An Efficacy and Safety Study of JNJ-26113100 in the Treatment of Adult Atopic Dermatitis

This study is a double-blind (neither the researchers nor the participants know what treatment the participant is receiving), randomized (study drug assigned by chance), placebo-controlled (an inactive substance; a pretend treatment \[with no drug in it\] that is compared in a clinical trial with a drug to test if the drug has a real effect), sequential cohort exploratory study to evaluate the safety and effectiveness of JNJ-26113100 in the treatment of adult AD that is moderate in severity, including its effect on inflammatory biomarkers (biological molecule found in blood, other body fluids, or tissues that is a sign of a normal or abnormal process, or of a condition or disease). Participants will be sequentially assigned to 50 milligram (mg) once daily, 100 mg once daily, 100 mg twice daily or 250 mg twice daily cohort and randomly assigned to receive JNJ-26113100 or matching placebo. The total duration of the study will be approximately 8 weeks. Participants will be asked to follow-up at the end of Week 1, 2, 3, 4, 5 and 6. A study termination visit (Day 57) will be conducted at the end of Week 8. Skin biopsies from atopic dermatitis lesions will be collected during the study to assess changes in the inflammatory disease state. Participants developing flares of their disease may be treated with triamcinolone acetonide 0.1 percent ointment twice daily for up to 7 days. Efficacy will be assessed using Investigator's Global Assessment (IGA), Eczema Area and Severity Index (EASI) and Visual Analog Scale (VAS). Blood and urine samples will be collected for standard safety laboratory tests, to measure the level of drug and effect of the drug on inflammatory biomarkers. Participant's safety will be monitored throughout the study.