Phase 1 Study of CC-90005 in Healthy Subjects and Subjects With Moderate to Severe Plaque-type Psoriasis

This is a 2-part study to be conducted at multiple study centers. Part 1 is a randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, and pharmacokinetics of CC-90005 following a single oral dose in healthy subjects. During the course of Part 1, each subject will participate in a screening phase, baseline phase(s), treatment phase(s) and a follow up visit. There will be a total of 3 planned cohorts, each of which will consist of a different dose level, with 8 subjects per cohort. In each cohort, 6 subjects will receive a dose of CC 90005 and 2 subjects will receive placebo depending on the randomization schedule. Each cohort will receive a minimum of 2 doses, with one of the cohorts receiving a third dose (up to three study periods per cohort). Administration of study drug at the next higher dose level will not begin until the safety and tolerability of the preceding dose have been evaluated and deemed acceptable by the investigator and sponsor's medical monitor. Part 2 is a randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, and pharmacokinetics of CC-90005 following multiple oral doses in subjects with moderate to severe plaque-type psoriasis. During the course of Part 2, each subject will participate in a screening phase, a baseline phase, a treatment phase and a follow up visit. There will be a total of 4 planned cohorts, each of which will consist of a different dose level, with 12 subjects per cohort. In each cohort, 9 subjects will receive a dose of CC-90005 and 3 subjects will receive placebo depending on the randomization schedule. It is planned for study drug to be administered twice daily for 28 days. Proposed dose levels in Part 2 may be modified and/or eliminated based on data obtained from Part 1 and/or from previous data obtained in Part 2.