Efficacy, Safety, and Tolerability Study of Apremilast to Treat Early Oligoarticular Psoriatic Arthritis.

This clinical study will test the effects of a drug called apremilast in oligoarticular psoriatic arthritis with less than 5 years of disease duration. In previous studies, apremilast has been shown to be safe and efficacious in reducing signs and symptoms of psoriatic arthritis, as well as improving physical function. This study will compare the effects of apremilast to placebo on psoriatic arthritis subjects in which the number of affected joints is limited (greater than 1 but less or equal to 4). About 285 patients worldwide will take part in this study.

Inclusion Criteria: * ≥ 18 yrs, male or female subject * Subjects must have signs and symptoms of PsA ≤5 years duration at the time of the Screening Visit * SJC AND TJC must be \>1 and ≤ 4 * For all regions, the local Regulatory Label for treatment with apremilast must be followed. * Stable doses of protocol-allowed PsA medications * General good health (except for psoriatic arthritis) as judged by the Investigator, based on medical history, physical examination, and clinical laboratories. (Note: The definition of good health means a subject does not have uncontrolled significant comorbid conditions). * Comply with protocol-required contraception measures * Subject meets the Classification Criteria for Psoriatic Arthritis \[CASPAR\] Criteria for PsA at the Screening visit Exclusion Criteria: * Prior use of \>2 csDMARD to treat PsA * Prior exposure to a JAK-inhibitor and/or a biologic DMARD. * Use of intra-articular (IA) or intra-muscular (IM) glucocorticoid injection within 8 weeks before the Baseline Visit. * Use of leflunomide within 12 weeks of randomization. Subjects who stopped leflunomide and completed 11 days of treatment with cholestyramine (8 g, 3 x daily) prior to the Baseline Visit may enter the study. * Prior use of cyclosporine. * Prior treatment with apremilast, or participation in a clinical study, involving apremilast. * Use of any investigational drug within 4 weeks of the Baseline Visit, or 5 pharmacokinetic/pharmacodynamic half-lives, if known (whichever is longer).