Study of the Safety and Efficacy of Adalimumab in Subjects With Moderate to Severe Chronic Plaque Psoriasis

Inclusion Criteria: * Subject completed prior PS study Exclusion Criteria: * Subject has other active skin diseases * Multiple concomitant therapy restrictions and/or washouts (topicals, UV, other systemic PS therapies) * Poorly controlled medical conditions * History of neurologic symptoms suggestive of central nervous system (CNS) demyelinating disease * History of cancer or lymphoproliferative disease * History of active TB or listeriosis, or persistent chronic or active infections * Known to have immune deficiency or is immunocompromised * Clinically significant abnormal laboratory test results * Erythrodermic psoriasis or generalized pustular psoriasis