An Effectiveness and Safety Study of CNTO 1275 in Patients With Active Psoriatic Arthritis

Inclusion Criteria: * Have had active psoriatic arthritis for at least 6 months prior to administration of first study injection * Have an active plaque psoriasis (defined as a lesion of at least 2 cm in diameter), but not in armpits, on chest between breasts or groin * Women of childbearing potential and all men must be using an effective method of birth control measures (eg, abstinence, oral contraceptives, intrauterine device, barrier method with spermicide, or surgical sterilization) and must agree to continue to use such measures until 12 months after receiving the last injection of study agent * Have an active arthritis despite disease-modifying anti-rheumatic drugs (DMARD) such as leflunomide, gold, sulfasalazine, but not including methotrexate) or non-steroidal anti-inflammatory agents (NSAID) such as aspirin, ibuprofen, naproxen) therapy. DMARD therapy is defined as taking a DMARD for at least 3 months, or evidence of not tolerating DMARD. NSAID therapy is defined as taking an NSAID for at least 4 weeks * If the patients are using methotrexate (MTX), they should have started treatment at least 3 months prior to the first administration of study agent and should have no serious toxic side effects attributable to MTX * Have no signs or symptoms suggestive of active tuberculosis upon medical history, physical examination and chest X-ray Exclusion Criteria: * Have received DMARDs, other than methotrexate, within 4 weeks prior to the randomization visit * Have used any biologic within the previous 3 months or 5 times the half-life of the biologic, whichever is longer * Have received any oral, intravenous or intramuscular medications/treatments that could affect psoriasis (including, but not limited to, oral or injectable corticosteroids, retinoids, 1,25 dihydroxy vitamin D3 and analogues, psoralens, sulfasalazine, hydroxyurea, fumaric acid derivatives, or phototherapy) within 4 weeks of the randomization visit and/or have used topical medications/treatments that could affect psoriasis (eg, corticosteroids, anthralin, calcipotriene, topical vitamin D derivatives, retinoids, tazarotene, methoxsalen, trimethylpsoralens) within 2 weeks of the randomization visit * Have a history of chronic or recurrent infectious disease, including but not limited to chronic renal infection, chronic chest infection (eg, bronchiectasis), recurrent urinary tract infection (recurrent pyelonephritis or chronic nonremitting cystitis), or open, draining, or infected skin wounds or ulcers * Have a history of latent or active granulomatous infection, including tuberculosis (TB), histoplasmosis, or coccidioidomycosis, prior to screening * Have current signs or symptoms of severe, progressive, or uncontrolled kidney, liver, blood, intestinal, hormonal, lung, heart, nervous, brain, or psychiatric disease * Have any known cancer or have a history of cancer within the previous 5 years (with the following exception: have had basal cell carcinoma or squamous cell carcinoma in situ of the skin that has been treated, with no evidence of recurrence)