Safety and Efficacy of Abatacept Versus Placebo in Participants With Psoriatic Arthritis

A Phase IIB, Multi-Dose, Multi-center, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of Abatacept Versus Placebo in the Treatment of Psoriatic Arthritis

The purpose of this study is to determine an optimal abatacept dosing regimen for the treatment of active arthritis due to psoriatic arthritis in patients who have had a prior inadequate response to disease-modifying antirheumatic drugs, including methotrexate and tumor necrosis factor alpha-blockade compounds.

Key Inclusion Criteria:

• Meeting classification criteria for psoriatic arthritis for a duration of disease of at least 3 months
• Prior failure (inefficacy or intolerance) of therapy with disease-modifying antirheumatic drugs; if patient had prior failure of methotrexate, he or she must have been taking at least 15 mg per week for at least 2 months
• If recent failure(inefficacy or intolerance) of a tumor necrosis factor α-blockade compound, participant must be washed out prior to first dose: 56 days for infliximab and 28 days for etanercept and adalimumab
• Disease activity as defined by a tender joint count of ≥3, swollen joint count of ≥3, and clinically detectable synovitis at screening and Day 01 (prior to infusion)
• Active psoriasis with a qualifying target lesion ≥2 cm in diameter
• Able to undergo magnetic resonance imaging
• Use of appropriate birth control by women of child bearing potential (WOCBP)

Key Exclusion Criteria:

• WOCBP who are unwilling or unable to use an acceptable method to avoid pregnancy for the entire study period and for up to 10 weeks after the last dose of investigational product
• Women who are pregnant or breastfeeding or who plan to become pregnant or to start breastfeeding during the duration of the study
• Women with a positive pregnancy test on enrollment or prior to investigational product administration.
• Participants scheduled for or anticipating joint replacement surgery.
• Those with a recent history of clinically significant drug or alcohol abuse
• Concomitant illness that in the investigator's opinion is likely to require systemic glucocorticosteroid therapy during the study (for example: moderate to severe asthma)
• Current symptoms of severe, progressive, or uncontrolled renal, hepatic, hematologic, pulmonary, cardiac, neurologic, ophthalmologic, or cerebral disease.
• Unwillingness or inability to undergo screening based on current local or country guidelines/standards to evaluate the presence of cancer
• Cancer within the last 5 years
• Current malignancy or signs of possible malignancy detected by screening procedures for which the workup to exclude malignancy has not been completed or malignancy cannot be excluded
• At risk for or history (within 3 years) of tuberculosis
• Any serious bacterial infection within the last 3 months, not treated and resolved with antibiotics, or any chronic bacterial infection (such as, but not limited to, chronic pyelonephritis, osteomyelitis, and bronchiectasis)
• Evidence of active or latent bacterial or viral infection infections at the time of potential enrollment
• Herpes zoster or cytomegalovirus resolving less than 2 months prior to signing informed consent
• Receipt of any live vaccines within 3 months of the anticipated first dose of study medication or anticipation of the need for a live vaccine at any time during and for 3 months after the duration of the study

Long-term period participants: Must have met eligibility criteria for short-term period and completed short-term (24-week) period of the study