A Study of ARRY-371797 in Patients With Rheumatoid Arthritis

Key Inclusion Criteria:

• Diagnosed with rheumatoid arthritis (RA) at least 3 months prior to study start based upon the American College of Rheumatology (ACR) 1987 Revised Criteria.
• On a stable weekly dose of both methotrexate (MTX) (10 - 25 mg/week inclusively; either oral or parenteral) and folate (≥ 5 mg weekly ) for ≥ 6 weeks prior to study start and is willing to continue on these regimens for the duration of the study.
• Meets the ACR 1991 Revised Criteria for Global Functional Status in RA, Class I, II, or III.
• Completed an appropriate washout period if treated with specified therapies.
• Patients may continue on specified stable background therapy for RA (doses should be stable for at least 6 weeks prior to the first dose of study drug, unless the patient stops due to documented disease improvement, with Sponsor approval).
• Additional criteria exist.

Key Exclusion Criteria:

• Diagnosis of any other inflammatory or non-inflammatory arthritis (e.g. spondyloarthritis; fibromyalgia, psoriatic arthritis, crystal-proven gout) that may interfere with disease activity assessments and/or clinically apparent osteoarthritis which would affect subsequent efficacy measures.
• Has received any of the following prior treatments:

• Within 4 weeks of first dose of study drug: anakinra (Kineret®), etanercept (Enbrel®);
• Within 8 weeks of first dose of study drug: infliximab (Remicade®), adalimumab (Humira®), leflunomide (Arava®);
• At any time: rituximab (Rituxan®), alemtuzumab (CamPath®), any experimental B cell targeting agents.
• Treatment with potent CYP3A inhibitors or inducers, disease-modifying antirheumatic drugs (DMARDs) and/or biologic response modifiers (BRMs) during the study.
• Additional criteria exist.