• The primary outcomes are American College of Rheumatology (ACR) 20 response at Week 14, and change from baseline in the Health Assessment Questionnaire (HAQ) at Week 24. [ Time Frame: Week 14 and Week 24 ] [ Designated as safety issue: No ]
  

• The secondary outcomes are change from baseline in van der Heijde-Sharp (vdH-S) score at Week24, Disease Activity Score (DAS) 28 response (using C-reactive protein) at Week14, ACR20 response at Week 24, change from baseline in HAQ at Week14. [ Time Frame: Week 14 and Week 24 ] [ Designated as safety issue: No ]
  

Golimumab is a fully human protein (antibody) which binds to tumor necrosis factor (TNFα). TNFα is increased in patients with rheumatoid arthritis (RA), and plays a major role in causing the joint pain, swelling, and damage from RA. Other marketed drugs that target TNFα (anti-TNFα drugs) have been shown to be effective in reducing the symptoms, signs, and joint damage of RA, but have limitations with respect to safety and ease of use. This is a randomized, double-blind, placebo-controlled trial of the efficacy and safety of a new anti-TNFα drug, golimumab, at 2 doses, injected under the skin every 4 weeks, alone or in combination with methotrexate, compared with methotrexate alone, in subjects with active RA despite treatment with methotrexate. The study hypothesis is that golimumab, alone or in combination with methotrexate, will be more effective in treatment of RA than methotrexate alone, as measured by the American College of Rheumatology (ACR) response criteria and change from baseline in the Health Assessment Questionnaire (HAQ), without causing unacceptable significant adverse effects. The ACR response criteria were designed to determine the percentage of subjects who have achieved a certain level of improvement in their signs and symptoms of RA. The HAQ is a series of questions that measure a subject's impairment in physical function caused by RA. Other secondary measures of effectiveness include the van der Heijde Modified Sharp (vdH-S) score, which is a measurement of the amount of joint damage in a subject as seen by x-ray.

Golimumab 50 mg or 100 mg or placebo injections under the skin every 4 weeks through week 20. Methotrexate or placebo capsules will be given in addition. At Week 24, all subjects receive golimumab 50mg or 100mg injections, and golimumab continues for all groups for about 4 and a half more years.