Participants received double-blind adalimumab 40 mg administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible at Week 12 or after) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible at Week 12 or after) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Double-blind adalimumab-matching placebo administered subcutaneously (SC)every other week (eow)

Open-label adalimumab 40 mg administered subcutaneously (SC) every other week (eow) after completion of the first 26 weeks in the study

Open-label adalimumab 40 mg administered subcutaneously (SC) every other week (eow) as rescue treatment to complete the first 26 weeks in the study- dependent on participant eligibility (increase in disease activity), applies to Weeks 12 to 26

Patients were ACR50 responders if they had: >= 50% improvement in both tender joint count (68 joints) and in swollen joint count (66 joints) plus >=50% improvement in at least 3 of the 5 remaining ACR core measures: patient's assessment of pain; patient's global assessment of disease activity; physician's global assessment of disease activity; self-assessed disability (disability index of the Health Assessment Questionnaire [HAQ]); and acute phase reactant C-reactive protein. Patients who discontinued or switched to open-label adalimumab prior to Week 26 were considered non-responders.

Patients were ACR70 responders if they had: >= 70% improvement in both tender joint count (68 joints) and in swollen joint count (66 joints) plus >=70% improvement in at least 3 of the 5 remaining ACR core measures: patient's assessment of pain; patient's global assessment of disease activity; physician's global assessment of disease activity; self-assessed disability (disability index of the Health Assessment Questionnaire [HAQ]); and acute phase reactant C-reactive protein. Patients who discontinued or switched to open-label adalimumab prior to Week 26 were considered non-responders.

Disease Activity Score (DAS28) is a combined index used to measure disease activity in patients with rheumatoid arthritis. Calculation of the DAS28 score used the tender joint count (28 joints), swollen joint count (28 joints), patient's global assessment of disease activity, and the erythrocyte sedimentation rate. DAS28(ESR) scores range from 0 (no disease activity) to 9 (maximal disease activity); decrease is indicative of improvement in disease activity.

Disease Activity Score (DAS28) is a combined index used to measure disease activity in patients with rheumatoid arthritis. Calculation of the DAS28 score used the tender joint count (28 joints), swollen joint count (28 joints), patient's global assessment of disease activity, and the erythrocyte sedimentation rate. DAS28(ESR) scores range from 0 (no disease activity) to 9 (maximal disease activity); decrease is indicative of improvement in disease activity. DAS28(ESR) score <2.6 was defined as clinical remission of disease.

Adverse events were collected at designated study visits for all participants who were randomized and received at least 1 dose of study drug. The number of participants who experienced any adverse event (serious or non-serious) while receiving double-blind study drug is summarized. See the Reported Adverse Event section for details.

Modified Total Sharp Score (mTSS) is a measure of joint health, used in evaluation of inhibition of radiographic progression of disease. Digitized X-rays of hands and feet were obtained then scored in a blinded manner: for erosions (0 [no damage] to 5 [complete collapse or total destruction of joint]) and for joint space narrowing (0 [no damage] to 4 [complete luxation of joint]). Scores were added, giving total mTSS score (0 [normal] to 380 [maximal disease]). Large positive change in mTSS indicates diseae progression; small positive/no change indicates slowing/halting of disease progression.

Patients were ACR20 responders if they had: >=20% improvement in both tender joint count (68 joints) and in swollen joint count (66 joints) plus >=20% improvement in at least 3 of the 5 remaining ACR core measures: patient's assessment of pain; patient's global assessment of disease activity; physician's global assessment of disease activity; self-assessed disability (disability index of the Health Assessment Questionnaire (HAQ); and acute phase reactant C-reactive protein.

Patients were ACR50 responders if they had: >=50% improvement in both tender joint count (68 joints) and in swollen joint count (66 joints) plus >=50% improvement in at least 3 of the 5 remaining ACR core measures: patient's assessment of pain; patient's global assessment of disease activity; physician's global assessment of disease activity; self-assessed disability (disability index of the Health Assessment Questionnaire (HAQ); and acute phase reactant C-reactive protein.

Patients were ACR70 responders if they had: >=70% improvement in both tender joint count (68 joints) and in swollen joint count (66 joints) plus >=70% improvement in at least 3 of the 5 remaining ACR core measures: patient's assessment of pain; patient's global assessment of disease activity; physician's global assessment of disease activity; self-assessed disability (disability index of the Health Assessment Questionnaire (HAQ); and acute phase reactant C-reactive protein.

Disease Activity Score (DAS28) is a combined index used to measure disease activity in patients with rheumatoid arthritis. Calculation of the DAS28 score used the tender joint count (28 joints), swollen joint count (28 joints), patient's global assessment of disease activity, and the erythrocyte sedimentation rate. DAS28(ESR) scores range from 0 (no disease activity) to 9 (maximal disease activity); decrease is indicative of improvement in disease activity.

Disease Activity Score (DAS28) is a combined index used to measure disease activity in patients with rheumatoid arthritis. Calculation of the DAS28 score used the tender joint count (28 joints), swollen joint count (28 joints), patient's global assessment of disease activity, and the erythrocyte sedimentation rate. DAS28(ESR) scores range from 0 (no disease activity) to 9 (maximal disease activity); decrease is indicative of improvement in disease activity. DAS28(ESR) score <2.6 was defined as clinical remission of disease.

Adverse events were collected at designated study visits for all participants who were randomized and received at least 1 dose of adalimumab. The number of participants who experienced any adverse event (serious or non-serious) while receiving any adalimumab during the study (double-blind adalimumab and/or open-label) is summarized. See the Reported Adverse Event section for details.

Participants received double-blind adalimumab administered subcutaneously (SC) every other week (eow) for 26 weeks followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants also received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC) every other week (eow) for 26 weeks followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind adalimumab 40 mg administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind adalimumab 40 mg administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind adalimumab 40 mg administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind adalimumab 40 mg administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind adalimumab 40 mg administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind adalimumab 40 mg administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind adalimumab 40 mg administered subcutaneously (SC) every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label adalimumab 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.

Participants received double-blind placebo administered subcutaneously (SC every other week (eow) and then open-label adalimumab 40 mg SC eow as rescue treatment (as eligible) to complete 26 weeks, followed by open-label 40 mg SC eow for up to 26 weeks. Participants received concomitant methotrexate 6 to 8 mg administered orally weekly.