All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study.

Concomitant therapy with oral corticosteroids (up 5 to 10 mg daily prednisone or equivalent) was permitted in the study. Reduction of oral corticosteroids was permitted, but not required, if a patient achieved at least a 50% improvement from baseline in both tender joint count and swollen joint count.

The data are reported for each 6-month period of the study where a month = 28 days. The last 6-month period is for months 96 through 101. The actually study duration in 28-day months was 98.85 months.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study.

Participants who entered this study from study WA17824 on tocilizumab monotherapy, who did not achieve a 50% reduction in tender and swollen joint counts from Baseline of study WA17824, could add methotrexate or another allowable disease-modifying anti-rheumatic drug, according to the investigator's practice and as tolerated by the patient, at any time during this study.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants from the core study WA17824 are included in the analysis.

Improvement must be seen in tender (68 assessed joints) and swollen joint counts (66 assessed joints) and in at least 3 of the following 5 parameters: Separate patient and physician assessments of patient disease activity in the previous 24 hours on a visual analog scale (VAS, the left end of the scale "no disease activity" [symptom-free and no arthritis symptoms], right end of the scale "maximum disease activity"); patient assessment of pain in the previous 24 hours on a VAS (left end of the scale "no pain", right end of the scale "unbearable pain"); Health Assessment Questionnaire-Disability Index (20 questions, 8 components: dressing/grooming, arising, eating, walking, hygiene, reach, grip, and activities, 0=without difficulty to 3=unable to do); and erythrocyte sedimentation rate.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

A major clinical response was defined as maintenance of an improvement of at least 70% in the American College of Rheumatology (ACR) score (ACR70) for at least 24 weeks. Improvement must be seen in tender (68 assessed joints) and swollen joint counts (66 assessed joints) and in at least 3 of the following 5 parameters: Separate patient and physician assessments of patient disease activity in the previous 24 hours on a visual analog scale (VAS, the left end of the scale "no disease activity" [symptom-free and no arthritis symptoms], right end of the scale "maximum disease activity"); patient assessment of pain in the previous 24 hours on a VAS (left end of the scale "no pain", right end of the scale "unbearable pain"); Health Assessment Questionnaire-Disability Index (20 questions, 8 components: dressing/grooming, arising, eating, walking, hygiene, reach, grip, and activities, 0=without difficulty to 3=unable to do); and erythrocyte sedimentation rate.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

Improvement must be seen in tender (68 assessed joints) and swollen joint counts (66 assessed joints) and in at least 3 of the following 5 parameters: Separate patient and physician assessments of patient disease activity in the previous 24 hours on a visual analog scale (VAS, the left end of the scale "no disease activity" [symptom-free and no arthritis symptoms], right end of the scale "maximum disease activity"); patient assessment of pain in the previous 24 hours on a VAS (left end of the scale "no pain", right end of the scale "unbearable pain"); Health Assessment Questionnaire-Disability Index (20 questions, 8 components: dressing/grooming, arising, eating, walking, hygiene, reach, grip, and activities, 0=without difficulty to 3=unable to do); and erythrocyte sedimentation rate.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

The number of swollen (66 assessed joints) and tender (68 assessed joints) joints was assessed. Joints were physically examined and classified as swollen/not swollen and tender/not tender by pressure and joint manipulation.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

Participant's made a global assessment of their current disease activity on a 100 mm horizontal visual analogue scale (VAS). The left end of the scale indicated "no disease activity" (symptom-free and no arthritis symptoms, score = 0) and the right end indicated "maximum disease activity" (maximum arthritis disease activity, score = 100). The participant's treating physician made a global assessment of the participant's current disease activity on a 100 mm horizontal VAS. The left end of the scale indicated "no disease activity" (symptom-free and no arthritis symptoms, score = 0) and the right end indicated "maximum disease activity" (maximum arthritis disease activity, score = 100). Participant's made an assessment of their current level of pain on a 100 mm horizontal VAS. The left end of the scale indicated "no pain" (score = 0) and the right end of the scale indicated "unbearable pain" (score = 100).

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

The Health Assessment Questionnaire-Disability Index (HAQ-DI), as a measure of functional ability, consists of 30 questions in 8 domains: Dressing/grooming, arising, eating, walking, hygiene, reach, grip, and activities. There are 4 possible responses to each question (0=without any difficulty, 1=with some difficulty, 2=with much difficulty, 3=unable to do). A domain score is the highest score in that domain. To calculate the overall score, the patient must have a domain score in at least 6 of the 8 domains. The HAQ-DI score is the sum of the domain scores divided by the number of domains that have a non-missing score and ranges from 0 (best) to 3 (worst). A higher score indicates less ability.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

Erythrocyte sedimentation rate (ESR) was determined locally.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

The DAS28 is a combined index for measuring disease activity in rheumatic arthritis (RA) and includes swollen and tender joint counts, erythrocyte sedimentation rate (ESR), and general health (GH) status. The index is calculated with the following formula: DAS28 = (0.56 × √(TJC28)) + (0.28 × √(SJC28)) + (0.7 × log(ESR)) + (0.014 × GH), where TJC28 = tender joint count and SJC28 = swollen joint count, each on 28 joints. GH = a patient's global assessment of disease activity in the previous 24 hours on a 100 mm visual analog scale (left end = no disease activity [symptom-free and no arthritis symptoms], right end = maximum disease activity [maximum arthritis disease activity]). When ESR equaled 0 mm/hr, it was set to 1 mm/hr. The DAS28 scale ranges from 0 to 10, where higher scores represent higher disease activity. A negative change score indicates improvement.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

A DAS-28 responder was defined as someone who met the European League Against Rheumatism [EULAR] criteria of a good or moderate response. A change of the DAS-28 score from Baseline was used to determine EULAR responses of good, moderate, or no response. For a post-baseline score ≤ 3.2, a change from baseline of < -1.2 was a good response, < -0.6 to ≥ -1.2 was a moderate response, and ≥ -0.6 was no response. For a post-baseline score > 3.2 to ≤ 5.1, a change from baseline of < -0.6 was a moderate response and ≥ -0.6 was no response. For a post-baseline score > 5.1, a change from baseline < -1.2 was a moderate response and ≥ -1.2 was no response. A good response could not be achieved for post-baseline scores > 3.2.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

A DAS-28 responder was defined as someone who met the European League Against Rheumatism [EULAR] criteria of a good or moderate response. A change of the DAS-28 score from Baseline was used to determine EULAR responses of good, moderate, or no response. For a post-baseline score ≤ 3.2, a change from baseline of < -1.2 was a good response, < -0.6 to ≥ -1.2 was a moderate response, and ≥ -0.6 was no response. For a post-baseline score > 3.2 to ≤ 5.1, a change from baseline of < -0.6 was a moderate response and ≥ -0.6 was no response. For a post-baseline score > 5.1, a change from baseline < -1.2 was a moderate response and ≥ -1.2 was no response. A good response could not be achieved for post-baseline scores > 3.2.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

The FACIT-F is a 13-item participant self-report questionnaire that assesses fatigue over the previous 7 days by scoring each item on a 5-point scale (0=Not at all, 1=A little bit, 2=Somewhat, 3=Quite a bit, 4=Very much). An overall FACIT-F score was obtained by summing the scores of all 13 items. The overall score ranged from 0 to 52. A lower score indicates less fatigue. A clinically relevant improvement in the FACIT-F score was defined as a ≥ 5-point increase from Baseline.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.

The SF-36 Health Survey uses participant-reported symptoms on 8 subscales to assess health-related quality of life (HRQoL). The Physical Component Summary (PCS) score summarizes the subscales Physical Functioning, Role-Physical, Bodily Pain, and General Health. The Mental Component Summary (MCS) score summarizes the subscales Vitality, Social Functioning, Role-Emotional, and Mental Health. Each score was scaled from 0 to 100 with a higher score indicating better HRQoL. A clinically relevant improvement in the Physical and Mental Component Scores of the SF-36 was defined as a ≥ 5-point increase from Baseline.

All-exposure population: All participants who entered this study and received at least 1 dose of tocilizumab in either this extension study or in a core study. Only participants with available data were included in the analysis.