An infusion reaction was defined as any adverse event (AE) that occurred during the infusion or during the 24 hours following the infusion and deemed possibly or probably related to tocilizumab.

Safety Analysis Set (SAS) Population: All randomized participants who received at least one infusion of tocilizumab.

All occurrences of participants who received at least 1 infusion of tocilizumab and then stopped tocilizumab infusions due to an AE or SAE were analyzed.

SAS Population

Participants that stopped the administration of tocilizumab and discontinued the study prematurely due to reasons other than an AE or SAE were analyzed.

SAS Population

Increased liver enzyme values defined as Alanine Aminotransferase (ALT) and/or Aspartate Aminotransferase (AST) values of >1.5 times, or >3 times, or >5 times over the ULN. Almost none of the participants had increased measurements of AST, thus only values of ALT were presented. None of the participants presented with increased values of ALT above 3 or 5 ULN at any of the visits.

ITT Completers is defined as a subset of the participants in the ITT population who completed all study visits.

ITT Completers with liver enzyme datasets for each analyzed visit

Increased levels of high density lipoproteins (HDL) equal to or greater than (≥)1.5 millimoles per liter (mmol/L), and low density lipoproteins (LDL) ≥4.1 mmol/L, and total cholesterol ≥5.1 mmol/L, are defined according to the Adult Treatment Panel III (ATP-III) guidelines.

ITT Completers

Improvement in Rheumatoid Arthritis (RA) disease activity was measured by the DAS28 score, which is an index combining measurements of swollen and tender joints, acute phase response High sensitivity C-Reactive Protein (hsCRP), and global assessment of disease activity by the participant. A clinically meaningful improvement was defined as a reduction of at least 1.2 units in the DAS28 score during the study period. A low disease activity was defined as a DAS28 score less than (<)3.2, and remission was defined as a DAS28 score <2.6.

ITT Completers

Improvement in RA disease activity was measured by the DAS28 score, which is an index combining measurements of swollen and tender joints, acute phase response hsCRP, and global assessment of disease activity by the participant. A clinically meaningful improvement was defined as a reduction of at least 1.2 units in the DAS28 score during the study period. A low disease activity was defined as a DAS28 score <3.2, and remission was defined as a DAS28 score <2.6.

ITT Completers

Improvement in RA disease activity was measured by the DAS28 score, which is an index combining measurements of swollen and tender joints, acute phase response hsCRP, and global assessment of disease activity by the participant. A clinically meaningful improvement was defined as a reduction of at least 1.2 units in the DAS28 score during the study period. A low disease activity was defined as a DAS28 score <3.2, and remission was defined as a DAS28 score <2.6.

ITT Completers

Improvement in RA disease activity was measured by the DAS28 score, which is an index combining measurements of swollen and tender joints, acute phase response hsCRP, and global assessment of disease activity by the participant. A clinically meaningful improvement was defined as a reduction of at least 1.2 units in the DAS28 score during the study period. A low disease activity was defined as a DAS28 score <3.2, and remission was defined as a DAS28 score <2.6.

ITT Completers; n = the number of participants analyzed for the given parameter at the specific visit.

ACR20 response is defined as an improvement of ≥20% in swollen joint count (SJC; 66 joints) and tender joint count (TJC; 68 joints) as well as ≥20% improvement in at least 3 of the following 5 remaining ACR assessments: Patient Global Assessment of Pain; Patient Global Assessment of Disease Activity; Physician Global Assessment of Disease Activity; Health Assessment Questionnaire - Disability Index (HAQ-DI); and acute phase reactive factors (Erythrocyte Sedimentation Rate [ESR] or C-Reactive Protein [CRP]).

ITT Completers

ACR50 response is defined as an improvement of ≥50% in SJC (66 joints) and TJC (68 joints) as well as ≥50% improvement in at least 3 of the following 5 remaining ACR assessments: Patient Global Assessment of Pain; Patient Global Assessment of Disease Activity; Physician Global Assessment of Disease Activity; HAQ-DI; and acute phase reactive factors (ESR or CRP).

ITT Completers

ACR70 response is defined as an improvement of ≥70% in SJC (66 joints) and TJC (68 joints) as well as ≥70% improvement in at least 3 of the following 5 remaining ACR assessments: Patient Global Assessment of Pain; Patient Global Assessment of Disease Activity; Physician Global Assessment of Disease Activity; HAQ-DI; and acute phase reactive factors (ESR or CRP).

ITT Completers

ACR90 response is defined as an improvement of ≥90% in SJC (66 joints) and TJC (68 joints) as well as ≥90% improvement in at least 3 of the following 5 remaining ACR assessments: Patient Global Assessment of Pain; Patient Global Assessment of Disease Activity; Physician Global Assessment of Disease Activity; HAQ-DI; and acute phase reactive factors (ESR or CRP).

ITT Completers

hsCRP is a marker for inflammation and is measured in milligrams per liter (mg/L). High levels of this protein indicate inflammation in diseases such as RA.

ITT Completers

M-HAQ is a self-reported, valid assessment of functional disability in RA. Assessment based on ability of participants to perform daily activities in 8 categories: dressing, arising, eating, walking, reaching, gripping, hygiene, and carrying out daily activities. Scores range 0 to 3; without any difficulty=0, with some difficulty=1, with much difficulty=2, unable to do=3.

ITT Completers

M-HAQ is a self-reported, valid assessment of functional disability in RA. Assessment based on ability of participants to perform daily activities in 8 categories: dressing, arising, eating, walking, reaching, gripping, hygiene, and carrying out daily activities. Scores range 0 to 3; without any difficulty=0, with some difficulty=1, with much difficulty=2, unable to do=3.

ITT Completers