Participants with at least 1 treatment with biologic agent not equal missing and which is not ongoing or with a stop date lower or equal to first TCZ administration had IR to biologic treatment. Participants with at least 1 treatment with DMARDs with a stop date lower or equal to first TCZ administration had IR to DMARDs. Participants with a biologic and DMARDs interruption or with a biologic interruption and ongoing treatment with DMARDs were classified in "IR to biologic group". Participants with DMARDs interruption or ongoing DMARDs and adding TCZ without a biologic interruption were classified in the "DMARDs intolerance and/or IR" group.

Time elapsed from diagnosis of RA in years was calculated as the (difference between the date of enrollment visit and the date of first diagnosis of RA) divided by 365.25.

Participants measured the pain intensity due to RA on a 100 millimeter (mm) VAS, where the responses were on a continuous range from 0 mm = no pain to 100 mm = unbearable pain.

The PGH was measured using a 100 mm VAS, where the responses were on a continuous range from 0 mm = managing very well to 100 mm = managing very poorly.

The PhGH was measured on a 100 mm VAS, where 0 mm = no arthritis activity to 100 mm = extremely active arthritis.

The participant assessment of morning stiffness was measured using a ruler on a 100 mm VAS, where the responses were on a continuous range from 0 mm = no stiffness and 100 mm = maximum stiffness.

Participants measured the level of fatigue due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no fatigue to 100 mm = extreme fatigue.

The HAQ-DI is a questionnaire that measures functional status (disability) and health-related quality of life (QoL). It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip, and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0 = without any difficulty to 3 = unable to do. Total score for HAQ-DI is the average of all questions and ranges from 0 to 3, where higher scores represent higher disease activity.

TJC was determined by examining 28 joints and identifying the joints that were painful under pressure or to passive motion. Tenderness was recorded on the joint assessment form at baseline; no tenderness = 0 and tenderness = 1.

SJC was determined by examining 28 joints and identifying when swelling was present. Swelling was recorded on the joint assessment form at baseline; no swelling = 0 and swelling = 1.

ESR is a laboratory test that provides a non-specific measure of inflammation. The test assesses the rate at which red blood cells fall in a test tube. Normal range is 0-30 millimeter per hour (mm/hour). A decrease in the level indicates reduction in inflammation and therefore improvement.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement.

Extra-articular systemic features referred to anemia, fatigue as well as a wide range of co-morbidities such as osteoporosis and other iatrogenic complications. Percentage of participants with any of the extra-articular systemic feature are reported.

RF is the auto antibody directed against immunoglobulin G and its concentration is observed in human serum or plasma. RF value higher than 20 units per milliliter is considered positive.

Duration of morning stiffness was defined as the time elapsed between the time of usual awakening (even if not in the morning) and the time the participant was able to resume normal activities without stiffness. The participant reported the duration of morning stiffness in the case report form by ticking 1 of the following categories: no morning stiffness, less than (<) 30 minutes, 30 - 60 minutes, 60 - 120 minutes, 120 - 240 minutes, greater than (>) 240 minutes, and the whole day. 'Not estimable' represented that the participants were not able to quantify it.

Number of participants with TCZ dose change (increase or decrease with respect to starting dose) was reported by reason for change.

The number of TCZ dose modifications per participant was calculated as the number of times that the participant changed the prescribed dose with respect to the dose planned at enrollment/previous administration. If the participant did not change the prescribed dose, the values were set at missing.

The time elapsed in days between TCZ infusions was calculated as the difference between the date of TCZ infusion and the date of the previous administration.

The percentage of participants with at least one infusion interruption was reported as "Yes". Participants with unknown infusion interruption were set to "No".

The percentage of participants with at least one TCZ reintroduction was reported as "Yes". Participants with unknown TCZ reintroduction were set to "No".

DAS28 score is a measurement of RA activity on a 0 to 10 scale, with higher scores representing higher disease activity, and calculated as DAS28 = 0.56 x √TJC28 + 0.28 x √SJC28 + 0.36 x natural logarithm (ln) (CRP + 1) + 0.014 x PGH + 0.96, where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, CRP = serum concentration of c-reactive protein (after converting units to mg/dL), PGH = patient global assessment of disease activity, which was measured on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly (√ = square root). A score of < 2.6 represents clinical remission, a score of greater than or equal to (≥) 2.6 and less than or equal to (≤) 3.2 represents low disease activity, a score of > 3.2 and ≤ 5.1 represents moderate disease activity and a score of > 5.1 represents high (or severe) disease activity. Change from baseline = DAS28 at Month X - DAS28 at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

SDAI is a combined index for measuring disease activity in RA and calculated as SDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm) + CRP (in mg/dL), where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 = managing very well and 100 = managing very poorly, PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = no arthritis activity and 100 mm = extremely active arthritis, CRP = serum concentration of C-reactive protein. SDAI total score ranged from 0-86. Higher scores represent greater disease activity. SDAI scores of ≤ 3.3 represents clinical remission, ≤ 11.0 represents low disease activity , ≤ 26.0 represents moderate disease activity, and > 26.0 represents high (or severe) disease activity. Change from baseline = SDAI score at Month X - SDAI score at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

The CDAI is a combined index for measuring disease activity in RA and calculated as CDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm), where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 = managing very well and 100 = managing very poorly, and PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = no arthritis activity and 100 mm = extremely active arthritis. CDAI total score ranged from 0-76. Higher scores indicate greater disease activity. CDAI score of ≤ 2.8 represents clinical remission, score of ≤ 10.0 represents low disease activity, score of ≤ 22.0 represents moderate disease activity, and score of > 22.0 represents high (or severe) disease activity. Change from baseline = CDAI score at Month X - CDAI score at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

DAS28 score is a measurement of RA activity on a 0 to 10 scale and calculated as DAS28 = 0.56 x √TJC28 + 0.28 x √SJC28 + 0.36 x ln(CRP + 1) + 0.014 x PGH + 0.96, where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, CRP = serum concentration of c-reactive protein (after converting units to mg/dL), PGH = patient's global assessment of disease activity, which was measured on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly. Higher scores represent greater disease activity. A score of < 2.6 represents clinical remission, a score of ≥ 2.6 and ≤ 3.2 represents low disease activity, a score of >3.2 and ≤ 5.1 represents moderate disease activity, and a score of > 5.1 represents high (or severe) disease activity.

SDAI is a combined index for measuring disease activity in RA and calculated as SDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm) + CRP (in mg/dL), where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly, PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 = no arthritis activity and 100 = extremely active arthritis, CRP = serum concentration of C-reactive protein. SDAI total score ranged from 0-86. Higher scores represent greater disease activity. SDAI scores of ≤ 3.3 represents clinical remission, ≤ 11.0 represents low disease activity, ≤ 26.0 represents moderate disease activity, and > 26.0 represents high (or severe) disease activity.

CDAI is a combined index for measuring disease activity in RA and calculated as CDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm), where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly, and PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = no arthritis activity and 100 mm = extremely active arthritis. CDAI total score ranged from 0-76. Higher scores indicate greater disease activity. CDAI score of ≤ 2.8 represents clinical remission, score of ≤ 10.0 represents low disease activity, score of ≤ 22.0 represents moderate disease activity, and score of > 22.0 represents high (or severe) disease activity.

ACR20, 50, 70 or 90 response = an improvement of ≥20%, ≥50%, ≥70% or ≥90% respectively, as compared to baseline in TJC28 and SJC28, and 20/50/70/90%, improvement in at least 3 of 5 following measures: Patient's Assessment of Pain over previous 24 hours, PGH, PhGH, HAQ, and acute phase reactant (either CRP or ESR). TJC and SJC, based on 28-joint assessments. Number of tender joints and swollen joints were recorded on joint assessment form at baseline; no tenderness = 0 and tenderness = 28, no swelling = 0 and swelling = 28, respectively. HAQ measures functional status (disability) and health-related QoL with 20 questions, summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip and common activities over past week, 0= without difficulty to 3= unable to do. Patient's assessment of pain assessed using VAS; 0 mm = no pain, 100 mm = unbearable pain; PGH and PhGH, assessed using VAS; 0 mm = no disease activity, 100 mm = maximum disease activity.

TJC was determined by examining 28 joints and identified the joints that were painful under pressure or to passive motion. The number of tender joints was recorded on the joint assessment form at baseline and at Month 6. No tenderness = 0 and tenderness = 1.

SJC was determined by examination of 28 joints and identifying when swelling was present. The number of swollen joints was recorded on the joint assessment form at baseline and at Month 6. No swelling = 0 and swelling = 1.

The PGH was measured using a 100 mm VAS, where the responses were on a continuous range from 0 mm = managing very well and 100 mm = managing very poorly.

The PhGH was evaluated using a 100 mm VAS where 0 mm = no arthritis activity and 100 mm = extremely active arthritis. Higher scores indicated increased level of disease.

Participants measured the pain intensity due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no pain to 100 mm = unbearable pain.

The HAQ-DI is a questionnaire that measures functional status (disability) and health-related QoL. It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0 = without any difficulty to 3 = unable to do.Total score for HAQ-DI is the average of all the questions, which ranges from 0 to 3, where higher scores represent higher disease activity.

Participants measured the level of fatigue due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no fatigue to 100 mm = extreme fatigue.

The participant assessment of morning stiffness was measured using a ruler on a 100 mm VAS, where the responses were on a continuous range from 0 mm = no stiffness and 100 mm = maximum stiffness.

The HAQ-DI is a questionnaire that measures functional status (disability) and health-related QoL. It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip, and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0 = without any difficulty to 3 = unable to do. Total score for HAQ-DI is the average of all the questions, which ranges from 0 to 3, where higher scores represent higher disease activity. HAQ-DI clinically meaningful improvement is defined as decrease in HAQ total score from baseline of greater or equal to 0.22 points.

Clinical response was assessed according to EULAR criteria that classified the participant according to individual changes in DAS28 score as good, moderate, or no response. DAS28 score is a measurement of RA activity on 0 to 10 scale and calculated as DAS28= 0.56 x √TJC28 + 0.28 x √SJC28 + 0.36 x ln(CRP + 1) + 0.014 x PGH + 0.96, where TJC28= tender joint count on 28 units, SJC28= swollen joint count on 28 units, CRP= serum concentration of C-reactive protein (after converting units to mg/dL), PGH= patient's global assessment of disease activity measured on a 100 mm VAS, where 0 mm= managing very well and 100 mm= managing very poorly. Good responders experienced change (chg) from baseline (BL) of >1.2 with DAS28 score ≤ 3.2, moderate responders experienced chg from BL >1.2 with DAS28 score > 3.2 to ≤ 5.1 or a chg from BL > 0.6 to ≤ 1.2 with DAS28 score of ≤ 5.1. No responders experienced chg from BL < 0.6 regardless initial DAS28 score or > 0.6 to ≤ 1.2 with DAS28 score of > 5.1.

DMARDs that met the criteria for "concomitant medications" were selected. The time to DMARD dose reduction was calculated as the difference between date of dose reduction and the date of first TCZ infusion. For participants presenting more than 1 DMARD dose reduction, only the first dose reduction was considered.

DMARDs that met the criteria for "concomitant medications" were selected. The time to DMARD withdrawal was calculated as the difference between date of withdrawal and the date of first TCZ infusion.

DMARDs that met the criteria for "concomitant medications" were selected. All treatments with DMARDs interrupted after the first TCZ infusion were selected.

Steroids that met the criteria for "concomitant medications" were selected. The time to steroid dose reduction was calculated as the difference between date of dose reduction and the date of first TCZ infusion. For participants presenting more than one steroid dose reduction, only the first dose reduction was considered.

Steroids that met the criteria for "concomitant medications" were selected. The time to steroid dose withdrawal was calculated as the difference between date of withdrawal and the date of first TCZ infusion.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement. Change from baseline = CRP level at Month X - CRP level at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

ESR is a laboratory test that provides a non-specific measure of inflammation. The test assesses the rate at which red blood cells fall in a test tube. Normal range is 0-30 mm/hr. A decrease in the level indicates reduction in inflammation and therefore improvement. Change from baseline = ESR level at Month X - ESR level at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement. DAS28 scale ranges from 0 to 10, where higher scores represent higher disease activity. DAS28 is calculated as follows: DAS28 = 0.56 x √TJC28 + 0.28 x √SJC28 + 0.36 x ln(CRP + 1) + 0.014 x PGH + 0.96, A score of < 2.6 represents clinical remission. SDAI is a combined index for measuring disease activity in RA and calculated as SDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm) + CRP (in mg/dL). A SDAI score of ≤ 3.3 represents clinical remission. CDAI is a combined index for measuring disease activity in RA and calculated as CDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm). A CDAI score of ≤ 2.8 represents clinical remission.

DAS28 scale ranges from 0 to 10, and calculated as DAS28 = 0.56 x √TJC28 + 0.28 x √SJC28 + 0.36 x ln(CRP + 1) + 0.014 x PGH + 0.96, where TJC28 and SJC28 = tender joint and swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly, CRP = serum concentration of C-reactive protein. A score of < 2.6 represents clinical remission. SDAI is a combined index for measuring disease activity in RA and calculated as SDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm) + CRP (in mg/dL), where PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = no arthritis activity and 100mm = extremely active arthritis. A SDAI score of ≤ 3.3 represents clinical remission. CDAI is a combined index for measuring disease activity in RA and calculated as CDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm). A CDAI score of ≤ 2.8 represents clinical remission.

Morning stiffness was defined by the time elapsed between the time of usual awakening (even if not in the morning) and the time the participant was able to resume normal activities without stiffness. The participant assessed morning stiffness based on the following criteria:

1. Presence of participant's joints stiff when woke up that day, measured as yes (stiffness present) or no (stiffness not present);
2. Duration of morning stiffness, measured by ticking 1 of the six categories: < 30 minutes, 30 - 60 minutes, 60 - 120 minutes, 120 - 240 minutes, > 240 minutes, and the whole day;
3. Severity of morning stiffness measured using a ruler on a 100 mm VAS where the responses were on a continuous range from 0 mm = no stiffness to 100 mm = maximum stiffness.

'Not estimable' represented that the participants were not able to quantify it. 'Not done' represented that the assessment was not performed.

Duration of morning stiffness was defined as the time elapsed between the time of usual awakening (even if not in the morning) and the time the participant was able to resume normal activities without stiffness. The participant reported the duration of morning stiffness in the case report form by ticking 1 of the following categories: no morning stiffness, < 30 minutes, 30 - 60 minutes, 60 - 120 minutes, 120 - 240 minutes, > 240 minutes, and the whole day. 'Not estimable' represented that the participants were not able to quantify it. 'Not done' represented that the assessment was not performed.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement. The participant reported the duration of morning stiffness in the case report form by ticking the categories: ≤ 30 minutes and > 30 minutes.

Morning stiffness was defined as the time elapsed between the time of usual awakening (even if not in the morning) and the time the participant was able to resume normal activities without stiffness. The participant reported the duration of morning stiffness in the case report form by ticking the categories: ≤ 30 minutes and > 30 minutes.

The test for CRP is laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in level of CRP indicates reduction in inflammation and therefore improvement. HAQ-DI is a questionnaire that measures functional status (disability) and health-related QoL. It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0 = without any difficulty to 3 = unable to do. Total score is average of all questions, which ranges from 0 to 3, where higher scores represent higher disease activity. The Pearson and Spearman correlation coefficients can range in value from -1 to +1.

CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in level of CRP indicates reduction in inflammation and therefore improvement. HAQ-DI is a questionnaire that measures functional status (disability) and health-related QoL. It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0= without any difficulty to 3= unable to do. Total score is the average of all questions, which ranges from 0 to 3, where higher scores represent higher disease activity. The Pearson and Spearman correlation coefficients can range in value from -1 to +1.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement. Participants measured the level of fatigue due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no fatigue to 100 mm = extreme fatigue. The Pearson and Spearman correlation coefficients can range in value from -1 to +1.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement. Participants measured the level of fatigue due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no fatigue to 100 mm = extreme fatigue. The Pearson and Spearman correlation coefficients can range in value from -1 to +1.

The HAQ-DI is a questionnaire that measures functional status (disability) and health-related QoL. It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene,reach, grip and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0 = without any difficulty to 3 = unable to do. Total score is the average of all questions, which ranges from 0 to 3, where higher scores represent higher disease activity. The Pearson and Spearman correlation coefficients can range in value from -1 to +1.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement. Morning stiffness was defined as the time elapsed between the time of usual awakening (even if not in the morning) and the time the participant was able to resume normal activities without stiffness. The participant reported the duration of morning stiffness in the case report form by ticking 1 of the following categories: no morning stiffness, < 30 minutes, 30 - 60 minutes, 60 - 120 minutes, 120 - 240 minutes, > 240 minutes, and the whole day. The Pearson and Spearman correlation coefficients can range in value from -1 to +1.

Participants measured the level of fatigue due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no fatigue to 100 mm = extreme fatigue. The Pearson and Spearman correlation coefficients can range in value from -1 to +1.

TCZ dose at Month 6 was calculated over the total number of participants evaluable for the primary objective and who did not interrupt TCZ. Percentage of participants on TCZ dose at Month 6 was calculated as the [(participants with specified TCZ dose at 6 months) divided by (participants who did not interrupt TCZ at Month 6)] multiplied by 100.

All enrolled participants evaluable for primary objective and who did not interrupt TCZ at Month 6.

Participants with at least 1 treatment with biologic agent not equal missing and which is not ongoing or with a stop date lower or equal to first TCZ administration had IR to biologic treatment. Participants with at least 1 treatment with DMARDs with a stop date lower or equal to first TCZ administration had IR to DMARDs. Participants with a biologic and DMARDs interruption or with a biologic interruption and ongoing treatment with DMARDs were classified in "IR to biologic group". Participants with DMARDs interruption or ongoing DMARDs and adding TCZ without a biologic interruption were classified in the "DMARDs intolerance and/or IR" group.

All enrolled participants evaluable for primary objective.

Time elapsed from diagnosis of RA in years was calculated as the (difference between the date of enrollment visit and the date of first diagnosis of RA) divided by 365.25.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

Participants measured the pain intensity due to RA on a 100 millimeter (mm) VAS, where the responses were on a continuous range from 0 mm = no pain to 100 mm = unbearable pain.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The PGH was measured using a 100 mm VAS, where the responses were on a continuous range from 0 mm = managing very well to 100 mm = managing very poorly.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The PhGH was measured on a 100 mm VAS, where 0 mm = no arthritis activity to 100 mm = extremely active arthritis.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The participant assessment of morning stiffness was measured using a ruler on a 100 mm VAS, where the responses were on a continuous range from 0 mm = no stiffness and 100 mm = maximum stiffness.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

Participants measured the level of fatigue due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no fatigue to 100 mm = extreme fatigue.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The HAQ-DI is a questionnaire that measures functional status (disability) and health-related quality of life (QoL). It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip, and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0 = without any difficulty to 3 = unable to do. Total score for HAQ-DI is the average of all questions and ranges from 0 to 3, where higher scores represent higher disease activity.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

TJC was determined by examining 28 joints and identifying the joints that were painful under pressure or to passive motion. Tenderness was recorded on the joint assessment form at baseline; no tenderness = 0 and tenderness = 1.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

SJC was determined by examining 28 joints and identifying when swelling was present. Swelling was recorded on the joint assessment form at baseline; no swelling = 0 and swelling = 1.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

ESR is a laboratory test that provides a non-specific measure of inflammation. The test assesses the rate at which red blood cells fall in a test tube. Normal range is 0-30 millimeter per hour (mm/hour). A decrease in the level indicates reduction in inflammation and therefore improvement.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

Extra-articular systemic features referred to anemia, fatigue as well as a wide range of co-morbidities such as osteoporosis and other iatrogenic complications. Percentage of participants with any of the extra-articular systemic feature are reported.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

RF is the auto antibody directed against immunoglobulin G and its concentration is observed in human serum or plasma. RF value higher than 20 units per milliliter is considered positive.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

Duration of morning stiffness was defined as the time elapsed between the time of usual awakening (even if not in the morning) and the time the participant was able to resume normal activities without stiffness. The participant reported the duration of morning stiffness in the case report form by ticking 1 of the following categories: no morning stiffness, less than (<) 30 minutes, 30 - 60 minutes, 60 - 120 minutes, 120 - 240 minutes, greater than (>) 240 minutes, and the whole day. 'Not estimable' represented that the participants were not able to quantify it.

All enrolled participants evaluable for primary objective.

Number of participants with TCZ dose change (increase or decrease with respect to starting dose) was reported by reason for change.

All enrolled participants evaluable for the primary objective and had TCZ dose modification.

The number of TCZ dose modifications per participant was calculated as the number of times that the participant changed the prescribed dose with respect to the dose planned at enrollment/previous administration. If the participant did not change the prescribed dose, the values were set at missing.

All enrolled participants evaluable for primary objective.

The time elapsed in days between TCZ infusions was calculated as the difference between the date of TCZ infusion and the date of the previous administration.

All enrolled participants evaluable for primary objective. Here, Number of participants analyzed = participants evaluable for the outcome measure and number analyzed = participants with available data for specified category.

The percentage of participants with at least one infusion interruption was reported as "Yes". Participants with unknown infusion interruption were set to "No".

All enrolled participants evaluable for primary objective.

All enrolled participants evaluable for primary objective who discontinued TCZ.

The percentage of participants with at least one TCZ reintroduction was reported as "Yes". Participants with unknown TCZ reintroduction were set to "No".

All enrolled participants evaluable for primary objective.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

DAS28 score is a measurement of RA activity on a 0 to 10 scale, with higher scores representing higher disease activity, and calculated as DAS28 = 0.56 x √TJC28 + 0.28 x √SJC28 + 0.36 x natural logarithm (ln) (CRP + 1) + 0.014 x PGH + 0.96, where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, CRP = serum concentration of c-reactive protein (after converting units to mg/dL), PGH = patient global assessment of disease activity, which was measured on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly (√ = square root). A score of < 2.6 represents clinical remission, a score of greater than or equal to (≥) 2.6 and less than or equal to (≤) 3.2 represents low disease activity, a score of > 3.2 and ≤ 5.1 represents moderate disease activity and a score of > 5.1 represents high (or severe) disease activity. Change from baseline = DAS28 at Month X - DAS28 at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

SDAI is a combined index for measuring disease activity in RA and calculated as SDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm) + CRP (in mg/dL), where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 = managing very well and 100 = managing very poorly, PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = no arthritis activity and 100 mm = extremely active arthritis, CRP = serum concentration of C-reactive protein. SDAI total score ranged from 0-86. Higher scores represent greater disease activity. SDAI scores of ≤ 3.3 represents clinical remission, ≤ 11.0 represents low disease activity , ≤ 26.0 represents moderate disease activity, and > 26.0 represents high (or severe) disease activity. Change from baseline = SDAI score at Month X - SDAI score at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The CDAI is a combined index for measuring disease activity in RA and calculated as CDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm), where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 = managing very well and 100 = managing very poorly, and PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = no arthritis activity and 100 mm = extremely active arthritis. CDAI total score ranged from 0-76. Higher scores indicate greater disease activity. CDAI score of ≤ 2.8 represents clinical remission, score of ≤ 10.0 represents low disease activity, score of ≤ 22.0 represents moderate disease activity, and score of > 22.0 represents high (or severe) disease activity. Change from baseline = CDAI score at Month X - CDAI score at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

DAS28 score is a measurement of RA activity on a 0 to 10 scale and calculated as DAS28 = 0.56 x √TJC28 + 0.28 x √SJC28 + 0.36 x ln(CRP + 1) + 0.014 x PGH + 0.96, where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, CRP = serum concentration of c-reactive protein (after converting units to mg/dL), PGH = patient's global assessment of disease activity, which was measured on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly. Higher scores represent greater disease activity. A score of < 2.6 represents clinical remission, a score of ≥ 2.6 and ≤ 3.2 represents low disease activity, a score of >3.2 and ≤ 5.1 represents moderate disease activity, and a score of > 5.1 represents high (or severe) disease activity.

All enrolled participants evaluable for primary objective. Here, Number of participants analyzed= participants evaluable for this outcome and number analyzed = participants with available data for specified category.

SDAI is a combined index for measuring disease activity in RA and calculated as SDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm) + CRP (in mg/dL), where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly, PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 = no arthritis activity and 100 = extremely active arthritis, CRP = serum concentration of C-reactive protein. SDAI total score ranged from 0-86. Higher scores represent greater disease activity. SDAI scores of ≤ 3.3 represents clinical remission, ≤ 11.0 represents low disease activity, ≤ 26.0 represents moderate disease activity, and > 26.0 represents high (or severe) disease activity.

All enrolled participants evaluable for primary objective. Here, Number of participants analyzed = participants evaluable for the outcome measure and number analyzed = participants with available data for specified category.

CDAI is a combined index for measuring disease activity in RA and calculated as CDAI = TJC28 + SJC28 + PGH (in cm) + PhGH (in cm), where TJC28 = tender joint count on 28 units, SJC28 = swollen joint count on 28 units, PGH = patient's global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = managing very well and 100 mm = managing very poorly, and PhGH = physician global assessment of disease activity, assessed on a 100 mm VAS, where 0 mm = no arthritis activity and 100 mm = extremely active arthritis. CDAI total score ranged from 0-76. Higher scores indicate greater disease activity. CDAI score of ≤ 2.8 represents clinical remission, score of ≤ 10.0 represents low disease activity, score of ≤ 22.0 represents moderate disease activity, and score of > 22.0 represents high (or severe) disease activity.

All enrolled participants evaluable for primary objective. Here, Number of participants analyzed= participants evaluable for the outcome measure and number analyzed = participants with available data for specified category.

ACR20, 50, 70 or 90 response = an improvement of ≥20%, ≥50%, ≥70% or ≥90% respectively, as compared to baseline in TJC28 and SJC28, and 20/50/70/90%, improvement in at least 3 of 5 following measures: Patient's Assessment of Pain over previous 24 hours, PGH, PhGH, HAQ, and acute phase reactant (either CRP or ESR). TJC and SJC, based on 28-joint assessments. Number of tender joints and swollen joints were recorded on joint assessment form at baseline; no tenderness = 0 and tenderness = 28, no swelling = 0 and swelling = 28, respectively. HAQ measures functional status (disability) and health-related QoL with 20 questions, summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip and common activities over past week, 0= without difficulty to 3= unable to do. Patient's assessment of pain assessed using VAS; 0 mm = no pain, 100 mm = unbearable pain; PGH and PhGH, assessed using VAS; 0 mm = no disease activity, 100 mm = maximum disease activity.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

TJC was determined by examining 28 joints and identified the joints that were painful under pressure or to passive motion. The number of tender joints was recorded on the joint assessment form at baseline and at Month 6. No tenderness = 0 and tenderness = 1.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

SJC was determined by examination of 28 joints and identifying when swelling was present. The number of swollen joints was recorded on the joint assessment form at baseline and at Month 6. No swelling = 0 and swelling = 1.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The PGH was measured using a 100 mm VAS, where the responses were on a continuous range from 0 mm = managing very well and 100 mm = managing very poorly.

All enrolled participants evaluable for the primary objective with available data for this outcome measure.

The PhGH was evaluated using a 100 mm VAS where 0 mm = no arthritis activity and 100 mm = extremely active arthritis. Higher scores indicated increased level of disease.

All enrolled participants evaluable for the primary objective with available data for this outcome measure.

Participants measured the pain intensity due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no pain to 100 mm = unbearable pain.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The HAQ-DI is a questionnaire that measures functional status (disability) and health-related QoL. It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0 = without any difficulty to 3 = unable to do.Total score for HAQ-DI is the average of all the questions, which ranges from 0 to 3, where higher scores represent higher disease activity.

All enrolled participants evaluable for the primary objective with available data for this outcome measure.

Participants measured the level of fatigue due to RA using a 100 mm VAS, where the responses were on a continuous range from 0 mm = no fatigue to 100 mm = extreme fatigue.

All enrolled participants evaluable for the primary objective with available data for this outcome measure.

The participant assessment of morning stiffness was measured using a ruler on a 100 mm VAS, where the responses were on a continuous range from 0 mm = no stiffness and 100 mm = maximum stiffness.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The HAQ-DI is a questionnaire that measures functional status (disability) and health-related QoL. It measures the participant's ability to perform everyday tasks. The index consists of 20 questions regarding the function of the upper and lower extremities. These questions are summarized in 8 categories: dressing and grooming, arising, eating, walking, hygiene, reach, grip, and common activities over past week. Each question was evaluated according to the degree of severity on a 4-point scale ranging from 0 = without any difficulty to 3 = unable to do. Total score for HAQ-DI is the average of all the questions, which ranges from 0 to 3, where higher scores represent higher disease activity. HAQ-DI clinically meaningful improvement is defined as decrease in HAQ total score from baseline of greater or equal to 0.22 points.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

Clinical response was assessed according to EULAR criteria that classified the participant according to individual changes in DAS28 score as good, moderate, or no response. DAS28 score is a measurement of RA activity on 0 to 10 scale and calculated as DAS28= 0.56 x √TJC28 + 0.28 x √SJC28 + 0.36 x ln(CRP + 1) + 0.014 x PGH + 0.96, where TJC28= tender joint count on 28 units, SJC28= swollen joint count on 28 units, CRP= serum concentration of C-reactive protein (after converting units to mg/dL), PGH= patient's global assessment of disease activity measured on a 100 mm VAS, where 0 mm= managing very well and 100 mm= managing very poorly. Good responders experienced change (chg) from baseline (BL) of >1.2 with DAS28 score ≤ 3.2, moderate responders experienced chg from BL >1.2 with DAS28 score > 3.2 to ≤ 5.1 or a chg from BL > 0.6 to ≤ 1.2 with DAS28 score of ≤ 5.1. No responders experienced chg from BL < 0.6 regardless initial DAS28 score or > 0.6 to ≤ 1.2 with DAS28 score of > 5.1.

All enrolled participants evaluable for primary objective. Here, Number of participants analyzed= participants evaluable for the outcome measure and number analyzed = participants with available data for specified category.

DMARDs that met the criteria for "concomitant medications" were selected. The time to DMARD dose reduction was calculated as the difference between date of dose reduction and the date of first TCZ infusion. For participants presenting more than 1 DMARD dose reduction, only the first dose reduction was considered.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

DMARDs that met the criteria for "concomitant medications" were selected. The time to DMARD withdrawal was calculated as the difference between date of withdrawal and the date of first TCZ infusion.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

DMARDs that met the criteria for "concomitant medications" were selected. All treatments with DMARDs interrupted after the first TCZ infusion were selected.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

Steroids that met the criteria for "concomitant medications" were selected. The time to steroid dose reduction was calculated as the difference between date of dose reduction and the date of first TCZ infusion. For participants presenting more than one steroid dose reduction, only the first dose reduction was considered.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

Steroids that met the criteria for "concomitant medications" were selected. The time to steroid dose withdrawal was calculated as the difference between date of withdrawal and the date of first TCZ infusion.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

The test for CRP is a laboratory measurement for evaluation of an acute phase reactant of inflammation through the use of an ultrasensitive assay. A decrease in the level of CRP indicates reduction in inflammation and therefore improvement. Change from baseline = CRP level at Month X - CRP level at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

All enrolled participants evaluable for primary objective with available data for this outcome measure.

ESR is a laboratory test that provides a non-specific measure of inflammation. The test assesses the rate at which red blood cells fall in a test tube. Normal range is 0-30 mm/hr. A decrease in the level indicates reduction in inflammation and therefore improvement. Change from baseline = ESR level at Month X - ESR level at baseline. Here X = 3 and 6 for Change at Months 3 and 6, respectively.

All enrolled participants evaluable for primary objective with available data for this outcome measure.