A Study Assessing the Safety and Efficacy of Sarilumab Added to Non-MTX DMARDs or as Monotherapy in Japanese Patients With Active Rheumatoid Arthritis (SARIL-RA-HARUKA)

Criteria for potentially clinically significant ECG abnormalities: * PR Interval: \>200 milliseconds (ms); \>200 ms and IFB \>=25%; \>220 ms; \>220 ms and IFB \>=25%; \>240 ms; \>240 ms and IFB \>=25% * QRS Interval: \>110 ms; \>110 ms and IFB \>=25%; \>120 ms; \>120 ms and IFB \>=25% * QT Interval: \>500 ms * QTc Bazett (QTc B): \>450 ms; \>480 ms; \>500 ms; IFB \>30 and \<=60 ms, IFB \>60 ms * QTc Fridericia (QTc F): \>450 ms; \>480 ms; \>500 ms; IFB \>30 and \<=60 ms; IFB \>60 ms

Time frame: Baseline up to Week 58

Population: Safety population included all randomized participants who actually received at least one dose or a partial dose of IMP analyzed according to the treatment actually received.

Criteria for potentially clinically significant abnormalities: * Sodium: \<=129 mmol/L; \>=160 mmol/L * Potassium: \<3 mmol/L; \>=5.5 mmol/L * Chloride: \<80 mmol/L; \>115 mmol/L

Time frame: Baseline up to Week 58

Population: Safety population included all randomized participants who actually received at least one dose or a partial dose of IMP analyzed according to the treatment actually received.

Criteria for potentially clinically significant abnormalities: * Hemoglobin: \<=115 g/L (Male\[M\]) or \<=95 g/L (Female\[F\]); \>=185 g/L (M) or \>=165 g/L (F); DFB \>=20 g/L * Hematocrit: \<=0.37 v/v (M) or \<=0.32 v/v (F); \>=0.55 v/v (M) or \>=0.5 v/v (F) * Red blood cells (RBC): \>=6 Tera/L * Platelets: \<50 Giga/L; \>=50 and \<100 Giga/L; \>=700 Giga/L * White blood cells (WBC): \<3.0 Giga/L (Non-Black \[NB\]) or \<2.0 Giga/L (Black \[B\]); \>=16.0 Giga/L * Neutrophils: \<1.5 Giga/L (NB) or \<1.0 Giga/L (B); \<1.0 Giga/L * Lymphocytes: \<0.5 Giga/L; \>=0.5 Giga/L and \<lower limit of normal (LLN); \>4.0 Giga/L * Monocytes: \>0.7 Giga/L * Basophils: \>0.1 Giga/L * Eosinophils: \>0.5 Giga/L or \>upper limit of normal (ULN) (if ULN \>=0.5 Giga/L)

Time frame: Baseline up to Week 58

Population: Safety population included all randomized participants who actually received at least one dose or a partial dose of IMP analyzed according to the treatment actually received.

Criteria for potentially clinically significant abnormalities: * Alanine Aminotransferase (ALT): \>1 ULN and \<=1.5 ULN; \>1.5 ULN and \<=3 ULN; \>3 ULN and \<=5 ULN; \>5 ULN and \<=10 ULN; \>10 ULN and \<=20 ULN; \>20 ULN * Aspartate aminotransferase (AST): \>1 ULN and \<=1.5 ULN; \>1.5 ULN and \<=3 ULN; \>3 ULN and \<=5 ULN; \>5 ULN and \<=10 ULN; \>10 ULN and \<=20 ULN; \>20 ULN * Alkaline phosphatase: \>1.5 ULN * Total bilirubin (TBILI): \>1.5 ULN; \>2 ULN * Conjugated bilirubin(CBILI): \>1.5 ULN * Unconjugated bilirubin: \>1.5 ULN * ALT \>3 ULN and TBILI \>2 ULN * CBILI \>35% TBILI and TBILI \>1.5 ULN * Albumin: \<=25 g/L

Time frame: Baseline up to Week 58

Population: Safety population included all randomized participants who actually received at least one dose or a partial dose of IMP analyzed according to the treatment actually received.

Criteria for potentially clinically significant abnormalities: * Glucose: \<=3.9 mmol/L and \<LLN; \>=11.1 mmol/L (unfasted \[unfas\]) or \>=7 mmol/L (fasted \[fas\]) * Hemoglobin A1c (HbA1c): \>8% * Total cholesterol: \>=6.2 mmol/L; \>=7.74 mmol/L * LDL cholesterol: \>=4.1 mmol/L; \>=4.9 mmol/L * Triglycerides: \>=4.6 mmol/L; \>=5.6 mmol/L

Time frame: Baseline up to Week 58

Population: Safety population included all randomized participants who actually received at least one dose or a partial dose of IMP analyzed according to the treatment actually received.

Criteria for potentially clinically significant abnormalities: * Creatinine: \>=150 micromol/L (adults); \>=30% change from baseline, \>=100% change from baseline * Creatinine clearance: \<15 mL/min; \>=15 to \<30 mL/min; \>=30 to \<60 mL/min; \>=60 to \<90 mL/min * Blood urea nitrogen: \>=17 mmol/L * Uric acid: \<120 micromol/L; \>408 micromol/L

Time frame: Baseline up to Week 58

Population: Safety population included all randomized participants who actually received at least one dose or a partial dose of IMP analyzed according to the treatment actually received.

Criteria for potentially clinically significant vital sign abnormalities: * Systolic blood pressure (SBP) supine: \<=95 mmHg and decrease from baseline (DFB) \>=20 mmHg; \>=160 mmHg and increase from baseline (IFB) \>=20 mmHg * Diastolic blood pressure (DBP) supine: \<=45 mmHg and DFB \>=10 mmHg; \>=110 mmHg and IFB ≥10 mmHg * SBP (Orthostatic): \<=-20 mmHg * DBP (Orthostatic): \<=-10 mmHg * Heart rate (HR) supine: \<=50 beats per minute (bpm) and DFB \>=20 bpm; \>=120 bpm and IFB \>=20 bpm * Weight: \>=5% DFB; \>=5% IFB

Time frame: Baseline up to Week 58

Population: Safety population included all randomized participants who actually received at least one dose or a partial dose of IMP analyzed according to the treatment actually received.

Adverse event (AE) was defined as any untoward medical occurrence in a participant who received IMP and did not necessary have to had a causal relationship with treatment. All AEs that occurred from the first dose of the IMP administration up to 6 weeks after last dose of treatment (up to Week 58) were considered as TEAEs. SAEs were AEs resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly or a medically important event. TEAEs included both SAEs and non-SAEs.

Time frame: Baseline up to Week 58

Population: Safety population included all randomized participants who actually received at least one dose or a partial dose of IMP analyzed according to the treatment actually received.

DAS28-CRP is a composite score that contains 4 variables: TJC (based on 28 joints), SJC (based on 28 joints), participant's assessment of general health on VAS (range 0 \[very well\] to 100 mm \[extremely bad\]) and CRP (mg/L). DAS28-CRP total score ranges from 2-10 with a lower score indicating less disease activity. A DAS28-CRP above 5.1 indicates high disease activity, whereas below 3.2 indicates low disease activity and below 2.6 as disease remission.

Time frame: Baseline, Week 52

Population: mITT population included all randomized participants who received at least one dose of IMP, irrespective of compliance with the study protocol and procedures. Here 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

HAQ-DI assessed the degree of difficulty participants experienced in 8 daily living activity domains during a week: dressing/grooming, arising, eating, walking, hygiene, reach, grip, and other activities. Each activity category consisted of 2-3 items. Each items's difficulty was scored from 0-3 (0=no difficulty, 1=some difficulty, 2=much difficulty, 3=unable to do). Overall HAQ-DI score was computed as the sum of domain scores divided by the number of domains answered, providing a score from 0-3. Low scores denoted improvement of disability/lower degree of domain difficulty.

Time frame: Baseline, Week 52

Population: mITT population included all randomized participants who received at least one dose of IMP, irrespective of compliance with the study protocol and procedures. Here 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

ACR response is a composite rating scale that includes 7 variables: tender joints count (TJC \[68 joints\]); swollen joints count (SJC \[66 joints\]); levels of an acute phase reactant (high sensitivity C-reactive protein \[hs-CRP level\]); participant's assessment of pain (measured on 0 \[no pain\]-100 mm \[worst pain\] visual analog scale \[VAS\]); participant's global assessment of disease activity (measured on 0 \[no arthritis activity\]-100 mm \[maximal arthritis activity\] VAS); physician's global assessment of disease activity (measured on 0 \[no arthritis activity\]-100 mm \[maximal arthritis activity\] VAS); participant's assessment of physical function (measured by Health Assessment Question-Disability Index \[HAQ-DI\], with scoring range of 0 \[better health\] - 3 \[worst health\]). ACR20/50/70 response is defined as at least 20/50/70% improvement in both TJC and SJC, and at least 20/50/70% improvement in at least 3 of the 5 other assessments, respectively.

Time frame: Week 52

Population: mITT population included all randomized participants who received at least one dose of IMP, irrespective of compliance with the study protocol and procedures.