An adverse event (AE) is defined as any untoward medical occurrence in a participant or clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered to be related to the medicinal product. An serious adverse event (SAE) is any untoward medical occurrence that, at any dose, results in death, is life threatening, requires hospitalization or prolongation of existing hospitalization, results in disability/incapacity, or results in a congenital anomaly/birth defect.

Safety population included all participants who received at least a single dose of study drug.

An AE is defined as any untoward medical occurrence in a participant or clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered to be related to the medicinal product. The AEs of special interests included gingival bleeding, tooth abscess, acarodermatitis, ear infection, gastroenteritis, herpes zoster ophthalmic, lice infestation, nasopharyngitis, oral fungal infection, oral herpes, pharyngitis, rhinitis, sinusitis, tonsillitis, tracheitis, tracheobronchitis, urinary tract infection, menorrhagia, asthma, epistaxis, and hematoma.

Safety population included all participants who received at least a single dose of study drug.

An AE is defined as any untoward medical occurrence in a participant or clinical investigation participant, temporally associated with the use of a medicinal product, whether or not considered to be related to the medicinal product. Relatedness of any AEs was reported as possibly related, probably related, or remotely related to TCZ.

Safety population included all participants who received at least a single dose of study drug.

Participants received TCZ for Week 104 or when TCZ was commercially available for pcJIA participants, whichever comes first in France. The mean TCZ exposure (time from first to last administration) was reported.

Safety population included all participants who received at least a single dose of study drug.

The participants were followed-up from Day 1 to last visit date (approximately 2 years). Mean time for which participants were followed up in the study was reported.

Safety population included all participants who received at least a single dose of study drug.

Number of participants with AEs leading to TCZ modification, AEs leading to death, anaphylaxis or serious hypersensitivity, and deaths were reported.

Safety population included all participants who received at least a single dose of study drug.

Clinically significant abnormal parameters included eosinophil count, alanine aminotransferase, total bilirubin, and protein and blood in urine. Number of participants with these abnormal lab parameters was reported.

Safety population included all participants who received at least a single dose of study drug.

Participants with abnormal physical examinations of ear, nose and throat (asthma); extremities (synovitis, sequelae with flexion of the 5th right proximal interphalangeal joint, hallux valgus, deviations of metatarsophalangeal joints, and callus under metatarsal head); lung (mild bronchospasm); skin (vitiligo and hematoma, fatty subcutaneous infiltration on the neck, cutaneous eruption, and scalp pediculosis); and musculoskeletal system (discomfort in right hip) were reported.

Safety population included all participants who received at least a single dose of study drug.

The Juvenile Idiopathic Arthritis (JIA) American College of Rheumatology (ACR) is comprised of six components: Maximum number of joints with active arthritis; Number of joints with limitation of movement; Erythrocyte Sedimentation Rate (ESR) and/or C-reactive Protein (CRP); Childhood Health Assessment Questionnaire-Disease Index (CHAQ-DI) graded on 4-point scales [0 = without any difficulty and 3 = unable to do] of 30 items grouped into 8 domains of physical function; Physician's global assessment of disease activity and Participant's global assessment of overall well-being (both assessed on a 0 to 100 mm Visual Analogue Scale [VAS], where score 0 = inactive arthritis and 100 = very active arthritis). A JIA ACR50/70 response is defined as improvement in at least three of the six core components by at least 50 percent (%), or 70%, respectively and no more than one of the remaining core components worsening by more than 30%.

The ITT population included all participants who had at least one efficacy assessment. Number (n) = number of participants analyzed for the given parameter at the specified visit.

Inactive disease was defined as: 1) No joints with active arthritis (no swollen, painful and lack of motion joints), 2) No fever, rash, serositis, splenomegaly, or generalized lymphadenopathy attributable to JIA, 3) No active uveitis, 4) ESR and/or CRP within normal range, and 5) No disease activity according to Physician's global assessment of disease activity (<= 10 millimeters [mm] on a VAS). The participant's treating physician provided a rating of the participant's arthritis disease activity on a 0 to 100 mm horizontal scale where score 0 represented 'arthritis inactive' (i.e., symptom-free and no arthritis symptoms) and score 100 represented 'arthritis very active'.

The ITT population included all participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

Clinical remission was defined as inactive disease observed for at least 6 continuous months. Clinical remission was defined as per medication uptake as: Level 1 (clinical remission on medication), Level 2 (clinical remission off oral corticosteroid medication [still on TCZ]), Level 3 (clinical remission off both oral corticosteroid and methotrexate medication [still on TCZ]), and Level 4 (clinical remission off all anti-inflammatory medications [still on TCZ]). Number of participants at each clinical remission level was reported.

The ITT population included all participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

The CHAQ-DI included questions on dressing and grooming, arising, eating, walking, hygiene, reach, grip, and activities. The disability index (DI) of the original CHAQ was graded on 4-point categorical scales of 30 items grouped into 8 domains of physical function. The highest scoring item in each domain determined the score for that domain. The score for the disability index was the mean of domain scores ranging from 0 to 3 (0 = without any difficulty and 3 = unable to do) with higher scores meaning higher disability. Minimally important improvement in CHAQ-DI was defined as a change from baseline of WA19977 core study (Day 1/Visit 1) >=0.13 at each visit.

The ITT population included all the participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

The most frequent symptom reported by most participants was a limitation of motion (LOM) of joints and it was determined by physical examination. The mean joints with limitation of motion were reported.

The ITT population included all the participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

The active range of motion joints was counted by physical examination and mean joints was reported.

The ITT population included all the participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

The swollen joints was counted by physical examination and mean swollen joints were reported.

The ITT population included all the participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

The painful joints were counted by physical examination and mean painful joints was reported.

The ITT population included all the participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

The Physician's global assessment of disease activity was recorded on a 0 to 100 mm horizontal VAS where score 0 represented 'arthritis inactive' (i.e., symptom-free and no arthritis symptoms) and score 100 represented 'arthritis very active' (higher score indicate worsening of disease).

The ITT population included all the participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

Parent/patient global assessment of disease activity was performed using 0 to 100 mm VAS, and higher the score of VAS, worse the disease status (0= absence of activity or sign or symptom; 100= maximal activity or signs or symptoms). No disease activity was defined as VAS <=10 mm.

The ITT population included all the participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.

Participants or parents rated participant's pain by placing a horizontal line on a VAS of 0 (no pain) - 100 mm (unbearable pain). To describe the pain, a cut-off at 10 mm was used, and VAS <10 mm was defined as no pain.

The ITT population included all the participants who had at least one efficacy assessment. n = number of participants analyzed for the given parameter at the specified visit.