HCPs will perform injection of SC tocilizumab to participants with RA using the AI-1000 G2 device. Because enrolled HCPs are to be professionally qualified to deliver SC injections, no administration training will be provided. Visit 1 (Day 0) will be performed by the study nurse. Visits 2 and 3 (Days 14 and 28) will be conducted by the HCP for use/performance evaluation.

Participants will receive three doses of SC tocilizumab using the AI-1000 G2 device at Visits 1, 2, and 3 (Days 0, 14, and 28). The dose will remain at 162 milligrams (mg) unless changes are required per protocol for safety or efficacy reasons.

Injection pain was assessed on a continuous 100-millimeter (mm) VAS, where 0 mm represents "no pain" and 100 mm represents "unbearable pain". The mean VAS response at each assessment timepoint was reported among participants with RA.

Injection pain was assessed on a categorical 6-point Likert scale, ranging from "no pain" to "severe and intolerable". The percentage of participants was reported by response at each assessment timepoint among participants with RA.

Device satisfaction was assessed using twelve questions on a categorical 5-point Likert scale, ranging from "strongly agree" to "strongly disagree". Question (Q) 1 (felt the autoinjection was easy to use), Q2 (felt comfortable while using the autoinjector), Q3 (felt the autoinjector was easy to hold), Q4 (able to tell when injection had completed), Q5 (felt he/she can inject properly with the autoinjector), Q6 (felt he/she had control over the injection process), Q7 (felt confident that he/she injected successfully), Q8 (felt it is easy to dispose of the autoinjector), Q9 (autoinjector would help to manage his/her injection schedule), Q10 (liked the look/feel of the autoinjector), Q11 (would recommend the autoinjector to someone else who needed to inject), Q12 (would continue having injections with the autoinjector). The percentage of participants was reported by response at each assessment among participants with RA, CGs, and HCPs.

Sixty-eight joints were assessed for tenderness among participants with RA. The number of tender joints at Baseline was reported.

Sixty-six joints were assessed for swelling among participants with RA. The number of swollen joints at Baseline was reported.

Ability to perform daily living activities was assessed across eight component sets including dressing/grooming, arising, eating, walking, hygiene, reach, grip, and common activities. Twenty questions were scored on a 4-point Likert scale from 0 meaning "without any difficulty" to 3 meaning "unable to do". The overall score was computed as the sum of domain scores divided by the number of domains answered. Therefore, the score range for HAQ-DI was the same as that of the individual questions, that is, from 0 to 3, where 0 indicates "least difficulty" and 3 indicates "extreme difficulty". The mean change from baseline in HAQ-DI at each assessment was reported among participants with RA.

Participants with RA performed self-injection of 162 mg SC tocilizumab with the AI-1000 G2 device. Visit 1 (Day 0) was conducted for administration training, while Visits 2 and 3 (Days 14 and 28) were conducted for use/performance evaluation.

CGs performed injection of 162 mg SC tocilizumab to participants with RA using the AI-1000 G2 device. Visit 1 (Day 0) was conducted for administration training, while Visits 2 and 3 (Days 14 and 28) were conducted for use/performance evaluation.

HCPs performed injection of 162 mg SC tocilizumab to participants with RA using the AI-1000 G2 device. Because enrolled HCPs were to be professionally qualified to deliver SC injections, no administration training was provided. Visit 1 (Day 0) was performed by the study nurse. Visits 2 and 3 (Days 14 and 28) were conducted by the HCP for use/performance evaluation.

Total of all reporting groups

Safety-critical tasks included those tasks where errors would have a reasonably foreseeable potential for clinical impact/harm, potentially resulting in direct physical injury to the user and/or conditions that require medical intervention. Safety-critical tasks included the following: release activation button; check the expiry date; inspect device prior to use; and inspect medication prior to use. Essential tasks included those essential to the execution of the injection. Essential tasks included the following: open the carton, remove the device and associated documents; remove cap; start an injection by depressing the needle-shield at the injection site and pressing the activation button; and hold the autoinjector until the complete dose has been delivered. The percentage of participants who successfully performed safety-critical and essential tasks during the second unassisted use (Day 28) was reported.

Safety Population; only those who performed the administration task(s) on Day 28 were included because the endpoint was not applicable to non-injecting participants.

Ancillary tasks included those tasks where the potential harm resulting from use error would be minor in severity, or the resultant harms were estimated to occur at sufficiently low levels. Ancillary tasks included the following: wash hands; clean the injection site with alcohol swab; wait for the alcohol to dry; dispose of the autoinjector cap; inspect full dose delivered after use; dispose of the autoinjector; and treatment of injection site after injection. The percentage of participants who succesffully performed ancillary tasks during the first (Day 14) and second unassisted use (Day 28) was reported.

Safety Population; only those who performed the administration task(s) were included because the endpoint was not applicable to non-injecting participants. Here, "n" refers to number evaluable for the specified assessment, respectively.

Injection pain was assessed on a continuous 100-millimeter (mm) VAS, where 0 mm represents "no pain" and 100 mm represents "unbearable pain". The mean VAS response at each assessment timepoint was reported among participants with RA.

Safety Population; only participants with RA were included because the endpoint was not applicable to CGs and HCPs. Here, "n" refers to number evaluable for the specified assessment, respectively.

Injection pain was assessed on a categorical 6-point Likert scale, ranging from "no pain" to "severe and intolerable". The percentage of participants was reported by response at each assessment timepoint among participants with RA.

Safety Population; only participants with RA were included because the endpoint was not applicable to CGs and HCPs. Here, "n" refers to number evaluable for the specified assessment, respectively.

Device satisfaction was assessed using twelve questions on a categorical 5-point Likert scale, ranging from "strongly agree" to "strongly disagree". Question (Q) 1 (felt the autoinjection was easy to use), Q2 (felt comfortable while using the autoinjector), Q3 (felt the autoinjector was easy to hold), Q4 (able to tell when injection had completed), Q5 (felt he/she can inject properly with the autoinjector), Q6 (felt he/she had control over the injection process), Q7 (felt confident that he/she injected successfully), Q8 (felt it is easy to dispose of the autoinjector), Q9 (autoinjector would help to manage his/her injection schedule), Q10 (liked the look/feel of the autoinjector), Q11 (would recommend the autoinjector to someone else who needed to inject), Q12 (would continue having injections with the autoinjector). The percentage of participants was reported by response at each assessment among participants with RA, CGs, and HCPs.

Safety Population. Here, "n" refers to number evaluable for the specified assessment, respectively.

Sixty-eight joints were assessed for tenderness among participants with RA. The number of tender joints at Baseline was reported.

Safety Population; only participants with RA were included because the endpoint was not applicable to CGs and HCPs.

Sixty-six joints were assessed for swelling among participants with RA. The number of swollen joints at Baseline was reported.

Safety Population; only participants with RA were included because the endpoint was not applicable to CGs and HCPs.

Ability to perform daily living activities was assessed across eight component sets including dressing/grooming, arising, eating, walking, hygiene, reach, grip, and common activities. Twenty questions were scored on a 4-point Likert scale from 0 meaning "without any difficulty" to 3 meaning "unable to do". The overall score was computed as the sum of domain scores divided by the number of domains answered. Therefore, the score range for HAQ-DI was the same as that of the individual questions, that is, from 0 to 3, where 0 indicates "least difficulty" and 3 indicates "extreme difficulty". The mean change from baseline in HAQ-DI at each assessment was reported among participants with RA.

Safety Population; only participants with RA were included because the endpoint was not applicable to CGs and HCPs. Here, "n" refers to number evaluable for the specified assessment, respectively.

CGs performed injection of 162 mg SC tocilizumab to participants with RA using the AI-1000 G2 device. Visit 1 (Day 0) was conducted for administration training, while Visits 2 and 3 (Days 14 and 28) were conducted for use/performance evaluation.

HCPs performed injection of 162 mg SC tocilizumab to participants with RA using the AI-1000 G2 device. Because enrolled HCPs were to be professionally qualified to deliver SC injections, no administration training was provided. Visit 1 (Day 0) was performed by the study nurse. Visits 2 and 3 (Days 14 and 28) were conducted by the HCP for use/performance evaluation.