Background/Purpose: This is the first study assessing the effect of subcutaneous tocilizumab (TCZ-SC) and/or conventional synthetic DMARDs (csDMARDs) on work productivity and activity impairment (WPAI) in paid workers (PWs) and homeworkers (HWs) among Japanese patients with RA.

Methods: FIRST ACT-SC was a real-world, prospective, observational study (Jan 2014 to Sep 2015 at 82 centers). Biologic-naïve patients receiving ≥1 csDMARD, both PWs and HWs, and with moderate/high disease activity were enrolled and treated with TCZ-SC +/− csDMARDs or csDMARDs alone. The primary endpoint was the percentage change in overall work impairment (OWI; assessed using the WPAI questionnaire) from baseline to 52 weeks among PWs. Inverse probability of treatment weighting using propensity score was used to adjust for patient background to compare the 2 groups. Depending on the patientsf symptoms during the observation period, change of dose, change to another csDMARD, or addition of another csDMARD was allowed.

Results: In total, 377 and 347 patients were enrolled in the TCZ-SC +/− csDMARD and csDMARD-alone groups, respectively, of which 321 (mean}SD age, 57.7}14.0 years; female, 81.6%) and 307 (60.1}12.8 years; 85.7%) patients, respectively, were included in the modified intent-to-treat population. Of these, 233 (72.6%) and 224 (73.0%) patients, respectively, completed 52 weeks of follow-up. The primary and secondary endpoint results are summarized in the Table 1. Although disease activity (DAS28, SDAI, CDAI, etc.) and HAQ-DI improvements were better in the TCZ-SC group compared to the csDMARD group, the weighted percentage change in OWI from baseline was only −0.189 in the TCZ-SC group at 52 weeks, and there was no difference between the 2 groups (weighted treatment difference, 0.003; 95% CI, −0.062 to 0.068; P = 0.929). In contrast, the improvement in percentage activity impairment in HWs and the overall group was significantly better in the TCZ-SC group compared to the csDMARD group at week 52 (P = 0.005 and P = 0.003, respectively). TCZ-SC-treated HWs also showed significant improvement in overall quality of life (QOL), including EQ-5D, J-HAQ, and K6.

Conclusion: There was no significant difference in OWI between the 2 treatment groups. However, activity impairment, disease activity, and QOL in HWs and the overall group were significantly improved with TCZ-SC than with csDMARDs alone. Taken together, improvement in work productivity/activity impairment is determined by differences in TCZ-SC +/− csDMARDs and differences in PWs and HWs at baseline.

Role of the Study Sponsor: This study was supported by funding from Chugai Pharmaceutical Co., Ltd.

Acknowledgments: Medical writing assistance was provided by Mami Hirano, M.S., of Cactus Communications. Support for study management was provided by EPS Corporation.