Tocilizumab Increases Body Weight and Serum Adipokine Levels in Patients with Rheumatoid Arthritis Independently of Their Treatment Response: a Retrospective Cohort Study.

Background: Causes of weight change after tocilizumab treatment are unclear. We aimed to investigate the effects of tocilizumab treatment on body weight and serum adipokine levels in patients with rheumatoid arthritis (RA).
Methods: In this retrospective cohort study, we evaluated weight changes in patients with RA who received methotrexate (Cohort I) or tocilizumab with methotrexate (Cohorts II and III) for 24 weeks. Adipokine concentrations at baseline and 24 weeks were analyzed in Cohorts I and III. Cohorts I and II received tocilizumab therapy for an additional 48 weeks, during which weight changes were monitored (24-72 weeks).
Results: No significant weight change occurred after 24 weeks of methotrexate treatment (mean difference, -0.2 kg; P = 0.630), but was observed after 24 weeks of tocilizumab treatment (mean difference, +0.9 kg; P = 0.010). Weight changed regardless of the treatment response in both treatment groups. The leptin-adiponectin ratio ( P = 0.015) and levels of adiponectin ( P < 0.001), leptin ( P < 0.001), and resistin ( P = 0.003) increased significantly after 24 weeks of tocilizumab, but not methotrexate treatment. After 24, 48 and 72 weeks of tocilizumab treatment in Cohort II, mean (95% confidence interval [CI]) weight changes from baseline were +0.7 (0.0-1.4), +1.2 (0.4-2.0) and +1.1 (0.2-2.0) kg, respectively, and mean (95% CI) percent weight changes from baseline were +1.3% (0.1%-2.6%), +2.2% (0.7%-3.6%), and +2.0% (0.4%-3.7%) at 24, 48, and 72 weeks, respectively.
Conclusion: Weight and the leptin-adiponectin ratio increased after tocilizumab treatment. Given that cardiovascular (CV) risk factors may deteriorate in patients with RA who receive tocilizumab, further studies are required to determine the effects of weight gain on CV outcomes in these patients.
Competing Interests: IA Choi received a research grant from Chungbuk National University Hospital in 2018. She received a research grant from LG Chem and AbbVie Korea, which is not relevant to this study. EY Lee received the grants from the Ministry of Science, ICT and Future planning (NRF-2019M3A9A8065574). EB Lee has received research grants from Pfizer Korea, and has been a consultant for Pfizer. YW Song received a research grant from JW Pharmaceuticals during the clinical trials (NCT01211834 and NCT01256736). The use of clinical data and serum samples in this study were supported by JW Pharmaceuticals. The present study received grants from the Ministry of Science, ICT and Future planning (NRF-2015M3A9B6052011, 2019M3A9A8065574) and a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (HI14C1277).
(© 2020 The Korean Academy of Medical Sciences.)