Haemoglobin changes and disease activity in Japanese patients with rheumatoid arthritis treated with sarilumab

ObjectiveAnaemia is a frequent extra-articular manifestation in rheumatoid arthritis (RA); haemoglobin level changes are associated with changes in disease activity. This post-hoc analysis assessed potential relationships between haemoglobin and disease activity in Japanese patients with RA, enrolled in the KAKEHASI study (NCT02293902).MethodsIn this study, adult patients with moderate-to-severe active RA, who had an inadequate response to methotrexate, were randomised to subcutaneous sarilumab 150 mg every 2 weeks (q2w) or 200 mg q2w or placebo for 24 weeks. Post-hoc analyses were conducted on changes in haemoglobin and proportion of anaemic patients, using a mixed-effects model for repeated measures assuming an unstructured covariance. Relationships between haemoglobin and efficacy measures were explored.ResultsAt baseline, nearly half of patients had anaemia, defined by World Health Organization criteria (haemoglobin <12 g/dL, female; or <13 g/dL, male). At Week 24, the least squares mean change in haemoglobin levels was greater in sarilumab groups than for placebo (150 mg: 1.23 g/dL, 200 mg: 1.19 g/dL, placebo: 0.17 g/dL; p=0.0002 for both doses vs. placebo). By Week 24, the proportion of patients with anaemia was 17.8%, 22.9%, and 30.1% for sarilumab 150 mg, 200 mg, and placebo, respectively.ConclusionIn Japanese patients with RA, both doses of sarilumab were associated with greater improvement in haemoglobin levels and reduction in proportion of patients with anaemia, compared with placebo. Sarilumab may be a suitable treatment for patients with RA and anaemia.