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

OBJECTIVES: Anaemia 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). METHODS: In 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. RESULTS: At 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. CONCLUSIONS: In 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.