To evaluate the impact of treatment with disease-modifying antirheumatic drugs (DMARDs), including IL-6 receptor inhibitor tocilizumab (TCZ), on anaemia markers in patients with rheumatoid arthritis.
Using the Centricity Electronic Medical Records from USA, patients with rheumatoid arthritis diagnosed between January 2000 and April 2016, who initiated TCZ (n = 3732); tofacitinib (TOFA, n = 3126); other biologic DMARD (obDMARD, n = 55,964); or other non-biologic DMARD (onbDMARD, n = 91,236) were identified. Changes in haemoglobin (Hb) and haematocrit (Hct) over 2 years of treatment initiation were evaluated, adjusting and balancing for confounders.
Mean (95% CI) adjusted increase in Hb and Hct levels at 24 months in TCZ group were 0.23g/dL (0.14, 0.42) and 0.96% (0.41, 1.52) respectively. Among patients with anaemia in the TCZ group, Hb and Hct increased significantly by 0.72g/dL and 2.06%, respectively. Patients in the TCZ group were 86% (95% CI of OR: 1.43, 2.00) more likely to increase Hb ≥ 1g/dL compared to the other groups combined. No clinically significant changes in Hb were observed in the other groups. The obDMARD group demonstrated lower Hct increase than TCZ group, while no significant changes were observed in the remaining groups. Compared to those who initiated TCZ therapy after 1 year of diagnosis of rheumatoid arthritis, those who initiated earlier were 95% (OR = 1.95; 95% CI: 1.19, 3.21; p < 0.001) more likely to increase Hb within 6 months.
This real-world study suggests significant increase in Hb and Hct levels after TCZ therapy in anaemic and non-anaemic patients with rheumatoid arthritis, compared with other biologic and non-biologic DMARDs.