Choice of the most appropriate biological disease-modifying anti-rheumatic drug for injection spacing: results from a multicentre observational study.

Objectives: To determine which biological disease-modifying anti-rheumatic drug (bDMARD) is most appropriate for spacing in patients with rheumatoid arthritis (RA) who have persistent stable symptoms.

Methods: In patients with sustained low disease activity (LDA) or better for ≥3 months who were treated with bDMARDs, the interval between bDMARD injections was extended 1.5 times, and treatment continuation rates at 104 weeks were calculated for each drug. Patients who discontinued therapy owing to adverse reactions and those who withdrew for reasons unrelated to the drugs were excluded. Whether patients could remain in LDA or better after injection spacing was investigated. The targeted drugs were an anti-tumour necrosis factor (TNF) inhibitor (golimumab [GOL]) and 2 non-TNF inhibitors (tocilizumab [TCZ] and abatacept [ABT]).

Results: The spacing evaluation included 57, 93, and 40 patients who received GOL subcutaneous injection (SC), TCZ (SC in 21 and drip intravenous injection [DIV] in 72), and ABT (SC in 12 and DIV in 22), respectively. At 104 weeks, the number of patients who discontinued therapy owing to adverse reactions did not significantly differ among the drugs. At 104 weeks, the treatment continuation rate was 0.71 for TCZ SC, 0.70 for GOL, 0.69 for TCZ DIV, 0.55 for ABT SC, and 0.50 for ABT DIV. The continuation rate for ABT was significantly lower than those for GOL and TCZ. No significant difference in continuation rates was observed between SC and DIV.

Conclusions: When the injection interval was extended, GOL and TCZ were superior to ABT in terms of continuation rate.