Effectiveness and tolerability of oral vs subcutaneous methotrexate in patients with rheumatoid arthritis

Objectives The aim of this study was to compare the effectiveness and tolerability between oral MTX and s.c. MTX in a large group of RA patients in a real-life setting. Methods In this retrospective cohort study, adult patients with clinical diagnosis of RA who started MTX treatment (monotherapy or combined with HCQ) started with either oral or s.c. MTX. The primary outcome was superiority testing of between group difference in change in DAS28CRP between baseline and 3-6 months, and subsequent non-inferiority (non-inferiority margin 0.6) testing analyses in case of non-superiority. Secondary outcomes included MTX dose, side effects, laboratory abnormalities and use of comedication. Results Six hundred and forty RA patients were included: 259 started with oral MTX and 381 with s.c. MTX. There was no significant difference in Delta DAS28CRP [after adjusting for confounding, 0.13 (95% CI: -0.14, 0.40)], and oral MTX strategy was non-inferior to s.c. The mean MTX dose was slightly lower for the oral strategy [18.0 (6.9) vs 19.9 (8.2), P = 0.002], which was accompanied by a lower cumulative incidence of adverse events (41% vs 52%, P = 0.005). No differences were seen in use of other comedication. Conclusion Starting with oral MTX in RA in a real-life setting is non-inferior to a s.c. MTX treatment with regard to disease activity control, at least when used in dosages up to 25 mg and on a background of HCQ co-treatment and a treat-to-target approach. In addition, tolerability was better. This supports the strategy of starting with oral MTX.