Key clinical point: Subcutaneous methotrexate is safe for routine use in rheumatoid arthritis patients, with significantly lower adverse event rates, compared with biologics and disease-modifying antirheumatic drug (DMARD) combination therapy.

Major finding: Rheumatoid arthritis patients treated with subcutaneous methotrexate had higher drug continuation rates, compared with those treated with oral methotrexate (67% vs. 54%; P < 0.0001). Users of subcutaneous methotrexate also experienced significantly fewer adverse events, compared with patients treated with conventional DMARD combination therapy (two or more of methotrexate, leflunomide, hydroxychloroquine, and/or sulfasalazine), biologic monotherapy, and biologic combination therapy (a biologic and one or more conventional DMARDs).

Study details: The data come from 8,394 adults with rheumatoid arthritis.

Disclosures: The study received no outside funding. The researchers had no financial conflicts to disclose.

Commentary

“The subcutaneous formulation of methotrexate (MTX) is usually used in patients with RA who have gastrointestinal side effects with the oral formulation, a side effect that limits use of higher oral doses in patients with RA despite better clinical outcomes. It has also been suggested that subcutaneous MTX is more effective than the oral formulation, perhaps because of greater bioavailability.

This study looks at the safety and efficacy of subcutaneous MTX in routine clinical practice in rheumatology practices in England. 8,394 patients with RA were allocated into treatment groups and side effects and outcomes compares; patients using subcutaneous MTX had similar rates of neutropenia and slightly higher rates of transaminitis than those taking oral MTX. Fewer people discontinued the subcutaneous form or had gastrointestinal side effects. The study is observational and retrospective and thus efficacy cannot be extrapolated; however, fewer patients taking subcutaneous MTX stopped it due to inefficacy compared to oral. Given its success in the population studied, subcutaneous MTX likely should be used more frequently among patients with RA in order to maximize the benefits of MTX and minimize associated side effects.”

Arundathi Jayatilleke, MD

Lewis Katz School of Medicine, Temple University