Background: Remission and radiographic non-progression are goals in the treatment of early rheumatoid arthritis. The aim of the combination of methotrexate and etanercept in active early rheumatoid arthritis (COMET) trial is to compare remission and radiographic non-progression in patients treated with methotrexate monotherapy or with methotrexate plus etanercept.

Methods: 542 outpatients who were methotrexate-naive and had had early moderate-to-severe rheumatoid arthritis for 3-24 months were randomly assigned to receive either methotrexate alone titrated up from 7.5 mg a week to a maximum of 20 mg a week by week 8 or methotrexate (same titration) plus etanercept 50 mg a week. Coprimary endpoints at 52 weeks were remission measured with the disease activity score in 28 joints (DAS28) and radiographic non-progression measured with modified total Sharp score. Treatment was allocated with a computerised randomisation and enrolment system, which masked both participants and carers. Analysis was done by modified intention to treat with last observation carried forward for missing data. This study is registered with ClinicalTrials.gov, number NCT00195494).

Findings: 274 participants were randomly assigned to receive combined treatment and 268 methotrexate alone. 132 of 265 (50%, 95% CI 44-56%) patients who took combined treatment and were available for assessment achieved clinical remission compared with 73 of 263 (28%, 23-33%) taking methotrexate alone (effect difference 22.05%, 95%CI 13.96-30.15%, p<0.0001). 487 evaluable patients had severe disease (DAS28>5.1). 196 of 246 (80%, 75-85%) and 135 of 230 (59%, 53-65%), respectively, achieved radiographic non-progression (20.98%, 12.97-29.09%, p<0.0001). Serious adverse events were similar between groups.

Interpretation: Both clinical remission and radiographic non-progression are achievable goals in patients with early severe rheumatoid arthritis within 1 year of combined treatment with etanercept plus methotrexate.

Funding: Wyeth Research.