MTX Monotherapy Matches Etanercept Combo in Early Inflammatory Arthritis

Nam JL, Villeneuve E, Hensor EM, et al., A randomised controlled trial of etanercept and methotrexate to induce remission in early inflammatory arthritis: the EMPIRE trial.Ann Rheum Dis. (2014) DOI: 10.1136/annrheumdis-2013-204882. [Epub ahead of print 13 March 2014]

The first head-to head randomized placebo-controlled trial comparing etanercept (Enbrel) plus methotrexate (MTX) combo therapy with MTX monotherapy for early inflammatory arthritis found equal numbers of patients with no tender or swollen joints after a year.

However, the combination worked more quickly. While neither treatment was better at inducing remission by 78 weeks, within as little as two weeks after a single injection many more patients on ETN-MTX  (38.5% vs. 9.2%) were achieving improved clinical responses -- reduced disease activity in 28 joints and C-reactive protein (DAS28-CRP) scores under 2.6 -- than were those on MTX alone (385.% vs 9.2%).

None of the 110 patients in the multi-center EMPIRE trial had ever taken disease modifying anti-rheumatic drugs (DMARDs). The majority of subjects were women in their late 40s with early clinical synovitis (one or more tender and swollen joints seen within 3 months of diagnosis).

They also tested positive for rheumatoid factor (RF), anti-citrullinated protein antibodies (ACPAs), or the same disease-related genes (shared epitope).

Investigators randomized equal numbers to weekly subcutaneous injections of 50 mg ETN or of a visually similar placebo, plus doses of MTX increasing from 10 mg to 25 mg, depending on response.

If patients had no tender of swollen joints (NTSJ) at 26 weeks, the injections were stopped early. Those with NTSJ 12 weeks after the injections were stopped were weaned off MTX.

After 52 weeks, there were no statistical differences between the combo an monotherapy groups in the primary endpoint of NTSJ  (32.5% and 28.1%, respectively) or in DAS28-CRP below 2.6 (68.8% and 62.5%, respectively).

At 78 weeks, there were no significant between-group differences in the secondary outcomes: NTSJ, remission by 2010 ACR/EULAR criteria, improvement in patient-reported outcomes, and radiographic non-progression, as well as in the number of adverse events (mostly infections).

About a third of the patients required a switch in DMARD therapy (including biologics) during the trial. By its conclusion, 3.6% had achieved drug-free remission.