Editor’s note: This article is part of WRAL Local Tech Wire’s efforts to highlight research at universities across the Carolinas and Georgia.

CHAPEL HILL – For patients with rheumatoid arthritis, combining one well-known, lower-cost synthetic drug with one of six biologic medications often works best to reduce joint swelling or tenderness, according to a new report by researchers at the RTI International-University of North Carolina at Chapel Hill Evidence-based Practice Center, which is sponsored by the federal Agency for Healthcare Research and Quality (AHRQ).

An article based on the report, "Comparative Effectiveness of Drug Therapy for Rheumatoid Arthritis and Psoriatic Arthritis in Adults," was posted on line in the Annals of Internal Medicine.

Researchers reviewed published evidence to compare the benefits and harms of three classes of medications: synthetic disease-modifying antirheumatic drugs (DMARDs), biologic DMARDs and corticosteroids.

The report concluded that combining methotrexate, a synthetic DMARD, with one of the biologic DMARDs works better than using methotrexate or a biologic DMARD alone.

The report also found that methotrexate works as effectively as the biologic DMARDs adalimumab and etanercept for patients who have early rheumatoid arthritis.

Dr. Katrina Donahue, an assistant professor of family medicine in UNC’s School of Medicine and a fellow in the Cecil G. Sheps Center for Health Services Research at UNC, is lead author of the report. She said not enough evidence exists to determine whether combining two biologic DMARDs is more effective than using one biologic DMARD.

More long-term research is needed on rheumatoid arthritis medications, including how the outcomes of these drugs vary among patients with different health conditions and demographic characteristics. More comparative studies on various combinations of drugs are critical. Also important is investigating whether taking the medications earlier (especially biologic DMARDs) is better for long-term outcomes, Donahue said.

Dr. Carolyn M. Clancy, AHRQ director, added: “This report establishes a clear, unbiased summary of what is known about current treatments. It also identifies areas where more research is needed.”

Co-authors of the report, from UNC, are Dr. Gerald Gartlehner, Dr. Daniel Jonas, Patricia Thieda, Richard A. Hansen, Dr. Beth Jonas, Laura Morgan and Stacey C. Williams, and from RTI, Linda Lux and Kathleen Lohr.