WASHINGTON (Reuters) - It seems to make little difference which drug a patient uses to treat rheumatoid arthritis, although mixing different types of drugs in a cocktail approach works better than using a single treatment, U.S. researchers said on Monday.
A team at the Agency for Healthcare Research and Quality looked at 11 different drugs used to treat rheumatoid arthritis, an incurable, joint-destroying condition, and found no single medication or combination stood out.
“Although combination therapy is more effective for patients whose monotherapy fails, the evidence is insufficient to draw firm conclusions about whether one combination or treatment strategy is better than another or is the best treatment for early rheumatoid arthritis,” the team, led by Dr. Katrina Donahue of the University of North Carolina, reported in the Annals of Internal Medicine.
They searched clinical trials that enrolled at least 100 people between 1980 and 2007. A variety of drugs are used to relieve the symptoms of the disease, marked by inflammation, destruction of the joint and weakness of the surrounding tissues.
About 2 million Americans and 400,000 Britons have rheumatoid arthritis, an autoimmune disease caused when the body confuses healthy tissue for foreign substances and attacks itself.
Some drugs used to treat it reduce inflammation directly while others tone down immune system response — leaving patients vulnerable to infections and cancer.
“Experts do not agree about the comparative benefits of different combination therapies. Many questions remain about the risks of these agents across a spectrum of adverse events from relatively minor side effects to severe and possible life threatening problems,” the researchers wrote.
The researchers looked in detail at 101 studies — half of them paid for by drug companies, 20 percent by government, 10 percent with mixed funding and another 20 percent in which it was impossible to say who funded the work.
The therapies included corticosteroids, synthetic disease modifying anti-rheumatic drugs, or DMARDs, such as hydroxychloroquine, leflunomide, methotrexate and sulfasalazine.
They also looked at biological DMARDs such as abatacept, made by Bristol-Myers Squibb Co. under the brand name Orencia; adalimumab, sold by Abbott Laboratories as Humira; anakinra or Kineret, made by Amgen Inc; etanercept, sold by Amgen under the brand name Enbrel; infliximab, sold by Johnson & Johnson under the Remicade brand name; and rituximab, marketed by Genentech Inc and Biogen Idec Inc under the Rituxan and MabThera brand names.
The drugs generated sales of nearly $10 billion in 2006.
“Rheumatoid arthritis is a painful, degenerative disease that affects people of all ages and can profoundly impact quality of life,” AHRQ Director Dr. Carolyn Clancy said in a statement.
“This report establishes a clear, unbiased summary of what is known about current treatments. It also identifies areas where more research is needed.”
Editing by Will Dunham and Jackie Frank