Findings published yesterday in the open access journal BMC Musculoskeletal Disorders show that the latest class of drugs used to treat rheumatoid arthritis (RA) are better than standard anti-inflammatories.
RA is a chronic, debilitating, inflammatory disease of the joints, which is usually treated with anti-inflammatory drugs such as methotrexate or steroids. However, the discovery that a protein from white blood cells, known as tumour necrosis factor alpha (TNFα), caused some of the symptoms of RA, led to the development of novel drugs which block TNFα. This group of drugs, known as anti-TNFα drugs (which include infliximab, etanercept and adalimumab), are now commonly used to treat RA.
However, there have been no “head-to-head” comparisons of the new anti-TNFα drugs in terms of safety or efficacy for the treatment of RA.
Alberto Alonso-Ruiz of the Cruces Hospital in Barakaldo, Vizcaya, Spain and colleagues at the Donostia Hospital and the University of the Basque Country, systematically searched for research on the use of anti-TNFα drugs in RA patients. They found thirteen clinical trials including over 7,000 patients. The researchers then analysed the trial results, systematically logging patient benefits and side effects for different doses of the three main anti-TNFα drugs.
Analysis of the combined results of all thirteen trials showed that anti-TNFα drugs, given at recommended doses, were better than the usual treatments, such as methotrexate, for treating RA. Patients who had previously seen little benefit from methotrexate alone showed a better response with combined anti-TNFα plus methotrexate therapy.
The team found that all three drugs were very similar in their benefits even at doses higher than those recommended by the drug manufacturer. This class of drugs, while very effective, does have a higher frequency of adverse side-effects. Patients on infliximab were most likely to drop out of a trial because of these side effects. In contrast, patients using etanercept had the lowest withdrawal rate. The researchers point out that this could be because this drug was not reported as being used at higher than recommended dosage in the trials.
“Anti-TNFα drugs such as infliximab, adalimumab and etanercept all appear to be effective in the treatment of RA” said Alonso-Ruiz. “Performing comparisons of new drugs is vital for measuring safety/efficacy relationships and monitoring adverse side-effects”.