New Test Could Predict Piologic Drug Failure in Patients with Arthritis
A study conducted at the University of Manchester suggests it may be possible to predict which rheumatoid arthritis (RA) patients will fail to respond to the biologic drugs given to treat them. Biologics are given by injection and they work by stopping particular chemicals in the blood from activating the immune system and attacking the joints. They are usually given in combination with an anti-rheumatic, such as methotrexate, once the anti-rheumatic alone is no longer effective.
Although biologic drugs have dramatically improved the long-term health of people with severe RA, they stop working in one in five patients. This is sometimes as a result of anti-drug antibodies being formed – limiting their effectiveness.
The new study shows that testing at random times detect the antibodies and to measure the drug levels in the bloodstream is effective and makes it easier to use in a clinical setting. Dr Meghna Jani, from the University’s Centre for Musculoskeletal Research, said, “This test is easy to perform in a hospital setting, and could provide useful information on how to manage a patient whose rheumatoid arthritis is not being controlled by adalimumab.”
Research revealed that a total of 25% of patients on adalimumab developed antibodies, but none were found in the patients using etanercept. The researchers also found that higher doses of methotrexate, a drug often given together with the biologic treatment, was associated with lower levels of drug antibodies
Professor Anne Barton from The University of Manchester explained: “The next step will be to explore whether it is cost-effective to use these tests routinely in clinical practice, so that we can adjust treatments in those patients with low drug levels and anti-drug antibodies.”