Multiple sclerosis is a disease in which a person’s immune systems cells attack the myelin sheath that insulates nerves in the brain and spinal cord. Current treatments for multiple sclerosis are effective for only a proportion of people with the disease. Now,researchers from Stanford University report that a blood test might make it possible to identify which multiple sclerosis patients will respond to therapy.

According to this new research, published online in Nature Medicine, a simple blood test could indicate which multiple sclerosis patients are most likely to benefit from beta-interferon, an injectable drug which helps to minimize relapses of the disease. Using mice as an experimental model, the Stanford researchers identified two distinct chemical pathways through which the body’s inflammatory response triggers multiple sclerosis relapses. One of these pathways corresponded to people who responded to beta-interferon and the other pathway corresponded to those who did not. These findings were verified through analysis of blood samples from 26 human patients with multiple sclerosis.

Beta-interferon is an expensive drug, costing an estimated $25,000 (USD) per year. Approximately half of patients with multiple sclerosis respond to treatment with beta-interferon, which reduces the relapse rate by about one-third. However, beta-interferon is associated with side effects such as aches, fever and muscle pain. A blood test that could identify those most likely to respond to beta-interferon would spare non-responders from this side effect profile and the cost of the drug. Although a patent application for the multiple sclerosis blood test has been filed, it is likely to be at least a year or more before it might be submitted for marketing approval.

Source:

Nature Medicine. Published online 28 March 2010.