Aubagio (teriflunomide), a once-daily tablet for adults with relapsing forms of MS (multiple sclerosis), has been approved by the US Food and Drug Administration (FDA).

According to experts, the Multiple Sclerosis prescribing market is worth $12 billion annually. If Aubagio becomes popular, it has the potential to become a major earner for its makers, Sanofi-Aventis. However, it is entering a highly-competitive market with very effective existing medications. Novartis’ Gilenya and Tysabri from Elan Corp are said to be more effective than teriflunomide.

Director of the Division of Neurology Products in the FDA’s Center for Drug Evaluation and Research, Russell Katz, M.D., director of the Division of Neurology Products in the FDA’s Center for Drug Evaluation and Research, said:

“In a clinical trial, the relapse rate for patients using Aubagio was about 30 percent lower than the rate for those taking a placebo. Multiple sclerosis can impair movement, sensation, and thinking, so it is important to have a variety of treatment options available to patients.”

Multiple sclerosis is a long-term autoimmune, inflammatory disease of the central nervous system. Communication between the brain and other parts of the body are disrupted. Multiple Sclerosis is one of the most common causes of neurological disability in young adults. Twice as many females live with MS than males.

People with MS have episodes of relapses (worsening function), followed by remissions (recovery). Eventually, remission periods may be incomplete as the disease progresses. Aubagio has been approved for the initial phases of the disease.

According to clinical trial results, the following side effects among people taking Aubagio were reported: hair loss, nausea, abnormal liver test results, and diarrhea.

Aubagio contains a Boxed Warning explaining to doctors and their patients that there is a risk of liver problems, which may sometimes be fatal, as well as birth defects. Doctors should carry out blood tests beforehand to make sure liver function is normal. During treatment with Aubagio, liver functions tests should be performed periodically.

The Boxed Warning also alerts prescribers and their patients about some animal studies which linked the drug with a higher risk of fetal harm. That is why Aubagio is labeled as a Pregnancy Category X drug, meaning that female patients of childbearing age should have negative pregnancy test results (and use effective birth control therapy) before being considered for Aubagio treatment.

When Aubagio is dispensed, it will be accompanied with a patient Medication Guide that provides important instructions on its use and drug safety information.