WEDNESDAY, Oct. 5 (HealthDay News) -- A new oral drug for relapsing forms of multiple sclerosis appears to reduce relapse rates and disability progression, according to the results of a so-called phase 3 trial.

The experimental drug, teriflunomide, is one of the few oral drugs that treat this type of MS and may, if approved, be a good choice for many MS patients, researchers said.

"Basically, these are very good results because not only was the drug effective, but it was also very safe," said lead researcher Dr. Paul O'Connor, director of the Multiple Sclerosis Clinic and MS Research at the University of Toronto in Canada.

The report was published in the Oct. 6 issue of the New England Journal of Medicine. A phase 3 trial is done once it is known that a drug is safe and is usually the last step before U.S. Food and Drug Administration approval is sought.

For the study, O'Connor's team randomly assigned 1,088 patients, ages 18 to 55, with relapsing/remitting multiple sclerosis to 7 or 14 milligrams of teriflunomide or a placebo once a day for more than two years.

Over that time, patients taking teriflunomide saw a 31 percent reduction in relapses with either dose of the drug, compared with patients taking the placebo.

More than 27 percent of those receiving a placebo showed disease progression, compared with 21.7 percent of those taking 7 milligrams of teriflunomide and 20.2 percent of those taking the 14 milligram dose, the researchers found. MRI scans confirmed the differences.

The drug was basically well tolerated, but side effects -- such as diarrhea, nausea, and hair thinning -- were more common among teriflunomide patients than placebo patients. There were also higher levels of an enzyme that can indicate liver damage in those on the drug, the researchers noted.

The study was funded by Sanofi-Aventis, the maker of teriflunomide. When or if the drug will be approved for sale is not known, O'Connor said.

Most of the current MS drugs are injectables, and Timothy Coetzee, a spokesman for the National Multiple Sclerosis Society, said that "having an oral treatment option is always a good thing."

"What I hear from people with MS is that they would prefer an oral treatment," Coetzee said.

However, treatment choice is also influenced by how long a drug has been on the market. Some doctors and patients may prefer using an older, proven treatment rather than a new drug that has not had a lot of real-world testing, he said.

Another oral drug for multiple sclerosis, fingolimod (Gilenya), approved by the FDA in 2010, appears to be more effective than teriflunomide, but it has more serious side effects, Coetzee said.

Dr. Kottil W. Rammohan, a professor of neurology at the University of Miami Miller School of Medicine, said he thinks the compliance rate will be better with an oral drug than with shots.

"This drug (teriflunomide) is as effective as the shots," he said.

Another oral multiple sclerosis drug, BG-12, is also in phase 3 trials, with results similar to those for teriflunomide and it is also well tolerated, Rammohan said.

"The landscape of MS treatment is becoming rosier by the minute," he added.

Dr. Moses Rodriguez, professor of neurology and immunology at the Mayo Clinic in Rochester, Minn., said teriflunomide appears to be relatively safe in contrast to other drugs for MS.

"I am impressed that there were not many serious infections, which makes this an attractive drug for MS patients," Rodriguez said.

But until the long-term consequences of taking teriflunomide are known, Rodriguez said he suspects that most doctors will stick with interferons for the first line of therapy. If those fail, he said, teriflunomide would be used before the newly approved injectable drug Tysabri, which has been linked with a serious brain infection.

Multiple sclerosis is a disease of the nervous system that affects the brain and spinal cord. It damages the myelin sheath, which surrounds and protects nerve cells. MS symptoms can include muscle weakness; balance and coordination problems; and thinking and memory problems, according to the U.S. National Institutes of Health.

More information

For more on multiple sclerosis, visit the National Multiple Sclerosis Society.