Teriflunomide joins the growing list of cell cycle inhibiting drugs in the pipeline for multiple sclerosis (MS) treatment. The drug inhibits replication and function of activated T cells, but has no effect on resting T cells.
The 1088 participants in the TEMSO trial had mild disability with an Expanded Disability Status Scale (EDSS) score of 5 or less, with at least one relapse over the previous year or two relapses over the previous two years. They were randomized evenly to placebo or teriflunomide at 7 milligrams or 14 milligrams once a day.
At the end of the 108week trial, the annualized relapse rate was equivalent in the two active treatment arms, 0.37, compared with 0.54 for the placebo arm, a relative risk reduction of 31%. The risk of disability progression was also reduced by treatment. The proportion of participants with 12week confirmed disability progression was 27% for placebo, 22% for lowdose and 20% for highdose teriflunomide.
The rate of adverse events was the same among all groups, as was the rate for serious adverse events, and there were no deaths.