Teriflunomide and Its Mechanism of Action in Multiple Sclerosis

The document from 2014 reviews teriflunomide, a disease-modifying treatment for multiple sclerosis (MS), particularly its relapsing-remitting form. Teriflunomide works by inhibiting dihydro-orotate dehydrogenase, an enzyme necessary for the proliferation of activated T and B lymphocytes, thereby reducing their contribution to MS inflammation without causing clinical immune suppression. Preclinical and clinical trials, including data from over 2400 patients, have shown that teriflunomide reduces disease symptoms and preserves neurological function, with side effects like hair thinning, diarrhea, and elevated liver enzymes being generally mild. The drug does not compromise immune competence, as evidenced by maintained vaccine responses, and regular hepatic monitoring is recommended, especially for pregnant women or those not using reliable contraception due to potential teratogenic effects. Overall, teriflunomide is considered a valuable addition to MS therapeutic options, offering a favorable balance between efficacy and safety.