teriflunomide

Teriflunomide is an oral immunomodulatory drug approved for adults with relapsing forms of multiple sclerosis (MS). It is the active metabolite of leflunomide and is marketed under the brand name Aubagio. Teriflunomide inhibits dihydroorotate dehydrogenase (DHODH), a key enzyme in de novo pyrimidine synthesis, leading to reduced proliferation of activated T and B lymphocytes and a modulated immune response.

In clinical use, teriflunomide aims to reduce relapse rate and MRI activity and to slow disability progression in relapsing MS. The usual dose is 14 mg once daily, taken orally with or without food. Therapy is continued based on clinical response and tolerability; it is not curative.

Safety and monitoring information emphasizes hepatotoxicity and infection risk. Common adverse effects include hair thinning, diarrhea, nausea, headaches, and mild liver enzyme elevations, with others such as hypertension or upper respiratory infections reported. Patients should have baseline liver function tests and periodic monitoring during treatment, and teriflunomide should be stopped if there is significant liver injury. The drug is teratogenic and contraindicated in pregnancy. Women of childbearing potential must use effective contraception during treatment and for a period after stopping; men taking teriflunomide are also advised to use contraception. Because teriflunomide has a long elimination half-life, its therapeutic effects and presence in the body can persist for months after discontinuation; accelerated elimination with cholestyramine or activated charcoal can markedly shorten this time if pregnancy is planned or if rapid drug removal is needed.

Special considerations include potential drug interactions, particularly with other hepatotoxic agents, and the importance of avoiding live vaccines during teriflunomide therapy. Caution is advised in patients with preexisting liver disease or significant hepatic impairment.