Trifluridine (TFT)

Trifluridine is an anti-herpesvirus antiviral drug, used primarily on the eye. It is a nucleoside analogue, a modified form of deoxyuridine, similar enough to be incorporated into viral DNA replication, but the -CF3 group added to the uracil component blocks base pairing. It is a component of the experimental anti-cancer drug TAS-102. Trifluridine (trifluorothymidine) is an antiviral agent for topical use in the eye, and is structurally related to idoxuridine. In vitro studies have shown that it effectively inhibits the replication of herpes simplex virus type 1, which causes primary keratoconjunctivitis and recurrent epithelial keratitis in man. The drug is well tolerated and cross-hypersensitivity and cross-toxicity between trifluridine, idoxuridine and vidarabine are rare. Thus, trifluridine is an effective alternative to the drugs available for treating herpetic keratitis, and seems especially useful in """difficult""" cases.