Brivudine: A herpes virostatic with rapid antiviral activity and once-daily dosing

Brivudine is an analog of thymidine, and is incorporated into the viral DNA. It blocks the action of DNA polymerases, thus inhibiting viral replication. It has a stronger antiviral effect against the varicella-zoster virus compared with reference compounds such as aciclovir or penciclovir. The efficacy of brivudine has been documented in a number of clinical trials in patients with herpesvirus-related infections, particularly in patients with herpes-zoster. At a dose of 125 mg once daily, brivudine has proved to be superior to aciclovir with respect to reducing the period of new blister production in patients with herpes-zoster, and has shortened the duration of post-herpetic neuralgia. Tolerability was equivalent to that of aciclovir or placebo, with occasional gastrointestinal disorders leading to treatment withdrawal in a minority of patients.