More studies back patient-initiated herpes therapy.(NEWS)

SAN FRANCISCO -- A single, patient-initiated dose of famciclovir cut short recurrent outbreaks of herpes labialis by 2 days, Dr. Marcus Conant said at the annual meeting of the American Academy of Dermatology.

Viral replication of the herpes simplex virus type 1 lasts 8 hours. Famciclovir remains in a cell for 10 hours, Dr. Conant explained during a forum highlighting new data from clinical trials.

Given this "window of opportunity ... you ought to be able to treat the patient with high-dose famciclovir if it's initiated early in the course of an outbreak," he said. "That was the idea behind this study."

Patients recruited from sites in the United States, Canada, and Australia were eligible for the study if they had healthy immune function and a history of prodromal symptoms and vesicle formation associated with at least half of their previous facial herpes outbreaks.

Among 1,376 subjects who met the criteria, 477 experienced symptoms, initiated therapy within an hour, and developed vesicles. This modified intent-to-treat population did not include patients who failed to develop vesicles.

The time to healing of primary vesicular lesions was 4.4 days in 152 patients randomized to receive 1,500 mg of famciclovir in a single dose; 4 days in 157 patients who took 2 doses of 750 mg each on the first day; and 6.2 days in 168 patients who received placebo.

The time to healing of all vesicular lesions was 4.5 days and 4.1 days in the single- and split-dose treatment groups and 6.6 days in patients assigned to placebo.