About The Study
This study compared sorivudine (BVaraU) with acyclovir in treating localized herpes zoster.
This was a parallel, double-blinded study (neither doctors nor volunteers knew which therapy volunteers received). Participants were randomly assigned to receive either sorivudine (40 mg daily) or acyclovir (800 mg five times daily) for seven days, for the treatment of acute localized, non-ophthalmic (not involving the eye) herpes zoster. Each patient was entered into the study within 72 hours of lesion development, and the primary endpoint of the study was when new lesions stopped forming.
One hundred and thirty-seven patients, 54 of them in Canada, were assigned to one of two treatments. There were 48 centres in Europe, Canada, Australia and New Zealand.
Sorivudine decreased the time it took for new lesions to stop forming (three days vs four days in the acyclovir group), and the time to reach 50% crusting (five days vs six days). There were significantly fewer recurrences or new episodes of herpes zoster in the sorivudine group (7/65, 10%) compared to the acyclovir group (16/68, 24%). The incidence, maximum intensity and duration of acute neuritis (inflammation of the nerves) and neuralgia (sharp, intermittent pain along the course of a nerve) did not differ between the two treatment groups. There was no difference in the use of pain-relieving drugs between the two groups. The effects on quality of life, measured by the degree of sleep and activity impairment, did not differ between the two treatment groups. Sorivudine therapy was well tolerated and its tolerance was comparable to acyclovir.
Sorivudine decreased the time it took for new lesions to stop forming. It also decreased the time to reach full crusting, by one-third compared to acyclovir.