Investigational Herpes Drug Limits Viral Shedding in Phase II Trial — Physician’s First Watch
Investigational Herpes Drug Limits Viral Shedding in Phase II Trial
By Kelly Young
Pritelivir, the first in a new class of drugs (a helicase-primase inhibitor) for herpes simplex virus, effectively suppressed viral shedding and development of genital lesions in an industry-conducted, phase II trial published in the New England Journal of Medicine.
Roughly 150 patients seropositive for HSV-2 and clinically symptomatic were randomized to receive pritelivir or placebo for 28 days. Participants provided daily genital swabs. The primary outcome — the number of days of viral shedding — was significantly lower in the higher-dose treatment groups (16.6% for placebo vs. 2.1% for 75 mg daily and 5.3% for 400 mg weekly). When breakthrough shedding occurred, pritelivir use was associated with fewer DNA copies of the virus, compared with placebo.
Last May, the FDA placed clinical development of pritelivir on hold after studies in monkeys found dermal and hematologic toxicity. The authors say the current study did not show increased adverse events.