FDA Clarifies Development of Recurrent Herpes Labialis Candidates

The FDA is providing recommendations on clinical trial designs for sponsors developing antiviral drugs to prevent and treat recurrent herpes labialis, or herpes-related sores that form around the mouth.

The draft guidance covers the overall development — including nonclinical and clinical aspects — of drug candidates for treating and preventing these sores. The document is intended to shepherd more candidates through the process, because no preventative drugs have been approved, although there are a number of treatment options available.

For an investigational drug, the agency encourages sponsors to conduct proof­-of-concept and dose-ranging Phase 2 trials. Once a candidate reaches the Phase 3 stage, the FDA recommends conducting two trials. The Phase 2 and Phase 3 trials can have similar designs and be used to substantiate efficacy, the draft guidance states.