FDA approves pritelivir (Hovilpri) for treatment-refractory herpes lesions in immunocompromised adults

On 9 October 2026 the US FDA approved Hovilpri (pritelivir) 100 mg tablets from Asahi Kasei Therapeutics (developed by AiCuris, now part of Asahi Kasei).

The approval

• Indication: mucocutaneous lesions caused by herpes simplex virus (HSV) that are refractory (with or without documented resistance) to acyclovir, valacyclovir or famciclovir, in immunocompromised adults.
• Pritelivir is a helicase-primase inhibitor — a different mechanism from standard nucleoside antivirals.
• The FDA lists it as novel drug approval No. 46 of 2026.

Why it matters

In people with blood cancers, transplants, HIV or immunosuppressive treatment, herpes lesions can become prolonged and painful, and existing second-line options carry significant toxicity. The company calls Hovilpri the first approved treatment for this setting with a new mechanism in nearly 30 years.

Limitations

Efficacy and safety details here come largely from the manufacturer’s announcement; the approval covers a narrow, refractory population, and full prescribing information should be consulted for side effects and interactions.