Merck & Co., Inc. has submitted to the US FDA a Biologics License Application for Zostavax [zoster vaccine live (Oka/Merck)], an investigational vaccine for the prevention of herpes zoster, commonly known as "shingles;" prevention of postherpetic neuralgia (PHN), the persistent, long-term nerve pain that is the most common complication of shingles; and the reduction of acute and chronic shingles-associated pain in adults.

Merck submitted the application for Zostavax on April 25. Within the next 60 days, the FDA will determine whether it will accept for review Merck's application as submitted.

Shingles occurs when the varicella-zoster virus that causes chickenpox reactivates after lying dormant in the body, typically after several decades. Shingles may first appear as tingling, itching or pain on one side of the body or face. It then progresses to a blistering rash accompanied by pain in almost every case that varies in intensity and duration. Shingles also can lead to complications, including persistent, often debilitating nerve pain (PHN) that can follow an episode of shingles. Approximately 25 to 50 per cent of shingles patients older than 50 years of age develop chronic pain after shingles (PHN).