FDA Panel Backs Rotateq

Updated from 1:14 p.m. EST

A panel of medical experts on Wednesday said the Food and Drug Administration should approve a Merck (MRK) vaccine designed to prevent a debilitating and deadly gastrointestinal disease that's caused by a virus.

The advisory panel endorsed Merck's Rotateq, which would be the first U.S. vaccine to fight gastroenteritis caused by the rotavirus. Merck says the virus is a major cause of diarrhea-related hospitalizations worldwide. The virus annually kills nearly 500,000 children under age 5.

In the U.S., rotavirus causes about 50,000 hospitalizations and 20 to 40 deaths a year, Merck says. The company is seeking FDA approval of the vaccine for infants and young children, and it plans to conduct clinical trials in Africa and Asia, with the goal of starting at least one study by the end of 2006.

The FDA isn't bound by recommendations of its advisory panels, but it usually follows their lead.

Rotateq is one of three experimental Merck vaccines now before the FDA. On Thursday, a medical-experts panel is scheduled to vote on Zostavax. If it's ultimately approved, Zostavax would be the first vaccine against shingles.

Earlier this month, Merck submitted an application for Gardasil, a vaccine designed to block the human papillomavirus, or HPV, which can cause cervical cancer and genital warts. Gardasil would be the first vaccine against HPV if it gets regulatory clearance.

Merck's stock gained 43 cents, or 1%, closing at $29.20 on heavier-than-average volume.

Earlier Wednesday, an FDA staff report said the shingles vaccine, Zostavax, appears to be safe and effective. But the report adds that the vaccine's potency wanes over time and age plays a key role in how well it works. FDA staff reports are routinely issued prior to advisory panel meetings.

Shingles, or herpes zoster, is a viral infection of nerve roots that can lead to burning and tingling sensations, as well as a rash or skin blisters. The condition is most common in people older than age 50, and Merck is seeking approval of Zostavax to treat patients who are at least that old. Anyone who has had chickenpox is vulnerable to shingles.