Merck rotavirus vaccine label to cite disease data

WASHINGTON (Reuters) - The label for Merck & Co Inc.'s rotavirus vaccine will include reports of a serious illness called Kawasaki disease in some children who received the oral vaccination, U.S. health officials said on Friday.

The Food and Drug Administration said doctors and parents should "remain confident" in the Rotateq vaccine. The number of cases did not exceed what would be expected for young children who were not vaccinated, the FDA said.

Kawasaki disease is a serious but uncommon illness in children that causes high fever and blood-vessel inflammation. The FDA said about 4,000 U.S. children, about 80 percent under age five, develop it each year. The cause is unknown.

Rotavirus infection can cause severe infant diarrhea that requires hospitalization. The virus is a major killer of children in developing countries, but deaths in the United States are rare.

Five cases of Kawasaki disease were reported among more than 35,000 infants who received Rotateq in clinical trials, the FDA said. One case appeared in others who got a placebo.

Three more cases have been reported in children who got Rotateq after its approval in February 2006. About 6 million doses of the vaccine have been distributed.

"There is not a known cause and effect relationship between receiving Rotateq, or any other vaccine, and the occurrence of Kawasaki disease. The cases reported to date are not more frequent than what could be expected to occur by coincidence," an FDA statement said.

Merck reported Rotateq sales of $85 million for the first quarter of 2007.

Merck spokeswoman Amy Rose said the company had added the information to the vaccine's prescribing instructions. "The safety profile of Rotateq has been extensively studied," she added.