It's a rotavirus reprieve. An FDA panel backed continued use of vaccines against the diarrhea-causing germ from both Merck (NYSE: MRK) and GlaxoSmithKline (NYSE: GSK), in spite of trace contamination with DNA from a pig virus. The move is one step toward reinstatement of GSK's Rotarix vaccine, which has been suspended since March from the U.S. market as a precautionary measure.
The FDA originally suspended Rotarix after researchers found DNA from a pig virus known as PCV1 in the vaccine. The same testing procedures didn't uncover DNA contamination in Merck's Rotateq product at the time. But new, more sensitive tests detected small amounts of the same virus--and a related one known as PCV2--in Rotateq.
The advisory panel reviewed the rotavirus-fighting benefits of the vaccines and said that they are worth the risks. "PCV is not infectious in humans," Harry Greenberg, a panel member and Stanford University professor, said (as quoted by the Wall Street Journal). "The benefits far outweigh the risks." A CDC official said that, given current knowledge about PCV and about the vaccines' effectiveness, any risks "are at best theoretical."
The FDA will make new recommendations on use of the vaccines "in the very near future," one official told reporters (as quoted by Reuters). "We need to consider this very expeditiously." Until then, Rotarix will remain in suspension, with Rotateq still on the market.