FDA Suspends Rotarix Vaccine Due to Viral Contamination
The US Food and Drug Administration recommended that doctors stop using Rotarix, one of two vaccines licensed for use against rotavirus. Administration Commissioner Dr. Margaret Hamburg said that the vaccine is contaminated with material from a pig virus, but that “there is no evidence at this time that this material poses a safety risk.”
Rotavirus is a disease that kills more than 500,000 infants around the world each year, primarily in developing countries. It causes severe diarrhea and dehydration. In the US, rotavirus was once responsible for more than 50,000 hospitalizations and several dozen deaths before a vaccine became available.
Rotarix, made by GlaxoSmithKline, was approved by the FDA in 2008. The vaccine is given orally in two doses to infants starting at 2 months of age. It is made from a weakened strain of human rotavirus that must grow inside a living cell before being purified into a vaccine dose. About 1 million children in the US and about 30 million worldwide have received the Rotarix vaccine.
The contaminant material found in the Rotarix vaccine is DNA from porcine circovirus 1 (PCV-1), a virus from pigs that is not known to cause disease in humans or other animals. It is found in everyday meat products and is frequently eaten without adverse consequences. The FDA learned of the contamination after an academic research team found it during a test of a new technique to test for viruses in vaccines.
GlaxoSmithKline confirmed the presence of the virus in both the cell bank and the seed from which the vaccine is derived, suggesting that it has been present since the early stages of the vaccine development and throughout its clinical trials. Thomas Breuer, chief medical officer of GSK said, "GSK is committed to patient safety and to the highest manufacturing standards for all our vaccines and medicines. We are already working closely and discussing this finding with regulatory agencies around the world."
Dr. Hamburg wants to reassure the public that the Rotarix virus is not being pulled from the market, but the agency is just erring on the safe side. “We’re just suspending its use during this period while we’re collecting more information. It should not be in this vaccine product and we want to understand how it got there.” She also emphasized that the vaccine suspension applies only to the US, as countries where rotavirus is more severe, the benefits of the vaccine may outweigh the possible risks.
The other approved vaccine in the US, RotaTeq made by Merck and approved in 2006, appears to be safe. It is made using a different process than the GSK vaccine, and preliminary testing has found no evidence of the porcine DNA. Merck spokeswoman Pam Eisele has said that her company will work with the FDA to evaluate supply needs while the GSK product is suspended.
Children who have already received one dose of Rotarix and are pending the second should switch to RotaTeq, which will require an additional dose. Children already vaccinated with both doses of Rotarix do not need to do anything at this time. Doctors should be able to tell parents which of the two products their children received – about 75% of US doctors already prescribe the Merck brand over the GSK vaccine.
An advisory panel will meet in the coming weeks to evaluate the next steps of the investigation.