Study Backs Use of Rotarix, Despite Bowel RiskJun 17, 2011 | Parker Waichman LLP
A new study has found a slight risk of a serious bowl disorder associated with GlaxoSmithKline's rotavirus vaccine, Rotarix. Still, authors of the Rotarix study, which was published in the New England Journal of Medicine (NEJM), say the benefits of the vaccine far exceed its risks.
The study confirms that the risk of the bowel disorder - intussusception - was not limited to the RotaShield vaccine, which was pulled from the U.S. market in 1999. According to the Food & Drug Administration (FDA), that vaccine caused intussusception in 1 in 10,000 babies who got it.
According to the Mayo Clinic, intussusception is a condition in which either the colon or small intestine slides into another part of the intestine. This creates a blockage that cuts off the blood supply to the part of the intestine that's affected. The disorder can be fatal, but can often be successfully treated with prompt attention.
The NEJM Rotarix study was conducted by researchers at the U.S. Centers for Disease Control, as well as health agencies in Brazil in Mexico. The study looked at children in those two Latin American countries, and found that between 1 in 51,000 and 1 in 68,000 vaccinated babies given Rotarix will develop intussusception. The researchers noted an increased risk of intussusception 1 to 7 days after the first dose among infants in Mexico vaccinated with Rotarix. There was no significant risk after the first dose in children in Brazil, but some increased risk 1 to 7 days after vaccination.
According to the study authors, data from both countries indicate that about 80,000 hospitalizations and 1,300 deaths are prevented in the two countries every year by vaccinating babies against rotavirus.
An editorial accompanying the study notes that researchers in Australia have reported a small intussusception risk with a Merck vaccine called RotaTeq.
"The vaccines’ pluses so outnumber the minuses that it’s almost immaterial to talk about the minuses,” Greenberg said. “In places like the United States or Western Europe, the new vaccines substantially reduce hospitalizations and morbidity,” Harry Greenberg, MD, author of the editorial writes. "They save hospital costs, plus the cost of work lost to parents who have to bring their child to the doctor or have the child hospitalized.”
Greenberg goes on to write that the research suggests that natural rotavirus infection itself probably causes intussusception at some low frequency.
In March 2010, use of Rotarix was temporarily suspended by the FDA after it was found to contain a pig virus called porcine circovirus 1, or PCV1. But in May of that year, the agency recommended that physicians resume using Rotarix and continue using Merck's RotaTeq, citing their "strong safety records."