Tenth anniversary of RotaTeq salutes inventors, success, future global approvals

PHILADELPHIA — The Children’s Hospital of Philadelphia and The Wistar Institute recently celebrated the 10th anniversary of the two vaccines that block the microbe rotavirus, a gastrointestinal condition that incurs life-threatening vomiting and diarrhea in young children.

The institutions collaborated in the early 1980s to research solutions to prevent rotavirus, and RotaTeq (Merck) was approved by the FDA and added to the list of routine childhood vaccinations in 2006. A second rotavirus vaccine, Rotarix (GlaxoSmithKline), was approved in 2008, and both vaccines have significantly decreased rotavirus death and infection rates in the United States and Europe.

“This event is a great opportunity to celebrate the development, implementation and impact of the RotaTeq vaccine, but most importantly to tell the story of the scientists involved, the hurdles and success of the work and the incredible impact that was made across the globe,” Dario C. Altieri, MD, president and CEO of The Wistar Institute and director of Wistar’s Cancer Center, said in a press release.

Paul A. Offit

The event was highlighted by a six-person panel of experts from The Wistar Institute, The Children’s Hospital of Philadelphia (CHOP), and the CDC. The panel included Paul A. Offit, MD; Stanley A. Plotkin, MD, co-inventors of RotaTeq; and Penny M. Heaton, MD; who chaired the development team for the RotaTeq vaccine while serving as senior director for vaccine clinical research at Merck.

Prior to the vaccines’ development in the U.S., several million children were affected by rotavirus.

“Over 250,000 children would visit the emergency departments every year, about 75,000 would be hospitalized, and 20 to 60 children would die every year,” Offit, director of the Vaccine Education Center at CHOP, told Infectious Diseases in Children during the celebration on Oct. 6. “In the developing world, rotavirus took the lives of about 2,000 children a day. As a single pathogen, rotavirus accounted for more disease and infection among infants and young children.

“Every year [in the U.S.], we have more and more children getting vaccinated with the rotavirus vaccine, and there’s herd immunity, so when there was a 50% immunization rate, there was an 85% reduction in disease.”

Rates of intussusception, a serious adverse event, decreased significantly after the FDA approvals of RotaTeq and Rotarix compared with RotaShield (Wyeth), the first rotavirus gastroenteritis vaccine, Plotkin said in an interview.

“The increased risk still exists, but it’s far less than it was with RotaShield, [which was removed from the market in 1999]. The rate of intussusception is probably 1 in 100,000 vaccinees,” Plotkin, professor emeritus at the University of Pennsylvania and adjunct professor at Johns Hopkins University, said. “And one has to remember that intussusception, or intestinal invagination, is something that occurs in infants anyway. The vaccination does slightly increase the incidence, but, the interesting thing is that [with the vaccine] intussusception occurs for different reasons.”

Though widespread success with RotaTeq and Rotarix has occurred in the U.S., global vaccination is still a problem in developing countries.

“There’s still not enough manufacturing of the vaccine to sustain a global supply, so we need to get more manufacturers to import when they are approved and when the vaccines are WHO prequalified,” Heaton, director of vaccine development for the Bill & Melinda Gates Foundation, told Infectious Diseases in Children. “That’s one issue; a second issue is with the current vaccines; the characteristics aren’t optimal for low-income countries. The tubes the vaccine comes in take up too much space in the cold chain of the refrigerator, so we are working to get more refrigerators, and also getting the manufacturers to potentially develop a smaller tube.

“The third issue is the vaccine is sometimes not as efficacious in developing countries as it is in the U.S. and Europe.”

Heaton said a third rotavirus vaccine was approved in India in March, and she and her colleagues are supporting development of several new vaccines in a campaign championing an effort to bring them to developing countries. – by Kate Sherrer

Disclosures: The researchers reported no relevant disclosures.