printable versionEffort advances to make affordable vaccine in India
BY ROSANNE SPECTOR
Stanford researchers are part of an unusual project aimed at getting vaccines to children in India. Though still in its early stages, the project reports promising results from phase 1 safety tests of two vaccines for rotavirus—the leading cause of severe diarrhea in children worldwide, mostly in poor countries. It accounts for about 160,000 deaths per year in India alone. In the United States the infection results in about 55,000 hospitalizations per year but rarely causes death.
What's unusual about the project? It's an experiment in drug development as well as medicine. "The goal is to develop a rotavirus vaccine that is developed, tested and manufactured in India that will not only be effective in India, it will be affordable," said Harry Greenberg, MD, the Joseph D. Grant Professor of Medicine and Microbiology and Immunology, who has worked with Indian scientists on the project.
The team hopes the approach will circumvent the problem posed by the high costs of vaccines produced in developed nations such as the United States. The U.S. Food and Drug Administration approved a rotavirus vaccine last month—making it the only rotavirus vaccine approved for use in this country. That vaccine, made by Merck & Co., requires three doses per child, at a cost of $62.50 per dose.
Said Greenberg: "There's frequently about a 20-year gap from when a vaccine is developed in the Western world until it's widely used in the less developed world. That's how long it takes for the price to come down to something affordable. Our idea is to short circuit that problem by producing and testing the vaccine entirely in India from the start."
To reach this goal, Greenberg and Stanford colleague Yvonne Maldonado, MD, associate professor of pediatrics, are working with the U.S. Centers for Disease Control and Prevention, the Indian government's Department of Biotechnology, the Indian Institute of Science, the Society for Advanced Studies in New Delhi and the Indian biotechnology company, Bharat Biotech International Ltd. The project is supported by the nonprofit international health organization, PATH, with funds from the Bill and Melinda Gates Foundation. Prior funding came from the U.S. National Institutes of Health.
Last month the team reported the results of the first human safety tests for the two candidate vaccines—one of which was developed jointly by the CDC and scientists in New Delhi and the other by Greenberg and a team in Bangalore. In the randomized, double-blind trial, which took place in New Delhi, researchers assigned 90 healthy infants ages 8-12 weeks into three groups (30 per group) to receive a placebo or a single oral dose of one of the two vaccines, using pilot lots of the vaccine manufactured in the United States. After treatment they monitored the babies for adverse events and measured their immune responses as well. They found that both vaccines were well-tolerated and safe and that the immune response to the CDC-New Delhi vaccine was promisingly strong. That candidate is being carried forward for additional study.
The next step, said Greenberg, is a larger phase 1 clinical trial, using vaccine manufactured by Bharat Biotech. He and Maldonado will continue with the project, helping to plan the trial, consult on the vaccine production and provide the biological materials used to test the vaccine's effectiveness and safety.