Rotavirus, the most common cause of severe diarrhea among infants and young children, causes somewhere approaching a half million deaths annually, 100,000 of them in India and half of those among children less than a year old.
So the positive results announced today for a Phase III clinical trial of a rotavirus vaccine developed and manufactured in India are great news. The new vaccine cut cases of severe rotavirus-induced diarrhea by more than half - 56 percent - during the first year of life, with protection continuing into the second year of life. That compares favorably with the efficacy of the currently licensed rotavirus vaccines in low-income parts of the globe.
An Indian company, Bharat Biotech, sponsored the randomized, double-blind, placebo-controlled study and will soon file for registration of the vaccine in India.
The trial was conducted at three sites in India. About 6,800 infants who were between six and eight weeks old when they were enrolled received either the vaccine or a placebo in three doses spread over about two months, simultaneously with their routine immunizations for polio.
Stanford virologist Harry Greenberg, MD, a professor of medicine and of microbiology and immunology and the medical school's senior associate dean for research, is a member of the senior scientific advisory group involved in all aspects of the vaccine's development. Greenberg's own past research was instrumental in producing the first-ever rotavirus vaccine, licensed in 1998. That vaccine was pulled off the market upon the discovery of a rare but life-threatening side effect called intussusception. But a study published in the New England Journal of Medicine in 2011 showed that intussusception risk is not only vastly outweighed by the benefits of vaccination, but may actually be at least as strongly associated with rotavirus infection itself as with the vaccine.
Two companies' competing rotavirus vaccines are already licensed. But with one costing about $37 per two-dose course and the other going for about $50 per three-dose course, they're prohibitively expensive for the vast majority of Indians. Bharat, the Indian biotech, has stated that it will sell this vaccine (its brand name is ROTAVAC) for a dollar a dose. At that price, assuming the product's approval, it will save many, many thousands of lives every year.