New Rotavirus Vaccine is "First of its Kind": Affordable & Heat-Stable

Rotavirus, a contagious virus that can cause gastroenteritis, most commonly plagues infants and children. The virus also accounts for 37% of diarrhea-related deaths among children under the age of 5, and so researchers are scrambling for new ways to reduce its devastating death toll.

Now, Harvard T. H. Chan School of Public Health and Epicentre, Paris, are sharing the results of a new study that shows a new rotavirus vaccine, dubbed BRV-PV, has proven to be 66.7% effective in preventing severe gastroenteritis caused by the virus. The study is published in the New England Journal of Medicine.

Rotavirus can be easily transmitted through contact with contaminated hands, toys, food, or water, according to the Centers for Disease Control and Prevention. In fact, the virus can spread before and after children “become sick with diarrhea.”

However, rotavirus is unique from other causes of diarrhea in that any “improvements” that are made pertaining to water, sanitation, and hygiene, are moot; the efforts will not work when it comes to preventing transmission. The researchers stress that this makes vaccination against the rotavirus even more imperative to preventing diarrhea-associated complications, or even death.

A past study reported that in 2008, rotavirus was responsible for a staggering 453,000 deaths, with most of these deaths occurring in developing countries of sub-Saharan Africa and South-East Asia. In that study, researchers stressed the need to “accelerate the introduction of vaccines” in those areas where rotavirus burden is highest. Researchers from Harvard T. H. Chan School of Public Health stress that in these areas, where healthcare access is low and rotavirus prevalence is high, not only is a safe and effective vaccine needed, but it also needs to be affordable.

Two rotavirus vaccines are currently available in the United States: RotaTeq (RV5) and Rotarix (RV1). However, the researchers from Harvard note that there are two problems when it comes to these vaccines: (1) they are expensive and (2) they must remain refrigerated “throughout the supply chain.” When it comes to administering vaccines in developing countries, such as Niger, where resources are limited, refrigeration can be an issue.

However, the new rotavirus vaccine, BRV-PV, has managed to overcome such an obstacle. How? BRV-PV is heat-stable, making the vaccine “the first of its kind for rotavirus prevention.”

First author on the study, Sheila Isanaka, ScD, assistant professor of nutrition at Harvard Chan School explained in the university press release, “This trial brings a vaccine which is adapted to African settings to those who need it most.” She continued, “When the vaccine becomes widely available in Africa, it will help protect millions of the most vulnerable children.”

For the new study, the researchers conducted a randomized, placebo-controlled trial, held in Niger, one of the poorest countries in the world, with the goal of gauging the effectiveness of the new vaccine. In the trial, 3508 healthy infants received three doses of either the new vaccine, BRV-PV, or placebo at 6 weeks of age, 10 weeks of age, and finally, 14 weeks of age. The researchers noted that all the children participating in the trial “are monitored at local health centers and receive healthcare for two years.”

According the information on the trial on ClinicalTrial.gov, the, “live attenuated bovine-human [UK] reassortant rotavirus vaccine manufactured by the Serum Institute of India, Limited (SIIL). The pentavalent vaccine (BRV-PV) contains rotavirus serotypes G1, G2, G3, G4, and G9 (≥5.6 log10 FFU/serotype/dose). The vaccine is in lyophilized form [freeze-dried] and supplied with 2.5 ml of citrate bicarbonate buffer that is added for reconstitution just before oral administration.” BRV-PV is already licensed in India; however, approval from the World Health Organization is still needed before the United Nations or government agencies can obtain it to make it available to the countries that need it most.

When speaking of potential next steps for this vaccine, Dr. Isanaka said, “After the successful clinical trial of this new vaccine, we hope that it can be made available as soon as possible to children in Niger and across Africa.”