The race to develop a safe and effective vaccine against the Zika virus got one step closer Thursday, when a team of researchers reported positive results in the latest round of testing in monkeys.
Three experimental vaccines being developed by researchers at Harvard Medical Hospital and the Walter Reed Army Institute of Research had already shown promise in mice — but monkeys are a much better model of how the medicines will work in humans.
All three vaccines were found to be safe and protected the monkeys against infection with the virus, according to the report published in Science, NBC News reported.
The urgency for a vaccine to protect against Zika infection has intensified as the virus spreads rapidly across Latin America and the Caribbean. This week an unprecedented travel advisory was given for southern Florida after more than a dozen people were diagnosed with Zika after being bitten by “homegrown” mosquitoes.
Zika virus is most dangerous to pregnant women, because it can cause severe birth defects in babies if they are infected in the womb.
Right now, just one of those three vaccines will be progressing to clinical trials. That vaccine — dubbed ZPIV for purified inactivated Zika virus — uses a more traditional vaccine approach and depends on dead virus particles.
To continue the development of the vaccine, researchers will be partnering up with the largest pharmaceutical company solely devoted to vaccines, Sanofi Pasteur and hope to test the vaccine in people by October, said Dr. Dan Barouch, study coauthor and a professor of medicine at Harvard Medical School.
Results Striking
Researchers in the study tested 16 monkeys with an initial dose of ZPIV and a booster four weeks later. Then the monkeys were exposed to active forms of the virus.
The results were “striking,” Barouch said. “The findings substantially increase our optimism for the potential for the development of a Zika vaccine for humans.”
Beyond that, “this is a promising [vaccine] candidate that can be easily produced in large quantities,” said coauthor, Col. Nelson Michael, an army doctor who specializes in flaviviruses, such as Zika and dengue.
