The Phase 1 trial will test the safety and immunogenicity -- the ability of the vaccine to trigger an immune response in the body -- of the purified, inactivated Zika virus vaccine called ZPIV. The vaccine is being tested at WRAIR’s Clinical Trial Center in Silver Spring, Maryland.
“The Army has moved efficiently from recognizing Zika virus as a threat, producing ZPIV for use in animals and demonstrating its effectiveness in mice and monkeys, producing ZPIV for human testing, and now initiating clinical trials to establish its safety and build the case for subsequent efficacy trials,” Army Col. (Dr.) Nelson Michael, director of WRAIR’s Military HIV Research Program, or MHRP, and Zika program co-lead, said in a statement.
As of Nov. 2, according to the Centers for Disease Control and Prevention, 149 cases of Zika infection were confirmed in the military health system, including four pregnant service members and one pregnant family member.
Zika infection during pregnancy, CDC says, can cause a birth defect of the brain called microcephaly and other severe fetal brain defects.
Other problems have been detected among fetuses and infants infected with Zika virus before birth, such as defects of the eye, hearing deficits and impaired growth. And reports have increased about Guillain-Barré syndrome, an uncommon sickness of the nervous system, in areas affected by Zika, CDC says.
But even Zika infections without symptoms “can lead to severe birth defects and neurological complications,” Zika study principal investigator Army Maj. (Dr.) Leyi Lin said, adding, “A safe and effective Zika vaccine that prevents infection in those at risk is a global public-health priority."
Zika Vaccine Platform
WRAIR’s inactivated flavivirus vaccine platform was the same technology the institute used to create its Japanese encephalitis vaccine, licensed in 2009.
An earlier preclinical study found that rhesus monkeys vaccinated with ZPIV developed a strong immune response and were protected against two strains of Zika virus.