National Institutes of Health's (NIH) National Institute of Allergy and Infectious Diseases (NIAID) has begun the Phase II/IIb clinical trial of a Zika vaccine for protection against disease related to the Zika infection.
Developed by government scientists at the NIAID’s Vaccine Research Center (VRC), the NIAID Zika virus investigational DNA vaccine is comprised of a plasmid integrated with genes that encode two proteins found on the surface of the Zika virus.
The vaccine induces the body’s immune response by assembling the encoded proteins into particles that imitate the Zika virus.
The two-part VRC 705 trial is designed to enrol up to 2,490 healthy participants in the continental US and Puerto Rico, Brazil, Peru, Costa Rica, Panama and Mexico.
NIAID director Anthony Fauci said: "Evidence also is accumulating that Zika can cause a variety of health problems in adults as well.
"This trial marks a significant milestone in our efforts to develop countermeasures for a pandemic in progress.”
Part A of the trial will assess the safety and ability of the vaccine to trigger an immune response in 90 healthy men and non-pregnant women aged 18-35 at three sites in Houston, Miami and San Juan, Puerto Rico.
This part will also establish the optimal dose and injection sites for administration.
Part B of the trial will evaluate the effectiveness of the vaccine to protect against Zika-related disease when naturally exposed to the virus in 2,400 healthy men and non-pregnant women aged 15-35.
It will be conducted at two sites in San Juan, two in Costa Rica, and one each in Peru, Brazil, Panama and Mexico, in addition to the Part A sites.
Image: A vial of the NIAID Zika Virus Investigational DNA Vaccine. Photo: courtesy of NIAID.