One of the vaccines, known as VRC5288, has already begun early trials in humans to test safety and efficacy, according to a study published in Science.
A phase 2 trial in Zika-endemic countries could begin next year, officials said.
The second vaccine (VRC5283) is awaiting a Phase 1 clinical trial start date.
The research involved vaccinating rhesus macaques using “the two different experimental Zika DNA vaccines in different doses,” said the NIH in a statement.
Two doses were “highly effective” at protecting macaques exposed to an infectious dose of Zika virus.
Experts say it will be years before a vaccine is developed to prevent infection from Zika, which is particularly dangerous to pregnant women because it can cause brain defects in the fetus.
