--- title: First Potential Zika Vaccine to Start Human Trials description: The U.S. Food and Drug Administration gave the green light on Monday to human experiments with the potential vaccine known as GLS-5700 canonical: https://time.com/4376030/zika-vaccine-human-trials-2/ author: Amanda Calvo article:opinion: false article:content_tier: free article:published_time: 2016-06-21T04:43:28.000Z article:modified_time: 2026-02-22T22:43:55.260Z article:section: Health og:title: First Potential Zika Vaccine to Start Human Trials og:description: However, researchers warn that the journey to market could take years og:url: https://time.com/4376030/zika-vaccine-human-trials-2/ og:site_name: TIME og:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt881b6faaf768229c/698898bca988caee1a6b8511/gettyimages-507783100.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 og:image:width: 1200 og:image:height: 675 og:image:alt: Brazil Faces New Health Epidemic As Mosquito-Borne Zika Virus Spreads Rapidly og:type: article twitter:card: summary_large_image twitter:title: First Potential Zika Vaccine to Start Human Trials twitter:description: However, researchers warn that the journey to market could take years twitter:image: https://static.time.com/v3/assets/bltea6093859af6183b/blt881b6faaf768229c/698898bca988caee1a6b8511/gettyimages-507783100.jpg?branch=production&width=3840&quality=75&auto=webp&crop=16:9 ---  # Human Trials Will Begin Soon for the First Potential Zika Vaccine by [Amanda Calvo](https://time.com/author/amanda-calvo/) ## Amanda Calvo Jun 21, 2016 4:43 AM UTC  A 3-months-old, who has microcephaly, is held by her mother Nadja Cristina Gomes Bezerra on Jan. 31, 2016, in Recife, Brazil A 3-months-old, who has microcephaly, is held by her mother Nadja Cristina Gomes Bezerra on Jan. 31, 2016, in Recife, BrazilMario Tama—Getty Images by [Amanda Calvo](https://time.com/author/amanda-calvo/) ## Amanda Calvo Jun 21, 2016 4:43 AM UTC The U.S. Food and Drug Administration (FDA) gave a green light Monday to the [first human trial of a potential Zika vaccine](https://www.theguardian.com/world/2016/jun/20/human-testing-experimental-zika-vaccine-virus). Inovio Pharmaceuticals and GeneOne Life Science are at the helm of the study and have already conducted promising animal trials. They say [that they will begin phase one with 40 healthy adults](http://ir.inovio.com/news/news-releases/news-releases-details/2016/Inovio-Pharmaceuticals-and-GeneOne-Life-Science-Receive-Approval-for-First-in-Man-Zika-Vaccine-Clinical-Trial/default.aspx) in the next coming weeks. Dubbed GLS-5700, the vaccine is based on synthetic fragments of virus DNA that stimulate antibodies, according to the _Guardian_. Although it could deliver results this year, researchers warn that the journey to market could take years. Also, “since the vaccine would likely be needed for pregnant women or women who are about to become pregnant, the FDA will want to see extensive safety data in these populations,” said Dr. Peter Hotez, dean of the National School of Tropical Medicine at Baylor College in Houston, to the _Guardian_. The WHO declared Zika a global public-health emergency in February. It is primarily spread through mosquito bites but can also be sexually transmitted. More than [1 million cases have been reported across 39 countries and territories](http://time.com/4369520/risk-of-zika-spreading-globally-during-olympics-very-low-who-says/). Although the disease effects are mild for the majority of people infected, it has been linked to Guillain-Barré syndrome and causes complications for pregnant women, with nearly [5,000 cases reported in Brazil](http://www.reuters.com/article/us-health-zika-brazil-idUSKCN0XN2NP) of newborns with the birth defect microcephaly. The mosquito-borne disease currently has no treatment or vaccine. \[[_Guardian_](https://www.theguardian.com/world/2016/jun/20/human-testing-experimental-zika-vaccine-virus)\] ```json [{"@context":"https://schema.org","@type":"NewsArticle","@id":"https://time.com/4376030/zika-vaccine-human-trials-2/","mainEntityOfPage":{"@type":"WebPage","@id":"https://time.com/4376030/zika-vaccine-human-trials-2/"},"headline":"Human Trials Will Begin Soon for the First Potential Zika Vaccine","datePublished":"2016-06-21T04:43:28.000Z","dateModified":"2026-02-22T22:43:55.260Z","description":"However, researchers warn that the journey to market could take years","url":"https://time.com/4376030/zika-vaccine-human-trials-2/","keywords":["Infectious Disease","Disease","brazil","WHO","infection","vaccine","Zika"],"thumbnailUrl":"https://static.time.com/v3/assets/bltea6093859af6183b/blt881b6faaf768229c/698898bca988caee1a6b8511/gettyimages-507783100.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","author":[{"@type":"Person","name":"Amanda Calvo","jobTitle":null,"url":"https://time.com/author/amanda-calvo/"}],"articleSection":"Health","image":[{"@type":"ImageObject","url":"https://static.time.com/v3/assets/bltea6093859af6183b/blt881b6faaf768229c/698898bca988caee1a6b8511/gettyimages-507783100.jpg?branch=production&width=1200&quality=75&auto=webp&crop=1200:675&height=675","width":1200,"height":675,"headline":"Brazil Faces New Health Epidemic As Mosquito-Borne Zika Virus Spreads Rapidly","caption":"Brazil Faces New Health Epidemic As Mosquito-Borne Zika Virus Spreads Rapidly","creditText":"Mario Tama—Getty Images","representativeOfPage":true}],"publisher":{"@type":"Organization","name":"Time","url":"https://time.com/","logo":{"@type":"ImageObject","url":"https://time.com/images/logo.png","width":528,"height":156},"foundingDate":"March 3, 1923","sameAs":["https://www.facebook.com/time","https://www.instagram.com/time/?hl=en","https://twitter.com/time","https://www.pinterest.com/timemagazine"]}},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"/section/health/","name":"Health"}},{"@type":"ListItem","position":2,"item":{"@id":"/tag/infectious-disease/","name":"Infectious Disease"}},{"@type":"ListItem","position":3,"item":{"@id":"https://time.com/4376030/zika-vaccine-human-trials-2/","name":"Human Trials Will Begin Soon for the First Potential Zika Vaccine"}}]}] ```