Inovio Pharmaceuticals, Inc. today announced its DNA-based Zika vaccine (GLS-5700) generated robust antigen-specific antibody responses in a first-in-man, multi-center phase I trial. In initial testing, Zika-naïve subjects in both low dose and high dose vaccine groups demonstrated Zika antigen-specific antibody responses after one or two vaccinations. In addition, the vaccine was well tolerated and no significant safety concerns were noted in any of the 40 subjects out to 14 weeks from initiation of dosing, the latest available data from the study.


This phase I, open-label, dose-ranging study of GLS-5700 in healthy adult volunteers is evaluating the safety, tolerability and induction and persistence of Zika specific antibody and T cell responses out to 60 weeks. In preclinical testing Inovio’s Zika vaccine protected animals that had been exposed to the virus from infection, brain damage and death.

Dr. J. Joseph Kim, Inovio’s President & CEO, said, “These early clinical results show that Inovio is on track to rapidly develop Zika countermeasures for this disease that has no currently existing vaccine or treatment. Our synthetic vaccine technology allows rapid development of new products, leading Inovio to be the first to create a Zika vaccine, the first to generate preclinical data, the first to initiate human testing, and now first to report positive clinical data.”

“We also look forward to completing our second phase I study of 160 subjects in Puerto Rico, where the CDC estimates 25% of the population could be infected with Zika virus by year end. We expect results next year which may provide exploratory signals of vaccine efficacy. Based on these two studies, we plan to meet with regulators to map out the most efficient path forward to bring our Zika vaccine to patients and help mitigate this widespread Zika outbreak that has expanded into the continental United States.”

Inovio is developing its Zika vaccine, GLS-5700, with GeneOne Life Science, Inc. (KSE:011000) and academic collaborators from the U.S. and Canada who are also collaborating to advance clinical development of Inovio’s Ebola and MERS vaccines.

In addition to the vaccine development, earlier this month, Inovio and The Wistar Institute received an $8.8 million grant from the Bill & Melinda Gates Foundation to develop a DNA-based monoclonal antibody designed to provide fast-acting protection against Zika infection and its debilitating effects. Unlike vaccines, monoclonal antibody-based therapies could provide more immediate protection but do not develop long-term immune memory. An ideal approach would therefore include the co-administration of a dMAb™ product for immediate protection and a DNA vaccine to train the immune system for longer-term, persistent protection against Zika infection.