Novavax, a clinical-stage vaccine company focused on the discovery, development and commercialization of recombinant nanoparticle vaccines and adjuvants, has announced positive top-line data from a phase I clinical trial of its Ebola virus glycoprotein (GP) recombinant nanoparticle vaccine candidate adjuvanted with Matrix-M as part of the World Health Organization's (WHO) Fifth Teleconference on Ebola Vaccine Clinical Trials. The trial demonstrated that the Ebola GP Vaccine was highly immunogenic, well-tolerated and, in conjunction with Novavax' proprietary Matrix-M adjuvant, resulted in significant antigen dose-sparing. 

The Ebola GP Vaccine clinical trial is a randomized, observer-blinded, dose-escalation trial to evaluate the safety and immunogenicity of the vaccine, with and without Matrix-M, in 230 healthy adults between 18 and 49 years of age. Participants received either one or two intramuscular injections ranging from 6.5ug to 50ug of antigen on study days zero and 21. Immunogenicity was assessed at multiple time points including days 28 and 35.

The adjuvanted Ebola GP Vaccine was highly immunogenic at all dose levels. The adjuvanted, two-dose regimens induced Ebola anti-GP antibody geometric mean responses between 45,000 and 70,000 ELISA units (GMEU), representing a 500 to 750-fold rise over baseline at day 35. The adjuvanted single dose vaccine regimen induced GMEU between 1700 and 3400, representing a 21 to 27-fold rise over baseline at day 35.

"We are pleased to have the opportunity to share these positive data with the WHO. Novavax' recombinant nanoparticle technology and proprietary Matrix-M adjuvant differentiates our Ebola GP Vaccine. The phase I clinical data show that our vaccine was well-tolerated and elicited very high Ebola antibody responses," said Gregory Glenn, M.D., senior vice president, R&D. "These data, together with two positive challenge studies in non-human primates, suggest that the Ebola GP Vaccine would be protective in humans."

Stanley C. Erck, president and CEO said, "These positive data represent the third time Novavax has leveraged the power of our platform technology to rapidly address an emerging threat. These Ebola GP Vaccine data, in combination with clinical data from our H7N9 VLP vaccine candidate and preclinical data from our vaccine candidate for Middle East Respiratory Syndrome coronavirus, provide additional validation of our nanoparticle vaccine platform. Our Ebola GP Vaccine, adjuvanted with Matrix-M, was highly immunogenic at low doses, allowing for dose-sparing. Further, our recombinant vaccines do not need to be shipped or stored frozen, a key consideration for a vaccine developed against a novel lethal virus with pandemic potential."