A Covid-19 vaccine developed by US-based Novavax elicited robust antibody responses and appeared to be safe in a Phase-I human trial, the company has said.No serious adverse events were reported and safety follow-up continues, Novavax said on Tuesday, while releasing the results of the study about its Covid-19 vaccine, NVX-CoV2373.The trial evaluated two doses of the vaccine across two dose levels -- 5 and 25 microgram -- in 131 healthy adults ages 18-59 years.The trial was supported by funding from the Coalition for Epidemic Preparedness Innovations (CEPI) and was conducted at two sites in Australia."The Phase 1 data demonstrate that NVX-CoV2373 with our Matrix-M adjuvant is a well-tolerated COVID-19 vaccine with a robust immunogenicity profile," Gregory Glenn, President, Research and Development at Novavax, said in a statement."Using a stringent wild-type virus assay performed by investigators at the University of Maryland School of Medicine, NVX-CoV2373 elicited neutralising antibody titers greater than those observed in a pool of COVID-19 patients with clinically significant disease."NVX-CoV2373 is a vaccine candidate engineered from the genetic sequence of SARS-CoV-2, the virus that causes Covid-19 disease.It was created using Novavax' recombinant nanoparticle technology to generate antigen derived from the coronavirus spike (S) protein and contains Novavax' patented saponin-based Matrix-M adjuvant to enhance the immune response and stimulate high levels of neutralizing antibodies.The company said the data of the Phase-1 trial have been submitted for peer-review to a scientific journal and to an online preprint server at medRxiv.org.Novavax has become the third US company to release Phase-1 data of Covid-19 vaccines after Moderna and Pfizer.Novavax was awarded $1.6 billion by the US government as part of Operation Warp Speed (OWS), a program to deliver millions of doses of a safe, effective vaccine for Covid-19 to the US population.The funding is being used by Novavax to complete late-stage clinical development, including a pivotal Phase 3 clinical trial, establish large-scale manufacturing, and deliver 100 million doses of NVX-CoV2373 beginning as early as late 2020, the company said.