WASHINGTON, April 6 (Xinhua) -- A second U.S. company is poised to begin safety test of a vaccine against COVID-19 on Monday.

Inovio Pharmaceuticals said Monday that the U.S. Food and Drug Administration (FDA) has accepted the company's Investigational New Drug (IND) application for INO-4800, its DNA vaccine candidate designed to prevent COVID-19 infection, paving the way for Phase 1 clinical testing in healthy volunteers beginning this week.

The Phase 1 study will enroll up to 40 healthy adult volunteers in Philadelphia and Kansas City, where screening of potential participants has already begun, said the company.

The study is a first step to see if the vaccine appears safe enough for larger tests needed to prove whether it will protect. Even if the research goes well, it is expected to take over a year before any vaccine could be widely available.

The first safety test in people of a different vaccine candidate, developed by the U.S. National Institutes of Health and Moderna Inc., began in Seattle last month.