Photo: CJ Gunther/EPA-EFE

UPI.com

U.S. regulators have cleared a potential COVID-19 vaccine developed by Moderna Therapeutics for a second phase of clinical trials, officials said Thursday.

The Food and Drug Administration said it's completed its phase-one safety review for Moderna's mRNA-1273 vaccine candidate and has authorized the start of a second stage study, the company said in a quarterly financial statement.

The study is set to begin shortly while protocols for a pivotal phase-three study are expected to begin in early summer, Moderna CEO Stephane Bancel said.

"Moderna is now preparing to potentially have its first [vaccine] approved as soon as 2021," he said.

The company said it's ramping up its manufacturing capacity so the vaccine can be distributed on a wide scale if it ultimately receives final approval.

The Massachusetts-based company was given $483 million in federal funding last month to develop a coronavirus vaccine. The money supports large-scale distribution and late-stage clinical development programs.

Moderna's mRNA-1273 candidate is one of several now in the clinical trial stage. Pfizer announced Tuesday it's begun testing its candidate vaccine to human subjects in the United States. Other clinical-stage candidates are being developed in the United States, China and Britain.