Early test results from a prospective novel coronavirus (COVID-19) vaccine could be a positive sign, researchers say, and Dr. Anthony Fauci calls the Phase 1 trial "very good news."

On Tuesday, The New England Journal of Medicine published findings from a recent round of one potential vaccine, mRNA-1273. According to the National Institutes of Health, the vaccine was "generally well tolerated and prompted neutralizing antibody activity in healthy adults."

The experimental vaccine is supported by NIH's National Institute of Allergy and Infectious Diseases and is being manufactured by the Massachusetts-based company, Moderna.

According to a press release, the vaccine is "designed to induce neutralizing antibodies directed at a portion of the coronavirus 'spike' protein, which the virus uses to bind to and enter human cells."

The recent findings include 45 participants between the ages of 18 and 55 in Seattle and Atlanta. Subjects received one to two injections of the vaccine at measurements of 25, 100, and 250 micrograms.

No major side effects were reported, though more than half of the participants noticed "fatigue, headache, chills, myalgia or pain at the injection site," according to a press release.

Phase 2 of the trials began in May, with a third round set for later this month. "We’re going to start the Phase 3 trial in the third or fourth week of July. That is going to take place over the rest of the summer and into the fall. If all goes well and there aren’t any unanticipated bumps in the road, hopefully, we should know whether the vaccine is safe and effective by the end of this calendar year, or the beginning of 2021," Dr. Fauci told InStyle.

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"These positive Phase 1 data are encouraging and represent an important step forward in the clinical development of mRNA-1273, our vaccine candidate against COVID-19, and we thank the NIH for their ongoing collaboration," said Stéphane Bancel, CEO of Moderna, in a press release.

Added Bancel: "We are committed to advancing the clinical development of mRNA-1273 as quickly and safely as possible while investing to scale up manufacturing so that we can help address this global health emergency."

Dr. Fauci pointed out that "the companies, both Moderna and other companies that are involved with the development of vaccines, promise that as we get into 2021, there’ll be an ample supply because they’re going to start making the doses imminently. By the beginning of the year we should have the first tens of millions and then hundreds of millions of doses. That being the case, I would think we could vaccinate a substantial portion of the population as we get into 2021 — if the vaccine is safe and effective."