Moderna's vaccine spurred immune system response to coronavirus

Healthy volunteers who took Moderna's coronavirus vaccine candidate appeared to generate an immune system response to the virus, and there were "no trial-limiting safety concerns," according to a new study published in the New England Journal of Medicine.

Why it matters: The phase one trial is still small and does not definitively determine how effective the vaccine is. But Anthony Fauci of the National Institutes of Health, which is running the trial, told the Wall Street Journal that these data make it "pretty clear that this vaccine is capable of inducing quite good [levels] of neutralizing antibodies."

Between the lines: The study builds on Moderna's early self-reported results from May.

• The vaccine cleared the safety bar, as adverse events were mild and mostly limited to fatigue, chills and pain where the shot was injected.
• The trial also indicated an immune system response was greatest after the second shot.

What's next: A phase two trial of Moderna's vaccine is ongoing, and a larger phase three trial that will rigorously test the effectiveness of Moderna's vaccine will start later this month, with the hope of getting data in the fall.

• Pfizer and BioNTech, which are using similar technology as Moderna, are advancing their vaccine candidate on a similar timeline.

Go deeper: Moderna reveals the limits of making a coronavirus vaccine