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NIH Record - 75th Anniversary - National Institutes of Health

NIH-Moderna Covid-19 Vaccine Shows Promising Interim Results

Plastic model of a coronavirus spike protein

3-D print of a spike protein of SARS-CoV-2—the virus that causes Covid-19—in front of a 3-D print of the virus particle

An independent data and safety monitoring board (DSMB) overseeing the phase 3 trial of the investigational Covid-19 vaccine known as mRNA-1273 shared its interim analysis on Nov. 15. This review of the data suggests that the vaccine is safe and effective at preventing symptomatic Covid-19 in adults. 

The analysis comprised 95 cases of symptomatic Covid-19 among volunteers. The DSMB reported that the candidate was safe and well-tolerated, noting a vaccine efficacy rate of 94.5 percent. The findings are statistically significant, meaning they are likely not due to chance. Ninety of the cases occurred in the placebo group and 5 occurred in the vaccinated group. There were 11 cases of severe Covid-19 out of the 95 total, all of which occurred in the placebo group.

The mRNA-1273 vaccine candidate was co-developed by the Cambridge, Mass.-based biotechnology company Moderna, Inc., and NIAID. It combines Moderna’s mRNA (messenger RNA) delivery platform with the stabilized SARS-CoV-2 spike immunogen developed by NIAID scientists.

The phase 3 vaccine efficacy trial, known as COVE, began under Operation Warp Speed, a multiagency collaboration led by HHS and the Department of Defense that aims to accelerate the development, manufacturing and distribution of medical countermeasures for Covid-19. 

More than 30,000 people at 100 clinical research sites in the U.S. are participating in the study, which launched in July. Recognizing the disproportionate impact of the epidemic on underrepresented minority populations, investigators worked with community engagement partners to enroll a diverse pool of participants. Among trial volunteers, 37 percent are from racial and ethnic minorities.

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