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According to the Phase 3 trial results published on December 30, the recently authorized COVID-19 vaccine developed by Moderna and the National Institute of Allergy and Infectious Diseases (NIAID) was effective 94.1%. The New England Journal of Medicine.
No cases of severe COVID-19 occurred among participants who received the vaccine, known as mRNA-1273, and there were no safety concerns.
The U.S. Food and Drug Administration issued an emergency use authorization on Dec. 18 for the vaccine, a lipid-nanoparticle-encapsulated mRNA vaccine that expresses the pre-fusion-stabilized vein glycoprotein.
The trial began in July, enrolling 30,420 adults in the United States. Volunteers were randomly assigned in a 1: 1 ratio to receive two doses of the vaccine or two shots of saline with 28 days apart. The average age of the participants was 51 years.
A total of 196 cases of symptomatic COVID-19 occurred at least 14 days after participants received their second shot – 185 cases in the placebo group and 11 in the vaccine group.
In a secondary analysis that included cases that occurred at least 14 days after the first admission, vaccine efficacy was 95.2%, said author Lindsey R. Baden, MD, of Brigham and Women’s Hospital, Boston. Massachusetts, and colleagues reported.
About half of the participants who received mRNA-1273 had moderate to severe side effects after the second dose, such as fatigue, muscle aches, joint pain, and headaches. Most side effects are resolved within 20 days.
Future studies
Future studies will assess the effect of the vaccine on infectivity.
Both the Moderna vaccine and the Pfizer BioNTech vaccine “begin to protect recipients approximately ten days after the first dose, with maximum protection after the second dose,” Barton F. Haynes, MD, said in an accompanying editorial .
That both have effective vaccine efficiencies of 94% to 95% – and that both vaccines have been developed and tested in less than a year – is extraordinary scientific and medical triumph, “said Haynes, director of the Duke Human Vaccine Institute, Durham, said North Carolina.
“mRNA technology could radically change the vaccine design for future viral outbreaks,” he said.
Continued safety monitoring and analysis of virus escape against protective immune responses will be important, Haynes added.
Subgroup analyzes by age, gender, race / ethnicity, and risk for severe COVID-19 showed that ‘effectiveness is generally maintained’. tweeted Medscape Editor-in-Chief Eric Topol, Managing Director, Leader of the Scripps Translational Science Institute in La Jolla, California.
https://twitter.com/EricTopol/status/1344410761712398336
Topol highlights the absence of severe COVID-19 among participants who received the vaccine. All 30 participants in the trial who developed severe COVID-19 were in the placebo group. One death among the participants was attributed to COVID-19.
The study was supported by the Biomedical Advanced Research and Development Authority and the NIAID. Baden is deputy editor at the The New England Journal of Medicine and received NIH grants during the study. Baden works with federal agencies, companies and foundations on clinical trials against HIV and COVID-19. Some co-authors are employees of Moderna or disclose links with pharmaceutical companies or grants from foundations and federal agencies. Haynes has owned Moderna shares at one point in the past year, has received grants from the NIH outside of the work submitted, and patents pending in connection with the development of COVID-19 vaccine. He has collaborated with Baden on research projects for HIV vaccine.
N Engl J Med. Published online on December 30, 2020. Full text
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