Moderna's coronavirus vaccine is 94.1% effective in preventing COVID-19 and 100% effective in preventing severe illness, according to final results announced by the company on Monday (Nov. 30).
Moderna is also planning to file for an emergency use authorization (EUA) from the Food and Drug Administration (FDA) on Monday.
The final analysis was based on 196 confirmed cases of COVID-19 among participants in the trial, both those who received the placebo and those who received the vaccine. Of those cases, 185 were among those who were given a placebo and 11 were among those given the vaccine. These findings further confirm that Moderna's COVID-19 vaccine has a high efficacy rate; initial phase 3 analysis conducted on 95 participants had found that the vaccine was 94.5% effective, Live Science previously reported.
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In the final analysis, 30 of the participants developed severe disease (one of whom died) but all 30 of them were in the placebo group, suggesting that the vaccine is highly protective against severe disease. Moderna didn't report any significant safety concerns.
But the phase 3 trial is continuing and an independent Data Safety Monitoring Board (DSMB), appointed by the National Institutes of Health, will continue to gather safety data from the participants, according to the statement.
After seeing these results, "I allowed myself to cry for the first time," Dr. Tal Zaks, Moderna's chief medical officer, told The Associated Press. "We have already, just in the trial, have already saved lives. Just imagine the impact then multiplied to the people who can get this vaccine."
The FDA's Vaccines and Related Biological Products Advisory Committee will likely meet on Dec. 17 to discuss the safety and efficacy data from the trial, according to the statement. On Dec. 10, the committee will meet to discuss data from Pfizer and BioNTech's phase 3 clinical trial of its coronavirus vaccine, according to a statement from the FDA.
Moderna would be the second company to file for an EUA for their COVID-19 vaccine, following closely on the heels of Pfizer and BioNTech, who filed on Nov. 20. Moderna is planning to file for a similar emergency approval called a "conditional marketing authorization" from the European Medicines Agency (EMA) on Monday.
Both Pfizer and Moderna's vaccines are based on a genetic messenger called mRNA that instructs the body to develop spike proteins (the molecules the coronavirus uses to invade human cells). The immune system then learns to recognize the spike protein and builds up immune cells to fight the virus if the body is ever exposed. Both vaccines have now proved highly effective in preventing COVID-19.
Originally published on Live Science.
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Yasemin is a staff writer at Live Science, covering health, neuroscience and biology. Her work has appeared in Scientific American, Science and the San Jose Mercury News. She has a bachelor's degree in biomedical engineering from the University of Connecticut and a graduate certificate in science communication from the University of California, Santa Cruz.