Early Data from Phase 3 Trial Show Moderna’s Coronavirus Vaccine Is 94.5% Effective

Moderna, Inc. (Nasdaq: MRNA), a biotechnology company pioneering messenger RNA (mRNA) therapeutics and vaccines to create a new generation of transformative medicines for patients, today announced that the independent, NIH-appointed Data Safety Monitoring Board (DSMB) for the Phase 3 study of mRNA-1273, its vaccine candidate against COVID-19, has informed Moderna that the trial has met the statistical criteria pre-specified in the study protocol for efficacy, with a vaccine efficacy of 94.5%. This study, known as the COVE study, enrolled more than 30,000 participants in the U.S. and is being conducted in collaboration with the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health (NIH), and the Biomedical Advanced Research and Development Authority (BARDA), part of the Office of the Assistant Secretary for Preparedness and Response at the U.S. Department of Health and Human Services.

Pfizer and Moderna each announced the findings in news releases, not in peer-reviewed scientific journals, and the companies have not yet disclosed the detailed data that would allow outside experts to evaluate their claims. Therefore, the results cannot be considered conclusive. The studies are continuing, and the figures on effectiveness may change.

Researchers say the positive results from Pfizer and Moderna bode well for other vaccines because all of the candidates being tested aim at the same target — the so-called spike protein on the coronavirus that it uses to invade human cells. The results also align well with antibody-based therapeutics such as Eli Lilly’s antibody cocktail recently approved by the FDA for distribution.

Dr. Bloom said that the success of the two vaccines meant that measures of immunity used in earlier phases of the studies—participants’ antibody levels—-were reliable, and that other companies could use those measures as proof of effectiveness to shorten the testing and approval process for their vaccines.

It will be important to determine whether the vaccines work equally well in older and younger people, experts say. Researchers also want to know if the vaccines prevent people from spreading the virus — an ideal result that could help quash the pandemic.

Another big unknown is how long the immunity provided by the vaccines will last.

Further Reading:

Moderna Announcement on Preliminary Results of Phase 3 COVE Study

Moderna Covid-19 Vaccine Information Center

NEJM Paper: An mRNA Vaccine against SARS-CoV-2 — Preliminary Report

Early Data from Phase 3 Trial Show Moderna’s Coronavirus Vaccine Is 94.5% Effective
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