Moderna says its COVID-19 vaccine candidate is 94.5 percent effective

COVID-19 vaccine booster shots
Image source: FDA

Moderna, Inc. (NASDAQ: MRNA) announced that its COVI-19 vaccine candidate is 94.5% effective in preventing the disease based on the preliminary analysis of its Phase 3 trial of mRNA-1273.

The Massachusetts-based biotechnology company made the announcement a week after pharmaceutical giant Pfizer said its early analysis of its COVID-19 vaccine candidate showed an efficacy rate of more than 90%.

On Monday, Moderna said an independent, NIH-appointed Data Safety Monitoring Board (DSMB) disclosed that mRNA-1273 met the statistical criteria pre-specified in the study protocol for efficacy.

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Moderna said more than 30,000 people volunteered to participate in its Phase 3 trial, which the company conducted in collaboration with the National Institute of Allergy and Infectious Diseases (NIAID and the Biomedical Advanced Research and Development Authority (BARDA).

The DSMB based its initial analysis on 95 participants who received either a placebo or the COVID-19 vaccine candidate. Among those who received the vaccine, only five infections happened, which resulted in a point estimate of 94.5% efficacy rate.

The 95 COVID-19 participants included 15 older adults (ages 65+) and 20 participants identifying as being from diverse communities (including 12 Hispanic or LatinX, 4 Black or African Americans, 3 Asian Americans, and 1 multiracial).

In addition, Moderna said a review of solicited adverse events indicated that the participants tolerated adverse events from the COVID-19 vaccine.

The majority of adverse events include fatigue (9.7%), myalgia (8.9%), arthralgia (5.2%), headache (4.5%), pain (4.1%), and erythema/redness at the injection site (2.0%). The adverse events were mild to moderate and were generally short-lived.

In a statement, Moderna CEO Stéphane Bancel said, “This is a pivotal moment in the development of our COVID-19 vaccine candidate. Since early January, we have chased this virus with the intent to protect as many people around the world as possible. All along, we have known that each day matters. This positive interim analysis from our Phase 3 study has given us the first clinical validation that our vaccine can prevent COVID-19 disease, including severe disease.”

In the coming weeks, Moderna plans to file for an Emergency Use Authorization (EUA) with the U.S. Food and Drug Administration (FDA).

Moderna is part of the Trump Administration’s Operation Warp Speed.


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