healthHealth and Medicine

Moderna Vaccine 100% Effective Against Severe Covid-19, Files For Emergency Use Authorization


Dr. Alfredo Carpineti

Senior Staff Writer & Space Correspondent

clockDec 1 2020, 16:53 UTC

Dimitris Barletis/

After the promising interim results published a few weeks ago, US biotech firm Moderna reports the final findings from the phase 3 trial of its Covid-19 vaccine. The overall efficacy of the vaccine is 94.1 percent (a slight change from the interim result) with an efficacy against severe Covid-19 of 100 percent.

The trial had 30,000 US participants, half of which were given two doses of the vaccine (four weeks apart) and the other half were given a placebo. During the trial, 196 people developed Covid-19, of which 185 were in the placebo group and 11 in the vaccine group. Thirty of the cases in the placebo group experienced severe Covid-19 symptoms and there were no severe cases in the vaccine group.


“This positive primary analysis confirms the ability of our vaccine to prevent Covid-19 disease with 94.1% efficacy and importantly, the ability to prevent severe Covid-19 disease. We believe that our vaccine will provide a new and powerful tool that may change the course of this pandemic and help prevent severe disease, hospitalizations and death,” Stéphane Bancel, chief executive officer of Moderna, said in a statement.

The company has submitted this data to the European Medicines Agency (EMA) and to the US Food and Drug Administration (FDA) for review and approval. The company expects an answer from the FDA during a meeting on December 17.

As seen in the interim data, the vaccine is well tolerated with no reports of significant side effects. The most common effects are fatigue, headaches, muscle pain, as well as pain and redness around the injection site. They are similar to the ones you might experience when receiving the flu vaccine.


The vaccine works by injecting a small fragment of the virus's genetic code, the mRNA, into the human body. This is used by the body's cells as instructions to produce a certain protein of the virus. When this protein enters the bloodstream, our immune system is activated and it learns how to get rid of the virus.

When the immune system encounters it again as an actual virus, it recognizes the virus and deals with it quickly. It is currently uncertain how long the immunity lasts.

For long-term storage, the Moderna Vaccine needs to be kept at a deep freezer temperature of -20°C/-4°F but can remain in a regular fridge for up to six months. Moderna believes that by the end of the month, it will have about 20 million doses of the vaccine available in the U.S. In 2021, the company expects to manufacture and ship between 500 million and 1 billion doses globally.

healthHealth and Medicine