Updated Dec. 23, 2020LanguagesPrint
General information
Name: mRNA-1273
Manufacturer: ModernaTX, Inc.
Type of vaccine: mRNA
Learn more about how COVID-19 vaccines work and get a better understanding of COVID-19 mRNA vaccines.
Number of shots: 2 shots, one month (28 days) apart
How given: Shot in the muscle of the upper arm
Does not contain:
- Eggs
- Preservatives
- Latex
For a full list of ingredients, see Moderna’s COVID-19 Vaccine Fact Sheet for Recipients and Caregiversexternal icon.Who should get vaccinated
- The Moderna vaccine is recommended for people aged 18 years and older. Learn more about how CDC is making COVID-19 vaccine recommendations and who should be vaccinated first when supplies are limited.
Who should not get vaccinated
- If you have had a severe allergic reaction—also known as anaphylaxis—to any ingredient in the Moderna vaccine, you should not get vaccinated.* Learn more about COVID-19 vaccines and rare severe allergic reactions.
*If you have had a severe allergic reaction to other vaccines or injectable therapies, ask your doctor if you should get the Moderna vaccine. Your doctor will help you decide if it is safe for you to get the Moderna vaccine.
Side effects and safety information
Most common side effects
In the arm where you got the shot:
- Pain
- Swelling
- Redness
Throughout the rest of your body:
- Chills
- Tiredness
- Headache
These side effects usually start within a day or two of getting the vaccine. They might feel like flu symptoms and might even affect your ability to do daily activities, but they should go away in a few days. Get tips on what to expect after getting vaccinated.
Summary of safety data
- In clinical trials, reactogenicity symptoms (side effects that happen within 7 days of getting vaccinated) were common but were mostly mild to moderate.
- Side effects (such as fever, chills, tiredness, and headache) throughout the body were more common after the second dose of the vaccine.
- Most side effects were mild to moderate. However, a small number of people had severe side effects that affected their ability to do daily activities.
- CDC will continue to provide updates as we learn more about the safety of the Moderna vaccine in real-world conditions. Learn more about vaccine safety monitoring after a vaccine is authorized or approved for use.
Learn more about safety and reactogenicity data from the clinical trials.
Information on how well the vaccine works
- Based on evidence from clinical trials, the Moderna vaccine was 94.1% effective at preventing laboratory-confirmed COVID-19 illness in people who received two doses who had no evidence of being previously infected.
- The vaccine appeared to have high effectiveness in clinical trials (efficacy) among people of diverse age, sex, race, and ethnicity categories and among persons with underlying medical conditions.
- Although few people in the clinical trials were admitted to the hospital, this happened less often in the people who got the Moderna vaccine compared to people who got the saline placebo.
- CDC will continue to provide updates as we learn more about how well the Moderna vaccine works in real-world conditions.
Demographic information from clinical trials
Clinical trials for the Moderna vaccine included people from the following racial and ethnic categories:
- 79.4% White
- 20% Hispanic/Latino
- 9.7% African American
- 4.7% Asian
- <3% other races/ethnicities
Age and sex breakdown:
- 52.6% male
- 47.4% female
- 25.3% 65 years and older
Most people who participated in the trials (82%) were considered to have an occupational risk of exposure, with 25.4% of them being healthcare workers.
Among people who participated in the clinical trials, 22.3% had at least one high-risk condition, which included lung disease, heart disease, obesity, diabetes, liver disease, or HIV infection. Four percent (4%) of participants had two or more high-risk conditions.
Learn more about demographic information for people who participated in the trials.external icon
