A: The Moderna COVID-19 Vaccine is authorized to prevent coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in individuals 18 years of age and older.
For the December 2020 EUA for Moderna COVID-19 Vaccine, the FDA evaluated and analyzed the safety and effectiveness data from clinical trials conducted in tens of thousands of study participants and manufacturing information submitted by ModernaTX, Inc. The FDA has determined that the totality of the available data provides clear evidence that Moderna COVID-19 Vaccine may be effective in preventing COVID-19. Based on the scientific evidence available, the FDA concluded that the known and potential benefits of a two-dose primary series of the Moderna COVID-19 Vaccine outweigh the known and potential risks for people 18 years of age and older.
The FDA evaluated and analyzed the safety and effectiveness data from clinical trials conducted in tens of thousands of study participants and manufacturing information submitted by ModernaTX, Inc. The FDA has determined that the totality of the available data provides clear evidence that Moderna COVID-19 Vaccine may be effective in preventing COVID-19. The data also show that that the known and potential benefits outweigh the known and potential risks of the vaccine’s use in millions of people 18 years of age and older, including healthy individuals.
A: The data to support the December 2020 EUA include an analysis of 28,207 participants in the ongoing randomized, placebo-controlled U.S. study who did not have evidence of SARS-CoV-2 infection prior to the first dose of vaccine. Among these participants, 14,134 received the vaccine and 14,073 received placebo. The data showed a two-dose series of Moderna COVID-19 Vaccine was 94.1% effective in preventing COVID-19 disease among these clinical trial participants with 11 cases of COVID-19 in the vaccine group and 185 cases in the placebo group. At the time of the analysis of these 196 COVID-19 cases, 0 in the vaccine group and 30 in the placebo group were classified as severe. One severe case in the vaccine group was identified after the analysis (and not included among the 196 cases) and was awaiting confirmation at the time the FDA review was conducted.
A: Data are not yet available to inform about the duration of protection that the vaccine will provide.
A: It is not known if Moderna COVID-19 Vaccine protects against asymptomatic SARS-CoV-2 infection.
A: Yes. Among the participants in the study the FDA evaluated for the December 2020 authorization, overall, 20.5% of participants identified themselves as Hispanic or Latino, 10.2% as African American or Black, 4.6% as Asian, 0.8% as American Indian or Alaska Native, 0.2% as Native Hawaiian or other Pacific Islander, 2.1% identified their race as other, and 2.1% as multiracial. The demographic characteristics were similar among participants who received Moderna COVID-19 Vaccine and those who received placebo.
A: There is no scientific evidence to suggest that the vaccine could cause infertility in women. In addition, infertility is not known to occur as a result of natural COVID-19 disease, further demonstrating that immune responses to the virus, whether induced by infection or a vaccine, are not a cause of infertility. Reports on social media have falsely asserted that the vaccine could cause infertility in women and the FDA is concerned that this misinformation may cause women to avoid vaccination to prevent COVID-19, which is a potentially serious and life-threatening disease. SARS-CoV-2 is the virus that causes COVID-19. The symptoms of COVID-19 vary and are unpredictable; many people have no symptoms or only mild disease, while some have severe respiratory disease including pneumonia and acute respiratory distress syndrome (ARDS), leading to multi-organ failure and death. The Moderna COVID-19 vaccine is a mRNA vaccine. It contains a small piece of the SARS-CoV-2 virus’s genetic material that instructs cells in the body to make the virus’s distinctive “spike” protein. After a person is vaccinated, their body produces copies of the spike protein, which does not cause disease, and triggers the immune system to learn to react defensively, producing an immune response against SARS-CoV-2. Contrary to false reports on social media, this protein is not the same as any involved in formation of the placenta.
A: While there have been no specific studies in these groups, there is no contraindication to receipt of the vaccine for pregnant or breastfeeding women. Pregnant or breastfeeding women should discuss their options with their healthcare providers.
A: The available safety data to support the December 2020 EUA include an analysis of 30,351 participants enrolled in an ongoing randomized, placebo-controlled study conducted in the U.S. These participants, 15,185 of whom received the vaccine and 15,166 of whom received saline placebo, were followed for a median of more than two months after receiving the second dose.
The most commonly reported side effects were pain at the injection site, tiredness, headache, muscle pain, chills, joint pain, nausea and vomiting, swollen lymph nodes in the same arm of the injection and fever. Side effects typically started within two days of vaccination and resolved two or three days later.
Of note, more people experienced these side effects after the second dose than after the first dose, so it is important for vaccination providers and recipients to expect that there may be some side effects after either dose, but even more so after the second dose.
A: The FDA amended the emergency use authorization for Moderna COVID-19 Vaccine to allow for the use of a single booster dose administered at least 6 months after completing a primary series of the Moderna COVID-19 Vaccine to individuals 18 years of age and older.
Moderna COVID-19 Vaccine is administered as a two-dose primary series to individuals 18 years of age and older, as a third primary series dose for individuals 18 years of age and older who have been determined to have certain kinds of immunocompromise.
A single booster dose of the Moderna COVID-19 Vaccine may be administered to individuals 18 years of age and older as a heterologous booster dose following completion of primary vaccination with a different authorized or approved COVID-19 vaccine. The dosing interval for the heterologous booster dose is the same as that authorized for a booster dose of the vaccine used for primary vaccination.
A: The FDA evaluated safety and immune response data from a study in which a third dose of the Moderna COVID-19 Vaccine was administered to 60 individuals who had undergone a solid organ transplantation. The FDA determined that in the individuals studied, a third dose appears to be only moderately effective in increasing potentially protective antibodies. Based on available data, the FDA authorized a third primary series dose of the vaccine for individuals at least 18 years of age who have undergone solid organ transplantation, or who are diagnosed with conditions that are considered to have an equivalent level of immunocompromise.
To support the authorization for emergency use of a single booster dose of the Moderna COVID-19 Vaccine, the FDA analyzed safety and immune response data from a subset of participants from the original clinical studies who received a booster dose at least six months after their second dose. The immune responses of 149 participants, 18 years of age and older who received a booster dose at least 6 months after their second dose, were compared to the immune responses of 1,055 study participants 28 days after completing their two-dose series. The antibody response of the 149 participants against SARS-CoV-2 virus after a booster dose of the vaccine demonstrated a booster response.
Safety was evaluated in 171 participants 18 years of age and older who were followed for an average of approximately six months. The most commonly reported side effects by the clinical trial participants who received the booster dose of the vaccine were pain at the injection site, tiredness, headache, muscle and/or joint pain, chills, swollen lymph nodes in same arm as the injection, nausea and vomiting, and fever. Of note, swollen lymph nodes in the underarm were observed more frequently following the booster dose than after the primary two-dose series.
The authorization for emergency use of a single booster dose of Moderna COVID-19 Vaccine in individuals who completed primary vaccination with a different FDA-authorized or approved COVID-19 vaccine (heterologous booster dose) is based on the above-mentioned data as well as immunogenicity data from a clinical trial that evaluated a heterologous booster dose of the Moderna COVID-19 Vaccine. In this study, adults who had completed primary vaccination with a Moderna COVID-19 Vaccine (151 participants), a Janssen COVID-19 Vaccine (156 participants), or a Pfizer-BioNTech COVID-19 Vaccine (151 participants) received a booster dose of one of three vaccines: Moderna COVID-19 Vaccine, Janssen COVID-19 Vaccine, or Pfizer-BioNTech COVID-19 Vaccine. A booster response to the Moderna COVID-19 Vaccine was demonstrated regardless of primary vaccination.
The FDA requested an additional analysis from the vaccine manufacturer to compare the rates of COVID-19 accrued during the Delta variant surge among original clinical trial participants who completed a primary two-dose vaccination series early in the clinical trial to those who completed a 2-dose series later in the study. The analysis submitted by the company showed that during the study period of July and August 2021, the incidence of COVID-19 was higher among the participants who completed their primary vaccine series earlier, compared to participants who completed it later. This difference in incidence rates suggests waning of vaccine effectiveness over time.
Post-authorization safety surveillance data pertaining to myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the tissue surrounding the heart) demonstrate increased risks of myocarditis and pericarditis, particularly within 7 days following the second dose of the Moderna COVID-19 Vaccine, with the observed risk being higher in males under 40 years of age than in females or older males. The observed risk is highest in males 18 through 24 years of age.
The Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers) for the Moderna COVID-19 Vaccine includes a warning about the risks of myocarditis and pericarditis, and the Vaccine Information Fact Sheet for Recipients and Caregivers includes information about myocarditis and pericarditis. The Fact Sheet for Recipients and Caregivers notes that vaccine recipients should seek medical attention right away if they experience any of the following symptoms after vaccination:
• Chest pain
• Shortness of breath
• Feelings of having a fast-beating, fluttering, or pounding heart
A: An FDA analysis of the clinical trial safety database for hypersensitivity-related adverse events demonstrated a numerical imbalance across study groups, with 1.5% of vaccine recipients and 1.1% of placebo recipients reporting this type of event. There were no anaphylactic or severe hypersensitivity reactions reported following vaccination with Moderna COVID-19 Vaccine.
However, the Fact Sheet for Healthcare Providers Administering Vaccine and the Prescribing Information include the following information:
Do not administer the Moderna COVID-19 Vaccine to individuals with a known history of a severe allergic reaction (e.g., anaphylaxis) to a previous dose of the Moderna COVID-19 Vaccine or any component of the Moderna COVID-19 Vaccine (see Full EUA Prescribing Information).
Appropriate medical treatment to manage immediate allergic reactions must be immediately available in the event an acute anaphylactic reaction occurs following administration of the Moderna COVID-19 Vaccine.
This information is also consistent with the Prescribing Information for all vaccines intended to prevent infectious diseases.
The Fact Sheet for Healthcare Providers Administering Vaccine and the Prescribing Information direct the reader to the Centers for Disease Control and Prevention’s guidelines for monitoring for, and management of, allergic reactions following vaccination.
A: Serious adverse events were reported by 1.0% (147) of participants who received Moderna COVID-19 Vaccine and 1.0% (153) of participants who received placebo. These represented common medical events that occur in the general population at similar frequency.
Among Moderna COVID-19 Vaccine recipients, there were two serious adverse events of facial swelling that were likely related to vaccination, and also potentially related to these participants having previously received facial injections of dermal fillers (gel-like substances used for cosmetic purposes). There was one report of Bell’s palsy that was serious which occurred 32 days following receipt of vaccine. The information currently available is insufficient to determine a causal relationship with the vaccine. In addition, one Moderna COVID-19 Vaccine recipient reported a serious adverse event of difficult-to-control nausea and vomiting that occurred 1 day after vaccination. Although this vaccine recipient had a history of previous episodes of difficult-to-control nausea and vomiting, the FDA considers the post-vaccination episode as likely related to vaccination.
There were no other notable patterns or imbalances by age, race, ethnicity, or medical comorbidities, for specific categories of serious adverse events that would suggest a causal relationship to Moderna COVID-19 Vaccine.
A: Providers administering Moderna COVID-19 Vaccine must report to the Vaccine Adverse Event Reporting System (VAERS), and are encouraged to report to Moderna TX Inc., the following information associated with administration of the vaccine of which they become aware:
- Vaccine administration errors whether or not associated with an adverse event
- Serious adverse events (irrespective of attribution to vaccination)
- Cases of Multisystem Inflammatory Syndrome (MIS) in adults
- Cases of COVID-19 that result in hospitalization or death
A: The EUA requires vaccination providers, prior to administering the vaccine to an individual, to communicate to the recipient or their caregiver information consistent with the “Fact Sheet for Recipients and Caregivers,” and either to provide a copy of the Fact Sheet for Recipients and Caregivers or to direct the individual to the website, www.modernatx.com/covid19vaccine-eua, to obtain the fact sheet.
A: ModernaTX Inc. has a pharmacovigilance plan that was assessed by the FDA to monitor the safety of Moderna COVID-19 Vaccine. The pharmacovigilance plan includes a plan to complete longer-term safety follow-up for participants enrolled in ongoing clinical trials. The pharmacovigilance plan also includes other activities aimed at monitoring the safety of the vaccine and ensuring that any safety concerns are identified and evaluated in a timely manner.
Responsibility for additional post-authorization vaccine safety monitoring is shared primarily by the FDA and the U.S. Centers for Disease Control and Prevention, along with other agencies involved in healthcare delivery. Post-authorization safety monitoring during the COVID-19 pandemic vaccination program aims to continuously monitor the safety of COVID-19 vaccines to rapidly detect safety problems if they exist. There are multiple, complementary systems in place with validated analytic methods that can rapidly detect signals for possible vaccine safety problems. The U.S. government has a well-established post-authorization/post-approval vaccine safety monitoring infrastructure that has been scaled up to meet the needs of a large-scale COVID-19 vaccination program. The U.S. government – in partnership with health systems, academic centers, and private sector partners – are using multiple existing vaccine safety monitoring systems to monitor COVID-19 vaccines in the post-authorization/approval period. Some of these systems are the Vaccine Adverse Event Reporting System (VAERS), the Vaccine Safety Datalink (VSD), the Biologics Effectiveness and Safety (BEST) Initiative, and Medicare claims data.
A: Yes. Among the participants in the study that the FDA evaluated for the December 2020 Emergency Use Authorization of the Moderna COVID-19 Vaccine, only 2.2% of participants had evidence of prior infection at study enrollment. While relatively few confirmed COVID-19 cases occurred overall among participants with evidence of infection prior to vaccination, limited data suggest that previously infected individuals can be at risk of COVID-19 (i.e., reinfection) and may benefit from vaccination. Furthermore, available data suggest that the safety profile of the vaccine in previously infected individuals is just as favorable as in previously uninfected individuals.
A: Most vaccines that protect from viral illnesses also reduce transmission of the virus that causes the disease by those who are vaccinated. While it is hoped this will be the case, the scientific community does not yet know if Moderna COVID-19 Vaccine will reduce such transmission.
A: In a randomized, blinded clinical trial, participants are not aware of whether they received vaccine or placebo. Therefore, any mitigation efforts would have affected those who received vaccine and placebo equally. The relatively high number of COVID-19 cases occurring among placebo recipients suggests that any mitigation efforts among trial participants may not have been very effective at preventing COVID-19.
A: Additional data on vaccine effectiveness will be generated from further follow-up of participants in clinical studies already underway before the EUA was issued, plus studies conducted by the manufacturer or by the U.S. government evaluating effectiveness of the vaccine as used under the EUA.
A: The Moderna COVID-19 Vaccine is available in two multi-dose vials presentations. For extraction of only primary series doses (0.5mL each), one in which the maximum number of extractable doses is 11, with a range of 10-11 doses, and a second in which each vial contains a maximum of 15 doses, with a range of 13-15 doses that can potentially be extracted.
Depending on the type of syringes and needles used to extract each dose, there may not be sufficient volume to extract more than 10 doses from the vial containing a maximum of 11 doses or more than 13 doses from the vial containing a maximum of 15 doses.
When extracting only booster doses (0.25 mL each) or a combination of primary series and booster doses, the maximum number of doses that may be extracted from either vial presentation should not exceed 20 doses. The vial stopper is not to be punctured more than 20 times.
Primary series doses and booster doses may be extracted from either multi-dose vial presentation.
Because the Moderna COVID-19 Vaccine does not contain preservative, any further remaining product that does not constitute either a full primary series dose or a booster dose should not be pooled from multiple vials to create one full dose.
The Moderna COVID-19 Vaccine contains messenger RNA (mRNA) which is genetic material. The vaccine contains a synthetic piece of mRNA that instructs cells in the body to make the distinctive "spike" protein of the SARS-CoV-2 virus. When vaccinated, the body produces copies of the spike protein, which alone does not cause disease, and the immune system learns to react defensively, producing an immune response against SARS-CoV-2.
FDA scientists have expertise with this technology as it has been used to develop other preventive investigational vaccines that have been tested in human clinical trials. The FDA does not have specific safety concerns with a vaccine that utilizes this technology.
- Fact Sheet for Recipients and Caregivers
- Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers), which also includes Emergency Use Authorization (EUA) Prescribing Information
- FDA Decision Memorandum for use in individuals 18 years of age and older
- FDA Decision Memorandum for a third dose of the vaccine in certain immunocompromised individuals ages 18 years or older
- FDA Decision Memorandum for a single booster dose in certain individuals
- FDA Decision Memorandum for heterologous booster dose
- FDA Decision Memorandum for a single booster dose in individuals 18 years age and older and addendum
A: If safety or effectiveness concerns arise with a vaccine under EUA, the FDA has the authority to revoke the EUA. However, it is expected that the data supporting the EUA, together with those that will be collected during use of vaccine under EUA, and additional data collected from ongoing trials will be used to support licensure (approval) of a vaccine authorized under EUA.
A: The FDA believes it is important for clinical trials for other COVID-19 vaccines to continue or initiate. It is important to have a portfolio of COVID-19 vaccines available to be able to vaccinate our population.
A: FDA career scientists and physicians in the Center for Biologics Evaluation and Research made a determination that the emergency use authorization request met the criteria for issuing an EUA. The FDA’s former chief scientist, Rear Adm. Denise Hinton, signed the December 2020 letter of authorization.
A: The FDA embarked on an education campaign via social media, consumer content, media interviews, engagement with stakeholders and more to help the public understand our regulatory and scientific processes. These engagements will continue.