A: The available safety data to support the EUA in adolescents in this age group include 2,260 participants ages 12 through 15 years old enrolled in an ongoing randomized, placebo-controlled clinical trial in the United States. Of these, 1,131 adolescent participants received the vaccine and 1,129 received a saline placebo. More than half of the participants were followed for safety for at least two months following the second dose.

The most commonly reported side effects in the adolescent clinical trial participants, which typically lasted 1-3 days, were pain at the injection site, tiredness, headache, chills, muscle pain, fever and joint pain. With the exception of pain at the injection site, more adolescents reported 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. The side effects in adolescents were consistent with those reported in clinical trial participants 16 years of age and older. It is important to note that as a general matter, while some individuals experience side effects following any vaccination, not every individual’s experience will be the same and some people may not experience side effects.

The effectiveness data to support the EUA in adolescents in this age group is based on immunogenicity and an analysis of COVID-19 cases. The immune response to the vaccine in 190 participants 12 through 15 years of age was compared to the immune response of 170 participants 16 through 25 years of age. In this analysis the immune response of adolescents was non-inferior to (at least as good as) the immune response of the older participants. An analysis of cases of COVID-19 occurring among participants 12 through 15 years of age seven days after the second dose was also conducted. In this analysis, among participants without evidence of prior infection with SARS-CoV-2, no cases of COVID-19 occurred among 1,005 vaccine recipients and 16 cases of COVID-19 occurred among 978 placebo recipients; the vaccine was 100% effective in preventing COVID-19. At this time, there are limited data to address whether the vaccine can prevent transmission of the virus from person to person. In addition, at this time data are not available to determine how long the vaccine will provide protection.

A: The data to support the EUA of the Pfizer-BioNTech COVID-19 Vaccine include an analysis of 36,523 participants in the ongoing randomized, blinded, placebo-controlled international study, the majority of whom are U.S. participants, who completed the 2-dose vaccination regimen and did not have evidence of SARS-CoV-2 infection through 7 days after the second dose. Among these participants, 18,198 received the vaccine and 18,325 received saline placebo. The vaccine was 95 percent effective in preventing COVID-19 disease among these clinical trial participants with 8 COVID-19 cases in the vaccine group and 162 COVID-19 cases in the placebo group. Of these 170 COVID-19 cases, 1 in the vaccine group and 3 in the placebo group were classified as severe.

A: Data is not yet available to inform about the duration of protection that the vaccine will provide. 

A: The FDA updated the emergency use authorization for the Pfizer-BioNTech COVID-19 Vaccine to allow for the use of a single booster dose administered at least 6 months after completion of the vaccine primary series in individuals:

• 65 years of age and older
• 18 through 64 years of age at high risk of severe COVID-19
• 18 through 64 years of age whose frequent institutional or occupational exposure to SARS-CoV-2 puts them at high risk of serious complications of COVID-19 including severe COVID-19

The primary series for individuals 5 years of age and older consists of two doses.

The primary series for individuals 12 years of age and older who have been determined to have certain kinds of immunocompromise consists of three doses. People who are immunocompromised have a reduced ability to fight infections and diseases and are especially vulnerable to infections and disease, such as COVID-19.

The FDA evaluated information on the use of a third dose of the Pfizer-BioNTech COVID-19 Vaccine and determined that a third dose appears to be only moderately effective in increasing potentially protective antibodies in individuals 12 years of age and older who have undergone solid organ transplantation, and who are diagnosed with conditions that are considered to have an equivalent level of immunocompromise.

A: FDA analyzed safety and immune response data from a subset of participants from the original clinical trial of the Pfizer-BioNTech COVID-19 Vaccine. The immune responses of approximately 200 participants 18 through 55 years of age who received a single vaccine booster dose approximately 6 months after their second dose were assessed. The antibody response against a Wuhan-like SARS-CoV-2 virus one month after a booster dose of the vaccine compared to the response one month after the two-dose primary series in the same individuals demonstrated a booster response.

Safety was evaluated in 306 participants 18 through 55 years of age and 12 participants 65 years of age and older who were followed for an average of over two months. The most commonly reported side effects by the clinical trial participants who received the booster dose of the vaccine were pain, redness and swelling at the injection site, fatigue, headache, muscle or joint pain, and chills. Of note, swollen lymph nodes in the underarm were observed more frequently following the booster dose than after primary series doses.

A: An analysis compared the rates of COVID-19 accrued during the current Delta surge among original clinical trial participants who completed the two-dose vaccination series early in the clinical trial, to those who completed the two-dose series later in the study because they were originally randomized to the placebo group and received the vaccine later. The analysis showed that during the study period of July and August 2021, the incidence of COVID-19 was higher among the participants who completed their vaccine series earlier, compared to participants who completed the vaccine series later. FDA determined that the rate of breakthrough COVID-19 reported during this time period translates to a modest decrease in the efficacy of the vaccine among those vaccinated earlier, equivalent to one to five percent.

A: Yes. Available data suggest that previously infected individuals are at risk of COVID-19 (i.e., reinfection) and could benefit from vaccination.

A: It is not known if the vaccine protects against asymptomatic SARS-CoV-2 infection.

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 the Pfizer-BioNTech 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 infection rate among placebo recipients suggests that that any mitigation efforts among trial participants may not have been very effective.

A: Yes. Overall, among the total participants who received either Pfizer-BioNTech COVID-19 Vaccine or placebo, 9.1 percent were Black or African American, 28.0 percent were Hispanic/Latino, 4.3 percent were Asian, and 0.5 percent were American Indian/Alaska native.

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 potential benefits and risks of vaccination with their healthcare provider.

A: The available safety data to support the EUA include 37,586 of the participants enrolled in an ongoing randomized, placebo-controlled international study, the majority of whom are U.S. participants. These participants, 18,801 of whom received the vaccine and 18,785 of whom received saline placebo, were followed for a median of 2 months after receiving the 2nd dose. This is consistent with the recommendations set forth in the FDA’s October 2020 Guidance on Emergency Use Authorization for Vaccines to Prevent COVID-19.

The most commonly reported side effects were pain at the injection site, tiredness, headache, muscle pain, chills, joint pain, and fever. Side effects typically started within two days of vaccination and resolved 1-2 day 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 that there may be some side effects after either dose, but even more so after the second dose.

The FDA also evaluated additional safety data from the larger database that included participants enrolled later during the study who had shorter follow-up (the total database included 43,448 participants, 21,720 of whom received vaccine and 21,728 of whom received saline placebo). The FDA determined that the findings were similar to those in the population of participants with a median follow-up of 2 months after the 2nd dose.

A: Serious adverse events, while uncommon (<1.0%), were observed at slightly higher numerical rates in the vaccine study group compared to the saline placebo study group, both overall and for certain specific adverse events occurring in very small numbers. These represented common medical events that occur in the general population at similar frequency. Upon further review by the FDA, these imbalances do not raise a safety concern, nor do they suggest a causal relationship to vaccination for the vast majority of reported serious adverse events.

Serious adverse events considered by the FDA to be plausibly related to the vaccine or vaccination procedure were one case of shoulder injury at the vaccination site and one case of swollen lymph node in the armpit opposite the vaccination arm.

No safety concerns were identified in subgroup analyses by age, race, ethnicity, medical comorbidities, or prior SARS-CoV-2 infection. 

A. 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 Pfizer-BioNTech COVID-19 Vaccine, with the risk being higher in males under 40 years of age than in females or older males. The observed risk is highest in males 12 through 17 years of age.

The Fact Sheet for Healthcare Providers Administering Vaccine (Vaccination Providers) for the Pfizer-BioNTech COVID-19 Vaccine includes a warning about the risk of myocarditis and pericarditis, and the Vaccine Information Fact Sheet for Recipients and Caregivers include information about myocarditis and pericarditis. The Vaccine Information 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: Yes. Providers administering Pfizer-BioNTech COVID-19 Vaccine must report to the Vaccine Adverse Event Reporting System (VAERS) and to Pfizer the following information associated with 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
• Cases of COVID-19 that result in hospitalization or death

A: The EUA requires vaccination providers, prior to the individual receiving the vaccine, to communicate to the recipient or their caregiver information consistent with the “Vaccine Information Fact Sheet for Recipients and Caregivers,” and either to provide a copy of the Vaccine Information Fact Sheet for Recipients and Caregivers or to direct the individual to the CDC's website to obtain the fact sheet.

A: The Pfizer-BioNTech COVID-19 Vaccine has the same formulation as the FDA-approved Comirnaty COVID-19 vaccine and can be used interchangeably to provide the COVID-19 vaccination series without presenting any safety or effectiveness concerns. The products are legally distinct with certain differences that do not impact safety or effectiveness. 

There is no data available on the interchangeability of the Pfizer-BioNTech COVID-19 Vaccine with either Moderna COVID-19 Vaccine or Janssen COVID-19 Vaccine.

A: The Pfizer-BioNTech 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.

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 Pfizer-BioNTech COVID-19 vaccine is a mRNA vaccine. It contains a 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.

• Vaccine Information 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 16 years of age and older
• FDA Decision Memorandum for use in individuals 12 through 15 years of age
• FDA Decision Memorandum for a third dose of the vaccine in certain immunocompromised individuals age 12 years or older
• FDA Decision Memorandum for a single booster dose in certain individuals

A: The company has submitted a pharmacovigilance plan to the FDA to monitor the safety of the Pfizer-BioNTech COVID-19 Vaccine as it is used under EUA. 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 Pfizer-BioNTech COVID-19 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 (CDC), 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 – will use 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: 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 sufficient 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: Yes. After issuance of the EUA, clinical trial participants were unblinded in a phased manner over a period of months to offer the authorized Pfizer-BioNTech COVID-19 Vaccine to placebo participants. These participants were followed for safety outcomes. Overall, in blinded and unblinded follow-up, approximately 12,000 Pfizer-BioNTech COVID-19 Vaccine recipients have been followed for at least 6 months.

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 chief scientist, Rear Adm. Denise Hinton, signed the 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.

A: Yes, it is still important to continue to practice public health measures. The CDC recommends the following preventive actions: 

• Wash your hands often with plain soap and water. The CDC recommends washing your hands often with soap and water for at least 20 seconds, especially after you have been in a public place, or after blowing your nose, coughing, or sneezing. If soap and water are not available, the CDC recommends using an alcohol-based hand sanitizer that contains at least 60 percent alcohol. Learn more about safely using hand sanitizer.
• Cover your mouth and nose with a cloth face covering or non-surgical mask when around others.
• Avoid crowds and practice social distancing (stay at least 6 feet apart from others).