Vaccine Information: Pfizer-BioNTech Covid-19 Vaccine (Page 4 of 7)

6.2 Post Authorization Experience

The following adverse reactions have been identified during post authorization use of Pfizer-BioNTech COVID-19 Vaccine. Because these reactions are reported voluntarily, it is not always possible to reliably estimate their frequency or establish a causal relationship to vaccine exposure.

Cardiac Disorders: myocarditis, pericarditis

Gastrointestinal Disorders: diarrhea, vomiting

Immune System Disorders: severe allergic reactions, including anaphylaxis, and other hypersensitivity reactions (e.g., rash, pruritus, urticaria, angioedema)

Musculoskeletal and Connective Tissue Disorders: pain in extremity (arm)

Nervous System Disorders: syncope


See Overall Safety Summary (Section 6) for additional information.

The vaccination provider enrolled in the federal COVID-19 Vaccination Program is responsible for MANDATORY reporting of the listed events following Pfizer-BioNTech COVID-19 Vaccine to the Vaccine Adverse Event Reporting System (VAERS):

  • Vaccine administration errors whether or not associated with an adverse event
  • Serious adverse events* (irrespective of attribution to vaccination)
  • Cases of myocarditis
  • Cases of pericarditis
  • Cases of Multisystem Inflammatory Syndrome (MIS) in children and adults
  • Cases of COVID-19 that result in hospitalization or death

* Serious adverse events are defined as:

  • Death
  • A life-threatening adverse event
  • Inpatient hospitalization or prolongation of existing hospitalization
  • A persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions
  • A congenital anomaly/birth defect
  • An important medical event that based on appropriate medical judgement may jeopardize the individual and may require medical or surgical intervention to prevent 1 of the outcomes listed above

Instructions for Reporting to VAERS

The vaccination provider enrolled in the federal COVID-19 Vaccination Program should complete and submit a VAERS form to FDA using 1 of the following methods:

  • Complete and submit the report online:, or
  • If you are unable to submit this form electronically, you may fax it to VAERS at 1-877-721-0366. If you need additional help submitting a report you may call the VAERS toll-free information line at 1-800-822-7967 or send an email to

IMPORTANT: When reporting adverse events or vaccine administration errors to VAERS, please complete the entire form with detailed information. It is important that the information reported to FDA be as detailed and complete as possible. Information to include:

  • Patient demographics (e.g., patient name, date of birth)
  • Pertinent medical history
  • Pertinent details regarding admission and course of illness
  • Concomitant medications
  • Timing of adverse event(s) in relationship to administration of the Pfizer-BioNTech COVID-19 Vaccine
  • Pertinent laboratory and virology information
  • Outcome of the event and any additional follow-up information if it is available at the time of the VAERS report. Subsequent reporting of follow-up information should be completed if additional details become available.

The following steps are highlighted to provide the necessary information for safety tracking:

  1. In Box 17, provide information on Pfizer-BioNTech COVID-19 Vaccine and any other vaccines administered on the same day; and in Box 22, provide information on any other vaccines received within 1 month prior.
  2. In Box 18, description of the event:
    1. Write “Pfizer-BioNTech COVID-19 Vaccine EUA” as the first line.
    2. Provide a detailed report of vaccine administration error and/or adverse event. It is important to provide detailed information regarding the patient and adverse event/medication error for ongoing safety evaluation of this unapproved vaccine. Please see information to include listed above.
  3. Contact information:
    1. In Box 13, provide the name and contact information of the prescribing healthcare provider or institutional designee who is responsible for the report.
    2. In Box 14, provide the name and contact information of the best doctor/healthcare professional to contact about the adverse event.
    3. In Box 15, provide the address of the facility where vaccine was given (NOT the healthcare provider’s office address).

Other Reporting Instructions

Vaccination providers may report to VAERS other adverse events that are not required to be reported using the contact information above.

To the extent feasible, report adverse events to Pfizer Inc. using the contact information below or by providing a copy of the VAERS form to Pfizer Inc.

Website Fax number Telephone number 1-866-635-8337 1-800-438-1985

Vaccination providers administering COMIRNATY (COVID-19 Vaccine, mRNA) must adhere to the same reporting requirements.


There are no data to assess the concomitant administration of the Pfizer-BioNTech COVID-19 Vaccine with other vaccines.


11.1 Pregnancy

Risk Summary

All pregnancies have a risk of birth defect, loss, or other adverse outcomes. In the US general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Available data on Pfizer-BioNTech COVID-19 Vaccine administered to pregnant women are insufficient to inform vaccine-associated risks in pregnancy.

In a reproductive and developmental toxicity study, 0.06 mL of a vaccine formulation containing the same quantity of nucleoside-modified messenger ribonucleic acid (modRNA) (30 mcg) and other ingredients included in a single human dose of Pfizer-BioNTech COVID-19 Vaccine was administered to female rats by the intramuscular route on 4 occasions: 21 and 14 days prior to mating, and on gestation days 9 and 20. No vaccine-related adverse effects on female fertility, fetal development, or postnatal development were reported in the study.

11.2 Lactation

Risk Summary

Data are not available to assess the effects of Pfizer-BioNTech COVID-19 Vaccine on the breastfed infant or on milk production/excretion.

11.3 Pediatric Use

Pfizer-BioNTech COVID-19 Vaccine is authorized for use in individuals 6 months through 17 years of age. This authorization is based on safety and effectiveness data in this age group and adults.

Pfizer-BioNTech COVID-19 Vaccine is not authorized for use in individuals younger than 6 months of age.

11.4 Geriatric Use

Clinical studies of Pfizer-BioNTech COVID-19 Vaccine include participants 65 years of age and older who received the primary series and their data contributes to the overall assessment of safety and efficacy [see Overall Safety Summary (6.1) and Clinical Trial Results and Supporting Data for EUA (18.1)]. Of the total number of Pfizer-BioNTech COVID-19 Vaccine recipients in Study 2 (N=20,033), 21.4% (n=4,294) were 65 years of age and older and 4.3% (n=860) were 75 years of age and older.

11.5 Use in Immunocompromised

From an independent report (Kamar N, Abravanel F, Marion O, et al. Three doses of an mRNA Covid-19 vaccine in solid-organ transplant recipients. N Engl J Med) , safety and effectiveness of a third dose of the Pfizer-BioNTech COVID-19 vaccine have been evaluated in persons that received solid organ transplants. The administration of a third dose of vaccine appears to be only moderately effective in increasing potentially protective antibody titers. Patients should still be counselled to maintain physical precautions to help prevent COVID-19. In addition, close contacts of immunocompromised persons should be vaccinated as appropriate for their health status.


The Pfizer-BioNTech COVID-19 Vaccine is supplied as a frozen suspension in multiple dose vials with gray caps and labels with gray borders. Each 0.3 mL dose of the Pfizer-BioNTech COVID-19 Vaccine supplied in multiple dose vials with gray caps and labels with gray borders contains 30 mcg of a nucleoside-modified messenger RNA (modRNA) encoding the viral spike (S) glycoprotein of the SARS-CoV-2 Wuhan-Hu-1 strain.

Each 0.3 mL dose of the Pfizer-BioNTech COVID-19 Vaccine supplied in multiple dose vials with gray caps and labels with gray borders also includes the following ingredients: lipids (0.43 mg ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), 0.05 mg 2[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 0.09 mg 1,2-distearoyl-sn-glycero-3-phosphocholine, and 0.19 mg cholesterol), 0.06 mg tromethamine, 0.4 mg tromethamine hydrochloride, and 31 mg sucrose.

The Pfizer-BioNTech COVID-19 Vaccine does not contain preservative. The vial stoppers are not made with natural rubber latex.


14.1 Mechanism of Action

The modRNA in the Pfizer-BioNTech COVID-19 Vaccine is formulated in lipid particles, which enable delivery of the RNA into host cells to allow expression of the SARS-CoV-2 S antigen. The vaccine elicits an immune response to the S antigen, which protects against COVID-19.


18.1 Efficacy of Primary Series in Participants 16 Years of Age and Older

Study 2 is a multicenter, multinational, Phase 1/2/3, randomized, placebo-controlled, observer-blind, dose-finding, vaccine candidate-selection, and efficacy study in participants 12 years of age and older. Randomization was stratified by age: 12 through 15 years of age, 16 through 55 years of age, or 56 years of age and older, with a minimum of 40% of participants in the ≥56-year stratum. The study excluded participants who were immunocompromised and those who had previous clinical or microbiological diagnosis of COVID-19. Participants with preexisting stable disease, defined as disease not requiring significant change in therapy or hospitalization for worsening disease during the 6 weeks before enrollment, were included as were participants with known stable infection with human immunodeficiency virus (HIV), hepatitis C virus (HCV), or hepatitis B virus (HBV).

In the Phase 2/3 portion of Study 2, based on data accrued through November 14, 2020, approximately 44,000 participants 12 years of age and older were randomized equally and received 2 doses of Pfizer-BioNTech COVID-19 Vaccine (30 mcg modRNA) or placebo separated by 21 days. Participants are planned to be followed for up to 24 months, for assessments of safety and efficacy against COVID-19.

The population for the analysis of the primary efficacy endpoint included, 36,621 participants 12 years of age and older (18,242 in the Pfizer-BioNTech COVID-19 Vaccine group and 18,379 in the placebo group) who did not have evidence of prior infection with SARS-CoV-2 through 7 days after the second dose. Table 7 presents the specific demographic characteristics in the studied population.

Table 7: Demographics (population for the primary efficacy endpoint)*
Pfizer-BioNTech COVID-19 Vaccine (N=18,242)n (%) Placebo(N=18,379)n (%)
All eligible randomized participants who receive all vaccination(s) as randomized within the predefined window, have no other important protocol deviations as determined by the clinician, and have no evidence of SARS-CoV-2 infection prior to 7 days after Dose 2.
Pfizer-BioNTech COVID-19 Vaccine (30 mcg modRNA).
100 participants 12 through 15 years of age with limited follow-up in the randomized population received at least 1 dose (49 in the vaccine group and 51 in the placebo group). Some of these participants were included in the efficacy evaluation depending on the population analyzed. They contributed to exposure information but with no confirmed COVID-19 cases, and did not affect efficacy conclusions.
Includes multiracial and not reported.
Number of participants who have 1 or more comorbidities that increase the risk of severe COVID-19 disease
  • Chronic lung disease (e.g., emphysema and chronic bronchitis, idiopathic pulmonary fibrosis, and cystic fibrosis) or moderate to severe asthma
  • Significant cardiac disease (e.g., heart failure, coronary artery disease, congenital heart disease, cardiomyopathies, and pulmonary hypertension)
  • Obesity (body mass index ≥30 kg/m2)
  • Diabetes (Type 1, Type 2 or gestational)
  • Liver disease
  • Human Immunodeficiency Virus (HIV) infection (not included in the efficacy evaluation)
Male 9318 (51.1) 9225 (50.2)
Female 8924 (48.9) 9154 (49.8)
Age (years)
Mean (SD) 50.6 (15.70) 50.4 (15.81)
Median 52.0 52.0
Min, max (12, 89) (12, 91)
Age group
≥12 through 15 years 46 (0.3) 42 (0.2)
≥16 through 17 years 66 (0.4) 68 (0.4)
≥16 through 64 years 14,216 (77.9) 14,299 (77.8)
≥65 through 74 years 3176 (17.4) 3226 (17.6)
≥75 years 804 (4.4) 812 (4.4)
White 15,110 (82.8) 15,301 (83.3)
Black or African American 1617 (8.9) 1617 (8.8)
American Indian or Alaska Native 118 (0.6) 106 (0.6)
Asian 815 (4.5) 810 (4.4)
Native Hawaiian or other Pacific Islander 48 (0.3) 29 (0.2)
Other § 534 (2.9) 516 (2.8)
Hispanic or Latino 4886 (26.8) 4857 (26.4)
Not Hispanic or Latino 13,253 (72.7) 13,412 (73.0)
Not reported 103 (0.6) 110 (0.6)
Yes 8432 (46.2) 8450 (46.0)
No 9810 (53.8) 9929 (54.0)

The population in the primary efficacy analysis included all participants 12 years of age and older who had been enrolled from July 27, 2020, and followed for the development of COVID-19 through November 14, 2020. Participants 18 through 55 years of age and 56 years of age and older began enrollment from July 27, 2020, 16 through 17 years of age began enrollment from September 16, 2020, and 12 through 15 years of age began enrollment from October 15, 2020.

The vaccine efficacy information is presented in Table 8.

Table 8: Vaccine Efficacy – First COVID-19 Occurrence From 7 Days After Dose 2, by Age Subgroup – Participants Without Evidence of Infection and Participants With or Without Evidence of Infection Prior to 7 Days After Dose 2 – Evaluable Efficacy (7 Days) Population
Note: Confirmed cases were determined by Reverse Transcription-Polymerase Chain Reaction (RT-PCR) and at least 1 symptom consistent with COVID-19 (symptoms included: fever; new or increased cough; new or increased shortness of breath; chills; new or increased muscle pain; new loss of taste or smell; sore throat; diarrhea; vomiting).
Participants who had no evidence of past SARS-CoV-2 infection (i.e., N-binding antibody [serum] negative at Visit 1 and SARS-CoV-2 not detected by NAAT [nasal swab] at Visits 1 and 2), and had negative NAAT (nasal swab) at any unscheduled visit prior to 7 days after Dose 2 were included in the analysis.
Pfizer-BioNTech COVID-19 Vaccine (30 mcg modRNA).
N = Number of participants in the specified group.
n1 = Number of participants meeting the endpoint definition.
Total surveillance time in 1000 person-years for the given endpoint across all participants within each group at risk for the endpoint. Time period for COVID-19 case accrual is from 7 days after Dose 2 to the end of the surveillance period.
n2 = Number of participants at risk for the endpoint.
No confirmed cases were identified in adolescents 12 through 15 years of age.
Credible interval for vaccine efficacy (VE) was calculated using a beta-binomial model with a beta (0.700102, 1) prior for θ=r(1-VE)/(1+r(1-VE)), where r is the ratio of surveillance time in the active vaccine group over that in the placebo group.
Confidence interval (CI) for vaccine efficacy is derived based on the Clopper and Pearson method adjusted to the surveillance time.
First COVID-19 occurrence from 7 days after Dose 2 in participants without evidence of prior SARS-CoV-2 infection *
Subgroup Pfizer-BioNTech COVID-19 Vaccine N =18,198Casesn1§Surveillance Time (n2#) PlaceboN =18,325Casesn1§Surveillance Time (n2#) Vaccine Efficacy %(95% CI)
All subjects Þ 82.214 (17,411) 1622.222 (17,511) 95.0(90.3, 97.6)ß
16 through 64 years 71.706 (13,549) 1431.710 (13,618) 95.1(89.6, 98.1)à
65 years and older 10.508 (3848) 190.511 (3880) 94.7(66.7, 99.9)à
First COVID-19 occurrence from 7 days after Dose 2 in participants with or without evidence of prior SARS-CoV-2 infection
Subgroup Pfizer-BioNTech COVID-19 Vaccine N =19,965Casesn1§Surveillance Time (n2#) PlaceboN =20,172 Casesn1§Surveillance Time (n2#) Vaccine Efficacy %(95% CI)
All subjects Þ 92.332 (18,559) 1692.345 (18,708) 94.6(89.9, 97.3)ß
16 through 64 years 81.802 (14,501) 1501.814 (14,627) 94.6(89.1, 97.7)à
65 years and older 10.530 (4044) 190.532 (4067) 94.7(66.8, 99.9)à provides trustworthy package insert and label information about marketed drugs and vaccines as submitted by manufacturers to the U.S. Food and Drug Administration. Package information is not reviewed or updated separately by Every individual vaccine label and package insert entry contains a unique identifier which can be used to secure further details directly from the U.S. National Institutes of Health and/or the FDA.

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