For more information: www.cdc.gov/COVID19

Use of mRNA COVID-19 Vaccines:

Interim Clinical Considerations

Sarah Mbaeyi, MD MPH

December 19, 2020

ACIP COVID-19 Vaccines Work Group
 CDC clinical considerations for Pfizer-BioNTech

COVID-19 published:

– https://www.cdc.gov/vaccines/covid-19/info-byproduct/pfizer/clinical-considerations.html

 Clinical considerations will be updated to 

include both authorized mRNA vaccine products

–

–

Guidance harmonized across products with few 

differences (e.g., age indication, dosing schedule)

This presentation focuses on contraindications 

and precautions to vaccination

Clinical considerations for use of mRNA COVID-19 vaccines

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Contraindications and precautions to 

mRNA COVID-19 vaccines
 Prescribing information for both Pfizer-BioNTech and Moderna COVID-19 vaccines: 

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–

Severe allergic reaction (e.g., anaphylaxis) to any component of the vaccine is a 

contraindication to vaccination

Appropriate medical treatment used to manage immediate allergic reactions must be 

immediately available in the event an acute anaphylactic reaction occurs following 

administration of the vaccine

Contraindications to vaccination

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Ingredients* included in mRNA COVID-19 vaccines

*As reported in the prescribing information

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Description Pfizer-BioNTech Moderna

mRNA Nucleoside-modified mRNA encoding the viral 

spike (S) glycoprotein of SARS-CoV-2

Nucleoside-modified mRNA encoding the viral 

spike (S) glycoprotein of SARS-CoV-2

Lipids 2[(polyethylene glycol)-2000]-N,Nditetradecylacetamide

Polyethylene glycol (PEG) 2000 dimyristoyl

glycerol (DMG)

1,2-distearoyl-sn-glycero-3-phosphocholine 1,2-distearoyl-sn-glycero-3-phosphocholine

Cholesterol Cholesterol

(4-hydroxybutyl)azanediyl)bis(hexane-6,1-

diyl)bis(2-hexyldecanoate)

SM-102

Salts, sugars, 

buffers

Potassium chloride Tromethamine

Monobasic potassium phosphate Tromethamine hydrochloride

Sodium chloride Acetic acid

Dibasic sodium phosphate dihydrate Sodium acetate

Sucrose sucrose
Ingredients* included in mRNA COVID-19 vaccines

*As reported in the prescribing information

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Description Pfizer-BioNTech Moderna

mRNA Nucleoside-modified mRNA encoding the viral 

spike (S) glycoprotein of SARS-CoV-2

Nucleoside-modified mRNA encoding the viral 

spike (S) glycoprotein of SARS-CoV-2

Lipids 2[(polyethylene glycol)-2000]-N,Nditetradecylacetamide

Polyethylene glycol (PEG) 2000 dimyristoyl

glycerol (DMG)

1,2-distearoyl-sn-glycero-3-phosphocholine 1,2-distearoyl-sn-glycero-3-phosphocholine

Cholesterol Cholesterol

(4-hydroxybutyl)azanediyl)bis(hexane-6,1-

diyl)bis(2-hexyldecanoate)

SM-102

Salts, sugars, 

buffers

Potassium chloride Tromethamine

Monobasic potassium phosphate Tromethamine hydrochloride

Sodium chloride Acetic acid

Dibasic sodium phosphate dihydrate Sodium acetate

Sucrose sucrose
 History of severe allergic reaction (e.g., anaphylaxis) to any other vaccine or injectable 

therapy (e.g., intramuscular, intravenous, or subcutaneous) 

– Risk assessment should be conducted in persons who report history of severe allergic reaction 

(e.g., whether reaction required use of epinephrine [EpiPen®, etc.], resulted in hospitalization)

 These persons may still receive vaccination, but should be counseled about the unknown 

risks of developing a severe allergic reaction and balance these risks against the benefits 

of vaccination

Precautions to vaccination: Pfizer-BioNTech and Moderna

COVID-19 vaccines

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 Persons with the following allergies do not have a contraindication or precaution to 

vaccination:

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–

–

–

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History of food, pet, insect, venom, environmental, latex, or other allergies not related to 

vaccines or injectable therapies

History of allergy to oral medications (including the oral equivalent of an injectable medication)

Non-serious allergy to vaccines or other injectables (e.g., no anaphylaxis)

Family history of anaphylaxis

Any other history of anaphylaxis that is not related to a vaccine or injectable therapy

Allergies that do not constitute a contraindication or 

precaution to vaccination

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 Vaccine providers should observe patients after vaccination to monitor for the 

occurrence of immediate adverse reactions:

Observation period following vaccination

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Persons with a history of 

anaphylaxis (due to any cause)

All other persons

30 minutes 15 minutes
Algorithm for the triage of persons presenting for mRNA 

COVID-19 vaccine

10 https://www.cdc.gov/vaccines/covid-19/info-by-product/pfizer/clinical-considerations.html
Additional tools to identify 

persons with contraindications 

and precautions to vaccination

https://www.cdc.gov/vaccines/covid-19/downloads/pre-vaccination-screening-form.pdf 11
Fact sheets under development, including one 

tailored to long-term care facilities

Interim considerations:

Preparing for the potential 

management of anaphylaxis 

at COVID-19 vaccination sites

https://www.cdc.gov/vaccines/covid-19/info-by-product/pfizer/anaphylaxis-management.html 12
Key messages

Preparing for the potential management of anaphylaxis at COVID-19 vaccination sites

Early recognition of 

anaphylaxis symptoms

Prompt treatment with 

epinephrine

Activate emergency 

medical services

https://www.cdc.gov/vaccines/covid-19/info-by-product/pfizer/anaphylaxis-management.html 13
Recommended medications and supplies for the 

management of anaphylaxis at COVID-19 vaccination sties

*COVID-19 vaccination sites should have at least 3 doses of epinephrine on hand at any given time.

†Antihistamines may be given as adjunctive treatment and should not be used as initial or sole treatment for anaphylaxis. Additionally, caution should be used if oral 

medications are administered to persons with impending airway obstruction.

Should be available at all sites Include at sites where feasible

Epinephrine prefilled syringe or autoinjector* Pulse oximeter

H1 antihistamine (e.g., diphenhydramine)† Oxygen

Blood pressure cuff Bronchodilator (e.g., albuterol)

Stethoscope H2 antihistamine (e.g., famotidine, cimetidine)

Timing device to assess pulse Intravenous fluids

Intubation kit

Adult-sized pocket mask with one-way valve (also known 

as cardiopulmonary resuscitation (CPR) mask)

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Discussion
 Does ACIP agree with the proposed contraindications and precautions to vaccination?

 Are there any other sections of the clinical considerations that ACIP would like to 

discuss?

Discussion

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 Karen Broder

 Tom Clark

 Amanda Cohn

 Kathleen Dooling

 Julie Garon

 Susan Goldstein

 Rachel Gorwitz

 Joy Hsu

Acknowledgements

 Sarah Kidd

 Mona Marin

 Stacey Martin

 Dana Meaney-Delman

 Titilope Oduyebo

 Sara Oliver

 Heidi Soeters

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For more information, contact CDC

1-800-CDC-INFO (232-4636)

TTY: 1-888-232-6348 www.cdc.gov

The findings and conclusions in this report are those of the authors and do not necessarily represent the 

official position of the Centers for Disease Control and Prevention.

Thank you