Comirnaty

Pronunciation: Cuh-mir-na-tee
Generic name: COVID-19 Vaccine, mRNA
Brand name: Comirnaty 2024-2025 Formula
Dosage form: suspension for intramuscular injection
Drug class: Viral vaccines

Medically reviewed by Carmen Pope, BPharm. Last updated on Sep 3, 2024.

What is Comirnaty?

Comirnaty (made by Pfizer-BioNTech) is an mRNA COVID-19 vaccine that may help your body develop immunity to SARS-CoV-2, the virus that causes COVID-19.

Given as a single dose for most people.
Updated for 2024-2025 to cover Omicron KP.2.

Comirnaty does not contain any live virus particles, including those of SARS-CoV-2, the virus that causes COVID-19. It cannot give you COVID-19, although it may not protect everyone who receives the vaccine.

Comirnaty is an mRNA vaccine, which means its mechanism of action is to use messenger RNA (mRNA) to provide instructions for making the spike protein of the COVID-19 virus. Your body then recognizes this spike protein as foreign and produces antibodies and T cells to attack it. This helps your body prepare to fight off the real COVID-19 virus if you're exposed to it.

Comirnaty is an FDA-approved vaccine for adults and adolescents aged 12 years and older.

Pfizer-BioNTech COVID-19 vaccine has Emergency Use Authorization (EUA) for children aged 6 months through 11 years.

Comirnaty side effects

The most common side effects of Comirnaty include:

Pain where you get the injection
Tiredness or fatigue
Headache
Chills
Muscle pain
Joint pain
Fever
Injection site swelling
Injection site redness.

Other side effects reported include nausea, feeling unwell, swollen lymph nodes (lymphadenopathy), decreased appetite, diarrhea, vomiting, dizziness, and fainting in association with the injection of the vaccine.

Serious side effects and warnings

There is a remote chance that Comirnaty could cause a severe allergic reaction. A severe allergic reaction would usually occur within a few minutes to 1 hour after getting a dose. For this reason, your vaccination provider may ask you to stay at the place where you received your vaccine for monitoring after vaccination. Signs of a severe allergic reaction can include:

Difficulty breathing
Swelling of your face and throat
A fast heartbeat
A bad rash all over your body
Dizziness and weakness.

Myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart) have occurred in some people who have received mRNA COVID-19 vaccines, including Comirnaty and Pfizer-BioNTech COVID-19 vaccines. Myocarditis and pericarditis following Comirnaty have occurred most commonly in adolescent males 12 through 17 years of age. In most of these individuals, symptoms began within a few days following vaccination. The chance of having this occur is very low. You should seek medical attention right away if you or your child have any of the following symptoms after receiving the vaccine, particularly during the 2 weeks after receiving a dose of the vaccine:

Chest pain
Shortness of breath
Feelings of having a fast-beating, fluttering, or pounding heart.

These may not be all the possible side effects of Comirnaty. Ask your healthcare provider about any side effects that concern you. Report vaccine side effects to the FDA/CDC Vaccine Adverse Event Reporting System (VAERS). The VAERS toll-free number is 1-800-822-7967 or report online to https://vaers.hhs.gov/reportevent.html.

In addition, you can report side effects to Pfizer Inc. at 1-800-438-1985 or www.pfizersafetyreporting.com.

Before receiving Comirnaty

You should not get Comirnaty if you have had a severe allergic reaction to a previous dose of Comirnaty, the Pfizer-BioNTech COVID-19 vaccine, or any of the components in the vaccine (see "Ingredients' below).

Tell your vaccination provider about all of your medical conditions, including if you:

have any allergies
have had myocarditis (inflammation of the heart muscle) or pericarditis (inflammation of the lining outside the heart)
have a fever
have a bleeding disorder or are on a blood thinner
are immunocompromised or are on a medicine that affects your immune system
are pregnant or plan to become pregnant
are breastfeeding
have received another COVID-19 vaccine
have ever fainted in association with an injection.

Safety and effectiveness have not been established in children less than 12 years of age. Evidence from clinical studies strongly suggests that a single dose of Comirnaty is ineffective in individuals younger than 6 months of age.

Pregnancy

Comirnaty is generally considered safe for use during pregnancy and major health organizations, including the CDC, ACOG, and AAP, recommend COVID-19 vaccination for pregnant individuals, which includes Comirnaty.

Data from pregnant people who have received mRNA COVID-19 vaccines, including Comirnaty, have not identified any safety concerns for pregnant people or their babies. The vaccine can be administered at any time during pregnancy. Pregnant individuals are at increased risk for severe illness from COVID-19 compared to non-pregnant people and vaccination during pregnancy can help protect both the mother and the baby. Antibodies generated by the vaccine can pass to the fetus, potentially providing some protection to the newborn.

Breastfeeding

It is not known whether Comirnaty is excreted in human milk or its effects on the breastfed infant or milk production/excretion. Consider the benefits versus the risks.

How is Comirnaty given?

Comirnaty is given to you as an injection into a muscle, usually the deltoid muscle of the upper arm.

1 injection is usually given. The amount of liquid Comirnaty contains is 0.3 mL.

What other drugs will affect Comirnaty?

Tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Tell your healthcare provider if you take:

a blood thinner, such as warfarin
a medicine that affects your immune system, such as cyclosporine

Also, tell your healthcare provider if you have received any other COVID-19 vaccines.

Comirnaty ingredients

Active: messenger RNA (mRNA)

Other ingredients: lipids (((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate), 2 [(polyethylene glycol)-2000]-N,N-ditetradecylacetamide, 1,2-distearoyl-sn-glycero-3-phosphocholine, and cholesterol), tromethamine, tromethamine hydrochloride, and sucrose.

Comirnaty does not contain preservatives.
The vial stoppers are not made with natural rubber latex.
The prefilled syringe tip cap and plunger stopper are not made with natural rubber latex.