Patient Leaflet Updated 05-May-2026 | BioNTech - Pfizer
Comirnaty JN.1 3 micrograms/dose concentrate for dispersion for injection, 3-dose vial Infants and children 6 months to 4 years
Comirnaty JN.1 3 micrograms/dose concentrate for dispersion for injection, 3-dose vial
Infants and children 6 months to 4 years
COVID-19 mRNA Vaccine
bretovameran
▼This medicine is subject to additional monitoring. This will allow quick identification of new safety information. You can help by reporting any side effects your child may get. See the end of section 4 for how to report side effects.
1. What Comirnaty JN.1 is and what it is used for
2. What you need to know before your child receives Comirnaty JN.1
3. How Comirnaty JN.1 is given
4. Possible side effects
5. How to store Comirnaty JN.1
6. Contents of the pack and other information
Comirnaty JN.1 is a vaccine used for preventing COVID-19 caused by SARS-CoV-2.
Comirnaty JN.1 3 micrograms/dose concentrate for dispersion for injection, 3-dose vial is given to infants and children from 6 months to 4 years of age.
The vaccine causes the immune system (the body’s natural defences) to produce antibodies and blood cells that work against the virus, so giving protection against COVID-19.
As Comirnaty JN.1 does not contain the virus to produce immunity, it cannot give your child COVID-19.
The use of this vaccine should be in accordance with official recommendations.
Talk to your child’s doctor, pharmacist or nurse before your child is given the vaccine if your child:
There is an increased risk of myocarditis (inflammation of the heart muscle) and pericarditis (inflammation of the lining outside the heart) after vaccination with Comirnaty (see section 4). These conditions can develop within just a few days after vaccination and have primarily occurred within 14 days. They have been observed more often after the second vaccination, and more often in younger males. The risk of myocarditis and pericarditis seems lower in children ages 5 to 11 years compared with ages 12 to 17 years. Most cases of myocarditis and pericarditis recover. Some cases required intensive care support and fatal cases have been seen. Following vaccination, you should be alert to signs of myocarditis and pericarditis, such as breathlessness, palpitations and chest pain, and seek immediate medical attention should these occur.
As with any vaccine, Comirnaty JN.1 may not fully protect all those who receive it and it is not known how long your child will be protected.
The efficacy of Comirnaty may be lower in people who are immunocompromised. If your child is immunocompromised, he/she may receive additional doses of Comirnaty. In these cases, your child should continue to maintain physical precautions to help prevent COVID-19. In addition, your child’s close contacts should be vaccinated as appropriate. Discuss appropriate individual recommendations with your child’s doctor.
Comirnaty JN.1 3 micrograms/dose concentrate for dispersion for injection, 3-dose vial is not recommended for children aged 5 years to 11 years.
There are paediatric formulations available for children 5 to 11 years of age. For details, please refer to the Package Leaflet for other formulations.
The vaccine is not recommended for infants aged under 6 months.
Tell your child’s doctor or pharmacist if your child is using, has recently used or might use any other medicines or has recently received any other vaccine.
Comirnaty JN.1 3 micrograms/dose concentrate for dispersion for injection, 3-dose vial is not intended for individuals older than 5 years of age.
For details for use in individuals older than 5 years of age, please refer to the Package Leaflet for those formulations.
Some of the effects of vaccination mentioned in section 4 (Possible side effects) may temporarily affect your child’s ability to use machines or undertake activities such as cycling. Wait until these effects have worn off before resuming activities that require your child’s full attention.
If your infant is from 6 months to less than 12 months of age, he/she will be given Comirnaty JN.1 with a yellow cap after dilution as an injection of 0.3 mL into a muscle of the thigh. If your infant or child is 1 year of age or older, he/she will be given Comirnaty JN.1 with a yellow cap after dilution as an injection of 0.3 mL into a muscle of the thigh or into a muscle of the upper arm.
If your child has not completed a COVID-19 primary vaccination course or has not been infected by COVID-19 in the past, your child will receive a maximum of 3 injections (the total number of doses required as primary course). It is recommended to receive the second dose 3 weeks after the first dose followed by a third dose at least 8 weeks after the second dose to complete the primary course.
If your child has previously completed a COVID-19 primary vaccination course or has had COVID-19, your child will receive 1 injection. If your child was previously vaccinated with a COVID-19 vaccine, your child should not receive a dose of Comirnaty JN.1 until at least 3 months after the most recent dose.
If your child turns 5 years old between their doses in the primary course, he/she should complete the primary course at the same 3 micrograms dose level.
If your child is immunocompromised, he/she may receive additional doses of Comirnaty JN.1.
Your child may receive any previous or current Comirnaty vaccine for the primary course. Your child should not receive more than the total number of doses needed as primary course. Your child should only be administered the primary course once.
If you have any further questions on the use of Comirnaty JN.1, ask your child’s doctor, pharmacist or nurse.
Like all vaccines, Comirnaty JN.1 can cause side effects, although not everybody gets them.
Very common side effects: may affect more than 1 in 10 people
Common side effects: may affect up to 1 in 10 people
Uncommon side effects: may affect up to 1 in 100 people
Rare side effects: may affect up to 1 in 1 000 people
Very rare side effects: may affect up to 1 in 10 000 people
Not known (cannot be estimated from the available data)
If your child gets any side effects, talk to your child’s doctor, pharmacist or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via a Yellow card. Reporting forms and information can be found at https://coronavirus-yellowcard.mhra.gov.uk/ or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.
Keep this medicine out of the sight and reach of children.
The following information about storage, expiry and use and handling is intended for healthcare professionals.
Do not use this medicine after the expiry date which is stated on the carton and label after EXP. The expiry date refers to the last day of that month.
Store in freezer at -90 °C to -60 °C.
Store in the original package in order to protect from light.
The vaccine will be received frozen at -90 °C to -60 °C. Frozen vaccine can be stored either at -90 °C to -60 °C or 2 °C to 8 °C upon receipt.
When stored frozen at -90 °C to -60 °C, 10-vial packs of the vaccine can be thawed at 2 °C to 8 °C for 2 hours or individual vials can be thawed at room temperature (up to 30 °C) for 30 minutes.
Thawed (previously frozen) vials: Once removed from the freezer, the unopened vial may be stored and transported refrigerated at 2 °C to 8 °C for up to 10 weeks; not exceeding the printed expiry date (EXP). The outer carton should be marked with the new expiry date at 2 °C to 8 °C. Once thawed, the vaccine cannot be re-frozen.
Prior to use, the unopened vials can be stored for up to 12 hours at temperatures between 8 °C and 30 °C.
Thawed vials can be handled in room light conditions.
After dilution, store the vaccine at 2 °C to 30 °C and use within 12 hours, which includes up to 6 hours transportation time. Discard any unused vaccine.
Do not use this vaccine if you notice particulates in the dilution or discolouration.
Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.
The vaccine is a clear to slightly opalescent dispersion (pH: 6.9 - 7.9) provided in a multidose vial of 3 doses in a 2 mL clear vial (type I glass), with a rubber stopper and a yellow flip-off plastic cap with aluminium seal.
Pack size: 10 vials
For any information about this medicine, please contact: Medical Information,
This leaflet was last revised in 04/2026.
Ref: bCY (JN.1) 3 mcg Conc MDV 3 dose 7_0
2025-0099892, 2026-0102218
An der Goldgrube 12, Mainz, 55131, Germany
+49 (0) 6131 90 84 0
www.pfizermedicalinformation.co.uk
https://biontech.de/
+44 (0)1304 616161
