Managing risks associated with the introduction of the Comirnaty vaccine for children 5 to 11 years old

Emma Kirk, Specialist Pharmacist - Lead Medication Safety, Medicines Use and Safety TeamPublished Last updated See all updates

Characteristics of Pfizer's Comirnaty vaccines for adults/adolescents and children differ. Teams must understand the differences to ensure safety.

Taking action to manage risks

Products

From January 2022, two Comirnaty vaccines are available:

  • Comirnaty (30 micrograms/dose) concentrate for Adults and Adolescents
  • Comirnaty (10 micrograms/dose) concentrate for Children 5 to 11 years

Risks and actions

The introduction of the new Comirnaty (10 micrograms/dose) concentrate for Children 5 to 11 years vaccine increases operational complexity and introduces risks for sites handling both vaccines. These are particularly relevant where staff have previously been familiar only with the characteristics of the adult vaccine.

Teams should consider implementing processes to ensure all staff involved are aware of the differences between the products and are able to handle each appropriately. Teams should pay particular attention to understanding the differences between products for: dilution; dosage; doses per vial; and storage. A comparison of these is presented below to support local processes.

Dilution differences

The vaccines are diluted with different volumes of the same diluent i.e. sodium chloride 0.9%.

Children 5 to 11 years

1.3ml of sodium chloride 0.9% is required for dilution for Comirnaty for Children 5 to 11 years.

Adults and Adolescents

1.8ml of sodium chloride 0.9% is required for dilution for Comirnaty for Adults and Adolescents.

Dosage differences

The dose and dosage volumes are different.

Children 5 to 11 years

10 micrograms in 0.2ml is the dose required for Comirnaty for Children 5 to 11 years.

Adults and Adolescents

30 micrograms in 0.3ml is the dose required for Comirnaty for Adults and Adolescents.

Doses per vial differences

The vaccine vials contain different numbers of doses.

Children 5 to 11 years

10 doses are present in the vial for Comirnaty for Children 5 to 11 years.

Adults and Adolescents

6 doses are present in the vial for Comirnaty for Adults and Adolescents.

Storage differences

The storage characteristics of the vaccines differ for ultra-low temperature and refrigerated storage times, and for diluted and undiluted vaccine.

Children 5 to 11 years

ULT shelf life

If delivered at ULT (-90°C to -60°C) Comirnaty for Children 5 to 11 years vaccine can be stored in a ULT freezer  up to 9 months.

Refrigerated shelf life

After thawing at 2°C to 8°C or if delivered thawed, the undiluted Comirnaty for Children 5 to 11 years vaccine can be stored in a refrigerator (2°C to 8°C) for up to 10 weeks.

Room temperature storage before dilution

The undiluted Comirnaty for Children 5 to 11 years vaccine can be stored at room temperature (8°C to 30°C) for up to 12 hours before dilution.

Room temperature storage after dilution

The Comirnaty for Children 5 to 11 years vaccine should be used as soon as possible after dilution and within 12 hours stored at room temperature (8°C to 30°C).

Adults and Adolescents

ULT shelf life

If delivered at ULT (-90°C to -60°C) the Comirnaty for Adults and Adolescents vaccine can be stored in a ULT freezer for up to 9 months.

Refrigerated shelf life

After thawing at 2°C to 8°C or if delivered thawed, the Comirnaty for Adults and Adolescents vaccine can be stored in a refrigerator (2°C to 8°C) for up to 31 days.

Room temperature storage time before dilution

The Comirnaty for Adults and Adolescents vaccine can be stored at room temperature (8°C to 30°C) for up to 2 hours before dilution.

Room temperature storage time after dilution

The Comirnaty for Adults and Adolescents vaccine should be used as soon as possible after dilution and within 6 hours stored at room temperature (8°C to 30°C).

Transportation Differences

Children 5 to 11 years

The thawed, packed Comirnaty concentrate for Children 5-11 years may be transported unlimited times during its 10 week post-thaw shelf life.

The Comirnaty for Children 5 to 11 years vaccine must not be transported once diluted.

Adults and Adolescents

The thawed, packed Comirnaty concentrate for adults and adolescents may be transported for up to 12 hours during its 31 day post-thaw shelf life with no limit to the number of journeys. It must take into account any journeys the vaccine may have already taken in its thawed state.

The Comirnaty for Adults and Adolescents vaccine may be transported once diluted in certain specific circumstances.

Presentation and formulation differences

The vaccines differ in a number of other presentation and formulation characteristics.

Children 5 to 11 years

Presentation and formulation characteristics for Comirnaty for Children 5 to 11 years.

Presentation

The vial has an orange cap and band on label.

Potassium content

The vaccine does not contain potassium.

Sodium content

The vaccine does not contain sodium.

Excipients

The vaccine contains:

  • ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate) (ALC-0315)
  • 2-[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide (ALC-0159)
  • Cholesterol
  • Trometamol
  • Trometamol hydrochloride
  • Sucrose
  • Water for injections

Pack size

The pack contains 10 vials.

Adults and Adolescents

Presentation and formulation characteristics for Comirnaty for Adults and Adolescents.

Presentation

The vial has a purple cap and band on label

Potassium content

The vaccine contains <1 mmol.

Sodium content

The vaccine contains <1 mmol.

Excipients

The vaccine contains:

  • ((4-hydroxybutyl)azanediyl)bis(hexane-6,1-diyl)bis(2-hexyldecanoate) (ALC-0315)
  • 2-[(polyethylene glycol)-2000]-N,N-ditetradecylacetamide (ALC-0159)
  • 1,2-Distearoyl-sn-glycero-3-phosphocholine (DSPC)
  • Cholesterol
  • Potassium chloride
  • Potassium dihydrogen phosphate
  • Sodium chloride
  • Disodium phosphate dihydrate
  • Sucrose
  • Water for injections
  • Sodium hydroxide
  • Hydrochloric acid

Pack size

The pack contains 195 vials.

Polyethylene Glycol Content

Both vaccines contain polyethylene glycol (PEG – also known as macrogols).

Further information

Good governance guidance when handling multiple COVID-19 vaccines

2 March 2021Six practice points will ensure good governance: right patient, right vaccine, right dose, right route, right time and right records

Information and guidance specific to COVID-19 Vaccine Pfizer-BioNTech

Resources covering pharmaceutical aspects of the vaccination programme specific to COVID-19 Vaccine Pfizer-BioNTech

Change history

  1. ULT shelf life increased to 9 months for Comirnaty for Children 5 to 11 years vaccine
  1. Further information regarding transportation of concentrate added
  1. Published