Pfizer bivalent COVID-19 vaccine for use as a booster dose in adults

On 27 October 2022, the Therapeutic Goods Administration (TGA) provisionally approved Pfizer’s bivalent COVID-19 vaccine, tozinameran and riltozinameran (COMIRNATY Original/Omicron BA.1) for use as a booster dose in adults 18 years and over. This is the second bivalent COVID-19 vaccine approved for use in Australia.

In making this regulatory decision, the TGA carefully considered data from an ongoing clinical study, which showed that the COMIRNATY Original/Omicron BA.1 vaccine elicited a superior neutralising antibody response against Omicron BA.1 strain and a similar response against the ancestral strain, after use as a booster dose compared with the original COMIRNATY vaccine.

Clinical studies assessing the activity of this vaccine against the BA.4/5 subvariants are ongoing, however initial results demonstrate that this vaccine produces neutralising antibodies against BA.4/5, though to a lesser extent than BA.1.

The TGA’s decision to provisionally approve the BA.1 bivalent vaccine was informed by expert advice from the Advisory Committee on Vaccines, an independent committee with expertise in scientific, medical and clinical fields and including consumer representation. The Australian Public Assessment Report (AusPAR) for this decision will be published in the coming days.

The Government's decision on the use of this vaccine in the Australian rollout will be informed by advice from the Australian Technical Advisory Group on Immunisation (ATAGI).

mRNA vaccines

COMIRNATY Original/Omicron BA.1 (tozinameran and riltozinameran) is the fourth mRNA vaccine to receive provisional approval in Australia. mRNA vaccines use a synthetic genetic code called RNA to give our cells instructions about how to make the coronavirus' unique spike protein. When our body has made the protein encoded by the mRNA vaccine, it then recognises the spike protein as being foreign and launches an immune response against it. The RNA from the vaccine does not change, or interact, with our DNA in any way.

Supporting regulatory documents

The provisional approval pathway provides a formal and transparent mechanism for registration of promising new medicines with preliminary clinical data.

The following regulatory documents are made available as part of this process:

• Product Information (PI)
• Consumer Medicine Information (CMI)
• COMIRNATY Original/Omicron BA.1 (tozinameran and riltozinameran) Decision Summary
  The decision summary provides a short overview of the TGA’s evaluation process leading to the registration of a new prescription medicine on the ARTG.
• AusPAR: tozinameran and riltozinameran - Booster dose in individuals aged 18 years and older
  An Australian Public Assessment Report (AusPAR) provides information about the evaluation of a prescription medicine and the considerations that led the TGA to approve or not approve a prescription medicine submission.
• Therapeutic Goods (Poisons Standard)(COVID-19 Vaccine - Pfizer) (Tozinameran and Riltozinameran) Labelling Exemption 2022