ACV meeting statement, meeting 53, 4 June 2025

Section A: Premarket registration applications

The ACV was not asked to provide advice on a premarket registration application.

Section B: Post-market items

The ACV was asked to provide advice on one post-market or safety issue.

mRNA COVID-19 vaccines and transverse myelitis

The vaccines against COVID-19 that use the mRNA manufacturing platform are Comirnaty and Spikevax. Both the original formulations and more recent formulations were included in this review.

Transverse myelitis (TM) relates to inflammation of the spinal cord. Transverse myelitis can be caused by infections including viruses, and TM is also associated with autoimmune conditions.

The ACV advised that based on the available Australian pharmacovigilance data, published literature and data available in several international independent pharmacovigilance reporting systems, there is insufficient evidence to support transverse myelitis as being associated with either of the mRNA vaccines (Comirnaty and Spikevax, including strain updates).

The ACV noted that of the reports of myelitis or TM following mRNA COVID-19 vaccines made to the TGA:

• Many reports were incomplete and did not contain sufficient information to enable a full assessment.
• Some reports claimed an onset of TM on the same day or the day following vaccination, and some reports claimed an onset after the 42-day risk window. The association of TM with COVID-19 mRNA vaccines in these cases did not appear biologically plausible.
• Despite these limitations, the reported rate of TM following mRNA COVID-19 vaccines was extremely low and close to the expected background rate of TM in the general population.

For recent and any future reports, the ACV encouraged the TGA to liaise with the reporter to maximise the clinical and outcome information on the case. The ACV also encouraged analysis using the 1–42-day window of cases that strictly meet Brighton Collaboration case definition levels 1 to 3.

The ACV noted that the lower use of mRNA COVID-19 vaccines, and fewer first exposures to vaccine or virus, will reduce the power of any further analyses.

The safety of mRNA COVID-19 vaccines has been the subject of numerous publications by the TGA. The final COVID-19 vaccine safety report was published on 2 November 2023.

Further information

For further information on the Advisory Committee on Vaccines, please visit Advisory Committee on Vaccines (ACV) or contact the ACV Secretary by email: ACV@health.gov.au.