TGA updates Pfizer vaccine side effect information

The revised Product Information follows 66 cases of suspected myocarditis and/or pericarditis recorded by the Therapeutic Goods Administration (TGA) up to 18 July, along with reports of similar cases overseas.
 
According to the TGA, these cases have primarily occurred within 14 days of vaccination, more often after the second vaccination, and more often in younger men.
 
The regulatory body also confirmed that Pfizer’s COMIRNATY vaccine is safe to administer to children as young as 12, but it is not clear when anyone from this age group will become eligible to receive doses as part of the rollout.
 
Professor Fiona Russell, a Principal Research Fellow focusing on infection and immunity at the Murdoch Children’s Research Institute, said data from international safety trials show that it is safe and effective in this age group.
 
‘This vaccine is routinely being given to all teenagers over 12 years old in the US and Canada, so millions of teenagers have already received the vaccine,’ she said.
 
‘Safety trials in young children [and] infants … are ongoing. If the data shows the vaccine is safe and effective in these age groups and populations, the vaccine rollout could be extended to these groups too.’
 
Meanwhile, Associate Professor Nicholas Wood, a Senior Lecturer in Paediatrics and Child Health at the Children’s Hospital, Westmead said safety surveillance systems will monitor myocarditis and pericarditis, and that guidelines for management are in development.
 
‘Vaccinating large numbers of adults will allow us to prevent deaths and serious illness, and therefore reduce the burden on health systems. That’s the primary goal,’ he said.
 
‘If we move to using the vaccine in younger adolescents then it makes sense to target higher-risk adolescents first.
 
‘Some countries, eg Israel, are wondering whether a single dose is sufficient for protection, especially as most cases of myocarditis are after dose two. [However], the US has been routinely giving two doses to 12–15-year-olds.’
 
Earlier on Friday, pregnant women were included in phase 1b of the rollout, more than a month after the Australian Technical Advisory Group on Immunisation (ATAGI) recommended that they be routinely offered the Pfizer vaccine at any stage of pregnancy.
 
Health authorities in New South Wales are also actively considering increasing the gap between administering the first and second doses of the Pfizer vaccine at state-run vaccination clinics in an effort to maximise current supplies.
 
However, it is not clear if or when general practices in NSW will be asked to adopt a similar regimen.
 
Earlier in the day, NSW Chief Health Officer Dr Kerry Chant flagged potential ‘hard choices’ related to prioritising Pfizer supply to expand the first dose program.
 
‘We may have to make decisions to delay the Pfizer interval to six weeks … to actually bring forward doses [for others],’ she said.
 
‘Can I just express the fact that some of those changes will impact on individuals. It may be that we need to cancel your bookings, but we have to make these hard choices if we are going to see these numbers stabilise first and then decline.’
 
The potential lengthening of the Pfizer regimen comes as fresh research from UK indicates an eight-week gap between doses could provide superior protection compared with the currently recommended three-week spacing.
 
Thursday was a record day overall for COVID vaccination in Australia, with nearly 200,000 doses administered, including more than 111,000 through primary care.
 
Despite the record day, there were still calls from within NSW to redistribute Pfizer doses from other states to help vaccinate essential workers in south-western Sydney aged 20–49, in an effort to reduce the transmission risk.
 
However, COVID-19 Taskforce Commander Lieutenant General John James Frewen indicated such an approach would be unlikely.
 
‘Vaccination underpins national resilience to COVID, but it is not the best way to deal with an immediate outbreak like this,’ he told a Senate COVID Committee hearing on Friday morning.
 
‘Our response is to go to the most vulnerable communities – we’ve done that … [and] we’ve spoken to some other high priority cohorts, but throwing vaccine at one geographic area does not give an immediate solution.’
 
Lieutnant General Frewen also reiterated that vaccines are allocated to states and territories on a per capita basis and that any reallocation of Pfizer requires ‘the concurrence of other jurisdictions’.

‘At the moment, we don’t have surplus Pfizer because the decision was to allocate all Pfizer out so the jurisdictions are responsible for managing their allocations of Pfizer with their particular priorities,’ he said.
 
‘I am not aware of NSW making a case for as to why other jurisdictions should prioritise their Pfizer to NSW.’
 
The Senate COVID committee also received an update on how many aged care and disability residents and workers have been vaccinated to date.
 
The latest figures show just over a quarter of workers in both sectors are fully vaccinated, despite them being a part of phase 1a:

• Aged care residents
  • First dose: 86.3%
  • Second dose: 82.3%
• Aged care workers
  • First dose: 47.2%
  • Second dose: 27.8%
• Disability residents
  • First dose: 57.7%
  • Second dose: 34.7%
• Disability workers
  • First dose: 50.9%
  • Second dose: 27.3%

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