Coronavirus: TGA approves AstraZeneca vaccine for all ages

The second COVID-19 vaccine to get the green light from the health regulator comes with good news for older Australians.

The Oxford-AstraZeneca COVID-19 vaccine. Picture: AFP

Australia’s medical regulator insists the AstraZeneca vaccine will prove to be highly effective in the elderly as it declined to follow the example of a host of European countries that have refused to approve the vaccine’s use in those aged over 65.

The approval of the AstraZeneca vaccine by the Therapeutic Goods Administration came after a clinical evaluator assessing the vaccine expressed “significant concern” about the robustness of the efficacy data from phase III clinical trials.

The TGA’s Public Assessment Report for the vaccine reveals the clinical evaluator questioned aspects of the clinical trials including that the study design was “not entirely fit for purpose to evaluate efficacy in high-risk groups”, contained insufficient data about dosing, and that a number of patients were not included in the final efficacy analysis.

The clinical evaluator noted that the primary efficacy demonstrated was sufficient for European Medicines Agency and Food and Drug Administration requirements., but said “there needs to be consideration as towhether the efficacy demonstrated is sufficient for use in the Australian context where COVID-19 is less prevalent.”

“Although it is understandable that the clinical development plan needed to evolve in the context of the pandemic and as more knowledge about the vaccine and COVID-19 became available, there are significant concerns about the robustness of the data,” the clinical evaluator said.

Oxford University scientists and AstraZeneca have acknolwedged their trial design changed as the study was in train, and results were complicated by the fact that a sub-group in the trial accidentally received only a halfdose.

The TGA said on Tuesday that it was satisfied the vaccine was safe and effective, however it issued a statement as to the limited nature of the data regarding efficacy in the elderly.

TGA head John Skerritt said immunogenicity data indicated the elderly would have a strong immune response to the vaccine.

He said on the balance of the evidence, there was no reason to limit the vaccine to use in certain age groups.

Hundreds of thousands of doses of the AstraZeneca vaccine are set to arrive in Australia in early March after the TGA approved the vaccine for use in all ages.

The efficacy of the vaccine will be maximised by a dosage schedule of 12 weeks between the first and second jabs, which has been shown in clinical trials to result in an efficacy rate of 82.4 per cent.

AstraZeneca said it had unpublished “encouraging data” on the vaccine’s ability to interrupt the transmission of COVID-19.

Scott Morrison said the regulatory approval of the Astra-Zeneca vaccine had paved the way for all Australians to be vaccinated against the coronavirus, with 50 million doses being locally manufactured by CSL. The announcement came as the government revealed research conducted by the Federal health department which showed 71 per cent of Australians would have a COVID-19 vaccine by October.

“It will be provided free to Australians and it means that Australia now has two safe and effective COVID-19 vaccines available,” the Prime Minister said.

The Pfizer vaccine was approved in January. More than 140,000 doses of that vaccine arrived in Australia on Monday and is now being batch-tested by the TGA ahead of first vaccinations beginning on Monday.

The TGA said the AstraZeneca vaccine was safe and effective for use in all ages. It declined to follow several European countries in limiting the vaccine’s use to those aged under 65., saying immunogenicity data indicated the vaccine induced a strong immune response in the elderly.

It recommended the vaccine be given to the elderly on a “case by case basis”.