The Therapeutic Goods Administration (TGA) has provisionally approved the AstraZeneca COVID-19 vaccine for use in Australia, making it the second to secure regulatory approval in the country, after the Pfizer vaccine was given the green light last month.

In a statement, the TGA said it has approved the vaccine for use in people aged 18 and older. The vaccine should be administered in two separate doses, with the second able to be safely given between four to 12 weeks after the first.

Drawing on the advice of the TGA, the Australian Technical Advisory Group on Immunisation concluded that to create the best immune response, ensure the most effective clinical protection and maximise broader community coverage, doses of the vaccine should be administered 12 weeks apart.

The first priority groups in Australia will begin receiving the vaccine in early March.

Provisional approval of the vaccine is subject to strict conditions, including information being provided to the TGA on its longer-term efficacy and level of safety from ongoing clinical trial and post-market assessment.

While the AstraZeneca COVID-19 vaccine has been shown to prevent COVID-19, it is not yet known whether it stops transmission or asymptomatic disease, the statement said.

Further, while elderly patients over 65 have demonstrated a strong immune response to the vaccine in clinical trials, there was insufficient numbers of participants infected by COVID-19 to determine efficacy in this group. Reassuringly, there were no safety concerns reported among this group in clinical studies.

The TGA says the initial supply of the vaccine will be imported from overseas, yet it is anticipated that ongoing supply will be manufactured in Australia.

It will continue to actively monitor the vaccine in Australia and internationally and has pledged to take action if safety concerns are identified.

More information on Australia’s COVID-19 vaccine rollout is available on the Department of Health website