A COVID-19 vaccine developed by UK pharmaceutical giant AstraZeneca and manufactured in Melbourne by CSL (ASX: CSL) will be progressively phased out of Australia's inoculation program from October.
Demand for the vaccine, which is now only recommended to be taken by Australians aged over 60 due to the risk - albeit still extremely low - of blood clotting in younger recipients, is also likely to drop according to the Federal Department of Health.
In addition, the Commonwealth Government expects additional supplies of Pfizer's mRNA COVID-19 vaccine will come online from September, alongside new supply of the jab developed by Moderna.
"Given the size of the Australian population over 60, it is assumed that demand for AstraZeneca doses will reduce in Horizon 2 [September 2021] and be met by Horizon 3 [October to December 2021]," says the Federal Government in a document called COVID Vaccination Allocation Horizons.
The document envisions three 'Horizons' to be met by the Commonwealth, starting in the July to August period, and ongoing until the end of the year.
'Horizon 1' envisions 2.2-2.6 million AstraZeneca doses to be administered per week from July to August, while 'Horizon 2' will see 880,000 to 1.2 million doses of the jab in arms every week in September.
By October the Government intends AstraZeneca vaccines will only be made available on request of the states. By that time, 1.7-2.3 million Pfizer vaccines and 430,000-615,000 Moderna doses will be administered per week to Australians.
Today, the Therapeutic Goods Administration (TGA) granted provisional determination to Moderna in relation to its vaccine, meaning the company is now eligible to apply for provisional registration of the jab in the Australian Register of Therapeutic Goods (ARTG).
"Provisional determination is the first step in the process," says the TGA.
"It is anticipated that Moderna will submit an application for provisional registration shortly. Importantly, registration and supply in Australia will only commence should the vaccine be approved as safe and effective by the TGA."
The Australian Government has secured 25 million doses of the Moderna COVID-19 vaccine, including the supply of 10 million doses in 2021 and of 15 million doses of Moderna's updated variant booster vaccine in 2022.
The updated rollout plan comes one week after new advice from the Australian Technical Advisory Group on Immunisation (ATAGI), recommending Australians aged under 60 to receive the Pfizer vaccine.
The advice came in response to analysis of case rates and demographics for a rare blood clot condition caused by the AstraZeneca COVID-19 vaccine.
"This remains a very rare but sometimes serious event. We're picking it up much more commonly than other countries because we're looking more fully," Chief Medical Officer Dr Paul Kelly said.
CSL shares were down 1.82 per cent at $288.90 each at 11am AEST.
Updated at 11am AEST on 24 June 2021.
Get our daily business news
Sign up to our free email news updates.