The federal government doesn't plan to use Johnson & Johnson's one-dose coronavirus shot in Australia's vaccine rollout.
The government was in talks with the pharmaceutical giant, which had asked for initial approval for its vaccine from Australia's medicine regulation.
But in a statement on Tuesday, a spokesperson for Health Minister Greg Hunt ruled out proceeding with the purchase for now.
"The [Johnson and Johnson] vaccine is an adenovirus vaccine, the same type of vaccine as the AstraZeneca vaccine," the statement read.
"The government does not intend to purchase any further adenovirus vaccines at this time."
It comes as the government attempts to ramp up its vaccine supply after receiving new medical advice about the AstraZeneca jab and its link to rare blood clots. Pfizer's shot is now preferred for Australians under the age of 50.
Most Australians were previously expected to receive the AstraZeneca shot, and the government has now given up on giving all adults their first vaccine doses by the end of October.
Department of Health Secretary Brendan Murphy last week said they had been in discussions with Johnson and Johnson about their vaccine, but its similarities to the AstraZeneca shot were a consideration.
"We have had the AstraZeneca vaccine which is an adenovirus vector vaccine, Johnson and Johnson is one too," Professor Murphy said.
"We still don't know what the cause of this adverse effect is, whether it relates to just this [AstraZeneca] vaccine or other adenoviruses, we have to wait and see."According to Johnson and Johnson, its vaccine was given emergency authorisation in the United States in February, "to prevent COVID-19 in individuals 18 years of age and older".
Health Secretary Dr Brendan Murphy and Prime Minister Scott Morrison at press conference at Parliament House, announcing approval of Pfizer coronavirus vaccine Source: AAP Image/Mick Tsikas
Nearly 6.5 million doses have since been administered as of 11 April, according to the US Centers for Disease Control and Prevention.
A 'recalibration' of vaccine targets
Australia currently has deals with AstraZeneca and Pfizer, with the government last week announcing it had secured another 20 million Pfizer doses.
It also has deals in place with Novavax, but the vaccine is yet to be approved for use.
In the wake of the updated AstraZeneca advice, Prime Minister Scott Morrison on Monday said time targets for the vaccine rollout were not practical as COVID "writes its own rules".
"You don't get to set the agenda," he said in a video posted to Facebook.
"Rather than set targets that can get knocked about by every to and fro of international supply chains and other disruptions that can occur, we are just getting on with it."Launching the first of a series of daily vaccination data updates to be published online, he said Australia's rate of 1.2 million to date was comparable to other major countries.
A medical worker fills a syringe with a dose of the Pfizer-BioNTech COVID-19 vaccine Source: Getty Images
Chief Medical Officer Paul Kelly said the updated AstraZeneca advice had forced a recalibration.
"I won't give a number or date but we absolutely committed to providing the vaccine to anyone, any adult Australian, who wants the vaccine as quickly as possible," he told reporters in Canberra.
Part of the recalibration will include changing where vaccines are available to better suit the new plan.
Professor Kelly said the initial phases of vaccinating quarantine, border, health, aged care and disability workers and residents were on track to be completed mid-year.
He said the rare side effect linked to the AstraZeneca showed there was some advantage to not being at the top of world rankings on vaccine rollout speed.
With reporting by AAP.