(Adds details on agreement, background)
Jan 7 (Reuters) - The government of Australia has signed an advanced agreement to purchase 51 million doses of Novavax Inc's NVAX.O experimental COVID-19 vaccine, the company disclosed in a regulatory filing on Thursday.
Australia will have the option to purchase up to an additional 10 million doses, with the initial doses expected to be delivered by mid-2021, the company said. (https:// started a large late-stage study of the vaccine in the United States in December after delaying it twice due to issues in scaling up the manufacturing process. company lags behind other drugmakers in the global race for a COVID-19 vaccine, with shots from Pfizer (NYSE:PFE) PFE.N , Moderna MRNA.O and AstraZeneca authorized in some countries.
Novavax in November signed an agreement in principle with the Australian government for a supply of 40 million doses of the vaccine and Thursday's deal replaces the earlier agreement. (https://reut.rs/3bmlNya)
Australia has seen a rise in COVID-19 cases since the middle of December and new measures to combat the disease have kicked in. (https://reut.rs/3npMLYe)
The government will support Novavax to seek approval from the health regulator of Australia for its COVID-19 vaccine candidate, the company said.
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