The Government is expected to make an announcement on Wednesday afternoon on if the Pfizer/BioNTech vaccine has been approved for use in New Zealand.
Medsafe met with the Medicine Assessment Advisory Committee on Tuesday to receive final advice about whether the vaccine is safe and effective, and if they should give provisional consent.
The decision is expected to be announced by Prime Minister Jacinda Ardern at a press conference around 2pm.
Vaccinologist Helen Petousis-Harris said she expects the vaccine will get the go-ahead.
"I would be surprised if it was a 'no'. I think the roads are pointing to 'yes', the data looks good," she told The AM Show on Wednesday.
Petousis-Harris said Medsafe and the committee has taken the time to complete the vaccine approval process properly, including analysing the clinical trials and data from countries which had already been using the vaccine.
"[They've been looking for] anything wrong with it," she said. "They really assess the safety data closely, line-by-line. They get thousands of pages to trawl through. Also, the manufacturing process, are they happy with that? Along with a whole lot of other stuff."
Millions of people around the world have already received COVID-19 vaccines with more than 50 countries already administering doses.
According to BBC, 9.2 million people have now received a first dose of a vaccine in the UK, and more than 490,000 people have had a second.3
In the United States, about 26 million Americans had received at least one dose the US Centres for Disease Control and Prevention said on Sunday.
Petousis-Harris told The AM Show she didn't think being behind other country's vaccine rollouts was a negative, as it gave the Government more time to assess its effectiveness.
"I think around 100 million people have already had a COVID vaccine… we are going to be a part of that very soon," she said.
"We can look back and say there were 100 million doses, what's been happening with those? How's that gone? I think we can get a lot more confidence from that."
Once a vaccine is approved, it is set to be New Zealand's largest immunisation roll-out ever.
"We have never before attempted an immunisation programme of this scale, cost or complexity," the Government said in a statement last week.
"We’re aiming to vaccinate as many New Zealanders as possible – so that’s potentially 5 million people."
Cabinet has already set aside just under NZ$1 billion (NZ$983.7 million) from the COVID-19 Response and Recovery Fund to secure access to COVID-19 vaccines.
They are also planning to train an extra 2000-3000 extra full-time vaccinators to help administer the vaccine.