Novavax, which signed a memorandum of understanding in February to provide 1.1 billion doses in total, penned an advance purchase agreement with Covax for the first tranche.
They will be supplied, subject to regulatory approval, from the third quarter of 2021 onwards into 2022.
The Serum Institute of India plant is expected to manufacture and deliver the remaining 750 million Novavax doses.
SII is currently making AstraZeneca vaccine doses which are being blocked from export for Covax due to domestic demand, as the pandemic explodes in India.
Covax was set up to ensure poor countries have equitable access to vaccines to combat the coronavirus pandemic.
The facility is co-led by the World Health Organization (WHO), the Gavi vaccine alliance and the Coalition for Epidemic Preparedness Innovations.
CEPI invested nearly $400 million in Novavax in early 2020 to help get the vaccine off the ground.
“Today’s agreement with Novavax marks a major step towards Covax’s objective of building the world’s largest and most diverse portfolio of Covid-19 vaccines, and a major step towards our goal of delivering two billion doses of safe and effective vaccines in 2021,” said Gavi chief executive Seth Berkley.
96% efficacy – Novavax’s two-dose NVX-CoV2373 vaccine injects pieces of the coronavirus to evoke an immune response. It can be stored at regular refrigeration temperatures.
The vaccine is currently going through final-phase mass testing in the United States and Mexico — and separately in Britain, where trials showed it demonstrated 100 percent protection against developing severe disease and 96.4 percent efficacy against the original virus strain.
Once trials are completed, it must be approved by the WHO before it can be used by Covax.
Novavax was set to hold its first pre-submission meeting with the WHO on Friday — the first rung on the ladder towards authorisation by the UN health agency.
Novavax president Stanley Erck said Thursday’s deal was the culmination of an “urgent mission to deliver significant amounts of vaccines to all countries, regardless of income level”.
The agreement contains the opportunity for Covax to access potential future versions of the vaccine adapted to new variants.
“In addition, Novavax has agreed to provide additional doses in the event that Serum Institute cannot materially deliver expected vaccine doses to the Covax facility,” Gavi said.
53 mn doses shipped – Under Covax, the cost of vaccines for the 92 poorest participating economies is covered by donors.
Wealthier countries also buy vaccine supplies through the facility, taking advantage of its collective purchasing power.
Covax has signed deals of varying levels of commitment with AstraZeneca under license to SII and a plant in South Korea; Novavax; Pfizer-BioNTech; Johnson & Johnson; Sanofi-GSK, and Moderna.
Only AstraZeneca and some Pfizer jabs are currently flowing through the scheme, though the hold-up at SII has dented the programme.
The facility has so far shipped more than 53 million Covid-19 vaccine doses globally to 121 participating economies.
Earlier Thursday, Amnesty International, Human Rights Watch and the US consumer rights advocacy group Public Citizen urged Covax to publish its contracts with jab manufacturers, for the sake of transparency.
The groups said Covax had told them its contracts were commercially sensitive and protected under confidentiality obligations.