Johnson & Johnson has asked US health regulators to authorize its single-dose Covid-19 vaccine for emergency use, and it will apply to European authorities in coming weeks.
The drugmaker's application to the US Food and Drug Administration (FDA) follows its January 29 report in which it said the vaccine had a 66pc rate of preventing infections in its large global trial.
The FDA said on Thursday evening that it has scheduled a meeting of its Vaccines and Related Biological Products Advisory Committee on February 26, to discuss the company's request for emergency use authorization.
Vaccines from Pfizer Inc/BioNTech and Moderna were authorized a day after such a meeting.
J&J's single-shot vaccine could help boost supply and simplify the US immunization campaign, amid concerns of fresh surges due to the more contagious UK coronavirus variant and the potential of lower vaccine efficacy against a variant that first emerged in South Africa.
Unlike the two currently authorized vaccines from Pfizer/BioNTech and Moderna, J&J's does not require a second shot or need to be shipped frozen.
After the company's application, regulators will need time to analyze the data and an advisory committee must meet. The company's chief scientific officer, Paul Stoffels, said last month J&J was on track to roll out the vaccine in March.
"Upon authorization of our investigational Covid-19 vaccine for emergency use, we are ready to begin shipping," Stoffels said in a statement announcing the application.
J&J said it had rolling submissions with several global health agencies and would submit a Conditional Marketing Authorization Application with the European Medicines Agency in the coming weeks.
J&J's application raised hopes for fighting a pandemic that has claimed more than 451,145 American lives and over 2,271,152 worldwide.
Shares of Johnson & Johnson rose about 1% in extended trading on Thursday, while Moderna was down 0.7pc and Pfizer stock was little changed.
The United States has agreed to pay $1bn for 100 million doses, which J&J said it expected to supply in the first half of the year. The United States also has the option of purchasing an additional 200 million doses.
The company said it has doses ready for delivery upon emergency approval. It aims to deliver 1bn doses in 2021 with production in the United States, Europe, South Africa and India.
In J&J's trial of nearly 44,000 volunteers conducted in eight countries, the level of protection against Covid-19 was 72pc in the United States, 66pc in Latin America and 57pc in South Africa where variants are circulating.
Those results compare with the 95pc effectiveness of the two-dose vaccines made by Pfizer/BioNTech SE and Moderna.
However, both those trials were conducted mainly in the United States and before the spread of new variants.
J&J's main study goal was the prevention of moderate to severe Covid-19, and the vaccine was 85pc effective in stopping severe disease and preventing hospitalization across all geographies and against multiple variants 28 days after immunization.
J&J's vaccine uses a common cold virus known as adenovirus type 26 to introduce coronavirus proteins into cells in the body and trigger an immune response.
The Pfizer/BioNTech and Moderna vaccines use a new technology called messenger RNA (mRNA) that requires it to be stored in a freezer.