The companies are partnering with the U.S. Department of Health and Human Services (HHS) Operation Warp Speed project and the Department of Defense to fund development and scale up manufacturing capabilities.

The U.S. government will provide up to $2.1 billion for manufacturing scale-up and delivery of an initial 100 million doses of the vaccine. Sanofi will receive a majority of the funding. The government has a further option for the supply of an additional 500 million doses longer term.

The vaccine candidate being jointly developed by the companies is based on recombinant-protein technology used by Sanofi to produce an influenza vaccine, and GSK's pandemic adjuvant technology.

The companies anticipate beginning a phase I/II study in September, led by Sanofi, and a phase III study by the end of 2020. Upon successful clinical development, the companies hope to request regulatory approval in the first half of 2021. Simultaneously, the companies will scale up manufacturing of the antigen and adjuvant to produce up to one billion doses per year globally.

There are active discussions with the European Commission for the supply of the vaccine in Europe. The companies expect to provide a portion of the total worldwide available supply to the global initiative "Access to COVID‐19 Tools (ACT) Accelerator."