Johnson and Johnson will start coronavirus vaccine trials in humans later this year.
The pharmaceutical company said if all goes well, it hopes the drug will be ready for emergency use by early next year.
Scientists across the world are working to create a vaccine for Covid-19, with some human trials already under way.
Johnson and Johnson said it had started work on a vaccine in January, and is aiming to start testing on people by September.
It anticipates the first batches of a Covid-19 vaccine could be available for emergency use authorisation in early 2021, a substantially accelerated timeframe in comparison with the typical vaccine development process.
The company will also rapidly scale up its manufacturing capacity, with the goal of providing a global supply of more than one billion doses of a vaccine.
Alex Gorsky, chairman and chief executive of Johnson and Johnson, said: “The world is facing an urgent public health crisis and we are committed to doing our part to make a Covid-19 vaccine available and affordable globally as quickly as possible.”