Biotechnology company Moderna Inc. said Monday that its experimental vaccine was 94.5 percent effective in preventing COVID-19, making it the second U.S. firm to show promising results in developing a vaccine against the coronavirus pandemic.

The Massachusetts-based company said it plans to apply for emergency use authorization in the United States in the coming weeks and also submit authorization applications to global regulatory agencies.

A view of U.S. biotechnology company Moderna Inc.'s headquarters in Cambridge, Massachusetts, on May 8, 2020. (Getty/Kyodo) 

The company has an agreement with the Japanese government to supply the Asian country with enough vaccine doses for 25 million people starting in the first half of next year. Once the vaccine is approved, Japan's Takeda Pharmaceutical Co. will sell and distribute the doses.

"This is a pivotal moment in the development of our COVID-19 vaccine candidate," Moderna CEO Stephane Bancel said upon announcing the company's interim analysis from the final-stage clinical trial of the mRNA-type vaccine.

The trial involving the two-dose vaccine enrolled more than 30,000 participants in the United States. The analysis was based on 95 participants with confirmed cases of COVID-19, five of whom had been vaccinated while 90 received dummy shots, resulting in an estimated vaccine efficacy of 94.5 percent, according to Moderna.

All 11 severe cases of COVID-19 were in people who had received the placebo.

Side effects included fatigue and muscle aches, but they were generally short-lived, the company said.

By the end of 2020, Moderna expects to have approximately 20 million doses of the vaccine ready to ship in the United States. It is also on track to manufacture 500 million to one billion doses globally in 2021.

Just a week earlier, U.S. pharmaceutical giant Pfizer Inc. said it had found its potential mRNA vaccine was more than 90 percent effective during a late-stage clinical study.

Vaccines using mRNA, which is made from DNA, can provide instructions for cells in the body to make proteins that will lead the immune system to start to produce a defensive response against a virus.

The successful findings are raising hopes toward a breakthrough in the nearly year-long global fight against the novel coronavirus pandemic.

More than 54 million cases of COVID-19 have been confirmed around the world, with the death toll topping one million, according to a tally by Johns Hopkins University. The United States remains the country with the highest number of confirmed cases and deaths.