Moderna and Pfizer both launched late-stage clinical trials of their experimental COVID-19 vaccines July 27.
Moderna's phase 3 trial includes 89 sites and about 30,000 people. The results of the trial, expected by November, will determine whether two doses of its vaccine can protect against symptomatic COVID-19 and whether it should be approved for widespread use.
The drugmaker also said July 26 it has received an additional $472 million from the Biomedical Advanced Research Development Authority, a division of HHS, to support late-stage clinical development of its vaccine, on top of the $483 million it previously received.
Moderna said it decided to conduct a significantly larger phase 3 clinical trial than initially expected, which is why it required more funding. It remains on track to deliver about 500 million doses per year beginning in 2021, with the potential to manufacture up to 1 billion doses every year, Moderna said.
Pfizer's phase 2/3 trial includes about 120 sites and up to 30,000 people and will evaluate if a vaccine it developed in a partnership with BioNTech is effective at preventing COVID-19 infection. The one it is testing is different from the one it announced results for earlier this month, according to The Wall Street Journal.
Pfizer said it expects trial results as early as October and if successful, plans to supply up to 100 million doses by the end of 2020 and 1.3 billion by the end of 2021.