One of the most eagerly anticipated clinical trials of our time has begun. Moderna (MRNA 3.12%) announced Monday that it has started inoculating patients in the phase 3 study of mRNA-1273, its coronavirus vaccine candidate.

The large-scale study will involve around 30,000 participants throughout the U.S., and is being conducted in collaboration with the National Institute of Allergy and Infectious Diseases (NIAID) and the Biomedical Advanced Research and Development Authority (BARDA).

Moderna, a young biotech, was selected to receive extra support from the U.S. government's Operation Warp Speed program, which has the goal of speeding up the development of promising vaccines and treatments for COVID-19. The COVE (coronavirus efficacy) study is placebo-controlled and randomized, and has as its primary endpoint the prevention of symptomatic cases of COVID-19. There are a number of secondary endpoints, most notably the prevention of coronavirus infection entirely.

Researchers working in a laboratory.

Image source: Getty Images.

"We look forward to this trial demonstrating the potential of our vaccine to prevent COVID-19, so that we can defeat this pandemic," said Moderna CEO Stephane Bancel.

While mRNA-1273 is one of nearly 150 coronavirus vaccine candidates being developed across the world, many observers consider it to be among the most promising. Its development has been rapid, and results from its phase 1 study indicate that it produces more than the average number of SARS-CoV-2 antibodies found in individuals who have recovered from COVID-19.

Although there had been reports of some conflict between Moderna and government officials prior to the start of the phase 3 trial, federal agencies have been showering the project with funds. Over the weekend, it was reported that BARDA nearly doubled its grant for the research to up to $955 million.

Moderna stock was trading up by around 9% as of 2:15 p.m. EDT  Monday, well outpacing the 0.5% gain of the broader equities market as measured by the S&P 500 index.