UCHealth is preparing to launch a phase three study for another COVID-19 vaccine, the third coronavirus inoculation trial undertaken by the Colorado hospital giant since the pandemic began.

This latest "investigational vaccine," as UCHealth called it in a Monday news release, is made by Novavax. The trial is supported by the National Institutes of Health.

UCHealth will begin recruiting participants for the final phase of the vaccine's trials, a process that will "run about two months," the system said.

 “This pivotal phase 3 clinical trial in the U.S. and Mexico is critical to building on the encouraging safety and immunogenicity data we’ve generated to-date and ultimately demonstrating how well (the Novavax vaccine) works to prevent COVID-19,” Gregory M. Glenn, Novavax's president for research and development, said in a statement.

“We are grateful to the thousands of volunteers who are stepping forward to participate in this vital research.”

UCHealth is still participating in a trial for the AstraZeneca dose, another vaccine candidate that officials have said will likely receive approval in the coming weeks.

Another trial, for the already cleared Moderna vaccine, concluded at the end of October.

Phase three trials are typically the largest and final initial study of vaccines and other medications. It will include thousands of patients in Colorado and Mexico, the hospital system said in its announcement.

Two-thirds of the UCHealth participants in this latest trial will receive a dose of the vaccine candidate, while a third will be given a placebo.

"The emphasis of the Novavax phase 3 trial is on demonstrating safety and effectiveness of the vaccine in people who are most at-risk for contracting and becoming ill from COVID-19," the system wrote.

"UCHealth will also recruit individuals in higher-risk groups including Black, Hispanic, American Indian and Alaska Native study participants as well as those with certain health conditions, including those over 65 years old and people suffering from diabetes, obesity, heart disease, lung disease, or chronic kidney disease."

The results from the phase one and two trials, which began in May, were published in the New England Journal of Medicine last month. The authors of the report wrote that no participants had no "severe adverse events."

The initial phase of the vaccine's trial included two injections per patient; the Moderna and Pfizer vaccines also require two doses.

Those two vaccines received approval in December and are being distributed across Colorado and nationwide.

Officials have said they expect another two vaccines -- one made by AstraZeneca and another from Johnson & Johnson -- to be approved soon to further bolster the nation's vaccine rollout.