A coronavirus vaccine candidate similar to that of recently approved ones from Pfizer (PFE 1.59%) and BioNTech (BNTX 0.01%) and Moderna (MRNA 0.53%) has now moved into late-stage testing on healthcare workers.

CureVac (CVAC 3.71%), like BioNTech a clinical-stage biotech based in Europe, announced Monday that its CvnCoV is about to enter phase 3 clinical trials, in testing that involves healthcare workers. The first participant in the study is to be administered the initial shot of the vaccine candidate on Tuesday.

A syringe being filled with a vaccine from a vial.

Image source: Getty Images.

This crucial phase of testing will take place at the University Medical Center Mainz in Germany. It's a randomized, placebo-controlled study with over 2,500 individuals aged 18 and older. CureVac said it compliments the company's phase 2b/3 trial, which involved more than 35,000 people and began last week.

As with Pfizer/BioNTech's and Moderna's vaccines -- both of which are in the initial phases of large-scale rollouts in the U.S. -- CureVac's essentially uses messenger RNA to "instruct" the body's cells how to defend against the coronavirus. CvnCoV was shown to be efficacious in early-stage testing, with no participant developing serious side effects.

CureVac explained the rationale behind this new, specialized testing. "With this clinical study in healthcare workers, we aim to investigate the difference our vaccine candidate can make in this specific group of individuals who are at particularly high risk of potential infection due to viral exposure," the company quoted its head of infectious diseases, Lidia Oostvogels, as saying.

Investors are clearly pleased with the progress CureVac is making with CvnCoV. They traded the stock up by 6.7% on Monday, while the S&P 500 index sank on the day.