Add another existing medication to the growing list of treatments that might be useful in the fight against the SARS-CoV-2 coronavirus, and the COVID-19 disease that can result from it. AstraZeneca (NYSE:AZN) announced it will initiate a clinical trial to determine if its Calquence blood cancer drug can help treat COVID-19.

Calquence has Food and Drug Administration (FDA) approval for two types of blood cancer. It works by blocking a protein that regulates the production of a certain type of inflammatory markers. This helps to limit the spread of mutating B cells in instances of blood cancer. It is thought that this could ease the exaggerated immune response seen in the advanced stages of COVID-19.

A medical professional using a microscope.

Image source: Getty Images.

"With this trial we are responding to the novel insights of the scientific community and hope to demonstrate that adding Calquence to best supportive care reduces the need to place patients on ventilators and improves their chances of survival," AstraZeneca wrote in its announcement.

The Calquence trial, christened CALAVI, will take place in the U.S. and in several European countries that weren't named. The U.S. component should open for enrollment within the next few days. It will be a two-part, randomized trial.

According to AstraZeneca, this will be the fastest clinical trial launch in company history.

Other top global pharmaceutical companies are putting approved medications that might combat aspects of COVID-19 into clinical trials at a rapid pace. Gilead is perhaps the best example, while Sanofi and Novartis, among numerous others, are also making such efforts.

AstraZeneca's shares declined by 1.3% on Wednesday, yet that was a slightly better performance than that of the broader stock market.