After months of waiting, the world finally has its first coronavirus drug to be fully approved by a major regulator. On Thursday, the U.S. Food and Drug Administration (FDA) granted approval to Gilead Sciences' (GILD -0.21%) remdesivir -- sold under the brand name Veklury -- to treat the illness in patients 12 years of age and older in cases requiring hospitalization.

Remdesivir had been in use previously under an Emergency Use Authorization (EUA), which was granted in May from the same regulator. It holds the same status in around 50 other countries around the world.

Gloved hands holding a vial of medicine.

Image source: Getty Images.

The usual course of treatment with remdesivir is five days, during which time, six vials of the drug are administered. At the moment, it can only be taken intravenously. Gilead is currently developing an inhaled version.

Remdesivir was originally designed and developed to treat Ebola, although it didn't prove to be more effective than other medications. It was repurposed to target COVID-19.

The FDA's approval was based on data from three clinical studies of the drug. The regulator quoted its Commissioner Stephen Hahn as saying that, "Today's approval is supported by data from multiple clinical trials that the agency has rigorously assessed and represents an important scientific milestone in the COVID-19 pandemic."

Upon winning approval, Gilead pledged to do further work in developing the drug. "We will continue to work at speed with the aim of enhancing patient outcomes with Veklury to ensure all patients with COVID-19 have the best chance at recovery," the company quoted its CEO Daniel O'Day as saying.