Another pill to treat COVID-19 is on the way.

The Food and Drug Administration on Thursday granted emergency use authorization to a pill to treat COVID-19 from Merck for adults who are at high risk of severe disease and “for whom alternative COVID-19 treatment options authorized by the FDA are not accessible or clinically appropriate.” Molnupiravir is intended to be taken within five days of the onset of symptoms. 

The pill isn’t authorized for patients younger than 18 because it “may affect bone and cartilage growth,” and it isn’t authorized “for initiation of treatment in patients hospitalized due to COVID-19 because benefit of treatment has not been observed in people when treatment started after hospitalization due to COVID-19,” the FDA said. Merck previously said the pill cut the risk of hospitalization and death by 30 percent. 

“Today’s authorization provides an additional treatment option against the COVID-19 virus in the form of a pill that can be taken orally,” FDA Center for Drug Evaluation and Research director Dr. Patrizia Cavazzoni said. “Molnupiravir is limited to situations where other FDA-authorized treatments for COVID-19 are inaccessible or are not clinically appropriate and will be a useful treatment option for some patients with COVID-19 at high risk of hospitalization or death.” 

This came a day after the FDA granted emergency use authorization to a COVID-19 pill from Pfizer, although the White House noted it will take months for it to become widely available. As with the Pfizer pill, the FDA stressed that neither of these treatments are substitutes for COVID-19 vaccines.