The US government’s current supply of remdesivir, the only drug known to work against Covid-19, will run out at the end of the month, a federal health official told CNN.

The government’s last shipment of the drug will go out the week of June 29. Gilead Sciences, the company that makes the drug, is ramping up to make more, but it’s unclear how much will be available this summer.

“Right now, we’re waiting to hear from Gilead what is their expected delivery availability of the drug as we go from June to July,” said Dr. Robert Kadlec, a US Department of Health and Human Services official.
“We’re kind of not in negotiations, but in discussions with Gilead as they project what the availability of their product will be.”

Last month, the US Food and Drug Administration gave emergency authorization for remdesivir, an intravenous antiviral medication studied to treat Ebola but now used on hospitalized Covid patients.

While not a blockbuster drug, a study shows it shaves four days off a hospital stay, from 15 to 11 days.