The first results are in from use of an experimental antiviral drug against the new coronavirus.
More than half of a group of 53 patients who received it improved.
But there's no way to know the odds of that happening without the drug because there was no comparison group.
The results published Friday by the New England Journal of Medicine are on remdesivir.
The Gilead Sciences drug has shown promise against other coronaviruses in the past.
The company is testing it in at least five studies around the world and has given it on a case-by-case basis to more than 1,700 patients.