Another sign of a potential working vaccine from the U.S. company Moderna.
It says its vaccine produced antibodies to the coronavirus in all the patients it tested in an initial safety trial 45 of them in total.
Following the news, Moderna's stock rose on Tuesday by more than 16 percent.
Late stage trials of the vaccine will start on July 27th with 30-thousand participants.
They'll get a dose of 100 micrograms on the first day and another 29 days later.
Some patients will get a placebo.