The Food and Drug Administration approved a twice-yearly shot that prevented HIV infections in 99.9% of the people who received it in large clinical trials. The drug, developed by Gilead Sciences and called Yeztugo,

WASHINGTON — The U.S. has approved the world’s only twice-a-year shot to prevent HIV, the first step in an anticipated global rollout that could protect millions – although it’s unclear how many in the U.S. and abroad will get access to the powerful new option.