Federal drug regulators this week affirmed landmark study results showing that a popular HIV-fighting pill can also help healthy people avoid contracting the virus that causes AIDS in the first place.

While the pill appears safe and effective for prevention, scientists stressed that it only works when taken every day.

The Food and Drug Administration held a meeting Thursday to discuss whether Truvada should be approved for people who are at risks of contracting HIV through sexual intercourse. The agency’s positive review posted Tuesday suggests the daily pill will become the first drug approved to prevent HIV infection in high-risk patients.