In a trial, Gilead's twice-yearly shot reduced HIV infections by 96%.

• A second large study showed that Gilead's twice-yearly shot reduced HIV infections by 96%, the company announced on Thursday.
• The data supports the likelihood of FDA approval for Lenacapavir as an HIV prevention medication.
• Shares rose 3% in premarket trading.

The company announced that a second large study showed a 96% reduction in HIV infections after receiving the shot twice a year.

The positive results from the phase three trial of Lenacapavir increase the likelihood of the U.S. Food and Drug Administration approving it for HIV prevention.

Gilead CEO Daniel O'Day stated that with a comprehensive dataset from multiple study populations, the company will work urgently with regulatory, government, public health, and community partners to ensure that, if approved, twice-yearly lenacapavir for PrEP can be delivered worldwide to all those who want or need it.

According to the Centers for Disease Control and Prevention, PrEP is a medication that prevents HIV infection by being taken before exposure to the virus.

Gilead shares climbed about 3% in premarket trading Thursday.

The trial of Lenacapavir showed that 99.9% of participants did not acquire HIV, with two cases among 2,180 people. The study included cisgender men, transgender men, transgender women, and gender non-binary individuals who have sex with partners assigned male at birth.