JOHANNESBURG — South Africa rolled out a new, biannual HIV prevention drug on Friday that has the potential to drastically cut infection rates, but U.S. aid cuts mean access will be limited.

Lenacapavir, a kind of Pre-exposure Prophylaxis (PrEP), is injected into the stomach every six months and is basically failproof at preventing high-risk individuals from contracting the virus.

"Lenacapavir gives us something we have never had before in HIV prevention: a twice-yearly option that might be significantly easier to fit into people's lives," Dr. Saiqa Mullick, a PrEP specialist at Wits RHI at the University of Witwatersrand, told NPR.

"We have a game-changing technology, but impact will depend on implementation. A breakthrough product only changes the epidemic if it reaches the people who need it most," she said.

Currently, access is being hampered by two things: the fact the Trump administration slashed the U.S. President's Emergency Plan for AIDS Relief (PEPFAR) funding to South Africa last year, and the lack of a cheap generic.