What is Lenacapavir?

On June 19, 2025, the U.S. Food and Drug Administration (FDA) approved a groundbreaking drug called Lenacapavir—the first long-acting injectable medication in the world that can prevent HIV with just two shots per year. This marks a major breakthrough in the decades-long battle against the global HIV/AIDS epidemic and offers a powerful new tool to protect millions at risk.

Unlike traditional vaccines, Lenacapavir is not an immunization. Instead, it’s an antiretroviral drug that works by maintaining high levels of medication in the body, effectively blocking the replication of HIV if exposure occurs. In clinical trials conducted by Gilead Sciences, the manufacturer, Lenacapavir showed remarkable effectiveness—96% protection in heterosexual women, and 100% in gay, bisexual, and gender-diverse individuals. These results far surpass the efficacy of existing oral PrEP (pre-exposure prophylaxis) pills, which require daily intake and often face issues with user adherence.

Lenacapavir was initially approved in 2022 for treating patients with drug-resistant HIV. However, during expanded clinical trials, researchers discovered two unique characteristics:

These properties laid the foundation for shifting its use from treatment to prevention, revolutionizing how we think about HIV protection.

"This could truly end HIV transmission," said Greg Millett, director of public policy at amfAR, the Foundation for AIDS Research.

Dr. David Ho, a leading HIV researcher at Columbia University, also hailed Lenacapavir as a "major scientific breakthrough", especially at a time when global HIV prevention efforts are facing reduced funding.

However, despite its scientific promise, Lenacapavir faces significant real-world barriers:

For over 40 years, researchers have tried to develop an effective HIV vaccine, but none have delivered promising results. Now, Lenacapavir’s high prevention success rate is so compelling that it’s becoming difficult to conduct vaccine trials, since researchers cannot ethically ask participants to forego a proven method of protection.

According to Hui Yang, Director at the Global Fund to Fight AIDS, Tuberculosis and Malaria: “Long-acting drugs like Lenacapavir could improve adherence and expand reach. This is a chance to accelerate HIV prevention in the coming decade.”

In summary, Lenacapavir represents a new era in HIV prevention - offering powerful, long-lasting protection with just two injections per year. While affordability and accessibility remain key challenges, its approval is a bold step forward in the global effort to end HIV transmission once and for all.