A groundbreaking annual injection designed to protect against Human Immunodeficiency Virus (HIV) has successfully passed an important early safety trial.
Researchers have shared that the drug lenacapavir prevents the virus from replicating inside cells. If further testing proves successful, this could become the longest-lasting form of HIV prevention available.
Currently, individuals at risk of HIV can take daily pills or receive injections every eight weeks as part of pre-exposure prophylaxis (PrEP).
Although highly effective, the need for regular doses can be challenging.
The prospect of a once-a-year injection could significantly improve accessibility and adherence to HIV prevention methods.
A yearly HIV dose
In the initial trial, 40 participants who did not have HIV received a single muscle injection of lenacapavir.
The results showed no major side effects or safety concerns.
Remarkably, traces of the medication remained in their bodies after 56 weeks, suggesting its potential as an annual PrEP option.
Future trials will need to involve a more diverse group of participants, researchers emphasized at the 2025 Conference on Retroviruses and Opportunistic Infections.
However, they remain optimistic about the drug’s potential.
As they noted, “Yearly dosing of lenacapavir has the potential to further decrease current barriers to PrEP by increasing the uptake of, persistence on, and, therefore, scalability of PrEP.”
This development could play a key role in global efforts to curb the HIV epidemic. According to the World Health Organization (WHO), around 39.9 million people are currently living with HIV, with 65% of cases in the African region.
Organizations like WHO, the Global Fund and UNAIDS are working to improve access to HIV-prevention medicines in hopes of ending the epidemic by 2030.
Lenacapavir brings hope
Lenacapavir’s success in early trials has sparked excitement among HIV advocacy groups. Richard Angell, from the Terrence Higgins Trust, called the results “as exciting as they are transformational.”
“PrEP as a daily pill has been a game-changer in our HIV response,” he said.
“The prospect of ‘safe’ annual injectable PrEP is as exciting as it is transformational. It’s great to see these early results that suggest injectable PrEP might be effective for up to 12 months. We need to get ready for its rollout now and fund sexual-health clinics to do so.”
This statement reflects a growing demand for more convenient HIV prevention options that could reach more people and simplify treatment plans.
Inequalities in PrEP access
Despite the effectiveness of PrEP, access to these medications has been uneven. Angell highlighted existing disparities, stating, “The oral pill is still not available in prisons, online or in community pharmacy.”
He also pointed out regional differences in PrEP availability, noting that while Scotland has approved two-monthly PrEP injections, England still awaits the National Institute for Health and Care Excellence (NICE) approval.
With ongoing advancements in HIV prevention, experts hope that new long-acting treatments like lenacapavir can bridge these gaps and make protection more widely available.
If further trials confirm its effectiveness, this annual injection could revolutionize the fight against HIV, making prevention easier and more accessible for millions worldwide.
The research was published in The Lancet medical journal.