Injectable lenacapavir (LEN) for PrEP is a new antiretroviral (ARV) drug that is highly effective at preventing HIV. Below are details on its distinct characteristics, ongoing Phase II and III clinical trials, approval status by country, as well as resources to learn more.
The Basics
- Given every six months.
- Two subcutaneous injections given on the same visit in the abdomen.
- The first visit also involves taking two pills with the first set of injections followed by two more pills the following day.
- Developed by Gilead.
- Approved in multiple countries as treatment under the brand name Sunlenca.
- Shown to be highly effective at preventing HIV in two large Phase III clinical trials, PURPOSE 1 and PURPOSE 2. Early results from PURPOSE 1 showed no HIV infections in the LEN for PrEP arm, and early results from PURPOSE 2 showed only two infections in the LEN for PrEP arm.
- Approved in June 2025 by the US Food and Drug Administration as pre-exposure prophylaxis (PrEP).
- Gilead has also submitted LEN for PrEP to the European Medicines Agency, which covers all countries in the European Economic Area, to the South African Health Products Regulatory Authority, and to Brazil’s ANVISA.
- Three smaller Phase II clinical trials- PURPOSE 3, PURPOSE 4, and PURPOSE 5- are investigating safety and efficacy in populations not included in PURPOSE 1 and 2.
- A one-year version of LEN for PrEP is also under investigation. Early results have been positive, and a Phase III clinical trial is expected to launch later in 2025.
The Trials
PURPOSE 1
- Conducted among approximately 5,000 cisgender women in South Africa and Uganda.
- Testing the efficacy of both LEN for PrEP and the daily pill emtricitabine/tenofovir alafenamide (F/TAF) in preventing HIV.
- In June 2024, the trial was unblinded after meeting its primary endpoint of superiority to oral PrEP (TDF/FTC) and background HIV incidence.
- Scheduled to run until July 2027.
- The first Phase III clinical trial to include pregnant and lactating people from the start—which could make it easier to get approval for use in this population if found to be effective and safe.
- Read a summary here and the full results from the New England Journal of Medicine here.
PURPOSE 2
- Conducted among 3,000 men who have sex with men, gay men, transgender men, transgender women, and gender non-binary people in Argentina, Brazil, Mexico, Peru, Puerto Rico, South Africa, Thailand, and the USA.
- In September 2024, the trial was unblinded after meeting its primary endpoint of superiority to oral PrEP (TDF/FTC) and background HIV incidence.
- Scheduled to run until April 2027.
- Read a summary here and the full results from the New England Journal of Medicine here.
PURPOSE 3
- Conducted among 250 cisgender women in the USA.
- Scheduled to run until January 2028.
PURPOSE 4
- Conducted among 250 people who inject drugs in the USA.
- Scheduled to run until July 2027.
PURPOSE 5
- Conducted among 262 men who have sex with men, gay men, transgender men, transgender women, and gender non-binary people in France and the United Kingdom.
- Scheduled to run until July 2029.
Where can I access LEN for PrEP?
LEN for PrEP is not yet available outside of clinical trials, though several countries are currently preparing for introduction. To see where LEN for PrEP is currently approved and where approval is pending, see the graphic below or visit our Country Planning for Product Introduction Matrix.
Click to enlarge
Further Resources
Reports and Guides
- The Gears of Lenacapavir for PrEP Rollout — this report provides a framework for accelerated and equitable introduction of injectable lenacapavir (LEN) for PrEP, including outlining priority actions for different stakeholder groups.
- From Clinical Trial Efficacy to Public Health Impact: A plan for accelerating access to injectable lenacapavir for PrEP — this plan provides a comprehensive view of all the moving parts for lenacapavir for PrEP introduction and identifies priority actions and actors responsible for ensuring time is not wasted and opportunity not squandered.
- The Lens on LEN — AVAC’s primer on lenacapavir
- Getting PrEP Rollout Right this Time: Lessons from the Field — this report examines key insights from the rollout of oral PrEP and early introduction of CAB and DVR to inform a faster, smarter and more equitable introduction of future HIV prevention tools, such as lenacapavir
Infographics
- Tracking Lenacapavir Rollout — interactive graphics outlining immediate next steps on pathways to access and impact, key actors responsible for them, timelines for completion, and important progress updates
- An Overview of LEN for PrEP Trials
- Lenacapavir for PrEP Regulatory Approvals Map
- Where we are with LEN for PrEP
- Moving a Product to the Real World
- LEN Generics: Can we go faster?
Understanding Trial Results
- An Overview of LEN for PrEP Trials
- AVAC’s press release on the PURPOSE 1 trial interim results
- Gilead’s press release on the PURPOSE 1 trial interim results
- AVAC’s press release on the PURPOSE 2 trial interim results
- Gilead’s press release on the PURPOSE 2 trial interim results
- Summary of PURPOSE 1 trial and results
Webinars
- The Scientific Journey of Lenacapavir: From basic science to clinical development to impact — his webinar explored how US support from NIH for basic science and South Africa’s clinical research infrastructure made possible the development of lenacapavir
Access
The graphic below compares lenacapavir with another injectable PrEP product, cabotegravir. Click here to download the graphic.
