Twice-yearly injections of the capsid inhibitor drug lenacapavir can prevent the vast majority of HIV infections, according to a Phase 3 clinical trial published Wednesday in the New England Journal of Medicine.
HIV pre-exposure prophylaxis (PrEP) has emerged as a crucial tool for fighting the global HIV epidemic, but researchers say daily pill regimens remain an obstacle to treatment adherence. “Long acting antiretrovirals have raised the bar with respect to the reach, efficacy and effectiveness that can be achieved in our efforts to prevent HIV,” said Onyema Ogbuagu, MBBCh, associate professor of medicine and pharmacology at Yale School of Medicine and director of the Yale Antivirals and Vaccines Research Program, who was the senior author of the study.
The trial enrolled 3,271 cisgender men and gender-diverse people and compared HIV twice-yearly lenacapavir injection to background infection rates and to Truvada, a daily pill for PrEP. Researchers say among 2,179 participants in the lenacapavir group, they found only two incident HIV infections – a 96% reduction compared to background HIV incidence. The Truvada group had nine incident cases among 1,086 participants. No new or significant safety concerns were identified.
The trial found lenacapavir decreased HIV incidence by 89% compared to Truvada. “Our study showed that twice-yearly injectable lenacapavir, beyond protecting 99.9% of recipients from acquiring HIV, superiorly outperformed a standard of care oral comparator, was safe and well tolerated,” Ogbuagu said.
Researchers say the nine participants in the Truvada group who experienced incident HIV infection showed evidence of low or no treatment adherence, underscoring the importance of PrEP options that fit a variety of patients and lifestyles. “With these results, we now have a new, potent and proven tool that can allow us expand and strengthen efforts to end HIV transmission globally,” Ogbuagu added.
About Yale School of Medicine
Yale School of Medicine educates leaders in medicine and science, fostering curiosity and critical inquiry in a diverse, inclusive environment. It is a global leader in biomedical research, clinical care, and medical education, ranking fourth in NIH funding and tenth in NIH dollars per faculty member. With over 1,700 physicians, Yale provides compassionate care to patients worldwide. The Yale System of Medical Education emphasizes critical thinking and independent research, producing leaders in academic medicine.
News
World’s Rivers “Overdosing” on Human Antibiotics, Study Finds
Researchers estimate that approximately 8,500 tons of antibiotics enter river systems each year after passing through the human body and wastewater treatment processes. Rivers spanning millions of kilometers across the globe are contaminated with [...]
Yale Scientists Solve a Century-Old Brain Wave Mystery
Yale scientists traced gamma brain waves to thalamus-cortex interactions. The discovery could reveal how brain rhythms shape perception and disease. For more than a century, scientists have observed rhythmic waves of synchronized neuronal activity [...]
Can introducing peanuts early prevent allergies? Real-world data confirms it helps
New evidence from a large U.S. primary care network shows that early peanut introduction, endorsed in 2015 and 2017 guidelines, was followed by a marked decline in clinician-diagnosed peanut and overall food allergies among [...]
Nanoparticle blueprints reveal path to smarter medicines
Lipid nanoparticles (LNPs) are the delivery vehicles of modern medicine, carrying cancer drugs, gene therapies and vaccines into cells. Until recently, many scientists assumed that all LNPs followed more or less the same blueprint, [...]
How nanomedicine and AI are teaming up to tackle neurodegenerative diseases
When I first realized the scale of the challenge posed by neurodegenerative diseases, such as Alzheimer's, Parkinson's disease and amyotrophic lateral sclerosis (ALS), I felt simultaneously humbled and motivated. These disorders are not caused [...]
Self-Organizing Light Could Transform Computing and Communications
USC engineers have demonstrated a new kind of optical device that lets light organize its own route using the principles of thermodynamics. Instead of relying on switches or digital control, the light finds its own [...]
Groundbreaking New Way of Measuring Blood Pressure Could Save Thousands of Lives
A new method that improves the accuracy of interpreting blood pressure measurements taken at the ankle could be vital for individuals who are unable to have their blood pressure measured on the arm. A newly developed [...]
Scientist tackles key roadblock for AI in drug discovery
The drug development pipeline is a costly and lengthy process. Identifying high-quality "hit" compounds—those with high potency, selectivity, and favorable metabolic properties—at the earliest stages is important for reducing cost and accelerating the path [...]
Nanoplastics with environmental coatings can sneak past the skin’s defenses
Plastic is ubiquitous in the modern world, and it's notorious for taking a long time to completely break down in the environment - if it ever does. But even without breaking down completely, plastic [...]
Chernobyl scientists discover black fungus feeding on deadly radiation
It looks pretty sinister, but it might actually be incredibly helpful When reactor number four in Chernobyl exploded, it triggered the worst nuclear disaster in history, one which the surrounding area still has not [...]
Long COVID Is Taking A Silent Toll On Mental Health, Here’s What Experts Say
Months after recovering from COVID-19, many people continue to feel unwell. They speak of exhaustion that doesn’t fade, difficulty breathing, or an unsettling mental haze. What’s becoming increasingly clear is that recovery from the [...]
Study Delivers Cancer Drugs Directly to the Tumor Nucleus
A new peptide-based nanotube treatment sneaks chemo into drug-resistant cancer cells, providing a unique workaround to one of oncology’s toughest hurdles. CiQUS researchers have developed a novel molecular strategy that allows a chemotherapy drug to [...]
Scientists Begin $14.2 Million Project To Decode the Body’s “Hidden Sixth Sense”
An NIH-supported initiative seeks to unravel how the nervous system tracks and regulates the body’s internal organs. How does your brain recognize when it’s time to take a breath, when your blood pressure has [...]
Scientists Discover a New Form of Ice That Shouldn’t Exist
Researchers at the European XFEL and DESY are investigating unusual forms of ice that can exist at room temperature when subjected to extreme pressure. Ice comes in many forms, even when made of nothing but water [...]
Nobel-winning, tiny ‘sponge crystals’ with an astonishing amount of inner space
The 2025 Nobel Prize in chemistry was awarded to Richard Robson, Susumu Kitagawa and Omar Yaghi on Oct. 8, 2025, for the development of metal-organic frameworks, or MOFs, which are tunable crystal structures with extremely [...]
Harnessing Green-Synthesized Nanoparticles for Water Purification
A new review reveals how plant- and microbe-derived nanoparticles can power next-gen water disinfection, delivering cleaner, safer water without the environmental cost of traditional treatments. A recent review published in Nanomaterials highlights the potential of green-synthesized nanomaterials (GSNMs) in [...]















