A remarkable new study, published on February 28, 2025, in Science, in its Science Immunology section,, has demonstrated what could be a game-changing approach to treating HIV — using a single injection to deliver antibodies that can control the virus for more than a year without daily medication.
The Current Challenge
For people living with HIV today, treatment typically means taking antiretroviral therapy (ART) pills every day for life. While these medications have dramatically improved life expectancy, they come with significant drawbacks: potential side effects, daily adherence requirements, cost issues, and access challenges in many parts of the world.
The Breakthrough Approach
Researchers led by Dr. David Evans and colleagues have demonstrated a promising alternative using a viral delivery system called AAV (adeno-associated virus) to provide long-lasting protection against SIV (simian immunodeficiency virus) — the monkey equivalent of HIV.
In their study published in Science Immunology, the team showed that a single injection could deliver genes that instruct the body to continuously produce special antibodies against the virus.
How It Works
The approach uses a harmless virus (AAV) as a delivery truck. This virus is engineered to carry instructions for making two antibodies that target the envelope protein of SIV. Once delivered to muscle cells, these cells become factories that continuously produce the antibodies.
The two antibodies work in complementary ways:
- One antibody directly neutralizes the virus, preventing it from infecting new cells.
- Both antibodies can tag infected cells for destruction by the immune system (a process called antibody-dependent cellular cytotoxicity or ADCC).
The Remarkable Results
The researchers tested this approach in monkeys infected with SIV who were initially treated with standard antiretroviral drugs. When the daily drugs were stopped:
- In all control animals, the virus quickly rebounded within 2 weeks.
- In half of the treated animals, viral levels remained undetectable for more than a year after stopping medication.
What makes this particularly impressive is that SIV is considered even more difficult to control than HIV, and the viral reservoir in monkeys is thought to be about 10 times larger than in humans with HIV.
What Sets This Approach Apart?
Previous attempts at this strategy faced a significant obstacle: the body would often generate “anti-drug antibodies” that neutralized the therapeutic antibodies, rendering the treatment ineffective.
The key innovation in this study was using natural monkey antibodies rather than modified human antibodies. This dramatically reduced the immune rejection response, allowing the antibodies to persist at therapeutic levels.
Implications for HIV Treatment
While this research is still in the experimental stage, it suggests a pathway toward what many consider the holy grail of HIV treatment — a “functional cure” where the virus remains present but is controlled without daily medication.
For Dr. Evans and team, the next steps will likely include testing combinations of multiple antibodies to prevent viral escape (where the virus mutates to avoid recognition) and ultimately moving toward human trials.
If successful in humans, this approach could transform HIV treatment from a daily pill regimen to perhaps a yearly injection — making treatment more accessible, convenient, and potentially more effective for millions of people worldwide.
Research Study Source
Klenchin, V. A., Clark, N. M., Keles, N. K., Capuano III, S., Mason, R., Gao, G., Broman, A., Kose, E., Immonen, T. T., & Evans, D. T. (2025). Adeno-associated viral delivery of Env-specific antibodies prevents SIV rebound after discontinuing antiretroviral therapy. Science, Science Immunology section. Retrieved from https://www.science.org/doi/10.1126/sciimmunol.adq4973.
Disclaimer
This article is a journalistic review and summary of a research study published in Science Immunology. The research findings described were conducted by Dr. David Evans and colleagues and are reported here for informational purposes only. Our magazine has not independently verified the study’s methodologies or results. Scientific research, particularly in experimental stages, should be interpreted with appropriate caution. The study reviewed here was conducted in animal models and has not yet been tested in humans. While we strive to explain complex scientific concepts accurately, readers should refer to the original publication for complete details. This article does not constitute medical advice, and people living with HIV should continue to follow treatment plans prescribed by their healthcare providers. The timeline for potential human applications remains uncertain, and significant additional research would be required before any therapy described could potentially become available to patients.
