Scientists at the University of California, San Francisco have presented compelling evidence that a single infusion of engineered immune cells could suppress H.I.V. for years. The study, revealed at a gene therapy conference in Boston, showed two patients achieving undetectable viral levels—one for nearly nearly two years. This approach adapts CAR-T cell therapy, previously successful against certain blood cancers.

Researchers at Caring Cross, a nonprofit, modified patients' T-cells to carry dual molecules: one that binds to and destroys H.I.V.-infected cells, another that prevents the immune cells themselves from becoming infected. Participants stopped antiretroviral drugs on infusion day. Three early-treated patients showed some degree of control, while three with long-standing H.I.V. did not respond, suggesting timing matters significantly.

The findings represent proof-of-concept for a potential functional cure, though widespread availability remains decades away. More than 40 million people globally live with H.I.V., with most relying on daily medication. Scientists now aim to refine the therapy and scale production, with researchers suggesting costs could eventually drop below $10,000 per treatment.