Researchers at Oregon Health & Science University and the Oregon National Primate Research Center reported long-term SHIV suppression using an AAV gene therapy delivering a CCR5-blocking antibody (leronlimab). The work, published in Science Translational Medicine, was conducted in 19 SHIV-infected macaques. Most animals showed detectable antibody levels following AAV administration, with an immune response developing in about half. Over a year of follow-up, animals with pre-existing anti-leronlimab antibodies failed to sustain detectable expression, while others maintained partial or full suppression depending on immune dynamics. The study matters for gene-therapy feasibility in chronic infectious disease by showing that sustained biologic activity can persist amid immune pressure, while highlighting the impact of pre-existing antibodies on durability.