With the system, researchers built a CAR gene sequence directly into the DNA of T cells and used it to control tumor growth in several humanized mouse models. According to the undated university statement, the technology must still be scaled for human application; clinical studies are required to examine safety and efficacy.
How the Dual Vector System Works in the Body
One vector, a so-called Enveloped Delivery Vehicle, packages a complete Cas9 gene scissors complex and is according to Eyquem directed specifically to T cells according to the journal GEN through a modified fusion protein and an anti-CD3 antibody fragment. The CAR blueprint is according to Eyquem promoterless and only becomes active when built exactly and in the correct reading frame into the body's own gene site TRAC, which is active only in T cells.
What the Animal Experiments Show
In the first experiment, fourteen days after treatment, CAR integrations were found in around three percent of T cells in the spleen, associated with B cell suppression as functional proof. However, this first effect with the original vector combination was also based on an immune reaction of human donor cells against the mice; without this reaction, a control model according to the authors showed neither detectable CAR-T cells nor B cell suppression. After optimizing both vectors, researchers achieved according to the journal CancerNetwork CAR integration in up to 19.7 percent of T cells in the spleen and controlled tumor growth in several humanized mouse models. According to a report in the journal GEN, in mice with aggressive leukemia, a single injection eliminated every detectable cancer within two weeks in nearly all animals. In models for a form of blood cancer called B-ALL and multiple myeloma, according to CancerNetwork 18 of 20 and all treated mice respectively responded completely; initial responses in a sarcoma model were described as preliminary.
Conventional CAR-T therapies require according to university information the removal of patient immune cells, their genetic modification in a specialized facility, and preparatory chemotherapy, which some patients tolerate poorly. Seven such therapies were approved according to GEN on March 18, 2026, by the U.S. FDA for blood cancer. Eyquem called access according to GEN a global problem because many patients cannot afford the therapy or cannot receive it quickly enough. Eyquem is according to his own information a compensated co-founder of Azalea Therapeutics, which commercially develops the platform and according to GEN from March 18, 2026, planned the first human application by end of 2027.
In Comparison: Other In Vivo CAR-T Approaches
Azalea Therapeutics was according to the journal STAT from March 18, 2026, not the only group that wanted to generate CAR-T cells directly in the body in the future.
Open Questions Until First Patient Study
The available data demonstrate an approach effective in animal experiments that could change CAR-T cell manufacturing; according to the undated university statement, clinical studies are required to examine safety and efficacy.