Scientists at UC San Francisco announced on March 19 a new method to reprogram cancer-fighting immune cells directly inside the body, potentially removing barriers of time and cost associated with current CAR-T cell therapies. This development could make advanced cancer treatments more accessible to patients who previously could not afford or tolerate them.
The innovation is significant because traditional CAR-T therapy requires extracting a patient’s immune cells, modifying them in specialized facilities, and then reinfusing them—a process that can take weeks and cost hundreds of thousands of dollars. The new approach allows for precise genetic modification of T cells within the patient, which may lead to faster and less expensive treatments.
According to the research published in Nature on March 18, scientists used a two-particle system in mice with humanized immune systems. One particle delivered CRISPR-Cas9 gene-editing tools to T cells circulating in the body, while the other carried new DNA instructions for targeting cancer. This method successfully treated aggressive leukemia, multiple myeloma, and even a solid tumor—an area where previous CAR-T therapies have struggled.
Justin Eyquem, Ph.D., associate professor at UCSF and senior author of the study, said: “I think this is just the beginning of a big wave of new therapies that will be truly transformational and save a lot of lives.” He added: “It’s become a global access issue. There has been a big push in the field to try to move to directly producing these cells in the body.”
In experiments led by William Nyberg, Ph.D., and Pierre-Louis Bernard, Ph.D., nearly all mice cleared detectable cancer within two weeks after receiving a single injection. The engineered T cells also appeared more effective than those produced outside the body. Eyquem said: “What was especially remarkable was that the cells we’re generating in vivo actually look better than what we make in the lab.”
Clinical trials are needed before this method can be used in humans. Eyquem and collaborators have founded Azalea Therapeutics to advance clinical development. “If we can translate this to humans, we could dramatically reduce costs, eliminate waiting times, and potentially allow community hospitals — not just major cancer centers — to offer these life-saving therapies,” he said.
