New clinical trial could boost immunotherapy’s power against cancer
Good news: Cancer survival rates are improving. The five-year cancer survival rate has risen from 49 percent in the mid-1970s to 69 percent in 2013, even as the U.S. cancer death rate has decreased by 25 percent through 2014. But these rates could be even better.
A new clinical trial led by Dr. Antoni Ribas of the Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research at UCLA addresses a key shortfall of one of the most promising new ways to treat cancer – adoptive T cell immunotherapy – potentially opening up a way to improve those numbers.
Adoptive T cell immunotherapy typically involves collecting a type of mature white blood cells (the immune system cells) called T cells from patients with cancer. The T cells are genetically modified in the lab to identify and attack a specific type of cancer and then transfused back into the patient. When these genetically modified T cells are returned to the patient, they can more efficiently locate and eliminate cancer cells.
In clinical trials to date, adoptive T cell immunotherapy has shown great promise in treating late-stage tumors that are resistant to traditional cancer treatment methods like surgery, chemotherapy, and radiation. However, this method has limitations: Once transplanted back into patients, the population of modified T cells declines over time, which can lead to cancer recurrence.
Ribas’ clinical trial aims to overcome this limitation through a dual approach that creates both a short-term and long-term immune response. The method involves collecting both mature T cells and blood-forming stem cells from patients, genetically modifying them to target a common cancer tumor marker, and then returning the modified cells to the patients.
By adding blood-forming stem cells to the mature T cells that are traditionally deployed in adoptive T cell immunotherapies, this treatment addresses the issue of T cell population decline. Blood-forming stem cells give rise to all types of blood cells, including T cells, throughout a person’s life. Therefore, the engineered blood stem cells are able to boost the immune system with a continual supply of cancer-fighting T cells after the initial group of T cells has declined.
The result is a two-pronged attack on cancer: The modified mature T cells begin targeting cancer cells immediately while the blood-forming stem cells begin generating an ongoing supply of modified T cells that will carry on the fight, potentially preventing cancer recurrence.
The trial, which is funded by the California Institute for Regenerative Medicine, is currently open to people with tumors that have metastasized, meaning the cancer has spread to other parts of the body from its initial location. Potential participants must also have a specific tumor marker, called NY-ESO-1, and a specific type of immune system, called HLA-A2.1.
While the scope of this trial is highly specific, Ribas is optimistic that it will pave the way for future treatments for other cancers. “My hope is that the therapeutic principles and procedures developed in this trial will be applicable to a wider range of cancers in the future,” he said.
To learn more about this clinical trial, visit its page at clinicaltrials.gov. If you think you might be eligible to enroll, please contact Clinical Research Coordinator Justin Tran by email at firstname.lastname@example.org or by phone at 310-206-2090.