A disease control rate in cancer studies is the percentage of people whose tumors stopped growing.
For mesothelioma, a 100% disease control rate is rare. So when a clinical trial posts a 100% disease control rate, it’s worth taking notice.
A developed and in-testing CAR T-cell therapy for mesothelioma led to impressive results in a phase 1 clinical trial. The study featured 11 people, and all 11 had their tumors stop growing. Six of the 11 (63.6%) had their tumors shrink. One patient even had their tumor disappear thanks to the therapy.
What is CAR T-cell therapy, and why does this particular CAR T-cell therapy work for mesothelioma?
Explaining CAR T-Cell Therapy
CAR T-cell therapy is a type of immunotherapy called cell and gene therapy. CAR T-cell therapy improves patients’ immune system to fight cancer. CAR is an acronym for chimeric antigen receptor.
CAR T-cell therapy engineers a patient’s immune system cells, specifically their T cells, to fight cancer. Scientists engineer the T cells by giving them a new antigen receptor that specifically binds to a receptor on the surface of mesothelioma cells. This connection causes the T cells to look for and attack these cancer cells.
CAR T-cell therapy is approved by the U.S. Food and Drug Administration for certain types of blood cancer: leukemia, lymphoma, and multiple myeloma. It is not yet approved for solid tumors like mesothelioma.
Most solid tumors are too strong for CAR T-cell therapy to combat. The T cells are unable to penetrate into solid tumors, and the immune system often gets tired from attacking for so long.
Mesothelin-Targeting CAR T Cells
Mesothelin is a protein on the surface of mesothelioma cells. The CAR T cells in the successful study were programmed with an antigen receptor looking for mesothelin.
Attacking a protein on the surface of the mesothelioma cells allows the CAR T cells to more easily recognize the disease. Many types of cancer only express proteins within the cells, which are harder to target by the immune system.
The study also armored the CAR T cells with nanobodies. These nanobodies keep the T cells strong and persistent. The nanobody-armored CAR T-cell therapy is called NAC-T.
Mesothelioma is rare and only diagnosed in 3,000 people in the U.S. each year. There are only two systemic treatment options approved by the FDA for this cancer: chemotherapy and immunotherapy.
CAR T-cell therapy is emerging. Strengthening the patient’s T cells and making them more powerful against cancer may lead to another approval soon.
Sources & Author
- Anti-PD-1 Nanobody-Armored MSLN CAR-T Therapy for Malignant Mesothelioma: Preclinical and Clinical Studies. U.S. National Library of Medicine. Retrieved from: https://pubmed.ncbi.nlm.nih.gov/41134065/. Accessed: 10/27/2025.
