Elliott Brea, MD, PhD
Dana-Farber Cancer Institute
Boston
This project proposes to develop novel therapeutic approaches to treat advanced EGFR-mutant NSCLC. CAR-T cell therapy is a type of immunotherapy treatment that uses genetically altered T cells to find and destroy cancer cells more effectively. TROP2 is a protein that is over expressed on the surface of NSCLC and is a target of the antibody-drug conjugate (ADC), sacitizumab-govitecan, which is FDA-approved to treat other solid tumors. Dr. Brea hypothesizes that TROP2-directed CAR-T targeting of EGFR-mutant NSCLC will be superior to standard Osimertinib treatment.
Research Summary
While advances have been made in treating advanced or metastatic cases of Non-small cell lung cancer (NSCLC) with either targeted therapy or immunotherapy, most patients will progress after these first line therapies and require subsequent treatments which are limited in efficacy. EGFR mutant (EGFRm) lung adenocarcinoma is the most common type of NSCLC in patients without a history of tobacco use. They often respond to first line treatments called EGFR inhibitors (EGFRi) that target or block EGFR but unfortunately this is usually not curative in patients with advanced or metastatic EGFR mutant lung cancer. Chimeric antigen receptor T-cell therapy (CAR-T) works by engineering a patient’s immune fighting cells called T-cells to fight the cancer utilizing a receptor, which is matched to proteins expressed on the cell surface of cancer cells. When the receptor recognizes the cancer- associated proteins, T cells bring their powerful anti-cancer attack directly to the malignant cells. CAR-T has shown significant promise in blood cancers with durable responses observed. TROP2 is a protein present in NSCLC and is the target of FDA approved antibody-drug conjugate (ADC) sacitizumab-govitecan for breast and bladder cancer and is in clinical trials for lung cancer. Our goal is to demonstrate that TROP2 directed CAR-T cell therapy is effective in NSCLC, and can eradicate disease in a more durable fashion when compared to standard therapy with EGFRi. We plan to use the results of this work to translate this to clinical trials evaluating this promising strategy for treating lung cancer.
Technical Abstract
While immunotherapies in cancer have allowed for major advances in the field, most patients with advanced or metastatic solid tumors do not achieve durable responses. While CAR-T cell therapy and bispecific antibody therapies which utilize T-cells as their effector have shown promise and durable responses in hematologic malignancies such as DLBCL and multiple myeloma, the promise of similar responses in solid tumors remains an unmet goal. TROP2, a cell surface protein normally expressed during fetal development and at low levels in some normal adult tissue, is over expressed on a variety of solid tumors including NSCLC, and has emerged as an ideal target. TROP2 is the target of the recently FDA approved ADC sacitizumab-govitecan for breast cancer as well as for patients with locally advanced or metastatic urothelial cancer and is currently being tested in phase II/III trials in NSCLC. However, response in patients and in animal models are not durable, even when targeting minimal residual disease (MRD; defined as the residual disease after effective genotype directed systemic treatment). We propose utilizing TROP2 directed CAR-T to target EGFRm NSCLC at MRD, which we hypothesize when compared to TROP2 directed ADC will demonstrate a more durable response. Our preliminary data support the high activity of TROP2 directed CAR-T against EGFRm NSCLC including in the MRD state after osimertinib treatment. We expect these findings to translate to approaches utilizing CAR-T cellular therapy to target the MRD state after targeted therapy.