Dr Fakih on the BASECAMP-1 Study in HLA-A*0201-Positive Solid Tumors

Marwan G. Fakih, MD, Judy & Bernard Briskin distinguished director, Clinical Research, associate director, Clinical Research, codirector, Gastrointestinal Cancer Program, medical director, Judy & Bernard Briskin Center for Clinical Research, City of Hope, discusses the main objective and design of the observational BASECAMP-1 study (NCT04981119), and how it functions alongside the phase 1/2 EVEREST-1 study (NCT05736731) in patients with solid tumors.

The ongoing EVEREST-1 study is assessing the efficacy of the novel Tmod CAR T-cell therapy A2B530 in patients with recurrent unresectable, locally advanced, or metastatic carcinoembryonic antigen (CEA)-expressing solid tumors with HLA-A*02 loss of heterozygosity. To be eligible for enrollment on EVEREST-1, patients must undergo extensive screening in the non-interventional BASECAMP-1 study.

The BASECAMP-1 study was designed to identify patients with human leukocyte antigen (HLA) loss of heterozygosity who may be optimal candidates for treatment with A2B530, as well as to increase understanding of how the loss of HLA heterozygosity might occur, Fakih states.

The first step in the screening process will be to perform HLA typing on patients with solid tumors, he details. Those identified as HLA-A*0201-positive who have malignancies that are expected to be CEA producing, will have their tumors tested for loss of heterozygosity of HLA-A*0201, Fakih describes. Potential CEA-producing malignancies include colon cancer, pancreatic cancer, and non-small cell lung cancer, he adds.

After screening patients for HLA-A*02 loss of heterozygosity, patients with both HLA-A*0201-positivity and a loss of heterozygosity will undergo apheresis to collect and store T cells for future A2B530 production, Fakih continues. Approximately 30% of the overall population is expected to be HLA-A*0201-positive, he says. Of these patients, about 15% to 20% are predicted to be candidates for apheresis.

Patients have the option to resume treatment with standard-of-care (SOC) regimens after the completion of apheresis, provided it continues to be effective, Fakih notes. Eligible patients who experience disease progression on their SOC therapy in BASECAMP-1 will be enrolled onto EVEREST-1 and their stored T cells will be used to manufacture A2B530, Fakih states.

Employing this trial design allows physicians to develop CAR T-cell therapy ahead of patient progression, reducing delays. It also enables them to determine the optimal time to proceed with CAR T-cell therapy, Fakih concludes.