This study is being conducted to evaluate how the body processes a specific medication during a certain type of preparation for advanced cancer treatment. The research focuses on patients with a hematological malignancy, which is a type of cancer that affects the blood or bone marrow, who are preparing for CAR-T cell therapy. This advanced treatment involves using specially modified immune cells to fight cancer. Before receiving these modified cells, patients undergo lymphodepletion, a process using medications to reduce the number of certain white blood cells to make the treatment more effective.

The treatment being studied involves the use of fludarabine phosphate, which is administered through an intravenous line, meaning it is delivered directly into a vein. This medication is used alongside cyclophosphamide as part of the preparation process. The study also takes into account patients who have previously received or are scheduled to receive other specialized cell therapies, such as tisagenlecleucel, axicabtagene ciloleucel, brexucabtagene autoleucel, or ciltacabtagene autoleucel. The goal is to understand the pharmacokinetics, or how the drug moves through, is absorbed by, and is eliminated from the body.

During the course of the study, blood samples will be collected to measure the levels of the medication in the blood over time. These measurements help determine the maximum observed concentration and the overall exposure to the drug. Researchers will also look at various patient factors, such as weight and kidney function, to see how they might relate to how the body handles the medication.