A new study describes a CAR T approach aimed at fusion-driven solid tumors using GPNMB as the target antigen. The research extends the CAR T playbook beyond hematologic malignancies by focusing on tumor biology linked to fusion-associated mechanisms, which are often associated with aggressive behavior and treatment resistance. The report emphasizes how the next frontier for CAR T will likely depend on selecting antigens and tumor contexts where engineered T cells can persist, traffic, and function without being neutralized by the microenvironment. While still early in the pipeline, the work adds a potential strategy for building solid-tumor CAR T designs around disease-specific drivers rather than broad surface marker targeting alone.