A September 20, 2026, science roundup describes a comparison of 50 patients treated with cilta-cel and 37 treated with ide-cel. It says cilta-cel showed roughly tenfold greater peak expansion and a stronger GZMK-positive T-cell program. The post also describes mouse experiments in which swapping the promoter that drives CAR expression reproduced much of the difference without changing the antigen-binding domain—the part that recognizes the target. It cautions that the clinical comparison was not randomized and that the promoter mechanism still needs direct human validation.