Why CAR T therapy works for some patients but fails for others may be getting clearer

Chimeric antigen receptor (CAR) T-cell therapy is one of oncology's most powerful ideas: Harvest a cancer patient's own immune cells, genetically engineer them to recognize tumor cells, multiply them in a laboratory and reinject them as a living drug. For some patients, the treatment produces extraordinary, durable remissions. For many others, however, it produces nothing, but new research sheds light on the reason.