This is the story of how a monitoring only rescue team caught a silent PK problem before it damaged a Phase 1 CAR-T data package and persistent pattern recognition kept a complex trial on track. What first looked like a few isolated sample issues quickly resolved into a pattern: time sensitive PK samples were arriving invalid at one of the four participating sites in a rare population, first in human (FIH), Phase 1 CAR-T trial. For a modality where every patient matters, every draw matters, and