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64Cu-DOTA-pembrolizumab PET for the Study of PD1 Expression

Trial Status: withdrawn

This phase I trial evaluates the best dose and side effects of copper (64Cu)-DOTA-pembrolizumab positron emission tomography (PET) for the study of PD1 expression. 64Cu is a radiotracer that binds to a molecule, PD1, that is found on immune cells that are found in the tumor. PD1 is short for ‘programmed cell death protein 1’. When 64Cu-DOTA-pembrolizumab is injected into the patient’s bloodstream, the 64Cu-pembrolizumab travels throughout the body and sticks to any tumor that has PD1 positive immune cells. Identifying the expression of PD1 in the tumor may help assess whether patients will respond to immunotherapy, and may detect clusters of immune cells when they are still too small to be detected by other Food and Drug Administration (FDA) approved techniques.