Commentary. The normal volunteer in clinical investigation: how rigid should selection criteria be?

Twenty-nine healthy young male volunteers were screened by history, physical examination, urinalysis, 24 different blood tests, and electrocardiography for admission to a Phase I drug study. The protocol submitted to, and approved by, the FDA listed the normal ranges for the local laboratories and stipulated that the test results for any volunteers accepted should all be within these ranges. During screening 46 abnormal values were found in the laboratory tests. Only 4 subjects had all their test data within "normal" range, a result that could have been anticipated simply form the number of tests performed. These findings indicate the need for deciding on realistic protocol criteria for studies involving healthy volunteers.