The Food and Drug Administration (FDA), for the first time, gave permission for clinical trials on humans of therapy derived from embryonic stem cells. The study will be financed by Geron Corporation, based in Menlo Park, California. Ten years ago, Geron financed the research at the University of Wisconsin that first isolated embryonic stem cells. The trial will involve 8 to 10 patients with severe spinal cord injuries. Geron’s application to the FDA was 21,000 pages long and included details from 24 separate animal studies.