WASHINGTON - The FDA on Friday sent a scalding warning letter to the University of Pennsylvania's Institute for Human Gene Therapy, completely rejecting IHGT's Feb. 14 self-exculpatory response to the agency's investigation into the death of Jessie Gelsinger in a gene therapy trial. The agency extended its suspension of all gene therapy research at U Penn for an indefinite period and told the university to respond to the warning letter within 15 days.

The letter also informed James Wilson, the institute's director and principal investigator in the trial, that his "activities as a clinical investigator will be discussed in a separate letter."