Expanded distribution of an investigational drug in parallel with ongoing controlled clinical trials: the didanosine model.

The purpose of the didanosine Expanded Access Program was to provide a needed antiretroviral agent to individuals who were unable to tolerate other therapy for human immunodeficiency virus infection or in whom such therapy was failing. The logistics of establishing this program are described, and the results of on-site auditing that confirmed the validity of the data obtained through this program are presented.