Scientists envisioned administering genes like penicillin, insulin and other drugs to treat and cure disease. Then it began to yield to a more sober realization of the difficulties involved in getting genes into diseased cells and getting them to work. Anderson, a human gene therapy pioneer while at the National Institutes of Health, counted more than 300 clinical trials approved worldwide for gene therapy of cancer and other diseases since 1990. Now he's with the University of Southern California at Los Angeles. The results clearly indicate that gene therapy has potential for treating cancer, heart disease, AIDS, hereditary disease and other conditions.
Gene therapy is attractive because it seems to cause few adverse reactions.
Scattered reports do exist in which a few individual patients apparently were helped, he said. But an analysis of all the gene therapy approaches, or protocols, used in clinical trials tells a different story. Anderson looked at data on 232 clinical trials that had been approved in the United States as of February 1998. The biggest and most advanced clinical trial involves 246 patients with glioblastoma, a deadly form of brain cancer. It's a so-called Phase II clinical trial, the final phase before a drug company can apply for Food and Drug Administration permission to market a drug.