Most prominently, teenager Jesse Gelsinger died from multiple organ failure a few days after receiving a massive dose of virus-based gene therapy in a trial at the University of Pennsylvania.

FORBES: Glaxo Brings Gene Therapy Back From The Dead

Consider, for example, the reactions of the European Medical Agency (EMA) and Health Canada to the report of the unexplained death of a U.S.-based patient less than 24 hours after receiving the first dose of Gilenya, a relatively new oral treatment for multiple sclerosis.

FORBES: The Data On Drugs' Side Effects Must Be Reliable