Stable Ethics: Enrolling Non-Treatment-Refractory Volunteers in Novel Gene Transfer Trials

Abstract

The vast majority of human gene transfer experiments have been tested in patients suffering from advanced, treatment-refractory diseases. Until recently, some jurisdictions actually restricted gene transfer trials to disorders that are life threatening or cause serious handicap and for which treatment is either unavailable or unsatisfactory.1 However, some of the best opportunities for advancing knowledge have involved diseases for which standard, if suboptimal, medical interventions are available. One example is adenosine deaminase–severe combined immunodeficiency disease, which has been tested in subjects whose disease is controlled by enzyme replacement. Another is hemophilia, which has been tested in subjects eligible for factor replacement. Other diseases that have been (or might be in the near future be) targeted in gene transfer protocols, but that can be medically controlled, include 1-antitrypsin deficiency, Gaucher's disease, recent-onset type 1 diabetes mellitus, arthritis, and early-stage Parkinson's disease.