Measuring success in clinical gene therapy research.

Medical science is a compelling career choice, filled with the thrill of discovery, joy of learning and a meaningful purpose to lessen human suffering. These benefits and rewards of laboratory and clinical research accumulate in an asynchronous, irregular, and incremental mechanism, euphemistically known as the scientific method. Ultimate success in clinical research is the elusive 'cure'. But in progress towards that goal, success is also measured first as the 'absence of doing harm', and then by various stages of efficacy. Perhaps only in the case of smallpox has medicine achieved total 'victory'; it is now exactly 200 years since Jenner's first clinical trial.