Health

Ethical Problems for Gene Therapy

By CBSNews.com staff CBSNews.com staff

January 31, 2002 / 8:40 AM EST / CBS

News tonight about a gene-research controversy that CBS News has been reporting in-depth: the risks to patients who receive experimental gene therapies designed to treat diseases. Medical Correspondent Elizabeth Kaledin has been digging into the latest revelations.

In the field of gene therapy Dr. Jeffrey Isner is a leading force. His experiments manipulating genes to reverse heart disease are on the cutting edge and his results have been promising. But even he admits it's risky business.

Isner says "there are certain risks we're taking as doctors and investigators here, but the real risks are being taken by the patients."

Now, after investigating Isner's research and shutting it down, the FDA has determined he was taking a few too many risks, knowingly enrolling a patient in his study who had cancer.

This revelation has prompted a warning letter from the FDA that says that Isner "did not fulfill your obligations as a clinical investigator." The letter also accuses him of "a serious lack of study oversight."

In Isner's experiments, genes that promote blood vessel growth are injected into patients' failing hearts--to improve blood flow. But in a patient with cancer, the same genes that create blood vessel growth can also cause tumor growth.

Gene therapy ethicists are at a loss to explain how anyone with cancer would have been in Isner's study.

"If someone is supposed to be excluded because of reasons of safety and they end up being included...that's a terrible ethical violation," says Dr. Ruth Macklin, a gene therapy ethicist.

Compounding Isner's ethical dilemma is that he is invested in the company backing his research--Vascular genetics.

Isner will not comment. The FDA has given him 15 days to respond to it's warning. In the meantime, what was promising research has been derailed--both by an apparent disregard for patient safety and by a growing lack of public confidence in gene therapy.