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Transplanting Risk

by Jeffrey P. Kahn, Ph.D., M.P.H.
Director, Center for Bioethics
University of Minnesota

A stunning research result was reported recently in the New England Journal of Medicine. In the first controlled trial of an approach to treat Parkinson's disease, patients were recruited to participate in research to assess the effectiveness of human fetal nerve cells transplanted into the area of the brain affected by the disease. Unfortunately, the results were not what researchers or subjects expected.

Instead of seeing their symptoms end, many subjects either didn't see any improvement or experienced a worsening of symptoms so severe that they were reduced to lying in bed with their limbs flailing uncontrollably. Even patients who did see some improvement suffered severe side effects.

Researchers need to investigate the reasons for these results, but one possible answer is that the implanted nerve cells were performing too well and producing too much of the brain chemical that's missing in patients with Parkinson's. Unfortunately, once the cells are implanted they can neither be removed nor controlled. Patients who once suffered from the limitations of the disease ended up far more disabled as a result of their research participation.

Focusing on the benefits of research

It is natural that patients with such a disease would clamor to be in research that proposed to cure it, but few expect that they could be grievously harmed in the process. The way the neural cell transplant trial was conducted fueled such expectations. The researchers divided subjects into two groups -- one had the cells injected into their brains through holes drilled in their skulls, while another had the holes drilled, with no cells implanted. This allowed researchers to compare outcomes between the two groups without subjects knowing whether or not they received the transplants. Subjects were promised that if they were randomized into the group that did not receive the implanted cells, at the end of the trial they would be offered the option of having the implants -- an implicit promise that they too, would receive the benefits of the research.

Remembering what research means

The prospective benefits of research are only half of the picture, as the outcome of this research reinforces. In research in general, we don't know whether a new approach will work but we do know that it has risks and side effects -- some of them unknown, all of them uncertain. Research relies not on the willingness of subjects to avail themselves of the benefits it has to offer, but on their willingness to put themselves in harm's way so that others may benefit. If subjects receive some medical benefit in the process, it's frosting on the cake. But prospective subjects often don't see things this way, and having their unreasonably high expectations dashed can undermine support for research.

The story should serve as a wake-up call for the biomedical research community as well as all of us who participate in and benefit from research -- which means just about everyone. Increasingly, cutting edge research doesn't necessarily mean risk-free research, or research that will always work the way we hope and predict. That doesn't mean we shouldn't do research. But we should have more realistic expectations for what benefits research holds and be more realistic about the costs for achieving them.

Visit the
"Ethics Matters" Archive
where you'll find other columns from Jeffrey Kahn
on a wide range of bioethics topics.

"Ethics Matters" is a biweekly feature from the
Center for Bioethics and CNN Interactive.


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