Aggressive Parkinson's Treatment Falls Short

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In the complex and often esoteric world of medical research, it helps to remember that the road to triumph is paved with disappointment. Thursday, another such disappointment appeared in the pages of the New England Journal of Medicine.

According to researchers at the University of Colorado and Columbia University, the results of a daring procedure designed to ameliorate the symptoms of Parkinson's disease have fallen well short of expectations. While some of the human test subjects did experience a brief respite from the tremors and loss of balance associated with Parkinson's, a progressive neurological disease, most were unaffected or adversely affected by the experimental procedure.

Test subjects were divided into groups, one of which received transplanted cells from aborted fetuses via holes drilled into the patients' skulls. The other patients had mere indentations drilled into their skulls, to mimic the real procedure. This experiment represents one of the fastest-growing and most controversial areas of clinical research: The use of stem cells has prompted widespread, fierce debate, pitting research proponents against some medical ethicists and pro-life groups.

Dr. Ira Shoulson, a professor of neurology at the University of Rochester in upstate New York, also chairs the nonprofit Parkinson's Study Group, which investigates and oversees clinical trials for new Parkinson's treatments. Dr. Shoulson spoke with Thursday about the study and pointed out a silver lining in the otherwise bleak results.

In the media, anyway, this study will be painted as a failure. Do you think, beyond all the bad press, that this has a larger significance for Parkinson's research in general?

Shoulson: Of course. Look, this study, and another, similar study that's going on right now, are very important undertakings for at least two reasons. One, this is a very promising area of research. And two, these studies are done in a systematic, rigorous and controlled fashion — and that's very important for future research.

This is a first step. This procedure is far from ready for clinical use; it fell short in several areas. In older patients, for example, it had no benefit at all. In younger subjects, there was brief but fleeting improvement. All of the surgical patients experienced serious side effects — and of course four of the subjects developed runaway movements and tremors as a result of an overproduction of dopamine.

Research using stem cells, which are often harvested from aborted fetuses, sparks heated debate in political circles and among medical ethicists. Tommy Thompson, the new secretary of Health and Human Services, has indicated he will not try to stop stem cell research, even though he is pro-life. Is there any concern among the scientific community that negative results like these might result in fewer federal funds earmarked for stem cell research projects?

Shoulson: No. I don't think we need to be worried about that. My feeling is that in terms of advancing therapeutic treatments, the real issue is not where the cells come from, but where they're going, both in terms of where the cells go physically and in terms of where the whole route of study goes from here.

The positive aspect of this research is that it provides a critical view of stem cell treatments. We need to continue to develop these treatments, and we can't use stem cells without data and without a reasoned approach, which this study helps provide.

This study also weathered a lot of criticism because it used sham surgery — a procedure in which one group of subjects just had slight indentations drilled into their heads — to create a control group. Can you answer those critics?

Shoulson: There's been a lot of debate as to whether sham surgery is ethical — my feeling is that it's unethical not to use the sham procedure. By using a control group, we are closer to a real answer, not just to affirming whatever we wanted the answer to be.

Before this experiment, this procedure was widely considered the best thing since sliced bread — and without a carefully structured study, which must include a control group, we wouldn't have known about the very serious drawbacks to this procedure.