The only results that have been made public are from the incomplete testing of Genasense combined with decarbazine. Other tests using other chemo treatments may be continuing, among them, use of Genasense for breast cancer (at the Andersen Center in Houston).
A great deal of research has gone into Genasense and the results, while still not conclusive, are promising. If the results had NOT been promising, the company would probably have abandoned its research altogether. The reearch, after all, has been going on for at least five years. Similar research is currently being carried out with related antisense compounds produced by AVI Biopharma and ISIS. If antisense were a bust, then you wouldn't see as much continuing activity.
For the sake of comparison, Genentech brought out the first great product of gene splicing--Tissue plasminogen activase--for treating blood clots in the heart some 20 years ago. Doctors who had participated in the clinical trials thought the drug was marvelous. It worked better and quicker than anything else, even though the results were not much better than one would expect from a competing natural product, or even aspirin. Publicity about the marginal effectiveness of TPA literally crushed the company, forcing it into an alliance with Roche in order to obtain enough cash to survive. Eventually TPA became an accepted treatment, but the costs incurred in its development, combined with a limited market (insurance companies rarely would cover its use, since there were cheaper alternatives that were deemed almost as good) meant that TPA was and is a very expensive treatment.
Genta may be forced into some kind of alliance with another stronger company, which is why the stock may take a long time to recover, even if Genasense eventually proves useful. But treating heart attacks, for which several treatments are available, is different from treating a terminal cancer patient, where virtually nothing out there works well. There is a great deal of motivation to use something--anything that looks promising. As more data are collected from continuing trials of Genasense, it will become increasingly difficult to deny approval if there is even only a slight chance of the drug being effective. A denial carries with it not only health implications but political impacts.
Finally, having studied other trials of antisense compounds, I would dispute the notion that Genasense may produce undesirable side effects. It has not been proved that the undesirable side effects in the decarbazine study were caused by Genasense making decarbazine MORE effective, thereby allowing for lower dosages. In other words, it is likely that antisense drugs in general have few undesirable side effects (they either work, or they just pass through the body without any effect). But we know that one of the properties of antisense treatment is to reduce the body's intolerance of a standard chemo treatment, making the chemo more effective for a longer period, at a lower dose. If the dose of the chemo remained at the high level prescribed for the chemo alone, then the effect of the chemo and Genasense together could have produced an overdose condition, with heightened undesirable side effects.
As Yogi Berra said, "It ain't over till it's over!"
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