Deaths force halt to Cell Genesys cancer vaccine trial

A closely watched trial for Cell Genesys' prostate cancer vaccine GVAX was brought to a sudden halt after an independent monitoring committee noted a significantly higher death rate in the group taking a combination of the vaccine and Taxotere compared to the control arm of the study. In a statement, Cell Genesys said that 67 patients taking the combo therapy had died compared to 47 who were taking Taxotere alone. The company said it doesn't know why the vaccine group would experience a higher rate of death.

Investors weren't waiting for details. The news quickly wiped out 70 percent of the company's share price, leaving it at 85 cents this morning and pointed downward. The committee will now examine the death rate in a separate trial of GVAX called VITAL-1. In January, the committee gave researchers a green light to continue with that trial.

- check out the Cell Genesys release
- read the AP report