UPDATED: Dendreon's Provenge faces new questions

Will the rough news for Dendreon ($DNDN) ever stop?

Even as its sole product, prostate cancer drug Provenge, faces competition from Johnson & Johnson's ($JNJ) Zytiga, a new attack on its effectiveness has been launched by a former hedge fund manager on a mission.

Marie Huber, a former analyst who also has degrees in biochemistry and bioscience enterprise from Cambridge, had a paper published last month in the Journal of the National Cancer Institute. It argues that the trials may have been affected by a placebo that was actually harmful to those taking it, reports Reuters. She took up the cause seeking intellectual rewards, not financial gain, and Reuters says she has never held a position in Dendreon.

Update: SEC: Provenge critic lied about her bets Dendreon stock would fall.

The company dismisses her findings and says the somewhat controversial treatment has saved the lives of thousands of men. In a statement sent out late Friday by Dendreon spokeswoman Tricia Larson in response to all of the publicity the Journal article was receiving the company pointed out the FDA's approval of the treatment was based on "a significant improvement in overall survival." It says the clinical data came from 'three well-designed, randomized, double-blind, controlled clinical trials – including the pivotal IMPACT trial."

Provenge is a vaccine that engineers white blood cells to fight cancer. But it is expensive, at $93,000 a year for treatment. Reuters points out that it also has not lived up to its initial promise financially. Dendreon's 2011 product revenues were $213.5 million, a far cry from the $400 million in sales that had been projected from the drug.

Earlier this month, Johnson & Johnson reported that its prostate cancer pill Zytiga has shown itself effective in patients who haven't yet received chemotherapy, putting it in competition with Provenge.

- check out the Reuters story