Ella Does Squamish

from http://pharm-aid.blogspot.com/2007/07/behind-scenes-of-provenge.html

Friday, July 6, 2007
Behind the Scenes of the Provenge

The decision by Howard I. Scher of the venerable Memorial Sloan-Kettering Cancer Center and Maha Hussain of the University of Michigan to vote against approval of Dendreon’s cancer vaccine, Provenge, at a recent FDA Advisory Committee received some major attention in today’s Washington Post. The doctors are claiming they are fearful for their safety because of patient advocates.

Patient advocates have certainly launched an offensive against the decision to withhold approval. Depsite following the trial protocol that was agreed to with the FDA, the outcomes were uncertain. Provenge appears to have minimal adverse events, but the benefits are not entirely clear…at least in the short term. The drug has clearly worked for some. And the hope that it will work for others is leading patient advocates to push for approval. Standing in the way of new treatment for prostate cancer are Drs. Howard I Scher and Maha Hussain. Their reasons for voting against approval are far reaching and include lack of achieving certain endpoints, lack of clarity on other endpoints, and perhaps reasons that are less clear.

Much has been made in today’s Washington Post and in online message boards of the doctor’s relationships with competing companies. When I first started researching this, I figured it was going to be a whole lot of nothing. Many researchers have relationships with numerous firms. It’s not uncommon and I would have been surprised to learn that the doctors had no relationships.

True to form, according to government disclosures, Howard I. Scher either currently or has owned stock in Genta (which is developing the Genasense technology). He has acted as a consultant to Sanofi-Synthelabo (now sanofi-aventis; which has its own cancer vaccine program). And has accepted more than $2,000 from AstraZeneca and Aventis. At face value, this really isn’t news and seemed to be patient advocates getting worked up over nothing.

However, I then noticed that both Scher and Hussain are investigators in trials for Novacea’s Asentar, a potentially rival prostate cancer treatment. And less than a month after their vote against Provenge, Novacea inked a major deal with Schering-Plough to market the product. Had the FDA just approved a potentially rival product like Provenge, what would that have done to the value of the deal? Everyone can draw their own conclusions, but all I will say is that this is a case of remarkable timing.

The whole Provenge mess really shines a light on the clinical trial process for all of the cancer vaccines. The clinical trials tend to be quite long and involved. In the early days, it was not uncommon for the standard of care to be different by the end of the trial than it was at the beginning. Companies began engaging in Special Protocol Assessment Agreements with the FDA to stop the process of being held to one standard at the end of the trial than they were at the beginning. It is critical that the FDA needs to figure out how it will evaluate cancer vaccines and then stick to that standard.

Posted by UDW at 11:50 AM

Labels: Cancer Vaccines, Dendreon, FDA, Genta, Novacea, Oncology, Sanofi-Aventis, Schering