No Devil in Details: Dendreon Data Stands Up to Scrutiny from Doctors, Investors

Suspense has been building for two weeks about just how good Dendreon’s big clinical trial results were going to be, and when the results finally came out today, fans of the company had nothing to be disappointed about.

Earlier in the day, we reported what readers needed to remember about the context of this trial, and then we reported the most essential facts when the data appeared. A clinical trial of 512 men, called Impact, showed that patients lived a median time of 25.8 months if they got Provenge, Dendreon’s experiemental immune-booster, compared to 21.7 months for those on a placebo. This finding represents a 4.1 month advantage in median survival on the drug. The p-value, which tells statisticians whether this might have been due to chance, was 0.032, which is well within the FDA’s threshold to certify the finding as legitimate. Side effects were mostly fever and chills that lasted one or two days after injections.

Dendreon provided much more extensive detail on this trial in a conference call today with analysts, but there was nothing groundbreaking or revelatory beyond what David Penson of USC presented earlier in the day at the American Urological Association meeting in Chicago. Dendreon CEO Mitchell Gold didn’t back off at all from his statement a couple weeks ago that the data was “unambiguous” and a “clear hit.” But I felt the need to follow up with this story to provide a few more details and look ahead at some of the business strategies that will become more important as this year goes on.

This trial matters more than most, and generates way more headlines, because it is the first time after decades of research that scientists have shown an ability to stimulate the immune system to fight cancer cells like a virus. This new mode of treatment is called an immunotherapy, or sometimes a cancer vaccine. It’s also a big step forward for treatment of prostate cancer, which kills about 30,000 men every year in the U.S., and is currently treated with chemical castration, and in the terminal stages, a form of chemotherapy called docetaxel (Taxotere) that has nasty side effects most men would prefer to avoid. Some people balked at why trading in the stock suddenly fell 45 percent before the announcement, but there was nothing in the data to explain why that happened. After hours, the shares recovered, climbing to $27.22 a share, according to this Bloomberg News story. One doctor told the Wall Street Journal that “We’ve been waiting a long time,” for a drug with a profile like Provenge.

“This is a historic day for the company, and a great day for prostate cancer patients,” Gold said.

So Provenge has been eagerly anticipated by patients for years. Chief medical officer Mark Frohlich walked through most of the data on the call for analysts. Here are the highlights:

—Patient demographics in terms of age, race, and tumor status were about the same among patients who were randomly assigned to get Provenge or a placebo when they entered the study. That means

Author: Luke Timmerman

Luke is an award-winning journalist specializing in life sciences. He has served as national biotechnology editor for Xconomy and national biotechnology reporter for Bloomberg News. Luke got started covering life sciences at The Seattle Times, where he was the lead reporter on an investigation of doctors who leaked confidential information about clinical trials to investors. The story won the Scripps Howard National Journalism Award and several other national prizes. Luke holds a bachelor’s degree in journalism from the University of Wisconsin-Madison, and during the 2005-2006 academic year, he was a Knight Science Journalism Fellow at MIT.