Why Other Cancer Vaccines Won't Follow in the Footsteps of Dendreon's Provenge

Last Updated May 10, 2010 11:12 AM EDT

Dendreon footstepsDendreon's (DNDN) historic approval last month of prostate cancer vaccine Provenge (sipuleucel-T) sparked a flurry of interest in other cancer vaccine companies. But none of them are poised to follow in Dendreon's footsteps anytime soon.

Provenge's approval marked the first time the FDA has ever cleared a vaccine to treat cancer, so the excitement about the "Holy Grail of oncology" and a "new era in medicine" was understandable. But some folks took the excitement a bit far, as evidenced by two press releases from Mentor Capital proclaiming that:

...the featuring of Dendreon's Provenge prostate cancer vaccine on Fox News is a certain sign that cancer immunotherapy has come to a point of popular acceptance in the public mind. ...there is no reason to believe similar cancer immunotherapy treatments would not then be similarly safe, effective and, in due course, approved.
Um, not exactly. Yes, several other cancer vaccine companies saw their stocks pop on Provenge's approval, including Antigenics (AGEN), AVAX Technologies (AVXT.PK), Biovest International (BVTI.PK), Celldex (CLDX), ImmunoCellular (IMUC.OB), Oncothyreon (ONTY), Vical (VICL) and others. But none of those gains were sustained. Here's why.

First, the cancer vaccine field has a long history of failure, and many of the companies closest behind Dendreon carry a lot of baggage. Antigenics failed in Phase III, AVAX is limping along on bridge loans while it tries to finish its Phase III trial, Biovest is struggling to emerge from bankruptcy and its data have raised plenty of questions, Oncothyreon's Phase III program is on hold. Etc., etc., etc.

Which isn't to say that baggage can't be overcome. Dendreon failed its first Phase III trials with Provenge and look where it is today. But that makes it the exception, not the rule.

And here's the second part of the equation. Although cancer vaccines get lumped together as a single mechanism, they encompass many approaches. Whether you go personalized or off-the-shelf, antigen-based or whole cell, lung or breast cancer, with an adjuvant or without, in combination with the standard of care or alone, aiming at progression-free survival or overall survival... all of these things can impact success.

All of which means that while Dendreon's Provenge approval does provide validation for the cancer vaccine field, any followers still have a fair amount of trailblazing to do on their own.

Footsteps photo by Flickr user VinothChandar(AWAY), CC.

  • Trista Morrison

    Trista Morrison is a staff writer at BioWorld Today, a daily newspaper that