FDA backs prostate cancer therapy

Dendreon Corp.’s Provenge vaccine trains the immune system to fight tumors. It’s called a vaccine even though it treats disease rather than prevents it. Doctors have sought to develop such a therapy for decades. Provenge is the first to win Food and Drug Administration approval.

“I suspect within five to 10 years immunotherapies will be a big part of cancer therapy in general,’’ said Dr. Phil Kantoff, an oncologist at Dana-Farber Cancer Institute in Boston who helped run the studies of Provenge.

Experimental vaccines to treat other cancers — including the deadly skin disease melanoma and an often fatal childhood tumor called neuroblastoma — are in late-stage development.

Currently, doctors treat cancer by surgically removing tumors, attacking them with chemotherapy, or blasting them with radiation.

The treatment is intended for prostate cancer that has spread elsewhere in the body and is not responding to hormone therapy.

Medical specialists hailed the approval as a milestone, but stressed the therapy be an addition to current medical practice, not a replacement.

“This is just one step in a new pathway for treating patients,’’ said Dr. Simon Hall, chairman of urology at Mt. Sinai Hospital.

Company studies showed taking Provenge added four months to the lives of men with advanced prostate cancer — more than the three months afforded by Taxotere, the only chemotherapy approved for men in this situation. Doctors hope for greater benefit if they give the drug earlier in the course of the disease.

Dendreon said yesterday that the drug will cost $93,000 per patient.