Today's announcement that the U.S. Food and Drug Administration has approved Provenge®, a new form of therapy for some prostate cancer
patients, marks the beginning of an era in which patients' own immune
systems become part of the standard therapeutic arsenal against cancer,
say Dana-Farber Cancer Institute investigators who led a study of the
treatment's effectiveness in patients.
The study — the results of which were presented most recently at the
2010 Genitourinary American Society of Clinical Oncology's annual
meeting — is the first large, controlled clinical trial to show that an
immune system-based therapy can extend the lives of cancer patients,
according to the trial's leader, Philip Kantoff, MD, of Dana-Farber.
"For more than 20 years, scientists have been working on harnessing
the immune system in a way that has beneficial effects for cancer
patients, notably the prolongation of survival," Kantoff said. "Our
study provides proof that such an approach can work."
Unlike preventive vaccines, which bolster the immune system to
protect people from contracting an illness, Provenge is an "autologous
cellular immunotherapy," or a therapeutic vaccine, that marshals the
immune system's disease-fighting forces for people who already have
The immunotherapy is produced by removing some of a patient's white
blood cells — a process called leukapheresis — and then exposing them to
a protein from prostate cancer cells and a stimulatory molecule. The
process primes the white blood cells to stimulate the immune system and
attack prostate cancer when they are re-injected into the body.
The clinical study, a Phase III trial conducted at cancer treatment
centers across the country, enrolled 512 patients with advanced prostate
cancer that had spread beyond the prostate gland and that grew even
when deprived of the hormone androgen, a condition known as metastatic
hormone-resistant prostate cancer.
Patients were randomly assigned to receive either Provenge, which is
manufactured by the Dendreon Corporation of Seattle, or an inactive
Philip Kantoff, MD
Compared to the placebo, Provenge extended a patient's median
survival by 4.1 months, improved three-year survival by 38 percent, and
reduced the overall risk of death by 22.5 percent.
Approval by the FDA means that Provenge will become available within
the next year to prostate cancer patients who meet the criteria of
having advanced, metastatic tumors that are hormone resistant.
Because of the complexity of making the immunotherapy — which must be
individually produced for each patient — there will be a six- to
12-month ramp-up period before it is available to all eligible patients.
Patients should check with their doctors to determine if they're
candidates for the vaccine, noted Kantoff, who is the director of the
Lank Center for Genitourinary Oncology at Dana-Farber/Brigham and
Women's Cancer Center, chief of the Division of Solid Tumor Oncology and
chief clinical research officer at Dana-Farber, and professor of
medicine at Harvard Medical School.
Every year, more than 192,000 men are diagnosed with prostate cancer
in the United States, and more than 27,000 die of the disease, according
to the American Cancer Society. The number of men with metastatic,
hormone-resistant prostate malignancies who might benefit from Provenge
is in the tens of thousands.
Provenge is administered to patients three times over the course of a
month. It is designed to fit in with other treatments that patients
may be receiving.
"As scientists have learned more about the basic workings of the
immune system, they've developed increasingly effective ways to exploit
the immune response to cancer," Kantoff said.
"Provenge is the first fruit of this endeavor to receive FDA approval
— the first of what we expect to be many more cancer immunotherapies in
"We are beginning to see the results of years of research into the
basic biology of cancer, and of our work to personalize care around the
unique characteristics of each patient," said Edward J. Benz, Jr., MD,
president of Dana-Farber.
"These promising results are a step forward in a long journey."
Dana-Farber Cancer Institute (www.dana-farber.org)
is a principal teaching affiliate of the Harvard Medical School and is
among the leading cancer research and care centers in the United States.
It is a founding member of the Dana-Farber/Harvard Cancer Center
(DF/HCC), designated a comprehensive cancer center by the National
Cancer Institute. It provides adult cancer care with Brigham and Women's
Hospital as Dana-Farber/Brigham and Women's Cancer Center and it
provides pediatric care with Children's Hospital Boston as
Dana-Farber/Children's Hospital Cancer Center. Dana-Farber is the top
ranked cancer center in New England, according to U.S. News & World Report,
and one of the largest recipients among independent hospitals of
National Cancer Institute and National Institutes of Health grant