NEW YORK--Pharmaceutical companies are currently investigating
25 new treatments for prostate cancer, including a potential vaccine,
Alan Holmer, president of the Pharmaceutical Research and Manufacturers
of America, said at a media briefing conducted by the American
Cancer Society and the New York City-based Cancer Research Institute.
Along with new agents in the pipeline for prostate cancer are
new applications and different formulations of older drugs, said
medical oncologist Gene Resnick, MD, vice president for clinical
research, Schering-Plough Research Institute.
A new use of existing agents is the combination of flutamide (Eulexin)
and a luteinizing hormone-releasing hormone agonist (LHRH-A) in
early-stage prostate cancer. In another approach, flu-tamide plus
finasteride (Proscar) is being studied for use in advanced or
recurrent prostate cancer.
Established chemotherapeutic agents are also being studied in
new applications and combinations; for example, mitoxantrone (Novantrone)
in combination with prednisone for palliation of advanced hormone-refractory
prostate cancer (see also page 4); fluorouracil with cisplatin
(Platinol) in refractory metastatic disease; and flutamide with
epiru-bicin in advanced prostate cancer.
A new liposomal form of doxorubicin is in development, and other
liposomal products are in the works, he said, as are potentially
more effective hormonal agents, including new LHRH antagonists
and agonists, new antiandrogens, and other investigational drugs
such as liarozole and the synthetic retinoid fenretinide.
Dr. Resnick is particularly excited by efforts to develop biological
response modifiers and gene therapy techniques for use in prostate
and other cancers. For example, a signal transduction inhibitor
being developed at the National Cancer Institute changes the calcium
flow in each cell and may have some application in prostate cancer.