Taxotere® Evaluated for Treatment of Hormone-Dependent Prostate Cancer.
Researchers from the University of Medicine and Denistry of New Jersey/Robert Wood Johnson Medical School have reported that Taxotere® (docetaxel) is well tolerated and effective in men with PSA progression after completion of local therapy. The details of this phase II study were reported in an advanced publication of the Journal of Clinical Oncology.
Recent studies have suggested that hormone-refractory prostate cancer is sensitive to chemotherapy. However, the use of chemotherapy in the treatment of prostate cancer has historically been met with some resistance because clinical trials failed to document an improvement in survival. Currently, only three drugs, Taxotere®, Emcyt® (estramustine) and mitoxantrone, are FDA-approved for the treatment of prostate cancer. Recent publications suggest that Taxotere® alone or combined with Emcyt® with or without prednisone may be the optimal treatment of hormone-refractory prostate cancer. There is limited experience with the use of chemotherapy in patients with hormone-sensitive disease. However, this is a logical extension following the demonstration of effectiveness in hormone-refractory disease. Chemotherapy may have many unpleasant side effects but androgen ablation is also not without significant morbidities.
These researchers treated 25 men who had PSA increases of at least 50% for 4 weeks. Prior therapy had consisted of vaccine therapy in 4, mitoxantrone in 10, 13-Cis retinoic acid/interferon alfa in 3 and tamoxifen/P30 protein in 5. The following table summarizes the main findings of this clinical trial.
Table 1: Effect of Taxotere® on Men with Hormone-Dependent PSA Progression
Number of Patients 25
Mean age (range) 64 years (36-77)
PSA decrease 18
PSA progression 5
PSA decrease 50% or greater 43%
PSA decrease 75% or greater 135
These authors reported that Taxotere® had no effect on testosterone levels. They concluded that this study indicated that Taxotere® had an effect on early hormone-sensitive prostate cancer without affecting testosterone levels.
Comments: This is the first or one of the first studies to evaluate chemotherapy in early prostate cancer. It will be of interest to see if this concept evolves into studies of the impact of early chemotherapy on survival and quality of life compared to anti-androgen therapy.
Reference: Goodin S, Medina P, Capanna T, et al. Effect of docetaxel in patients with hormone-dependent prostate-specific antigen progression after local therapy for prostate cancer. Journal of Clinical Oncology. 2005;23: