The Multi-center Clinical Trial of Leuprolide Acetate Depot(LphereⓡDepot inj 3.75mg) for Evaluation of Efficacy and Safety in Patients with Prostate Cancer

Abstract

Purpose: We evaluated the efficacy and safety of monthly administrations of the luteinizing hormone-releasing hormone agonists leuprolide acetate depot (Luphereⓡ Depot inj 3.75mg) in patients with prostate cancer.

Materials and Methods: Between December 2005 and April 2006, 96 men with prostate cancer treated with leuprolide acetate 3.75mg. The agent was injected subcutaneously every four weeks for three injections. Primary endpoint was the percentage of men whose serum testosterone concentrations declined to and were maintained at or below castrate level (50ng/dl) during 12 weeks of treatment. Secondary endpoints were serum testosterone levels, the changes of prostate specific antigen (PSA) levels, the percentage of men whose prostate specific antigen levels were reached nadir after 12 weeks. Patients were monitored for clinical adverse events and laboratory abnormalities.

Results: The testosterone concentrations were maintained below castration levels in 89.02% of patients at 4-12 weeks. At baseline, the mean testosterone concentration was 427.32±172.35ng/dl. And the mean testosterone concentration decreased significantly 35.54±95.09ng/dl at 4 weeks, 15.94±44.65ng/dl at 8 weeks and 12.42±21.00 ng/dl at 12 weeks from baseline (p＜0.001). At baseline, the mean PSA level was 76.88±335.71ng/ml. PSA level decreased to 15.79±50.99ng/ml at 4 weeks, 5.68±17.65ng/ml at 8 weeks and 3.59±10.72ng/ml at 12 weeks from baseline (p＜0.001). The adverse events were flushing, increased sweating, and elevated liver enzymes. They are well-known adverse events of leuprolide acetate.

Conclusions: Leuprolide acetate 3.75mg reduced testosterone concentrations and maintained castration effectively. Leuprolide acetate 3.75mg was well tolerated with the majority of systemic adverse events being physiologic results of the suppression of testosterone. Therefore, the present findings suggest that leuprolide acetate 3.75mg is useful for treating men with prostate cancer.