Is High-Dose Leuprorelin Acetate Effective and Safe in Asian Men with Prostate Cancer? An Open-Label, Non-Comparative, Multi-Center Clinical Trial

PURPOSE: Leuprorelin is a well known luteinizing hormone releasing hormone agonist. However, there are insufficient data on the efficacy and safety of high dose leuprorelin acetate, especially in Asian patients with prostate cancer. We aimed to investigate the safety and efficacy of leuprorelin acetate 22.5 mg administered at three-month intervals in patients with prostate cancer. MATERIALS AND METHODS: In an open, prospective clinical trial enrolling 47 patients, we aimed to assess the efficacy and safety of leuprorelin acetate 22.5 mg in treating patients with histologically confirmed prostate cancer. The primary objective of this study was to evaluate the efficacy of the leuprorelin acetate 22.5 mg in producing and maintaining castration levels of testosterone over a 6-month follow-up period and to determine its safety profile. RESULTS: All 42 patients achieved serum testosterone levels within the castration range by 4 weeks. A breakthrough response was observed in one of 36 patients by 8 weeks. However, this patient was medically castrated by 12 weeks. There were no significant prostate-specific antigen (PSA) or testosterone changes according to clinical stage or body mass index. Twenty adverse events (AEs) in 15 of 42 patients (35.7%) were observed during this study. The most common AEs were hot flushes (n=4, 20.0%) with mild intensity, pain (n=2, 10.0%), and infection (n=2, 10.0%). No patient withdrew from the study due to AEs. CONCLUSION: Leuprorelin acetate 22.5 mg was shown to be effective and safe in Asian patients with prostate cancer, even though sexual function decreased.