Efficacy and tolerability of 1-and 3-month leuprorelin acetate depot formulations (Eligard®/Depo-Eligard®) for advanced prostate cancer in daily practice: a Belgian prospective non-interventional study

Introduction: The 1-, 3- and 6- month biodegradable polymer matrix depot formulations of leuprorelin acetate (Eligard (R)/Depo-Eligard (R), Astellas Pharma Inc/BV) were shown to reduce testosterone and prostate-specific antigen levels and to be well tolerated in patients with advanced prostate cancer in several clinical trials. This study aimed at evaluating the efficacy, safety and tolerability of the 1- and 3-month leuprorelin acetate depot formulations in daily clinical practice. Material and methods: A prospective, open-label, non-interventional, phase IV study (MANTA) was conducted in 243 Belgian prostate cancer patients who had been prescribed the 1-month (7.5 mg) or 3-month (22.5 mg) leuprorelin acetate depot formulation. Patients were followed for at least 3 months. Results: Median serum prostate-specific antigen levels were reduced by 95% from 12.0 ng/ml at baseline to 0.60 ng/ml after a median follow-up time of 132 days, while median testosterone levels were reduced by 94% from 360 ng/dl to 20 ng/dl. Partial or complete treatment response was observed in 83% of patients at the final visit (according to the physician's assessment). Ninety-two patients (37.86%) experienced treatment-emergent adverse events, with injection site-related reactions, hot flushes and tumor flare being the most common ones. Overall safety and tolerability of the leuprorelin acetate depot formulation were rated as good or excellent by 90% of physicians. Conclusions: These data are consistent with efficacy and tolerability results from clinical trials. They confirm that the 1- and 3-month leuprorelin acetate depot formulations are well tolerated and reliably lower serum prostate-specific antigen and testosterone levels in routine clinical practice.