OBJECTIVES: Two innovative pharmaceutical forms of leuprorelin acetate have been developed as 1-month and 3-month implants for the treatment of advanced hormone-dependent prostate cancer.
These products contain active substance dispersed homogeneously in a biodegradable polymer. Here we present the key results from the clinical development of these slow-release implant formulations of leuprorelin.
METHODS: Two therapeutic studies of the 1-month implant were performed: a randomized, controlled study comparing the leuprorelin implant with leuprorelin prolonged-release microspheres (Enantone) as the active control; and a single-arm study of the leuprorelin implant. For the 3-month implant, four therapeutic studies were performed: a randomized, controlled study comparing the leuprorelin implant with leuprorelin prolonged-release microspheres (Trenantone) as the active control; a single-arm study of the leuprorelin implant; and two long-term studies with the 3-month implant administered twice, either 12 or 16 weeks apart. A pooled analysis of data from the comparator-controlled and single-arm studies of the 3-month implant was also conducted. The main inclusion criterion for all studies was histologically confirmed advanced prostate cancer, with primary endpoints based around successful testosterone suppression (≤ 0.5 ng/ml).
RESULTS: In the comparator-controlled studies, both implants were as effective as the microspheres for achieving successful testosterone suppression and normalization of prostate-specific antigen (PSA) levels. Data from the single-arm and long-term studies were consistent with those from the comparator-controlled studies. In the pooled analysis, significantly more patients treated with the 3-month implant achieved successful testosterone suppression compared with the comparator (p ≤ 0.01). The safety profile of the implants in the comparator-controlled studies was similar to that of the prolonged-release microsphere formulation, and consistent with that of the luteinizing hormone-releasing hormone agonist class.
CONCLUSIONS: The innovative 1-month and 3-month implants of leuprorelin acetate are at least as effective as leuprorelin acetate prolonged-release microspheres for achieving successful testosterone suppression and normalization of PSA in men with advanced hormone-dependent prostate cancer, with a comparable safety profile.
Written by:
Geiges G, Schapperer E, Thyroff-Friesinger U, Engert ZV, Gravel P. Are you the author?
Vorstandsvorsitzender IQUO e.V., Berlin, Germany.
Reference: Ther Adv Urol. 2013 Feb;5(1):3-10.
doi: 10.1177/1756287212471096
PubMed Abstract
PMID: 23372606
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