Study on Prolonging Bone Metastasis-Free Survival in Men With Hormone Refractory Prostate Cancer

A Randomized, Double-Blind, Placebo-Controlled, Multi-Center Phase 3 Study of Denosumab on Prolonging Bone Metastasis-Free Survival in Men With Hormone Refractory Prostate Cancer

The purpose of this study is to compare the treatment effect of denosumab with placebo on prolonging bone metastasis-free survival in men with hormone refractory (androgen independent) prostate cancer who have no bone metastasis at baseline.

Participants were randomized to receive denosumab 120 mg or placebo every 4 weeks (Q4W) until approximately 660 participants developed bone metastasis or died and the primary efficacy and safety analyses were completed.

All participants undergoing scheduled assessments were offered open-label denosumab 120 mg subcutaneous (SC) until they either developed a bone metastasis, obtained access to commercially available product in this setting, or for up to 3 years, whichever came first. For participants who ended participation before the open-label extension (OLE) phase or withdrew from investigational product during the OLE phase, their survival data was to be collected every 6 months for up to 3 years after their last dose of investigational product.

Participants in the Czech Republic and United Kingdom were enrolled under a separate protocol for the OLE phase per Health Authority request, and are reported separately (Study 20080585; NCT01824342).

Inclusion Criteria:

• men with histologically confirmed prostate cancer
• bilateral orchiectomy at least 6 months before randomization or continuous androgen-deprivation therapy (ADT) with a gonadotropin releasing hormone (GnRH) agonist or antagonist for at least 6 months before randomization
• total testosterone level less than 50 ng/dL,
• hormone refractory (androgen independent) prostate cancer demonstrated during continuous ADT/post-orchiectomy defined as: 3 consecutive prostate-specific antigen (PSA) values with PSA1 < PSA2 < PSA3, each PSA value must be separated by at least 2 weeks, PSA2 and PSA3 greater than or equal to 1.0 ng/mL,
• high risk for development of bone metastasis defined as PSA value greater than or equal to 8.0 ng/mL, obtained no more than 3 months before randomization OR PSA doubling time less than or equal to 10.0 months

Exclusion Criteria:

• prior or current evidence of radiographically detectable bone metastasis
• known prior or current evidence of any metastatic involvement of distant organs (lymph node metastases in any region is acceptable)
• prior or current intravenous bisphosphonate administration