Zoledronic Acid Benefited Those With Bone Mets Regardless of HSPC/CRPC Status

Zoledronic acid (ZA) did not improve survival outcomes in patients with different prostate cancer statuses outside of metastatic castration-resistant disease, including those with hormone-sensitive disease, according to the results of a recent meta-analysis published in PLoS One.

“ZA is the most potent bisphosphonates and is currently recommended for the management of bone metastasis in various solid tumors. It functions as an adjunctive treatment and bone-targeted therapy for supportive care with metastatic castration-resistant prostate cancer,” study researchers explained.

However, not as much is known about the effect of ZA in other types of prostate cancer such as hormone-sensitive prostate cancer (HSPC), metastatic HSPC, and non-metastatic castration resistant prostate cancer (nmCRPC).

The researchers reviewed 15 eligible randomized controlled trials that included a ZA intervention. In all, the study included 8,280 men (424 were Asian).

There was no significant improvement in overall survival in the HSPC (pooled hazard ratio (HR)=0.96) or CRPC subgroups (HR=0.78), and no improvement in men with (HR=0.85) or without bone metastasis (HR=0.95; M1 and M0).

Interestingly, although non-Asian men had no improvement in overall survival, men that identified as Asian did have improved overall survival (HR=0.67; 95% CI, 0.48=0.95; P=.02).

“However, for the overall survival outcome, the data included a wide range of patients, and heterogeneity must be considered, especially considering the effect of cardiovascular death caused by androgen deprivation therapy,” the researchers wrote. “Therefore, this conclusion should be conservatively interpreted.” Further research is needed to explore the relationship between race and prostate cancer, they wrote.

Skeletal-related events (SREs) were significantly decreased in Asian men (odds ratio [OR]=0.42; 95% CI, 0.24-0.71; P=.001) and in men with M1 status (OR=0.65; 95% CI, 0.45-0.95; P=.02). This finding confirms the effect of ZA seen in patients with metastatic CRPC.

“However, there was no remarkable decrease in the HSPC and CRPC subgroups,” the researchers wrote. “These results imply that regardless of the HSPC or CRPC status, patients with bone metastasis can benefit from ZA, but no benefit is gained in patients without bone metastasis.”

Among men with HSPC there was a stable improvement in increased bone mineral density percentage with an mean difference of 6.65 (P=.001).

Reference

Do Disease Status and Race Affect the Efficacy of Zoledronic Acid in Patients With Prostate Cancer? A Systematic Review and Meta-Analysis of Randomized Control Trials