A metanalysis on cabozantinib and bone metastases: true story or commercial gimmick?

Abstract

Is it true that cabozantinib should be the preferred option treating patients with bone metastases? Are there any reliable comparisons between this drug and other standard options in this subgroup? To address the issue, we performed a systematic review and metanalysis of randomized trials with cabozantinib, to assess its effectiveness, in terms of overall survival, according to the presence of bone metastases. We included (a) randomized controlled trials; (b) any solid tumors and therapeutic line; and (c) overall survival data available according to the site of disease. Cabozantinib improved overall survival both for the group with bone metastases, with risk of death decreased by 53% (hazard ratio, 0.47; 95% confidence interval, 0.26-0.87; P=0.02) and for the group without bone metastases, decreasing the risk of death by 44% (hazard ratio, 0.56; 95% confidence interval, 0.40-0.79; P=0.001) over the standard of care. The difference was not significantly different between the two groups. Despite cabozantinib can be undoubtedly listed as a good therapeutic option for cancer patients with bone metastases, it seems that its preclinical profile against bone remodeling does not translate into an actual clinical relevance, preventing from considering the presence of bone metastases as principal criterion for the choice of this drug.