A new analysis of 26 clinical trials looked at whether bone-strengthening drugs help men with non-metastatic prostate cancer who are on androgen deprivation therapy (ADT), a common hormone treatment that can weaken bones. The drugs studied were bisphosphonates (given intravenously or orally) and denosumab. The analysis focused on bone health outcomes like fractures, bone mineral density (BMD), and bone turnover markers.
The clearest finding was for denosumab: men who received it had a large reduction in new spine fractures at 12, 24, and 36 months compared to those who did not. For example, at 36 months the risk was about 62% lower. Both bisphosphonates and denosumab increased BMD at the hip and spine and reduced bone turnover markers, which are signs of bone activity.
However, the picture for fractures was less certain. Oral bisphosphonates did not show a clear effect on fractures at 12 months, and intravenous bisphosphonates did not reduce spine fractures at 36 months. The authors note that the evidence for these drugs is of very low certainty, meaning more research is needed.
Safety information was limited. Gastrointestinal issues were the most common side effect across all drugs. Acute phase reactions were common with intravenous bisphosphonates, and jaw osteonecrosis was rare. The analysis did not report serious adverse events or how many people stopped treatment.
The main limitation is that data on mortality were scarce. Also, the trials may not have been designed to detect fracture differences. The authors say well-designed, larger trials are needed to confirm effects on fracture risk. For now, men on ADT should discuss bone health with their doctor.
