Efficacy and risk of osteonecrosis of the jaw for pamidronate, zoledronic acid, and denosumab in comparison to alendronate in multiple myeloma patients.

BACKGROUND: Approximately 70% of multiple myeloma patients develop pathologic fractures. Osteoclast inhibitors can provide reduction in vertebral fractures with an increased risk of osteonecrosis of the jaw (ONJ). ONJ associated with currently used osteoclast inhibitors causes significant morbidity, often from delayed diagnosis and ineffective treatment.

METHODS: The TriNetX Diamond Network was used to create patient cohorts for each medication: alendronate, pamidronate, zoledronic acid, and denosumab. All patients had a diagnosis of multiple myeloma as identified by International Classification of Disease-10 (ICD-10) code C90.0. Pamidronate, zoledronic acid, and denosumab were each compared to alendronate for 5-year incidence of pathologic vertebral fracture (ICD-10 M48.50XA) and development of ONJ.

RESULTS: The 5-year risk of pathologic vertebral fracture was not statistically different between alendronate versus pamidronate, zoledronic acid, and denosumab. However, the 5-year risk of ONJ was significantly higher for both zoledronic acid and denosumab (relative risk 4.85 and 2.9, respectively).

CONCLUSION: This study shows that fracture reduction risk is comparable for all four treatments in multiple myeloma patients, but ONJ risk is lowest for alendronate and pamidronate. Overall, these data support the continued use of pamidronate and alendronate in multiple myeloma patients.