Compliance with every 12-week zoledronic acid dosing guidelines for bone metastasis in breast cancer patients.

Abstract

81 Background: Bisphosphonates, including zoledronic acid (Zometa), decrease skeletal-related events in breast cancer patients with bone metastasis but are also associated with side effects and utilization costs. Data from a randomized trial supporting 12-week versus 4-week dosing of Zometa was released in July 2016 and officially published in January 2017. We examined the practice pattern of Zometa dosing over time in our practice to determine compliance and develop interventions for improvement. Methods: We conducted a retrospective chart review on all breast cancer patients treated at Parkland Health and Hospital System oncology clinic to identify patients who were initiated on Zometa for bone metastasis between June 2015 and September 2019. The initially prescribed dosing frequencies were assessed for time periods before and after the Zometa dosing data was made available. The prescribing patterns were also compared between teaching and non-teaching clinics. An educational review of the guidelines was presented to providers in all clinics in March 2020 to improve compliance. Results: In the year prior to July 2016, of the 27 patients who started Zometa, only 1 (4%) was on every 12-week dosing. In the six months after release of the data, 29% (6/21 patients) were placed on 12-week Zometa dosing. Between January 2019 and September 2019, 52% of patients were started on the recommended 12-week dosing interval. These patterns were consistent between teaching and non-teaching clinics. Conclusions: We found that the variability in Zometa prescribing patterns persisted despite updated national guidelines and multiple studies supporting 12-week dosing intervals. In addition to educational interventions, we plan to implement electronic interventions to improve rates of compliance with the goal of 80% adherence by September 2020. Improved adherence will likely lead to a reduction in potential complications from treatment as well as infusion costs (estimated $482.81 saved per patient annually).