Evaluating Use of Bone-Modifying Agents to Treat Skeletal-Related Events in Cancer

Skeletal-related events are frequent complications in patients with cancers. Two abstracts presented at the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting analyzed the use of bone-modifying agents (BMAs) in patients with newly diagnosed multiple myeloma (MM) and breast cancer.

In the first abstract, the researchers implemented a program to improve the time to initiation of BMAs in patients with newly diagnosed MM.¹ While guidelines from ASCO and the International Myeloma Working Group recommend that patients on active therapy to treat MM receive concurrent care with a BMA to decrease the risk of skeletal-related events, research has found that only about half of patients receive a BMA within 90 days of their first chemotherapy treatment.

The authors evaluated 161 patients with newly diagnosed MM and found that the average time difference between starting treatment for MM and starting treatment with a BMA was 10.5 weeks. They also compared time to initiation of BMA between Cleveland Clinic affiliated sites and the Cleveland Clinic Main Campus (MC). They found that time to initiation was 10.6 weeks at MC versus 9.1 weeks at affiliated sites.

Using physician education and awareness of this internal baseline data, the time to initiation of BMA improved from 10.5 weeks to 4.3 weeks. One of the barriers they identified that needed to be addressed was effective communication with patients on the benefits of BMAs.

“We plan to incorporate BMA guidelines in our institutional care path with the goal to decrease time to initiation at all affiliated practices,” the authors wrote.

In the second abstract, researchers evaluated zoledronic acid (ZA) and denosumab (Den) to compare efficacy of these treatments in patients with breast cancer.² Both treatments reduce skeletal-related events, but “ASCO guidelines do not recommend one over another, and survival and real-world outcome data to guide point-of-care decision-making is lacking,” they wrote.

Patients treated for breast cancer at Stanford HealthCare between 2009 and 2018, who were receiving standard of care and BMA therapy, were included in the study if they had at least 2 electronic health records documenting BMA administration. The patients were grouped into Den only, ZA only, or both. A total of 802 patients were included in the study.

Using propensity score matching, 25% of patients on ZA only had skeletal-related events compared with 13% (P = .00027) of patients on Den only. The ZA-only group had 81 deaths compared with 41 deaths in the Den group (37% vs 19%; P = .00346).

“This preliminary retrospective analysis of unsupervised BMA use suggests that Den is superior to ZA for the outcomes of interest; confirmatory analyses are underway,” the authors concluded.

References

1. Rosko N, Lee S, Samaras CJ, et a. Improving time to initiation of bone modifying agents in patients with newly diagnosed multiple myeloma. Presented at: 2019 American Society of Clinical Oncology Annual Meeting; May 31-June 4, 2019; Chicago, IL. Abstract: 6528.

2. Karimi Y, Gombar S, Dean L, et al. Real-world efficacy of bone modifying agents (BMAs) in patients with breast cancer (BC) treated in an academic health system: use of the “green button.” Presented at: 2019 American Society of Clinical Oncology Annual Meeting; May 31-June 4, 2019; Chicago, IL. Abstract: e18054.