Effect of denosumab versus zoledronic acid on health-related quality of life in patients with metastatic breast cancer.

Abstract

272 Background: Patients with breast cancer and bone metastases often experience skeletal-related events (SREs) and pain, which can impact health-related quality of life (HRQoL). Denosumab is superior to zoledronic acid (ZA) in preventing SREs and more effective in delaying moderate or severe pain in patients with advanced breast cancer. We now describe the effect of denosumab or ZA treatment on HRQoL in these patients. Methods: Patients enrolled in this double-blind, double-dummy study were randomized to receive denosumab (120 mg SC) or ZA (4 mg IV) every 4 weeks. Patients completed the Functional Assessment of Cancer Therapy-General (FACT-G) questionnaire at baseline (BL), day 8, and each monthly visit to assess overall HRQoL. Higher scores (range 0 to 108) reflect a better HRQoL. Changes in HRQoL were summarized through month 18, when 30% of patients had died or dropped out due to disease progression or withdrawal of consent. Increases or decreases of ≥ 5 points in the FACT-G total score were considered clinically meaningful. Pain was evaluated by the Brief Pain Inventory–Short Form (BPI-SF). HRQoL was assessed in subgroups with no/mild pain or moderate/severe pain at BL. Results: The BL mean (SD) FACT-G score was similar for denosumab (n = 956) 72.7 (16.4) and ZA (n = 952) 73.6 (16.5) groups and increased from BL to month18 for both groups reflecting improved HRQoL. An average of 3.2% more (range 0.9% to 6.8%) denosumab-treated patients than ZA-treated patients experienced a ≥ 5-point increase in HRQoL from months 1 to 18. Fewer denosumab than ZA-treated patients reported a ≥ 5-point decrease in HRQoL (average 2.7% fewer; range 0.6% to 5.8%). Among patients with no/mild pain at BL, an average of 4.1% more (range -0.6% to 9.3%) denosumab-treated patients had a ≥ 5-point increase in FACT-G score from month 4 to 18. In this same subgroup, fewer denosumab-treated patients had a ≥ 5-point decrease in HRQoL over 18 months (average 2.4% fewer; range -4.4% to 6.3%). Similar patterns in FACT-G scores were noted for the subgroup with moderate/severe pain at BL. Conclusions: In patients with advanced breast cancer, a greater proportion treated with denosumab than ZA had a meaningful improvement in HRQoL regardless of BL pain level.