Key clinical point: Bisphosphonate therapy for 5 vs 2 years in patients with high-risk early breast cancer yields no added survival benefit and leads to increased risk for adverse events.
Major finding: There were no significant differences in disease-free survival (hazard ratio [HR], 0.97; P = .81), overall survival (HR, 0.98; P = .90), and distant disease-free survival (HR, 0.87; P = .38) between 5- and 2-year bisphosphonate treatment groups. The rate of adverse events was 46.2% with 5-year therapy and 27.2% with 2-year treatment.
Study details : A randomized phase 3, open-label SUCCESS A trial of 2,987 patients with high-risk early breast cancer randomly assigned to receive bisphosphonate zoledronate for either 5 or 2 years.
Disclosures: The study was supported by AstraZeneca, Chugai, Menarini Silicon Biosystems (formerly Veridex), Lilly, Novartis, and Sanofi-Aventis. The authors received honoraria, personal fees, research support, consulting fees, and travel grants from various sources.
Source: Friedl TWP et al. JAMA Oncol. 2021 Jun 24. doi: 10.1001/jamaoncol.2021.1854 .