OT1-01-02: A Multicentre Study Assessing 12-Weekly Intravenous Bisphosphonate Therapy in Women with Low Risk Bone Metastases from Breast Cancer – The TRIUMPH Trial.

Abstract

Abstract Background: Metastatic bone disease is a major cause of morbidity and mortality for breast cancer patients. Bisphosphonates (BP) have been shown to significantly delay the onset and frequency of skeletal related events (SREs), improve pain control and overall quality of life. Most patients receive intravenous BP every 3–4 weeks regardless of their individual risk for a SRE. This “one size fits all” strategy could expose those patients at a relatively low risk of SREs to an increased chance of adverse drug effects, as well as to the financial and quality of life burden of multiple visits to the cancer centre for treatments. This study aimed to assess whether IV BP can be safely given at reduced frequency. Methods: The primary objective of this study is to demonstrate in women with biochemically defined low-risk bone metastases that the administration of IV BP every 12 weeks is sufficient to maintain biochemical stability for one year. Eligibility criteria include; bone metastases from breast cancer, have received at least three months of regular 3–4 weekly IV BP, satisfactory renal function, adequate dental health, no systemic treatment change or recent SRE within 4 weeks of study entry. Low risk disease will be defined as serum CTx levels <600 ng/L Biochemical failure is defined as CTx levels >600 ng/L measured at predefined time points (6, 12, 24, 36 and 48th). Secondary objectives are to evaluate the palliative benefit of 12-weekly IV BP therapy as reflected by occurrence of SREs, analgesic use, self-reported pain using the validated BP and FACT-BP questionnaires. Sample size was calculated at 68 patients. Given the small sample size, nonparametric Bootstrapping will be employed to calculate point estimates, standard deviations and 95% confidence intervals (CIs). An exploratory multivariable analysis will also be undertaken to determine baseline factors that were associated with patient's maintaining their telopeptide levels in the low risk range. Conclusion: TRIUMPH opened in October 2010 and as of June 2011, has quickly accrued 54/68 patients (79%). This trial has the potential to allow lower risk women to receive less frequent dosing of bisphosphonates, thus improving their quality of life with less cancer center visits and reducing their chance of drug induced adverse events. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr OT1-01-02.