Zoledronate in Preventing Bone Loss in Postmenopausal Women Who Are Receiving Letrozole for Stage I, Stage II, or Stage IIIA Breast Cancer

Breast Cancer Clinical Trial

Official title: A Randomized, Controlled, Open-Label Trial of Empiric Prophylactic vs. Delayed Use of Zoledronic Acid for Prevention of Bone Loss in Postmenopausal Women With Breast Cancer Initiating Therapy With Letrozole After Tamoxifen

Status Completed

Clinical Trial Summary

RATIONALE: Estrogen can cause the growth of breast cancer cells. Hormone therapy using letrozole may fight breast cancer by lowering the amount of estrogen the body makes. Zoledronate may prevent bone loss in patients who are receiving letrozole. It is not yet known which schedule of zoledronate is more effective in preventing bone loss in patients with breast cancer.

PURPOSE: This randomized phase III trial is studying two different schedules of zoledronate to compare how well they work in preventing bone loss in postmenopausal women who are receiving letrozole for stage I, stage II, or stage IIIA breast cancer.

Clinical Trial Description

OBJECTIVES:

• Compare the effectiveness of zoledronate vs standard care in reducing bone loss during the first 12 months of study treatment in postmenopausal women with stage I-IIIA breast cancer initiating letrozole after prior treatment with tamoxifen.

• Compare the effect of immediate vs delayed zoledronate, annually at 2-5 years post-baseline, in reducing bone loss in these patients.

OUTLINE: This is a randomized, open-label, multicenter study. Patients are stratified according to duration of prior tamoxifen therapy (≤ 2 years vs > 2 years); time since tamoxifen therapy was discontinued (< 1 vs ≥ 1 year); prior adjuvant chemotherapy (yes vs no); and baseline total lumbar spine or femoral neck bone mineral density (BMD) T-score (> -1 standard deviation [SD] vs between -1 to -2 SD). Patients are randomized to 1 of 2 treatment arms.

• Arm I (immediate therapy): Patients receive oral letrozole once daily. Patients also receive zoledronate IV over 15 minutes once every 6 months.

• Arm II (delayed therapy): Patients receive oral letrozole as in arm I. Patients with radiologic evidence of bone loss after 1 year of letrozole therapy receive zoledronate as in arm I.

In both arms, treatment continues for up to 5 years in the absence of disease progression or unacceptable toxicity.

PROJECTED ACCRUAL: A total of 550 patients (275 per treatment arm) will be accrued for this study within 28 months. ;

Study Design

Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Supportive Care

Related Conditions & MeSH terms

• Breast Cancer
• Breast Neoplasms
• Osteoporosis

• NCT number: NCT00107263
• Study type: Interventional
• Source: Alliance for Clinical Trials in Oncology
• Status: Completed
• Phase: Phase 3
• Start date: January 2005
• Completion date: August 2012