Do Aromatase Inhibitors (AIs) Decrease Intestinal Calcium Absorption?

Breast Cancer Clinical Trial

Official title:

Do Aromatase Inhibitors (AIs) Decrease Intestinal Calcium Absorption?

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00766532
• Other study ID #: H-2008-0144
• Status: Completed
• Phase: Phase 4
• First received: October 2, 2008
• Last updated: September 13, 2012
• Start date: January 2009
• Est. completion date: October 2010

Study information

• Verified date: September 2012
• Source: University of Wisconsin, Madison
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Interventional

Clinical Trial Summary

Research Question: Do Aromatase Inhibitors Decrease Intestinal Calcium Absorption?

Study Design: Postmenopausal women with early stage breast cancer initiating aromatase inhibitor adjuvant therapy will participate in this two-month study. The primary study outcome is the change in intestinal calcium absorption following such therapy. Secondary outcomes are the changes in bone resorption markers and musculoskeletal signs and symptoms after initiation of therapy.

We will interview women and review their medical records to determine eligibility. Eligible subjects will undergo two calcium absorption studies. The first study will determine their baseline calcium absorption, and the second study will occur after taking an aromatase inhibitor daily for at least 6 weeks. Women will present to the research unit in the early morning and receive an oral and intravenous stable calcium tracer with breakfast. Over the next 24 hours, we will collect all urine for measurement of its calcium content. During each inpatient stay, we will assess musculoskeletal symptoms by questionnaire and joint examination. Each woman will complete a four-day diet diary twice during the study.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 12
• Est. completion date: October 2010
• Est. primary completion date: October 2010
• Accepts healthy volunteers: No
• Gender: Female
• Age group: N/A and older

Eligibility

Inclusion Criteria:

• Women at least 5 years past menopause, defined as date of last menses or bilateral oophorectomy

• Newly diagnosed breast cancer and starting an AI as initial adjuvant therapy

Exclusion Criteria

• Recent, current or planned chemotherapy for breast cancer, as this may have independent effects on intestinal health, calcium homeostasis and bone turnover

• Allergy or intolerance to orange juice, as one isotope is given with orange juice

• Current use of over-the-counter or prescription antacids, as they may influence Ca-Ab

• Intestinal conditions associated with malabsorption or low gastric acid levels including Crohn's disease, ulcerative colitis, pernicious anemia, bacterial overgrowth, celiac sprue, chronic diarrhea or use of antibiotics within the past month

• Known Stage 4 or 5 Chronic Kidney Disease, defined as an estimated GFR <30 cc/minute

• Use of medications known to interfere with calcium or vitamin D metabolism, including oral steroids or anticonvulsants

• Significant lymphedema precluding adequate intravenous access

Study Design

Endpoint Classification: Safety Study, Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Diagnostic

Related Conditions & MeSH terms

• Breast Cancer
• Fracture
• Osteopenia
• Osteoporosis

Intervention

Drug:
• Aromatase Inhibitor
Any aromatase inhibitor started as initial adjuvant therapy

Locations

Country	Name	City	State
n/a

Sponsors (1)

Lead Sponsor	Collaborator
University of Wisconsin, Madison

References & Publications (1)

Tevaarwerk A, Burkard ME, Wisinski KB, Shafer MM, Davis LA, Gogineni J, Crone E, Hansen KE. Aromatase inhibitors and calcium absorption in early stage breast cancer. Breast Cancer Res Treat. 2012 Jul;134(1):245-51. doi: 10.1007/s10549-012-1982-z. Epub 201 — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in Intestinal Calcium Absorption Related to Aromatase Inhibitor Therapy	intestinal calcium absorption	baseline and 6 weeks later	Yes