Clinical trial · Interventional
Aromatase Inhibitor Host Factors Study
Patient-related Predictors of Estrogen Suppression in Postmenopausal Women Using Adjuvant Letrozole
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Summary
Brief summary (as posted)
The purpose of this study is to examine how key patient factors, including body size affect how well letrozole suppresses circulating estrogen levels. This study has two components: (1) Part A - an observational phase to evaluate the impact of vitamin D and obesity on estrogen suppression in post-menopausal women already receiving letrozole treatment, and (2) Part B - an interventional phase for women with body mass index (BMI) \> 25 kg/m2 to assess the effect of double AI dose on estrogen levels. If BMI or other patient factors reduce the effectiveness of letrozole, modifications to treatment recommendations and studies to test higher dosing of letrozole may be needed to maximize the benefit of this treatment and minimize the risk of the breast cancer coming back.
Conditions
Conditions (1)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Breast Neoplasms | Breast Neoplasm | ONTOLOGY_EXACT | 0.98 |
Interventions
Interventions (1)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| Letrozole | Drug | Letrozole | ALIAS |
Design
Arms and outcomes
Arms (1)
- type
- OTHER
- label
- Post-menopausal Women Using Adjuvant Letrozole
- description
- Part A Routine Care Letrozole; Part B Double Dose Letrozole in overweight/obese participants
- interventionNames
- Drug: Letrozole
Primary outcomes (5)
- measure
- Part A Correlation of Day 29 Estradiol With BMI
- timeFrame
- Day 29
- description
- Determine if estradiol levels vary with BMI levels after 28 days of monitored adherence to standard dose letrozole, by calculating the Pearson correlation between estradiol and log-transformed BMI
- measure
- Part A Correlation of Day 29 Estrone With BMI
- timeFrame
- Day 29
- description
Eligibility
Eligibility (as posted)
- Sex
- Female
Show eligibility criteria text
Inclusion Criteria: * Postmenopausal female patients * histological confirmed diagnosis of estrogen receptor and/or progesterone receptor positive breast cancer (Stage I-III) who have completed local therapy * Currently prescribed and taking letrozole 2.5 mg daily for a minimum of 3 months * Willing to provide written informed consent to participate * for the experimental arm: all of the above and body mass index (BMI) \> 25 kg/m2 Exclusion Criteria: * Known abnormal liver or renal function defined by: 1. Serum Creatinine \> 1.25 times institutional upper limit of normal (ULN) or Calculated Creatinine Clearance \< 40 mL/min 2. Serum Bilirubin, Aspartate transaminase (AST) or alanine transaminase (ALT) \> 1.5 times ULN * Presence of persistent local or known metastatic cancer
References
Publications (0)
Data not yet available