A Clinical Trial to Assess the Safety of 0.005 % Estriol Vaginal Gel in Hormone Receptor-Positive Postmenopausal Women With Early Stage Breast Cancer in Treatment With Aromatase Inhibitor in the Adjuvant Setting

1. Written informed consent prior to beginning specific protocol procedures.

2. Patients must have histological confirmation of breast adenocarcinoma with stage I-IIIA, documented at a local pathology department.

3. The breast tumors must be estrogen-receptor positive and/or progesterone receptor positive (≥1% of stained tumor cells by Immunohistochemistry (IHC) as determined by the local laboratory) with any Human Epidermal Growth Factor Receptor 2(HER2) status.

4. Postmenopausal status defined as: 12 months of spontaneous amenorrhea or 6 months of spontaneous amenorrhea with serum FSH levels \> 40 Milli-international units per milliliter (mIU/ml) or 6 weeks postsurgical bilateral oophorectomy with or without hysterectomy.

5. Patient must be receiving the non-steroidal aromatase inhibitors anastrozole or letrozole as breast cancer treatment in the adjuvant setting for a minimum of 6 months.

6. Women suffering from moderate to severe vaginal dryness according to the FDA guidelines for drug development in postmenopausal women (Center for Drug Evaluation and Research, (CDER) Jan 2003). A moderate symptom will be considered if the symptom is present, bothersome and annoying, and a severe symptom will be considered if the symptom is present, bothersome and annoying, and interferes with the normal patient activity.

7. Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 or 1.

8. Adequate bone marrow as defined by the following laboratory values:

1. Absolute Neutrophil Count (ANC) ≥ 1.5 x 109/L.

2. Platelets (plt) ≥ 100 x 109/L.

3. Hemoglobin (Hgb) ≥ 10 g/dl.

9. Patient has adequate organ function as defined by the following laboratory values:

1. Serum creatinine ≤ 1.5 x Upper Limit of Normal (ULN).

2. Bilirubin ≤ 1.5 × ULN.

3. Alkaline phosphatase ≤ 2 × ULN.

4. Aspartate Aminotransferase (AST) and Alanine Aminotransferase (ALT) ≤ 2 × ULN.

10. Willingness and ability to comply with scheduled visits, treatment plan, laboratory tests and other study procedures.

What this study is about