Study of Trastuzumab Deruxtecan (T-DXd) vs Investigator's Choice Chemotherapy in HER2-low, Hormone Receptor Positive, Metastatic Breast Cancer

• Status: Recruiting
• Trial end date: 2025-04-18
• Target enrollment: 0
• Participant gender: All

Summary

This study will evaluate the efficacy, safety and tolerability of trastuzumab deruxtecan compared with investigator's choice chemotherapy in human epidermal growth factor receptor (HER)2-low, hormone receptor (HR) positive breast cancer patients whose disease has progressed on endocrine therapy in the metastatic setting.

• Phase: Phase 3
• Accepts Healthy Volunteers?: No

Details

• Lead Sponsor: AstraZeneca
• Collaborator: Daiichi Sankyo Company, Limited 3-5-1 Nihonbashihoncho, Chuo-ku, Tokyo
• Treatments: Albumin-Bound Paclitaxel; Capecitabine; Paclitaxel; Trastuzumab

Criteria

Key Inclusion Criteria:

• Patients must be ≥18 years of age

• Pathologically documented breast cancer that:

1. is advanced or metastatic

2. has a history of HER2-low or negative expression defined as IHC 2+/ISH- or IHC 1+ (ISH- or untested) or HER2 IHC 0 (ISH- or untested)

3. has HER2-low or HER2 IHC >0 <1+ expression

4. was never previously HER2-positive

5. is documented HR+ disease in the metastatic setting.

6. No prior chemotherapy for advanced or metastatic breast cancer.

7. Has adequate tumor samples for assessment of HER2 status

8. Must have either:

1. disease progression within 6 months of starting first line metastatic treatment with an endocrine therapy combined with a CDK4/6 inhibitor or

2. disease progression on at least 2 previous lines of endocrine therapy with or without a targeted therapy in the metastatic setting. Of note with regards to the ≥2 lines of previous ET requirement: disease recurrence while on the first 24 months of starting adjuvant ET, will be considered a line of therapy; these patients will only require 1 line of ET in the metastatic setting.

9. Has protocol-defined adequate organ and bone marrow function

Key Exclusion Criteria:

• Ineligible for all options in the investigator's choice chemotherapy arm

• Lung-specific intercurrent clinically significant illnesses

• Uncontrolled or significant cardiovascular disease or infection

• Active or prior documented interstitial lung disease (ILD)/pneumonitis or suspected ILD/pneumonitis that cannot be ruled out by imaging at screening

• Patients with spinal cord compression or clinically active central nervous system metastases

• Prior randomization or treatment in a previous trastuzumab deruxtecan study regardless of treatment arm assignment