Prospective Registry of ADC as First- and Second-line Treatment for Breast Cancer

Official title

ENCORE: Multicenter ProspectivE Registry of Sequential ANtibody Drug COnjugates (ADCs) in HER2 Negative Metastatic BREast Cancer (MBC)

Overview

Antibody-drug conjugates (ADCs) have demonstrated substantial improvement in progression free survival (PFS) and overall survival (OS) in phase III clinical trials in patients with metastatic triple negative breast cancer (mTNBC) and hormone receptor positive/HER2 negative (HR+/HER2-) metastatic breast cancer (MBC), offering an effective new treatment strategy. Several outstanding questions drive the decision to use ADC drugs clinically. This is a prospective, multi-site observational study of patients with metastatic breast cancer (mBC) who are being treated with FDA-approved antibody drug conjugates (ADCs) as part of routine care and aims to collect real-world data to evaluate the impact of ADC treatment as part of routine care.

Detailed description

PRIMARY OBJECTIVES:

I. Real-world progression free survival (rwPFS) of the first line of ADC under routine care (ADC1) by investigator assessment II. Real-world progression free survival (rwPFS) of the second line ADC under routine care (ADC2) by investigator assessment

SECONDARY OBJECTIVES:

I. To evaluate the efficacy of ADC1 and ADC2 as measured by duration of response (DOR), best overall response (BOR), disease control rate (DCR), and overall survival (OS) for each ADC.

II. To evaluate key safety parameters for ADC1 and ADC2 by chart review.

EXPLORATORY OBJECTIVES:

I. To evaluate/identify correlative biomarkers (e.g., circulating tumor DNA (ctDNA), circulating tumor cells (CTC), and tissue spatial correlates) of response/resistance to ADCs.

II. To evaluate patient reported outcomes (PROs) for each ADC.

OUTLINE:

Participants will have medical chart reviews and biospecimens collected for the duration of routine care with ADC1 and/or ADC2. After the last dose of ADC2, participants will continue to be followed for survival data collection via chart review every 12 weeks for up to 2 years.

Interventions

• Procedure Specimen collection
  Blood specimens will be collected during regular clinical visits for correlative and exploratory analysis
• Drug Non-Investigational Antibody-Drug Conjugates (ADC)
  ADC given under usual care for the treatment of cancer
• Other Medical Record Review
  Prospective and retrospective medical chart reviews will be conducted to obtain data for analysis.

Primary outcome measures

• Real-world progression free survival (rwPFS) of first line ADC (ADC1) [Time frame: Up to 5 years]
• rwPFS of second line ADC (ADC2) [Time frame: Up to 5 years]

Secondary outcome measures (6)

• Median Duration of Response (DOR) [Time frame: Up to 5 years]
• Best Overall Response (BOR) [Time frame: Up to 5 years]
• Overall Response Rate (ORR) [Time frame: Up to 5 years]
• Disease Control Rate (DCR) [Time frame: Up to 5 years]
• Median Real-World Overall Survival Rate (rwOS) [Time frame: Up to 5 years]
• Frequency of usual ADC-related Adverse Events (AEs) [Time frame: Up to 5 years]

Eligibility criteria

Inclusion criteria

• Male or female patients aged 18 years or greater with ability to provide written informed consent for this prospective registry study.
• Estimated life expectancy of at least at 3 months per investigator assessment.
• Willingness to provide an archival tissue sample and blood samples (20cc research blood collection at several timepoints) for research purposes.
• Cohort-specific enrollment criteria:

• Cohort 1: Histologically documented HR+/HER2- MBC with plan to start an FDA-approved ADC as their first ADC per standard of care (SOC).
• Cohort 2: Histologically documented metastatic TNBC with plan to start an FDA-approved ADC as their first ADC per standard of care
• Cohort 3: Histologically documented HR+/HER2- MBC with plan to start an FDA-approved ADC as their second ADC per standard of care (ADC1 should be an approved ADC administered per SOC or as monotherapy in a clinical trial; no prior experimental ADCs allowed). Clinical data from the first ADC must be available for retrospective review.
• Cohort 4: Histologically documented metastatic TNBC with plan to start an FDA-approved ADC as their second ADC per standard of care (ADC1 should be an approved ADC administered per standard of care or as monotherapy in a clinical trial; no prior experimental ADCs allowed). Clinical data from the first ADC must be available for retrospective review.
• Measurable disease is not required for any cohort.

Exclusion criteria

• Prior receipt of an experimental ADC in the metastatic setting. Of note, patients who received an FDA-approved ADC as their first ADC (as monotherapy, not in combination) can participate in cohorts 3 or 4 prior to starting their second FDA-approved ADC per standard of care. Of note, for all cohorts, experimental therapies are not allowed as intervening therapies after starting ADC1. If a patient enrolls on a clinical trial of an experimental therapy after ADC1, they will be taken off study.
• Current participation in a clinical trial with an ADC.
• Contraindication to research phlebotomy to collect \~20cc blood at each research blood draw timepoint.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Observational model

Case-control

Study locations

United States · 1 center

• University of California, San Francisco — San Francisco

Identifiers

NCT: NCT06774027 · 247516 · TBCRC 067

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗