BURST CME™ Activity 1: Foundations of Endocrine Resistance and Oral SERDs in HR+/HER2– Metastatic Breast Cancer

Activity Overview

The emergence of endocrine resistance is a critical challenge in the management of hormone receptor–positive/HER2-negative (HR+/HR–) metastatic breast cancer (MBC). Activating mutations in the ESR1 gene, which encodes the estrogen receptor, are key biomarkers of acquired resistance; they occur in a substantial proportion of patients who experience progression on endocrine therapy. Next-generation oral selective estrogen receptor degraders (SERDs) have been developed to overcome ESR1-driven resistance, with multiple agents now FDA approved in this setting. Accurate and timely biomarker testing is essential to identify patients who may benefit from oral SERD–based treatment strategies. In this activity, 2 experts discuss the biologic mechanisms underlying endocrine resistance, review the rationale and clinical and real-world evidence for oral SERDs, and outline best practices for ESR1 detection. Faculty highlight the growing role of liquid biopsy–based next-generation sequencing for ESR1 detection at progression, review current guideline recommendations, and discuss practical barriers and solutions for implementing these assays in routine care.

Target Audience

This educational program is primarily directed toward a global audience of medical oncologists, advanced practice providers, nurses, and other health care professionals who are involved in the management of patients with advanced or metastatic breast cancer.

Learning Objectives

Upon successful completion of this activity, you should be better prepared to:

• Implement guideline-concordant molecular testing strategies across the disease continuum for patients with HR+/HER2– MBC

The staff of Physicians’ Education Resource^®, LLC have no relevant financial relationships with ineligible companies.

PER^® mitigated all conflicts of interest for faculty, staff, and planners prior to the start of this activity by using a multistep process.

Off-Label Disclosure and Additional Disclaimers

This activity may or may not discuss investigational, unapproved, or off-label use of drugs. Learners are advised to consult prescribing information for any products discussed. The information provided in this accredited activity is for continuing education purposes only and is not meant to substitute for the independent clinical judgment of a health care professional relative to diagnostic, treatment, or management options for a specific patient’s medical condition. The opinions expressed in the content are solely those of the individual faculty members and do not reflect those of PER^® or any company that provided commercial support for this activity.

This accredited activity has been developed in accordance with applicable accreditation standards to ensure balance, independence, objectivity, and scientific rigor. Faculty were instructed to use generic names where possible and to base recommendations on the best available evidence.

In the context of clinical discussion, proprietary product names may be mentioned. Such references are made for educational purposes only and do not constitute endorsement of any commercial product or service.

Learners are encouraged to independently evaluate the information presented and apply their own clinical judgment when considering patient care decisions.

This activity may have used AI-assisted tools to support educational development. All content was reviewed and approved by qualified faculty or planners. The accredited provider retains full responsibility for accuracy, balance, and independence.