Therapeutic Targeting of HER3 in Breast and Lung Cancer: Preparing for the Future

Therapeutic Targeting of HER3 in Breast and Lung Cancer: Preparing for the Future

Med-IQ Select
Online Course | Specialties: Oncology
Released: 12/30/2020
Expires: 12/29/2021
Max Credits: 0.5
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Helena A. Yu, MD
Thoracic Oncology Service
Memorial Sloan Kettering Cancer Center
Weill Cornell Medical College
New York, NY

Activity Planners
Jaime Symowicz, PhD
Manager, Educational Strategy and Content
Baltimore, MD

Jane Frutchey, MS
Managing Editor
Baltimore, MD

Samantha Gordon, MS
Accreditation Manager
Baltimore, MD

Amy Sison
Director of CME
Baltimore, MD

Jessica Martin, PhD
Saint Paul, MN

Learning Objectives
Upon completion, participants should be able to:

  • Cite the rationale for targeting HER3 in solid tumors, including advanced breast cancer and EGFR-mutated NSCLC
  • Integrate the latest clinical data regarding the efficacy and safety of HER3-targeting agents into practice as they become available or enroll appropriate patients with advanced breast cancer and EGFR-mutated NSCLC in clinical trials

Target Audience
This activity is intended for oncologists.

Statement of Need
Gains in our understanding of actionable molecular subtypes of NSCLC and breast cancer have led to an active clinical research agenda that has revolutionized treatment. Despite this progress, patients with NSCLC and breast cancer may eventually experience disease progression, highlighting the need for additional treatment options that extend survival. Fortunately, several anti-HER3 therapies are demonstrating promising activity in clinical trials for solid tumors. Oncologists need to be familiar with these investigational therapies targeting HER3 to enroll their eligible patients in appropriate clinical trials and to integrate these therapies into treatment plans once they receive FDA approval.

Providership Statement
Provided by Med-IQ.

Accreditation/Designation Statements
Med-IQ is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.

Med-IQ designates this enduring material for a maximum of 0.5 AMA PRA Category 1 Credit™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Medium/Method of Participation
This is a 0.5-credit CME activity. To receive credit, read the introductory CME material, complete all of the modules, and complete the evaluation, attestation, and post-test, answering at least 70% of the post-test questions correctly.

Initial Release Date: December 30, 2020
Expiration Date: December 29, 2021
Estimated Time to Complete This Activity: 30 minutes

Disclosure Policy
Med-IQ requires any person in a position to control the content of an educational activity to disclose all relevant financial relationships with any commercial interest. The ACCME defines "relevant financial relationships" as those in any amount occurring within the past 12 months, including those of a spouse/life partner, that could create a conflict of interest (COI). Individuals who refuse to disclose will not be permitted to contribute to this CME activity in any way. Med-IQ has policies in place that will identify and resolve COIs prior to this educational activity. Med-IQ also requires faculty to disclose discussions of investigational products or unlabeled/unapproved uses of drugs or devices regulated by the US Food and Drug Administration.

Disclosure Statement
The content of this activity has been peer reviewed and has been approved for compliance. The faculty and contributors have indicated the following financial relationships, which have been resolved through an established COI resolution process, and have stated that these reported relationships will not have any impact on their ability to give an unbiased presentation.

Helena A. Yu, MD
Consulting fees/advisory boards: AstraZeneca, Blueprint Medicines, C4 Therapeutics, Janssen Pharmaceuticals, Inc.

The writer, peer reviewers, and activity planners have no financial relationships to disclose.

Statement of Evidence-Based Content
Educational activities that assist physicians in carrying out their professional responsibilities more effectively and efficiently are consistent with the ACCME definition of continuing medical education (CME). As an ACCME-accredited provider of CME, it is the policy of Med-IQ to review and ensure that all the content and any recommendations, treatments, and manners of practicing medicine in CME activities are scientifically based, valid, and relevant to the practice of medicine. Med-IQ is responsible for validating the content of the CME activities it provides. Specifically, (1) all recommendations addressing the medical care of patients must be based on evidence that is scientifically sound and recognized as such within the profession; (2) all scientific research referred to, reported, or used in CME in support or justification of a patient care recommendation must conform to generally accepted standards of experimental design, data collection, and analysis.

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Contact Information
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The information provided through this activity is for continuing education purposes only and is not meant to substitute for the independent medical judgment of a physician relative to diagnostic and treatment options of a specific patient’s medical condition.

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Acknowledgment of Commercial Support
This activity is supported by an educational grant from Daiichi Sankyo, Inc.

© 2021 Med-IQ, Inc.


Here are the key takeaways from this activity. Deeper insights and evidence, plus an opportunity to receive credit, are available by clicking the "Continue" button below.

  • HER3 has been identified as a driver of tumorigenesis and metastasis in solid tumors
  • Overactivation of HER3 signaling also contributes to cancer treatment resistance, specifically in breast cancer resistance to endocrine therapy and NSCLC resistance to EGFR TKIs
  • Despite its emergence as a key cancer therapeutic target, HER3 cannot be targeted with traditional TKI therapy due to its weak kinase activity
  • Objective responses were limited when first-generation HER3-specific monoclonal antibodies were previously investigated as monotherapies in phase 1 and 2 clinical trials for breast cancer, NSCLC, and other cancer types
  • Several other HER-3 targeting agents are currently in clinical trials for patients with breast cancer or NSCLC, including HER3 antibody-drug conjugates, bispecific antibodies that target both HER3 and HER2, a small-molecule inhibitor of HER2 kinase activity, and an agent that prevents HER3 activation and heterodimerization

View reference list.

Click "Continue" to proceed through this activity and/or receive credit. To receive credit and a certificate, you must complete all of the modules in this activity.

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The information provided through this activity is for continuing education purposes only and is not meant to substitute for the independent medical judgment of a physician relative to diagnostic and treatment options of a specific patient’s medical condition.

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