Enhertu® Metastatic Breast Cancer Trial Results DESTINY-Breast06

Guidelines + Trials Spotlight - Enhertu Metastatic Breast Cancer

According to the National Institutes of Health (NIH), around 13% of women will receive a cancer diagnosis at some stage in their lives. In 2021, an estimated 3,972,256 women were living with cancer in the United States. The most prevalent cancer subtype is HR+/HER2-, with an age-adjusted rate of 90 new cases per 100,000 women, based on data from 2017 to 2021. This underscores the critical need for advancing treatment options.

In response to this critical need, we are going to look at the results of the DESTINY-Breast06 Phase III trial which have revealed promising outcomes, indicating that Enhertu (fam-trastuzumab deruxtecan-nxki) has shown a significant improvement in progression-free survival (PFS) compared to standard-of-care chemotherapy. This improvement was both statistically significant and clinically meaningful in the primary trial population, which consisted of patients with HR-positive, HER2-low (IHC 1+ or 2+/ISH-) metastatic cancer who had undergone one or more lines of endocrine therapy. These findings suggest that Enhertu may offer a more effective treatment option for this patient population. Below is a brief overview of the study:

A Phase 3, Randomized, Multi-center, Open-label Study of Trastuzumab Deruxtecan (T-DXd) Versus Investigator’s Choice Chemotherapy in HER2-Low, Hormone Receptor Positive Breast Cancer Patients Whose Disease Has Progressed on Endocrine Therapy in the Metastatic Setting (DESTINY-Breast06)

Study Details | Source

Sponsor: AstraZeneca
The study aims to evaluate the efficacy, safety and tolerability of trastuzumab deruxtecan compared with investigator’s choice chemotherapy. This study aims to see if trastuzumab deruxtecan allows patients to live longer without the cancer getting worse, or simply to live longer, compared to patients receiving standard of care chemotherapy. This study is also looking to see how the treatment and the cancer affects patients’ quality of life.
Interventions: Drug: Trastuzumab deruxtecan, Drug: Capecitabine, Drug: Paclitaxel, Drug: Nab-Paclitaxel
Primary Outcomes Measures: Progression Free Survival (PFS) – in HR+, HER2-low population [Until progression or death, assessed up to approximately 60 months]
Defined as time from date of randomization until the date of objective radiological disease progression by blinded independent central review (BICR) assessment according to RECIST 1.1 or death.
Key secondary endpoints include OS in patients with HER2-low expression and PFS by BICR and OS in the overall trial population (HER2-low and HER2-ultralow). Other secondary endpoints include objective response rate, duration of response, time to first subsequent treatment or death, time to second subsequent treatment or death and safety. Analysis of the HER2-ultralow subgroup was not powered to demonstrate statistical significance.

Enhertu is a specifically engineered HER2-directed DXd antibody drug conjugate (ADC) discovered by Daiichi Sankyo and being jointly developed and commercialized by AstraZeneca and Daiichi Sankyo. The safety profile of Enhertu was consistent with previous breast cancer clinical trials with no new safety signals identified.

The latest data will be showcased at an Industry Expert Theater during the 2024 ASCO Annual Meeting on June 3rd, 2024. The presentation, titled “HER2 Expression Informs Eligibility for ENHERTU^® (fam-trastuzumab deruxtecan-nxki) in 2L HER2+ or HER2-Low mBC,” will provide valuable insights and results. We strongly encourage attendance at this presentation to stay informed on the most recent information.

Will the results of this trial impact the latest ASCO guidelines – Systemic Treatment of Patients with Metastatic Breast Cancer? We value your input and encourage you to share your thoughts. Don’t forget to sign up for alerts and stay informed on the latest published guidelines and articles.