[ESMO 2024] Breast Cancer Patient Who Lived '8 Months' Survives Over 1 Year in 90% After Receiving 'Enhertu'

Breast Cancer Patients, When It Spreads to the Brain
Half Survive Less Than 8 Months

AZ·DS Jointly Developed ADC 'Enhertu'
Over 90% of Patients Survive More Than 1 Year Regardless of Brain Metastasis

Leading the global wave of antibody-drug conjugates (ADC) and known as the 'miracle anticancer drug,' Enhertu has once again demonstrated its innovative efficacy. In clinical trials, consistent efficacy was confirmed regardless of brain metastasis status in breast cancer patients, half of whom previously did not survive beyond eight months when the cancer spread to the brain.

Nancy Lin, Deputy Director of the Dana-Farber Cancer Institute in the United States, presented the primary results of the 'DESTINY-Breast12' clinical trial, conducted to demonstrate the efficacy of the antibody-drug conjugate (ADC) 'Enhertu' regardless of brain metastasis status in breast cancer patients, at the 2024 European Society for Medical Oncology (ESMO) conference held in Barcelona, Spain, on the 13th (local time).
[Photo by Lee Chunhee]

Nancy Lin, Deputy Director of the Dana-Farber Cancer Institute in the United States, stated on the first day of the 2024 European Society for Medical Oncology (ESMO) conference held in Barcelona, Spain, on the 13th (local time), during a presentation titled "First Results of the DESTINY-Breast12 Clinical Trial of Enhertu in HER2-Positive Advanced and Metastatic Breast Cancer Patients Regardless of Brain Metastasis Status," that "the results of this clinical trial support the use of Enhertu in HER2-positive metastatic breast cancer patients," adding, "It showed a high and consistent 12-month overall survival rate regardless of brain metastasis status."

Cancer gradually grows and metastasizes to distant organs such as the brain, liver, and bones through blood vessels or lymphatic vessels. It is known that 10-15% of patients diagnosed with metastatic breast cancer experience brain metastasis. In particular, when the HER2 mutation, one of the mutations cancer cells create to evade the body's immune system, appears, the probability of brain metastasis rises to 30-50%.

The problem is that prognosis rapidly worsens when brain metastasis occurs. Currently, half of the patients with brain metastasis are known not to survive beyond eight months. Moreover, brain magnetic resonance imaging (MRI) must be performed to observe brain metastasis, but since it is not done frequently, metastasis is often confirmed only after it has significantly progressed. If neurological damage has already occurred, recovery becomes difficult, and even surgery often fails to treat the condition. When cancer metastasizes to the meninges, treatment becomes even more challenging, and many patients die within a month.

AstraZeneca-Daiichi Sankyo's antibody-drug conjugate (ADC) 'Enhertu' (generic name: trastuzumab deruxtecan)
[Photo by Daiichi Sankyo Korea]

Enhertu, an ADC jointly developed by AstraZeneca (AZ) and Daiichi Sankyo, is recognized as a drug leading the global ADC trend by expanding its treatment scope to various cancer types after proving groundbreaking efficacy in breast cancer. Although Enhertu had demonstrated efficacy in previous clinical trials involving breast cancer patients, including those with brain metastases, this trial was conducted to specifically verify whether Enhertu is effective in patients with active brain metastases. Accordingly, this clinical trial formed cohorts by dividing a total of 504 patients into approximately half with brain metastases (263 patients) and half without brain metastases (241 patients).

Enhertu succeeded in enabling more than 90% of patients to survive for over one year, not only in those without brain metastases but also in those with brain metastases. Specifically, 90.3% of patients with brain metastases and 90.6% of those without brain metastases survived beyond one year. Additionally, 61.6% of patients with brain metastases showed no further cancer progression for one year. Deputy Director Lin noted that half of the patients with brain metastases in this trial were expected to have no further cancer progression for about 17.3 months (median progression-free survival, mPFS).

Regarding safety, adverse reactions were observed at manageable levels similar to previous Enhertu clinical trials, showing consistent levels regardless of brain metastasis status.

On the 13th (local time) at the 2024 European Society for Medical Oncology (ESMO) held in Barcelona, Spain, the 12-month overall survival (OS) results of Enhertu in breast cancer patients with or without brain metastases were presented. Among patients with brain metastases, 90.3% (left), and among those without brain metastases, 90.6% survived beyond 12 months, demonstrating that Enhertu showed consistent OS results regardless of the presence of brain metastases.
[Photo by Lee Chunhee]

Deputy Director Lin stated, "Up to 50% of HER2-positive metastatic breast cancer patients experience brain metastases, which significantly affect quality of life and prognosis," adding, "This data will help characterize the clinical benefits and safety of Enhertu in these patients and assist in making treatment decisions."