Aditya Bardia, MD, MPH, Massachusetts General Hospital, Boston, Massachusetts, discussed results from the TROPION-Breast01 trial which compared datopotamab deruxtecan, a TROP-2 directed antibody drug conjugate, with standard chemotherapy in endocrine-resistant metastatic breast cancer.

Results showed datopotamab deruxtecan improved efficacy and quality of life compared to standard chemotherapy, with favorable safety.

Dr Bardia first shared these results at the 2023 San Antonio Breast Cancer Symposium.

Transcript:

Hello, I'm Aditya Bardia, breast medical oncologist at Massachusetts General Hospital, excited to be at San Antonio Breast Cancer Symposium 2023. We presented the updated results from TROPION-Breast01, a global phase 3 trial looking at [datopotamab deruxtecan] Dato-DXd, a TROP–2-directed antibody drug conjugate, plus a standard chemotherapy for patients with endocrine-resistant metastatic breast cancer.

As a brief background, patients with endocrine-resistant, metastatic breast cancer often receive chemotherapy, but chemotherapy can be associated with side effects: myelosuppression, peripheral neuropathy, and other [adverse events] AEs. Clinically, there's a need for better therapies for patients with endocrine-resistant metastatic breast cancer. Dato-DXd, or datopotamab deruxtecan, is a TROP–2-directed antibody drug conjugate that selectively delivers payload to cancer cell and thus has lower toxicity in principle as compared to chemotherapy, but higher efficacy because it selectively delivers payload to cancer cells.

At San Antonio Breast Cancer Symposium, we saw results related to progression-free survival by investigator assessment, subgroup analyses, safety, as well as quality of life data. In terms of efficacy, we saw improvement in investigator-assessed progression-free survival with Dato-DXd, median progression-free survival about 7 months versus about 4.5 months with standard chemotherapy. About 2-and-a-half-month median improvement in progression-free survival as per investigator assessment. In terms of subgroup results by prior duration of CDK4/6 inhibitors or brain metastases, in all the subgroups the results were fairly consistent. In terms of safety, patients who received Dato-DXd had lower grade 3 AEs as compared to standard chemotherapy— it's not that the drug does not have AEs, patients did have mucositis as the most common AE, but they were mostly grade 1 or grade 2; the incidence of grade 3 AEs was low.

For some patients, grade 1/2 mucositis can be problematic as well so, the team looked at quality of life data related to Dato-DXd versus standard chemotherapy. Patients who received Dato-DXd had longer time to deterioration in their global quality of life as compared to standard chemotherapy. Similarly, if you look at physical functioning or pain, the time to deterioration was longer with Dato-DXd compared to standard chemotherapy.

In totality, we saw improvement in efficacy, favorable safety profile, and improvement in quality of life with Dato-DXd as compared to standard chemotherapy. If FDA-approved, this will be another option for our patients with endocrine-resistant metastatic breast cancer that has both superior efficacy as well as better safety and quality of life profile as compared to standard chemotherapy.

Source:

Bardia A, Jhaveri K, Im SA, et al. Randomized phase 3 study of datopotamab deruxtecan vs chemotherapy for patients with previously-treated inoperable or metastatic hormone receptor-positive, HER2-negative breast cancer: Results from TROPION-Breast01. Presented at San Antonio Breast Cancer Symposium; December 5-9, 2023; San Antonio, Texas. Abstract GS02-01