ASCENT-07 and Triple-Negative Breast Cancer Advances

Dr. Nunnery discusses ASCENT-07, which moved SG earlier in the treatment sequence for HR-positive disease, allowing patients progressing on endocrine therapy to receive the ADC immediately rather than requiring intervening chemotherapy. Surprisingly, this frontline comparison against standard chemotherapy yielded negative results without statistically significant PFS improvement.

Dr. Iyengar expresses puzzlement at the negative ASCENT-07 results, questioning whether the incremental benefit of SG versus standard chemotherapy in the upfront setting was too small for statistical detection. This contrasts with T-DXd's proven efficacy from DESTINY-Breast06 in the frontline post-endocrine therapy setting.

For HER2-null patients ineligible for T-DXd, the approach involves chemotherapy before accessing TROP2-targeted ADCs. Dr. Nunnery favors oral capecitabine for its convenience, familiar administration route for patients accustomed to oral endocrine therapy, and absence of alopecia concerns.

Shifting to triple-negative breast cancer (TNBC), the panel discusses exciting developments with multiple ADC options emerging from recent trials. ASCENT-03 studied SG versus standard chemotherapy in frontline metastatic TNBC for patients ineligible for immunotherapy (typically PD-L1 negative), demonstrating significant PFS benefit.

ASCENT-04 evaluated SG combined with pembrolizumab versus standard chemotherapy plus pembrolizumab for PD-L1 positive patients eligible for immunotherapy, also showing significant PFS improvement.

Dr. Nunnery emphasizes the clinical significance of improving first-line therapy duration for patients with TNBC, who historically experience worse long-term outcomes. Any advancement in frontline disease control represents meaningful progress for this challenging patient population.