Nursing Insights: ASCENT-04 Results and Toxicity Management From ASCO

The 2026 American Society of Clinical Oncology (ASCO) Annual Meeting has brought transformative data for the treatment of metastatic triple-negative breast cancer (mTNBC). The global phase 3 ASCENT-04 clinical trial demonstrated that the combination of sacituzumab govitecan (Trodelvy) and pembrolizumab (Keytruda) significantly improves long-term outcomes for patients with previously untreated, PD-L1-positive disease.

To help oncology nurses translate these clinical findings into bedside care, Oncology Nursing News spoke with Sara M. Tolaney, MD, MPH, Chief of the Division of Breast Oncology at Dana-Farber Cancer Institute and Associate Professor of Medicine at Harvard Medical School. Tolaney, a renowned clinical investigator, has been instrumental in the development of antibody-drug conjugates (ADCs) and immunotherapy.

The ASCENT-04 study involved 443 participants across 26 countries, comparing this ADC-immunotherapy duo against the standard chemotherapy plus pembrolizumab. A key takeaway was the improvement in progression-free survival 2 (PFS2), an endpoint closely linked to overall survival. At the two-year follow-up, the PFS2 rate was 63.7% for those receiving the sacituzumab govitecan combination, compared to 45.6% in the chemotherapy arm.

"I think it's really important, when you're starting a patient off on sacitusmab to make sure they're well informed about potential toxicities including diarrhea," Tolaney said. “So, I do make sure patients, for example have loperamide (Imodium) on hand and know how to utilize it if they were to develop diarrhea with sacitusmab."

Beyond gastrointestinal symptoms, the trial data and clinical experience highlight hematologic concerns. How should the care team approach the risk of low white blood cell counts?

"There's a high rate of neutropenia and this could lead to infection,” Tolaney noted. And so it's really important one that the oncologist is monitoring blood counts that we're thinking about use of potential prophylactic growth factor for our patients."

Tolaney also discussed specific "red flags" patients should be taught to report immediately.

"We do warn our patients that if they do get any infectious symptoms or they get low-grade fevers, they do need to call us right away so that we can make sure they're not neutropenic at that time and initiate appropriate therapy."

As sacituzumab govitecan plus pembrolizumab emerges as a potential new standard first-line treatment for PD-L1-positive mTNBC, the role of the oncology nurse in toxicity monitoring and patient education remains more vital than ever.