CHICAGO–Etirinotecan pegol provided a clinically meaningful benefit to patients with late-stage advanced breast cancer, particularly in those with brain and liver metastases, a study presented at the 2015 American Society of Clinical Oncology (ASCO) annual meeting has shown.
Speaking on whether a new chemotherapy option is necessary for the treatment of advanced breast cancer, Edith A. Perez, MD, principal investigator and Deputy Director at Large for May Clinic Cancer Center in Jacksonville, FL, said, “Additional options are needed for patients after treatment with an anthracycline, taxane, and capecitabine.”
For the global, open-label, phase III BEACON study, researchers enrolled 852 patients with advanced breast cancer with or without brain metastases whose disease progressed following treatment with an anthracycline, taxane, and capecitabine.
Participants were randomly assigned 1:1 to receive etirinotecan pegol 145 mg/m2 intravenously over 90 minutes every 3 weeks or treatment of physician’s choice (TPC).
Results showed that median overall survival was 12.4 months (95% CI: 11.0, 13.6) in the etirinotecan pegol groups compared with 10.3 months (95% CI: 9.0, 11.3) in the TPC group (difference=2.1 months; HR=0.872; 95% CI: 0.747, 1.019; P=0.0835).
Subgroup analyses demonstrated that in those with brain metastases, etirinotecan pegol demonstrated an improvement of 5.2 months in median overall survival (10.0 vs. 4.8 months; HR=0.51; P=0.0099) and the proportion of those alive at 12 months was higher in the etirinotecan pegol group (44.4% vs. 19.4%).
Median overall survival was also higher with etirinotecan pegol in patients with liver metastases than TPC (10.9 vs. 8.3 months; HR=0.73; P=0.002).
In regard to safety, grade 3 diarrhea was more common in the etirinotecan pegol arm compared with the TPC arm, while grade 3 neutropenia and peripheral neuropathy occurred more frequently in the TPC arm. All grade diarrhea, nausea, vomiting, decreased appetite, and abdominal pain were more common in the etirinotecan pegol arm.
The study also showed that health-related quality of life scores were higher in the etirinotecan pegol arm than the TPC arm.
Dr. Perez concluded, “The 2.1 month improvement in median overall survival favoring etirinotecan pegol did not reach statistical significance; however, important survival results in predefined subgroups of patients, especially those with a history of brain or liver metastases, deserve further study.”
- Perez EA, Awada A, O’Shaughnessy J, et al. Phase III trial of etirinotecan pegol (EP) versus Treatment of Physician’s Choice (TPC) in patients (pts) with advanced breast cancer (aBC) whose disease has progressed following anthracycline (A), taxane (T) and capecitabine (C): The BEACON study. J Clin Oncol. 2015;33:(suppl; abstr 1001).