BYLieve Trial Supports Use of Alpelisib Plus Fulvestrant for Some Breast Cancers
Posted: Tuesday, July 21, 2020
During the ASCO20 Virtual Scientific Program (Abstract 1006), Hope S. Rugo, MD, of the University of California San Francisco, and colleagues, reported that alpelisib plus fulvestrant demonstrated clinically meaningful efficacy and manageable toxicity after therapy with CDK4/6 inhibition. More than 50% of the 121 patients were alive without disease progression at 6 months, and the median progression-free survival was 7.3 months.
The BYLieve trial is reportedly the first prospective trial to evaluate oral alpelisib and endocrine therapy in patients with PIK3CA-mutated hormone receptor–positive advanced disease who have experienced disease progression on or after therapy with an inhibitor of CDK4/6. Of the 127 patients in cohort A (patients who received a CDK4/6 inhibitor plus an aromatase inhibitor as immediate prior therapy), 121 had centrally confirmed PIK3CA mutations. A total of 70% had received one prior metastatic regimen; the remainder had received at least two prior therapies or none in the metastatic setting. No patients had received fulvestrant as a first-line metastatic agent. Most patients (60%) had secondary endocrine resistance.
The primary endpoint was 6-month progression-free survival. Unadjusted results showed a median progression-free survival of 7.3 months in cohort A of the BYLieve study versus 3.6 months in the real-world cohort. As for safety issues, the most frequent all-grade adverse events were diarrhea (60%), hyperglycemia (58%), nausea (46%), fatigue (29%), decreased appetite (28%), and rash (28%).
Dr. Rugo and colleagues summarized: “Building on findings from SOLAR-1, BYLieve further supports the use of alpelisib plus fulvestrant in patients for the treatment of PIK3CA-mutant, hormone receptor–positive, HER2-negative advanced breast cancer progressing on/after CDK4/6 inhibitor therapy.”
Disclosure: For full disclosures of the study authors, visit coi.asco.org.
