The Breast: Published: September 27, 2022
Background
Breast cancer is the most common malignancy and the second
leading cause of cancer-related mortality in Spanish women. Ribociclib in
combination with endocrine therapy (ET) has shown superiority in prolonging
survival in patients with hormone receptor-positive (HR+), human epidermal
growth factor receptor 2-negative (HER2−) advanced breast cancer (ABC) vs. ET
alone.
Methods
CompLEEment-1 is a single-arm, open-label phase 3b trial
evaluating ribociclib plus letrozole in a broad population of patients with HR+,
HER2– ABC. The primary endpoints were safety and tolerability. Here we report
data for Spanish patients enrolled in CompLEEment-1.
Results
A total of 526 patients were evaluated (median follow-up:
26.97 months). Baseline characteristics showed a diverse population with a
median age of 54 years. At study entry, 56.5% of patients had visceral
metastases and 8.7% had received prior chemotherapy for advanced disease. Rates
of all-grade and Grade ≥3 adverse events (AEs) were 99.0% and 76.2%,
respectively; 21.3% of patients experienced a serious AE, and 15.8% of AEs led
to treatment discontinuation. AEs of special interest of neutropenia, increased
alanine aminotransferase, increased aspartate aminotransferase and QTcF
prolongation occurred in 77.8%, 14.8%, 11.4% and 4.0% of patients,
respectively. Patients aged >70 years experienced increased rates of
all-grade and Grade ≥3 neutropenia and anemia. Efficacy results were consistent
with the global study.
Conclusions
Results from Spanish patients enrolled in CompLEEment-1 are
consistent with global data showing efficacy and a manageable safety profile
for ribociclib plus letrozole treatment in patients with HR+, HER2− ABC,
including populations of interest (NCT02941926).
