BACKGROUND: The phase 3 BOLERO-2 study at 18 months’ median follow-up showed that everolimus (EVE) + exemestane (EXE) significantly improved progression-free survival (PFS) vs EXE alone in 724 hormone-receptor–positive (HR+) advanced breast cancer (ABC) patients with recurrence/progression during/after nonsteroidal aromatase inhibitor (NSAI) therapy. A higher rate of grade 3/4 adverse events was noted with EVE + EXE, but was not associated with deterioration in quality of life (QOL) based on the EORTC QLQ-C30 Global Health Status scale. Additional patient-reported post hoc analyses of QOL are reported herein.
METHODS: During BOLERO-2, QOL (EORTC QLQ-C30 and QLQ-BR23) was assessed at baseline and q 6 wk thereafter until progression or discontinuation. Physical, emotional, and social functioning subscales of QLQ-C30 were analyzed. Time to definitive deterioration (TTD) was defined based on either a 5% (protocol specified) or 10-point (more stringent) decrease from baseline for each subscale and analyzed by Kaplan-Meier methods. The difference between treatments was assessed by a log-rank test stratified by randomization factors.
RESULTS: QLQ-C30 compliance was > 80% at week 48. Among the 3 protocol-specified QLQ-C30 subscales, analyses based on a 5% decrease in QOL showed a longer TTD for both physical and emotional functioning in the EVE + EXE group vs EXE alone (log-rank P = .0120 and P = .0277, respectively). The TTD for social functioning was similar in both treatment arms (log-rank P = .3374). Analyses based on a 10-point decrease indicated a longer TTD for physical functioning in the EVE + EXE group (15.2 mo) vs EXE alone (9.7 mo; log-rank P = .0211). The TTDs for emotional and social functioning were similar between EVE + EXE and EXE alone: 13.9 vs 13.8, respectively (log-rank P = .4023), and 11.5 vs 9.5, respectively (log-rank P = .2507).
CONCLUSIONS: The treatment goal for ABC is to maximize clinical benefit with minimal negative effects on QOL. These additional BOLERO-2 QOL analyses confirmed that the more than doubling of PFS with EVE + EXE was accompanied by maintained physical, emotional, and social functioning compared with EXE alone in patients with HR+ ABC progressing after NSAI. Clinical trial information: NCT00863655.
