Results from the primary analysis of the open-label, single-arm, phase 2 study BOLERO-4 demonstrated that first-line (1L) EVE + LET was an effective combination with a manageable safety profile in postmenopausal patients with ER+ HER2− ABC. Here, we present results from a predefined subgroup analysis of 1L progression-free survival (PFS) and safety by race (Asian versus non-Asian).
Patients received EVE 10 mg/day + LET 2.5 mg/day until disease progression, unacceptable toxicity, or withdrawal of consent. 1L PFS per local investigator assessment was analyzed overall on the full analysis set (FAS; primary endpoint) and by patient subgroup. This study was not designed to use the SWISH protocol for prevention for stomatitis.
At the data cutoff (December 17, 2016), 44 Asian and 158 non-Asian (Caucasian 72%; Black 4%; Pacific Islander <1%; other 2%) patients had a median PFS and 18- and 24-month KM estimated PFS rates similar to the FAS (Table). In general, all grade adverse events (AEs), regardless of causality or severity, were more common among Asian patients versus non-Asians and the overall population, particularly for stomatitis, weight decreased, anemia, hyperglycemia, decreased appetite, rash and nasopharyngitis. AEs were mostly grade 1–2 in severity and anemia was the most common grade 3–4 AE among both Asian (20%) and non-Asian (8%) patients.FAS RACE N = 202 Asian (n = 44) Non-Asian (n = 158) No. of PFS events, n (%) 108 (53.5) 26 (59.1) 82 (51.9) Median PFS (95% CI), months 22.0 (18.1–25.1) 20.3 (14.8–26.0) 22.0 (17.1–25.7) KM estimated PFS rate (95% CI), % 18-months 58.8 (50.9–65.8) 65.8 (49.1–78.1) 56.7 (47.5–64.8) 24-months 42.9 (35.0–50.5) 44.0 (28.0–58.8) 42.8 (33.7–51.5) CI, confidence interval; KM, Kaplan-Meier
Results from this predefined subgroup analysis were consistent with previously reported BOLERO-4 data, showing that 1L EVE + LET offers clinical benefits irrespective of patient race, with no new safety signals reported. Although some AEs were more common among Asian patients versus non-Asians and the overall population, they were mostly grade 1–2 in severity.
NCT01698918 EudraCT Number (EU number) 2012-003065-17
Novartis Pharmaceuticals Corporation
Novartis Pharmaceuticals Corporation
T. Toyama: Research funding from Eisai, Chugai, Novartis, Nippon Kayaku, Kyowa Hakko Kirin, Daiichi-Sankyo, Takeda, J. Jeong: Research funding from Dong-A, Boryung, LG Life Sciences, Antigen; Honoraria from Roche, Alvogen, Novartis, Pfizer, Covidien, V. Sriuranpong: Honoraria from Novartis, Roche, MSD, Sanofi, Eisai, AstraZeneca, H. Iwase: Research funding from AstraZeneca, Chugai-Roche, Taiho, Daiichi-Sankyo, Novartis, Pfizer, Kyowa Hakko-Kirin, Eisai; Honoraria from AstraZeneca, Novartis, Takeda, Chugai-Roche. C. Arce: Novartis employee, A. Ridolfi: Novartis Pharma SAS employee, C. Lin: Novartis employee and stocks, M. Royce: Research funding from Novartis; Consultant for Celltrion, BCI; Honoraria from Novartis, Syndax, F. Cardoso: Research funding for clinical trials by institution; consultant for Astellas/Medivation, AstraZeneca, Celgene, Daiichi-Sankyo, Eisai, GE Oncology, Genentech, GSK, MacroGenics, Merck, Merus BV, Novartis, Pfizer, Pierre-Fabre, Roche, Sanofi, Teva
All other authors have declared no conflicts of interest.