2019 ASCO Annual Meeting!
Session: Breast Cancer—Metastatic
Type: Oral Abstract Session
Time: Tuesday June 4, 9:45 AM to 12:45 PM
Location: Hall D1
Phase III MONALEESA-7 trial of premenopausal patients with HR+/HER2− advanced breast cancer (ABC) treated with endocrine therapy ± ribociclib: Overall survival (OS) results.
2019 ASCO Annual Meeting
J Clin Oncol 37, 2019 (suppl; abstr LBA1008)
Author(s): Sara A. Hurvitz, Seock-Ah Im, Yen-Shen Lu, Marco Colleoni, Fabio Andre Franke, Aditya Bardia, Nadia Harbeck, Louis Chow, Joohyuk Sohn, Keun Seok Lee, Saul Campos Gomez, Rafael Villanueva, Kyung Hae Jung, Arunava Chakravartty, Gareth Hughes, Ioannis Gounaris, Karen Rodriguez-Lorenc, Tetiana Taran, Debu Tripathy; UCLA Jonsson Comprehensive Cancer Center, Los Angeles, CA; Seoul National University Hospital, Cancer Research Institute, Seoul National University College of Medicine, Seoul, South Korea; National Taiwan University Hospital, Taipei, Taiwan; European Institute of Oncology, Milan, Italy; Hospital de Caridade de Ijuí, Ijuí, Brazil; Massachusetts General Hospital Cancer Center, Harvard Medical School, Boston, MA; Brustzentrum der Universität München (LMU), Munich, Germany; Organisation for Oncology and Translational Research, Hong Kong, China; Severance Hospital, Yonsei University Health System, Seoul, South Korea; Center for Breast Cancer, National Cancer Center, Gyeunggi-Do, South Korea; Centro Oncológico Estatal, Instituto de Seguridad Social del Estado de México y Municipios, Toluca, Mexico; Institut Català d'Oncologia, Hospital de Sant Joan Despí Moisès Broggi, Barcelona, Spain; Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea; Novartis Pharmaceuticals Corporation, East Hanover, NJ; The University of Texas MD Anderson Cancer Center, Houston, TX
Background: The phase III MONALEESA-7 study (NCT02278120) is the first dedicated trial of endocrine therapy (ET) ± a cyclin-dependent kinase 4/6 (CDK4/6) inhibitor in premenopausal patients (pts) with hormone receptor–positive (HR+)/HER2− ABC. The study met its primary endpoint of significantly longer progression-free survival (PFS) with ribociclib (RIB; a CDK4/6 inhibitor) + ET vs placebo (PBO) + ET (median, 23.8 vs 13.0 mo; HR, 0.55; P< 0.0001; Tripathy D, et al. Lancet Oncol. 2018). Methods: Premenopausal pts (N=672) with HR+/HER2− ABC were treated with RIB or PBO + goserelin and either a nonsteroidal aromatase inhibitor (NSAI; letrozole or anastrozole) or tamoxifen. This is the 2nd of 3 protocol-specified OS analyses (scheduled to occur after ≈ 189 deaths [75% of the planned total events]). OS was evaluated by Kaplan-Meier methods, and statistical comparison was made by 1-sided stratified log-rank test, with a protocol-defined Lan-DeMets (O’Brien-Fleming) stopping boundary of p < 0.01018 for superior efficacy. Results: The data cutoff for this prespecified interim analysis was Nov 30, 2018, and the median follow-up was 34.6 mo (min, 28.0 mo). At cutoff, 173 pts were continuing study treatment (RIB, n=116; PBO, n=57), and OS was evaluated after 192 deaths (RIB, n=83; PBO, n=109). RIB + ET demonstrated a significantly longer OS than PBO + ET (median, not reached vs 40.9 mo [95% CI, 37.80 mo-not evaluable]; HR, 0.712 [95% CI, 0.54-0.95]; p = 0.00973). The result crossed the prespecified stopping boundary for superior efficacy. Estimated OS rates with RIB + ET vs PBO + ET at 42 mo were 70.2% vs 46.0%, respectively. In pts who received an NSAI (n=495), RIB + ET demonstrated a consistent OS improvement vs PBO + ET (HR, 0.699 [95% CI, 0.50-0.98]). Posttreatment therapy use was balanced between treatment arms (RIB, 68.9%; PBO, 73.2%). Conclusions: RIB + ET demonstrated a clinically and statistically significant longer OS than ET alone in premenopausal pts with HR+/HER2− ABC. This is the first time that a CDK4/6 inhibitor or any targeted agent + ET has demonstrated significantly longer OS vs ET alone as initial endocrine-based therapy. Clinical trial information: NCT02278120