253P - Abemaciclib plus fulvestrant in patients (pts) with HR+/HER2- endocrine therapy naïve (EN) advanced breast cancer - an exploratory analysis of MONA...

Date 11 September 2017
Event ESMO 2017 Congress
Session Poster display session
Topics Anti-Cancer Agents & Biologic Therapy
Breast Cancer, Metastatic
Breast Cancer
Presenter Peter Kaufman
Citation Annals of Oncology (2017) 28 (suppl_5): v74-v108. 10.1093/annonc/mdx365
Authors P.A. Kaufman1, H. Iwata2, P. Nikolinakos3, J.T. Beck4, H. Koh5, J.L. Gonzalez-Trujillo6, Y. Lin7, S. Barriga8, D. Headley9, N. Bourayou10, A. Llombart Cussac11, G.W. Sledge Jr.12
  • 1Medicine, Section Of Oncology, Norris Cotton Cancer Center Dartmouth-Hitchcock Medical Center, 03756 - Lebanon/US
  • 2Breast Oncology, Aichi Cancer Center Hospital, 467-8681 - Nagoya/JP
  • 3Hematology And Medical Oncology, University Cancer & Blood Center, LLC, 30607 - Athens/US
  • 4Department Of Medicine, Highland Oncology Group, 72703 - Fayetteville/US
  • 5Department Of Medical Oncology, Kaiser Permanente Medical Group, Bellflower/US
  • 6Oncology, Fundacion Rodolfo Padilla AC, Leon Guanajuato/MX
  • 7Global Statistical Sciences, Eli Lilly and Company, Indianapolis/US
  • 8Oncology Clinical Development, Eli Lilly and Company, Madrid/ES
  • 9Oncology Clinical Development, Eli Lilly and Company, Indianapolis/US
  • 10Oncology Clinical Development, Eli Lilly and Company, Paris/FR
  • 11Medical Oncology Service, Hospital Arnau Vilanova, Valencia/ES
  • 12Department Of Medicine, Stanford University, Stanford/US

Abstract

Background

MONARCH 2 demonstrated that the addition of abemaciclib, dosed on a continuous schedule at 150 mg twice daily, to fulvestrant (F) significantly improved progression-free survival (PFS) and objective response rate (ORR) compared to placebo (P) plus F (PFS hazard ratio [HR], 0.553, P

Methods

Pts were randomized 2:1 to receive abemaciclib or P + F (500 mg, per label). Pre/perimenopausal women received a gonadotropin-releasing hormone agonist. Pts were not allowed to have had chemotherapy in the advanced setting. Pts were stratified by metastatic site (visceral, bone only, other). The primary endpoint for this analysis was investigator-assessed PFS which was described using the Kaplan-Meier method and a Cox model.

Results

Forty-four EN pts were randomized to abemaciclib + F (N = 28) or P + F (N = 16). 46% of pts presented with visceral disease, 77% with measurable disease, and 82% were postmenopausal. At the time of the analysis, 18 pts were still on treatment (13 [46.4%] in the abemaciclib + F arm and 5 [31.3%] in the P + F arm). 18 PFS events were observed (9 [32.1%] in the abemaciclib + F arm and 9 [56.3%] in the P + F arm). The median PFS had not been reached in the abemaciclib + F arm and was 23.1 months in the P + F arm (stratified HR, 0.454; 95% CI: 0.179, 1.154). The ORR in pts with measurable disease was 60.0% (5% complete response [CR]) in the abemaciclib + F arm and 57.1% (0% CR) in the P + F arm. The most common adverse events were diarrhea, nausea, fatigue, and neutropenia. Diarrhea generally occurred in the early cycles and was managed with dose adjustment and conventional anti-diarrheal medication.

Conclusions

In this exploratory cohort of EN pts, the addition of abemaciclib to fulvestrant demonstrated a comparable increase in PFS and consistent safety results to those observed in the ITT population in MONARCH 2.

Clinical trial identification

NCT02107703

Legal entity responsible for the study

Eli Lilly and Company

Funding

Eli Lilly and Company

Disclosure

P.A. Kaufman: Consulting/Advisory: Galena Biopharma, Amgen; Research Funding: Eli Lilly and Company. P. Nikolinakos: Advisory board: AstraZeneca. J.T. Beck: My institution receives research grants as part of this study. J.L. Gonzalez-Trujillo: Contract with Lilly, Bristol-Myers Squibb, Roche, Pierre Fabre, Astra for make a corporate-sponsored research. Advisory board for Bristol-Myers Squibb, MSL, Novartis. Speaker for Bristol-Myers Squibb, Novartis. Y. Lin, N. Bourayou: Employment and Stock Ownership: Eli Lilly and Company. S. Barriga: Employment Eli Lilly and Company. D. Headley: Employment and Stock Ownership: Eli Lilly and Company; Stock Ownership: AstraZeneca. A. Llombart Cussac: Honoraria: Roche, Novartis, Pfizer; Consulting/Advisory: Roche, AstraZeneca, Eli Lilly and Company; Research funding: Pfizer, Roche; Travel funds: Roche, Celgene. G.W. Sledge Jr.: Leadership, Stock: Syndax; Honoraria: Symphogen; Consulting/Advisory: Symphogen, Coherus Biosciences, Radius Health, Peregrine Pharmaceuticals, Taiho Pharmaceutical; Research Funding: Roche (Inst); Travel funds: Nektar, Radius Health, Taiho Pharmaceutical. All other authors have declared no conflicts of interest.