53O_PR - Efficacy and safety of palbociclib plus fulvestrant in Asian women with hormone receptor-positive (HR+)/human epidermal growth factor-2 negative (H...

Date 19 December 2015
Event ESMO Asia 2015 Congress
Session Breast cancer
Topics Cytotoxic agents
Breast Cancer
Therapy
Biological therapy
Presenter Jungsil Ro
Citation Annals of Oncology (2015) 26 (suppl_9): 16-33. 10.1093/annonc/mdv519
Authors J. Ro1, S. Im2, N. Masuda3, Y. Im4, K. Inoue5, Y. Rai6, R. Nakamura7, J.H. Kim8, K. Zhang9, C. Giorgetti10, P. Schnell11, C. Huang Bartlett12, H. Iwata13
  • 1Center For Breast Cancer, National Cancer Center, 410-769 - Goyang/KR
  • 2Medical Oncology, Seoul National University, SEOUL/KR
  • 3Department Of Surgery, Breast Oncology, NHO Osaka National Hospital, Osaka/JP
  • 4Professor, Division Of Hematology/medical Oncology, Department Of Medicine, Samsung Medical Center, Sungkyunkwan University School Of Medicine, Samsung Medical Center Sungkyunkwan University School of Medicine, Seoul/KR
  • 5Division Of Breast Oncology, Saitama Cancer Center, Saitama/JP
  • 6Principal Of Sagara Hospital, Breast Surgery, Sagara Hospital, Hakuaikai Medical Corporation Sagara Hospital, Kagoshima/JP
  • 7Division Of Breast Surgery, Chiba Cancer Center Hospital, Chiba/JP
  • 8Professor Division Of Hematology/medical Oncology, Seoul National University Bundang Hospital, Gyeonggi-do/KR
  • 9Oncology Clinical Statistics, Pfizer Inc., San Diego/US
  • 10Clinical Oncology, Pfizer, Italy, Milan/IT
  • 11Senior Medical Director, Pfizer Inc., New York/US
  • 12Clinical Oncology, Pfizer Inc., New York/US
  • 13Department Of Breast Oncology, Aichi Cancer Center Hospital, Nagoya/JP

Abstract

Aim/Background

Endocrine resistance is a major clinical issue for patients (pts) with HR + /HER2- breast cancer. The standard of care (SOC) is to re-challenge with ET before switch to chemotherapy (CT). PALOMA3 assessed whether Palbociclib (P) + fulvestrant (F) prolonged progression-free survival (PFS) vs F + placebo (PLB) in pts with HR + /HER2- MBC whose disease had progressed on prior ET. Primary analysis showed median PFS of 9.2 vs 3.8 m (HR 0.42, P < 0.001) in full population (Turner et al NEJM 2015). We present the efficacy and safety in Asian pts with longer follow-up.

Methods

In the Ph 3 PALOMA3 study, 521 pts were randomized 2:1 to P (125 mg/d oral [3 wks drug, 1 wk off]) + F (500 mg, SOC) or PLB + F. Pre-/perimenopausal pts also received goserelin. One previous line of CT for MBC was allowed. Safety assessments occurred at baseline and on D1 per cycle; blood counts every 2 wks for first 2 cycles and on D1 of subsequent cycles. Primary endpoint was investigator-assessed PFS. Secondary endpoints: overall survival, response assessment, patient-reported outcomes, safety. PALOMA3 enrolled pts in Korea and Japan.

Results

By March 2015, 105 Asian pts were randomized (P + F, 74; PLB + F, 31). Baseline characteristics were well balanced. Compared to non-Asians, median age was lower in Asians (52 vs 58 y) and more were pre/perimenopausal (42% vs 15%). 59% of Asian pts had visceral disease, 80% had documented endocrine responsiveness, 34% had 1 line of CT for MBC. Median PFS in Asian pts was not reached for P + F (95% CI 9.2–NR) and 5.8 m for PLB + F (3.5–9.5m) (HR 0.485 [95% CI 0.270–0.869], P = 0.0065). Most common Grade 3/4 adverse events (AEs) in Asian pts were neutropenia (92%) and leucopenia (29%); febrile neutropenia occurred in 4.1% (P + F). No pt stopped P + F due to AEs. 51% of Asian pts had dose reduction due to AEs. 48% were on 100 mg dose.

Conclusions

P + F improved PFS in Asians with HR + /HER2- MBC that progressed on prior ET. The safety profile was consistent with that seen in Non-Asians; neutropenia was the most common AE, and can be managed by dose reduction. P + F may be a reasonable therapeutic option in Asian pts.

Clinical trial identification

NCT01942135

Disclosure

J. Ro: served as a consultant/advisor to Nippon Kayaku (NK) and received travel support from Eisai.

S.-A. Im: consulting fees (e.g. advisory boards): Roche, Novartis, AstraZeneca; Contracted Research: AstraZeneca in 2014. N. Masuda: fees for Non-CME Services received directly from commercial interest or their agents (speaker's Bureaus): Chugai, AstraZenaca Contracted Research Chugai, Novaltis, Pfizer, AstraZeneca, Lilly. K. Inoue: research funding from Pfizer, Lilly, Chugai, Taiho, Daiichi-Sankyo, Parexel. K. Zhang, C. Giorgetti, P. Schnell, C. Huang Bartlett: employee of and owns stock in Pfizer Inc and receive stock options from Pfizer Inc. H. Iwata: honoraria from AstraZeneca, Eisai, Daiichi-Sankyo, Chugai, and Pfizer Inc. All other authors have declared no conflicts of interest.