Abstract 4401
Background
In Feb 2015, palbociclib plus letrozole (P+L) became the first cyclin-dependent-kinase 4/6 inhibitor approved for mBC/aBC in the US. Until now, long-term outcomes studies have included a limited number of patients receiving P+L. The objective of this study is to describe real-world patient characteristics and clinical effectiveness associated with P+L as initial endocrine-based therapy use 4 years post approval.
Methods
Adult postmenopausal women diagnosed with metastatic HR+/HER2- breast cancer who initiated P+L as first-line therapy on or after 2/3/2015 were identified by providers in the Cardinal Health Oncology Provider Extended Network, including 1800 oncologists/hematologists in the US. A subset of providers abstracted data related to patient characteristics and clinical outcomes including disease response and disease progression into an electronic case report from (eCRF). Data were abstracted from the time of initiation of P+L through Feb 2019 (or end of follow up/death). Providers were shown response classification schema corresponding to RECIST v1.1 and asked to indicate the patient’s best response if recorded. The objective response rates (ORR – incl. complete response [CR] and partial response [PR]), clinical benefit rates (CBR – incl. CR+PR+stable disease [SD] >24 wks), and progression-free survival (PFS) rate at 12-month were reported. Each eCRF was reviewed by independent clinical staff; source data was verified on 10% of the patients.
Results
31 providers submitted 202 eCRFs, of which, 193 were eligible. Median follow-up from 1L P+L initiation was 15.4 months, 45.6% of patients had discontinued P+L at data cut-off. Table shows key patient characteristics and ORR, CBR, and PFS rate at 12-month, each showing benefit of 1L P+L in the real-world.Table:
338P
N = 193 | All |
---|---|
Mean age at diagnosis, yrs | 62.7 |
Non-Hispanic white, % | 74.6 |
Black/African-American, % | 17.1 |
ECOG-PS 0/1, % | 89.6 |
N0, % | 22.8 |
Visceral mets, % | 51.3 |
Bone only mets, % | 25.4 |
ORR, % | 65.8 |
CR | 9.8 |
PR | 56.0 |
CBR†, % | 88.0 |
CR | 12.7 |
PR | 61.3 |
SD† | 14.0 |
12-month PFS, % | 74.5 |
†Excluding 43 patients with duration of treatment <24 wks
Conclusions
These real-world data demonstrate the benefit of 1L P+L 4 years post approval in the US and support the clinical benefit of 1L P+L reported in randomized clinical trials.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Pfizer Inc.
Funding
Pfizer Inc.
Disclosure
J. Kish: Full / Part-time employment: Cardinal Health; Advisory / Consultancy, Paid consultant in connection with the development of this abstract: Pfizer Inc. J. Trocio: Shareholder / Stockholder / Stock options, Full / Part-time employment: Pfizer Inc. T. Miller: Full / Part-time employment: Cardinal Health; Advisory / Consultancy, Paid consultant in connection with the development of this abstract: Pfizer Inc. D. Nero: Full / Part-time employment: Cardinal Health; Advisory / Consultancy, Paid consultant in connection with the development of this abstract: Pfizer Inc. D. Liassou: Full / Part-time employment: Cardinal Health; Advisory / Consultancy, Paid consultant in connection with the development of this abstract: Pfizer Inc. X. Liu: Shareholder / Stockholder / Stock options, Full / Part-time employment: Pfizer Inc. L. McRoy: Shareholder / Stockholder / Stock options, Full / Part-time employment: Pfizer Inc. B. Feinberg: Full / Part-time employment: Cardinal Health; Advisory / Consultancy, Paid consultant in connection with the development of this abstract: Pfizer Inc.
Resources from the same session
3034 - Efficacy and safety of neoadjuvant chemotherapy plus trastuzumab and pertuzumab in non-metastatic HER2-positive breast cancer in real life: NEOPEARL STUDY
Presenter: Maria Agnese Fabbri
Session: Poster Display session 2
Resources:
Abstract
4772 - Real world comparison of the impact of adjuvant capecitabine in women with high-risk triple-negative breast cancer after neoadjuvant chemotherapy
Presenter: Maysa Vilbert
Session: Poster Display session 2
Resources:
Abstract
5627 - Influence of age on the indication of adjuvant chemotherapy in early breast cancer using Oncotype DX. An analysis of 240 patients treated in the Institut Catala d’Oncologia (ICO) hospitals
Presenter: Sabela Recalde
Session: Poster Display session 2
Resources:
Abstract
3917 - Impact of delayed neoadjuvant systemic chemotherapy on survival among breast cancer patients
Presenter: Mariana Chavez Mac Gregor
Session: Poster Display session 2
Resources:
Abstract
2246 - Clinical Confirmation of Higher Exposure to Niraparib in Tumor vs Plasma in Patients With Breast Cancer
Presenter: Laura Spring
Session: Poster Display session 2
Resources:
Abstract
581 - The rationale for the effectiveness of systemic treatment of breast cancer depending on the body weight index
Presenter: Mohammad Hojouj
Session: Poster Display session 2
Resources:
Abstract
5327 - Response to neoadjuvant chemotherapy in HER2 non-overexpressing breast cancer subtypes
Presenter: Silvia Mihaela Ilie
Session: Poster Display session 2
Resources:
Abstract
3613 - Pre-specified interim analysis of the SAFE trial (NCT2236806): a 4-arm randomized, double-blind, controlled study evaluating the efficacy and safety of cardiotoxicity prevention in non-metastatic breast cancer patients treated with anthracyclines with or without trastuzumab.
Presenter: Lorenzo Livi
Session: Poster Display session 2
Resources:
Abstract
3736 - Safety of hypofractionated whole breast irradiation after conservative surgery for patients aged less than 60 years: a multi-center comparative study.
Presenter: Icro Meattini
Session: Poster Display session 2
Resources:
Abstract
5085 - Usefulness of NT-ProBNP as a biomarker of cardiotoxicity in breast cancer patients treated with trastuzumab
Presenter: Isabel Blancas López-Barajas
Session: Poster Display session 2
Resources:
Abstract