Abstract 269P
Background
Palbociclib (P) was the first CDK 4/6 inhibitor approved in Europe for hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced/metastatic breast cancer (aBC/mBC) in combination with an Aromatase Inhibitor (AI) or Fulvestrant (F). Data were collected as part of the multi-country Ibrance Real World Insights (IRIS) study.
Methods
A retrospective chart review of postmenopausal women with HR+/HER2- aBC/mBC was conducted in 5 countries between July 2019 – March 2020. Clinical characteristics, treatment patterns and clinical outcome data were abstracted. Progression-free rate (PFR) and survival rate (SR) at 12 and 24 months were estimated via Kaplan-Meier analysis.
Results
Medical records of 1017 patients (pts) receiving palbociclib combinations in Italy (n=260), the UK (n=255), Germany (n = 251), Belgium (n=151) and Switzerland (n=100) were abstracted by 131 physicians (n= 33, 34, 35, 9, 20 respectively). Overall, 582 pts received P+AI and 435 pts P+F. Mean (SD) age at palbociclib initiation was 61.8 (10.8) years for P+AI and 64.1 (10.2) years for P+F pts. Performance status (ECOG) at palbociclib initiation was mostly 0 (42.8% P+AI; 29.2% P+F pts) or 1 (45.4% P+AI; 57.9% P+F pts). Of those with metastases (P+AI n=532, P+F n=379) 49.1% P+AI and 46.2% P+F had visceral disease; 41.4% P+AI and 37.2% P+F had bone only metastases. At the time of data collection, most pts were still on treatment (80.2% P+AI; 80.0% P+F pts). Median duration of follow-up from palbociclib initiation was 10.0 months for P+AI and 7.2 months P+F pts. Most pts initiated at a dose of 125 mg/day (92.8% P+AI and 87.4% P+F pts). Of those initiating at 125 mg/day, dose reductions occurred in 17.4% P+AI and 11.6% P+F pts. PFR for P+AI at 12 months was 88.2% and 62.6% at 24 months; SR was 97.7% at 12 months and 93.2% at 24 months. PFR for P+F at 12 months was 81.1% and 55.2% at 24 months; SR at 12 months was 96.8% and 85.2% at 24 months.
Conclusions
In the real-world setting, across 5 European countries, palbociclib has low levels of dose reductions and demonstrated effectiveness by the progression free and survival rates at 12 and 24 months, however further follow-up is needed for mature outcomes data.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
Pfizer Inc.
Funding
Pfizer Inc.
Disclosure
G. Taylor-Stokes: Full/Part-time employment, Employee of Adelphi Real World, who were paid consultants to Pfizer in connection with the development of this abstract: Adelphi Real World. L. Zhan: Shareholder/Stockholder/Stock options, Full/Part-time employment: Pfizer Inc. K.L. Mycock: Full/Part-time employment, Employee of Adelphi Real World, who were paid consultants to Pfizer in connection with the development of this abstract: Adelphi Real World. G. Milligan: Full/Part-time employment, Employee of Adelphi Real World, who were paid consultants to Pfizer in connection with the development of this abstract: Adelphi Real World. K. Hart: Full/Part-time employment, Employee of Adelphi Real World, who were paid consultants to Pfizer in connection with the development of this abstract: Adelphi Real World. D. Mitra: Shareholder/Stockholder/Stock options, Full/Part-time employment: Pfizer Inc.