Effect of palbociclib plus endocrine therapy on time to chemotherapy across subgroups of patients with hormone receptor‒positive/human epidermal growth factor receptor 2‒negative advanced breast cancer: Post hoc analyses from PALOMA-2 and PALOMA-3
Hope S. Rugo,
Seock-Ah Im,
Anil A. Joy,
Yaroslav Shparyk,
Janice M. Walshe,
Bethany Sleckman,
Sherene Loi,
Kathy Puyana Theall,
Sindy Kim,
Xin Huang,
Eustratios Bananis,
Reshma Mahtani,
Richard S. Finn,
Véronique Diéras
Affiliations
Hope S. Rugo
University of California, San Francisco, Helen Diller Family Comprehensive Cancer Center, Department of Medicine (Hematology/Oncology), 1825 4th Street, 3rd Floor, Box 1710, San Francisco, CA, 94158, USA; Corresponding author. University of California, San Francisco, Helen Diller Family Comprehensive Cancer Center, Department of Medicine (Hematology/Oncology), 1825 4th Street, 3rd Floor, Box 1710, San Francisco, CA, 94158-1710, USA.
Seock-Ah Im
Seoul National University Hospital, Cancer Research Institute, Seoul National University College of Medicine, Seoul National University, 101 Daehak-ro, Jonro-gu, Seoul 03080, Republic of Korea
Anil A. Joy
Cross Cancer Institute, University of Alberta, 11560 University Ave NW, Edmonton, AB T6G1Z2, Canada
Yaroslav Shparyk
Lviv State Oncologic Regional Treatment and Diagnostic Center, Lviv, Ukraine
Janice M. Walshe
Cancer Trials Ireland, St Vincent's University Hospital, Elm Park, Dublin 4, Ireland
Bethany Sleckman
Mercy Hospital St. Louis, 607 S New Ballas Road, Suite 3300, St. Louis, MO, 63141, USA
Sherene Loi
Peter MacCallum Cancer Centre, University of Melbourne, Australia
Kathy Puyana Theall
Pfizer Oncology, 300 Technology Square, Cambridge, MA 02139, USA
Sindy Kim
Pfizer Inc, 10555 Science Center Dr, San Diego, CA 92121, USA
Xin Huang
Pfizer Inc, 10555 Science Center Dr, San Diego, CA 92121, USA
Eustratios Bananis
Pfizer Inc, 235 E 42nd St, New York, NY, 10017, USA
Reshma Mahtani
Miami Cancer Institute, Baptist Health South Florida, Member, Memorial Sloan Kettering Cancer Alliance, 1228 South Pine Island Road, Plantation, FL, 33324, USA
Richard S. Finn
David Geffen School of Medicine, 2825 Santa Monica Blvd, Suite 200, Santa Monica, CA, 90404, USA
Véronique Diéras
Unicancer Centre Eugène Marquis, Avenue de la Bataille Flandres-Dunkerque, CS 44229, 35042, Rennes Cedex, France
Background: Previous analyses from the PALOMA-2 and PALOMA-3 studies showed that palbociclib (PAL) plus endocrine therapy (ET) prolongs time to first subsequent chemotherapy (TTC) versus placebo (PBO) plus ET in the overall population of patients with hormone receptor‒positive/human epidermal growth factor receptor 2‒negative (HR+/HER2−) advanced breast cancer (ABC). Here, we evaluated TTC in relevant patient subgroups. Methods: These post hoc analyses evaluated TTC by subgroup using data from 2 randomized, phase 3 studies of women with HR+/HER2− ABC. In PALOMA-2, postmenopausal patients previously untreated for ABC were randomized 2:1 to receive PAL (125 mg/day, 3/1-week schedule) plus letrozole (LET; 2.5 mg/day; n = 444) or PBO plus LET (n = 222). In PALOMA-3, premenopausal or postmenopausal patients whose disease had progressed after prior ET were randomized 2:1 to receive PAL (125 mg/day, 3/1-week schedule) plus fulvestrant (FUL; 500 mg; n = 347) or PBO plus FUL (n = 174). Results: First subsequent chemotherapy was received by 35.5% and 56.2% in PALOMA-2 and PALOMA-3 after progression on palbociclib plus ET or placebo plus ET. Across all subgroups analyzed, the median progression-free survival (PFS) was longer in the PAL plus ET arm than the PBO plus ET arm. TTC was longer with PAL plus ET versus PBO plus ET across the same patient subgroups in both studies. Conclusions: Across all subgroups, PAL plus ET versus PBO plus ET had longer median PFS and resulted in prolonged TTC in both the PALOMA-2 and PALOMA-3 studies.Pfizer Inc (NCT01740427, NCT01942135).
