Abstract 234P
Background
PALBOSPAIN is an observational, multicenter study to evaluate real-world practice patterns and outcomes of first-line treatment for advanced breast cancer (ABC) with Palbociclib. Results from real-world progression free survival (rwPFS) and overall survival (OS) in the total population and according to endocrine sensitivity have been previously reported. Here, we provide subgroup analysis according to age, sites and number of metastatic locations, menopausal status, and dose received.
Methods
Patients diagnosed with HR+/HER2- ABC who had started first-line treatment with palbociclib between November 2017 and November 2019 were included.
Results
762 patients received Palbociclib in combination with AIs (69.4%) or fulvestrant (30.1%). Median age was 61.9 years (17.5% < 50 y; 51.8% 50-70 y; 30.7% > 70 y). 114 patients were premenopausal (15%). A total of 418 patients had visceral disease (54.9%). At baseline, patients with 1, 2-3 and >3 metastatic locations were 42.7%, 43% and 14.3% respectively. Results of real-world Response Rate (rwRR) and rwPFS are shown in the table. A total of 377 (49.5%) patients required a dose reduction. Among patients who had a first dose reduction, 164 (21.5%) required a second dose reduction. Median rwPFS was 28 months (CI 95% 25-33) in patients who had ≥ 1 dose reductions and 19 months (CI 95% 16-23) in patients who maintained the initial dose (HR 0.71; CI 95% 0.58-0.85, p=0.003).
Table: 234P
| rwRR | rwPFS | ||||
| CR | PR | SD | PD | ||
| N (%) | N (%) | N ( %) | N ( %) | Months CI 95% | |
| Age | |||||
| <50 | 15 (11.3) | 50 (37.6) | 46 (34.6) | 19 (14.3) | 27 (21-35) |
| 50-70 | 22 (5.6) | 145 (36.7) | 152 (38.5) | 57 (14.4) | 21 (19-26) |
| >70 | 13 (5.6) | 87 (37.2) | 88 (37.6) | 31 (13.2) | 27 (22-37) |
| Menopausal status | |||||
| Premenopausal | 13 (11.4) | 44 (38.6) | 40 (35.1) | 15 (13.2) | 27 (20-35) |
| Postmenopausal | 37 (5.7) | 238 (36.3) | 246 (38) | 92 (14.2) | 24 (21-27) |
| Visceral metastasis | |||||
| Yes | 21 (7.4) | 17 (41.4) | 141 (33.7) | 63 (15.1) | 20 (18-23) |
| No | 29 (8.4) | 109 (31.7) | 145 (42.2) | 44 (12.8) | 30 (25-36) |
| Nº of locations | |||||
| 1 | 24 (7.4) | 100 (30.8) | 136 (41.8) | 46 (14.2) | 34 (28-39) |
| 2-3 | 23 (7.0) | 132 (40.2) | 116 (35.4) | 47 (14.3) | 20 (18.24) |
| >3 | 3 (2.8) | 50 (45.9) | 34 (31.2) | 14 (12.8) | 19 (14-24) |
CR, complete response; PR, partial response; SD, stable disease; PD, progressive disease; NA, not available; NR, not reached
Conclusions
Age at start of the treatment and menopausal status were not associated with PFS. Patients with visceral metastasis and >1 sites of metastasis had shorter PFS. The incidence of dose reductions was higher compared with PALOMA-2 & 3 trials. However, dose reductions did not affect Palbociclib efficacy.
Clinical trial identification
NCT04874025.
Legal entity responsible for the study
Department of Investigation and Clinical Trials of Hospital Clínico San Carlos (UICEC-IdISSC).
Funding
Pfizer.
Disclosure
F. Moreno Anton: Financial Interests, Personal, Advisory Board: Pfizer, Novartis, Daiichi Sankyo, AstraZeneca, Gilead, MSD, Roche, Seagen; Financial Interests, Institutional, Research Grant: Pfizer; Financial Interests, Personal, Invited Speaker: Pfizer, MSD; Financial Interests, Personal, Principal Investigator: Novartis. M. Bellet-Ezquerra: Financial Interests, Personal, Advisory Board: Pfizer, Novartis, Lilly, Stemline-Menarini; Financial Interests, Personal, Speaker’s Bureau: Pfizer, Novartis, Lilly. L.M. Manso Sanchez: Financial Interests, Personal, Advisory Board: Pfizer; Financial Interests, Personal, Other: Pfizer; Financial Interests, Personal, Invited Speaker: Pfizer. P. Tolosa Ortega: Financial Interests, Personal, Invited Speaker: Novartis, Pfizer, Lilly, Seagen, AstraZeneca, Daiichi Sankyo and MSD; Financial Interests, Personal, Advisory Board: Novartis, Adamed, Seagen and Daiichi Sankyo; Financial Interests, Personal, Full or part-time Employment, Medical Advisor and Madical Monitor: SOLTI. R. Andrés Conejero: Financial Interests, Personal, Invited Speaker: Pfizer; Financial Interests, Personal, Other: Pfizer. E. Galve-Calvo: Financial Interests, Personal, Invited Speaker: AstraZeneca, Daiichi Sankyo, Gilead, Pfizer; Financial Interests, Personal, Expert Testimony: AstraZeneca, Daiichi Sankyo, Eisai, Gilead, Novartis, Pfizer, Pierre Fabre, Roche; Financial Interests, Personal, Advisory Board: AstraZeneca, Daiichi Sankyo, Gilead, Pfizer; Financial Interests, Personal, Other: Roche. F. Ayala de la Pena: Financial Interests, Personal, Advisory Board: AstraZeneca, Celgene, Eisai, Novartis, Roche, Pfizer, Pierre Fabre, Lilly, Sanofi, Seagen, Daiichi Sankyo; Financial Interests, Personal, Sponsor/Funding: Roche, Celgene, MSD; Financial Interests, Personal, Other: Roche, Pfizer, Pierre Fabre, MSD. S. Lopez-Tarruella Cobo: Financial Interests, Personal, Advisory Board: AstraZeneca, Daiichi Sankyo, Pfizer, Novartis, Lilly, Gilead, GSK, Roche, Pierre Fabre, Seagen, Menarini_Stemline, Gebro Pharma; Non-Financial Interests, Invited Speaker: GEICAM, SEOM. B.A. Hernando Fernandez: Financial Interests, Personal, Advisory Board: Seagen, Lilly, GSK, PharmaMar, Pfizer, Tesaro; Financial Interests, Personal, Other: Pierre Fabre. N. Martinez Jañez: Financial Interests, Personal, Advisory Board: Roche, Daiichi Sankyo, AstraZeneca, Pfizer, Eisai. All other authors have declared no conflicts of interest.