Martínez-Jáñez, NoeliaBellet, MeritxellManso Sánchez, Luis ManuelHenao Carrasco, FernandoAntón, AntonioMorales, SerafínTolosa Ortega, PabloObadia Gil, Verónica LuisaSampedro, TeresaAndrés, RaquelCalvo Martínez, LourdesGalve Calvo, ElenaLópez, RafaelAyala de la Peña, FranciscoLópez Tarruella, SaraHernando Fernandez de Aranguiz, Blanca AscensiónBoronat Ruiz, LaiaMartos Cardenas, TamaraChacón, José IgnacioMoreno Antón, Fernando2025-03-072025-03-072024Martínez-Jañez N, Ezquerra MB, Manso Sanchez LM, Carrasco FH, Torres AA, Morales S, et al. First-line therapy with palbociclib in patients with advanced HR+/HER2- breast cancer: The real-life study PALBOSPAIN. Breast Cancer Res Treat. 2024 Jul;206(2):317-28. DOI: 10.1007/s10549-024-07287-w0167-6806http://hdl.handle.net/10230/69849Purpose: To evaluate the efficacy and safety of first-line therapy with palbociclib in a Spanish cohort treated after palbociclib approval. Methods: PALBOSPAIN is an observational, retrospective, multicenter study evaluating real-world patterns and outcomes with 1 L palbociclib in men and women (any menopausal status) with advanced HR+/HER2- BC diagnosed between November 2017 and November 2019. The primary endpoint was real-world progression-free survival (rw-PFS). Secondary endpoints included overall survival (OS), the real-world response rate (rw-RR), the clinical benefit rate, palbociclib dose reduction, and safety. Results: A total of 762 patients were included. The median rw-PFS and OS were 24 months (95% CI 21-27) and 42 months (40-not estimable [NE]) in the whole population, respectively. By cohort, the median rw-PFS and OS were as follows: 28 (95% CI 23-39) and 44 (95% CI 38-NE) months in patients with de novo metastatic disease, 13 (95% CI 11-17) and 36 months (95% CI 31-41) in patients who experienced relapse < 12 months after the end of ET, and 31 months (95% CI 26-37) and not reached (NR) in patients who experienced relapse > 12 months after the end of ET. rw-PFS and OS were longer in patients with oligometastasis and only one metastatic site and those with non-visceral disease. The most frequent hematologic toxicity was neutropenia (72%; grade ≥ 3: 52.5%), and the most common non-hematologic adverse event was asthenia (38%). Conclusion: These findings, consistent with those from clinical trials, support use of palbociclib plus ET as 1 L for advanced BC in the real-world setting, including pre-menopausal women and men. Trial registration number: NCT04874025 (PALBOSPAIN). Date of registration: 04/30/2021 retrospectively registered.application/pdfeng© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.info:eu-repo/semantics/articlehttp://dx.doi.org/10.1007/s10549-024-07287-wAdvanced breast cancerFirst-line treatmentHR+/HER2−Overall survivalPalbociclibProgression-free survivalinfo:eu-repo/semantics/openAccess