Translational and real-world evidence of trastuzumab biosimilar CT-P6 plus pertuzumab in neoadjuvant HER2-positive early breast cancer

Background Data on neoadjuvant treatment with trastuzumab biosimilars, particularly CT-P6, in combination with pertuzumab, are limited. This study evaluates the efficacy, tolerability, and immunogenicity of CT-P6 plus pertuzumab and chemotherapy, in routine clinical practice for HER2-positive early...

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Detalles Bibliográficos
Autores: Alonso Romero, José Luis, Martínez García, Jerónimo, Carrillo Vicente, Raúl, Fernández Aramburo, Antonio, Ferrando Díez, Angélica, Sánchez Henarejos, Pilar, de la Morena Barrio, Pilar, Puertes Boix, Ana, Jiménez, María Dolores, Peña Siles, Joaquín, Parejo Maestre, José Antonio, de las Heras Rubio, Antonio, Ruiz Carreño, Paula
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2026
País:España
Institución:Universidad de Sevilla (US)
Repositorio:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:dnet:idus________::52d38c193b9d8c56df3d1c0952a6ab49
Acceso en línea:https://hdl.handle.net/11441/186521
https://doi.org/10.1007/s10549-026-07895-8
Access Level:acceso abierto
Palabra clave:HER2-positive early breast cancer
Neoadjuvant treatment
Routine clinical practice
Trastuzumab biosimilar. Trastuzumab CT-P6
Descripción
Sumario:Background Data on neoadjuvant treatment with trastuzumab biosimilars, particularly CT-P6, in combination with pertuzumab, are limited. This study evaluates the efficacy, tolerability, and immunogenicity of CT-P6 plus pertuzumab and chemotherapy, in routine clinical practice for HER2-positive early breast cancer, including translational biomarker analyses related to pathologic complete response (pCR). Methods Prospective, multicenter, observational study in 102 patients with HER2-positive early breast cancer. Patients received hospital-preferred neoadjuvant regimens protocols, with (scheme 1 and 3) or without anthracyclines (scheme 2). The primary endpoint was pCR, defined as the absence of invasive tumor in both the breast and axillary lymph nodes (ypT0/ypTis and ypN0). Translational endpoints included soluble HER2, anti-trastuzumab CT-P6 antibodies, and exploratory response-related modeling approaches supported by machine learning techniques. Results Among patients who underwent surgery, pCR (ypT0/ypTis and ypN0) was achieved in 57.43% of cases, with no significant differences between anthracycline-based and non anthracycline-based regimens. Soluble HER2 and antitrastuzumab CT-P6 antibodies were not significantly associated with pCR. Treatment was well-tolerated; the most relevant Grade 3–4 treatment-related adverse events were diarrhea (2.25%) and asthenia (0.50%). No immunogenicity or clinically relevant cardiotoxicity was observed. Conclusions Trastuzumab CT-P6 combined with pertuzumab and chemotherapy can be used in neoadjuvant treatment for HER2-positive early breast cancer, showing pCR rates comparable to the reference trastuzumab and without evidence of immunogenicity. Exploratory analyses of soluble HER2 and anti-trastuzumab CT-P6 antibodies did not demonstrate a significant association with pCR, although this possibility cannot be excluded. Their assessment contributes to the translational understanding of biosimilar integration into curative regimens.