Strategy and Status of Neoadjuvant Therapy for HER2-positive Breast Cancer / 肿瘤防治研究

Neoadjuvant therapy is a preoperative systemic treatment for patients with breast cancer. This therapy has greatly improved the clinical outcomes of human epidermal growth factor receptor 2 (HER2)-positive breast cancer, which is associated with poor prognosis. Currently, dual anti-HER2 antibodies, including trastuzumab and pertuzumab, combined with non-anthracycline chemotherapy is one of the standard regimens to achieve high pathologic complete response rate and satisfactory efficacy. The combination of trastuzumab with tyrosine kinase inhibitors, antibody-drug conjugate drugs, or immunotherapy combined with target therapy, under the indications of reasonable biomarkers, is effective for HER2-positive breast cancer. In this article, we briefly reviewed neoadjuvant therapy in the dual-targeting therapy era and discussed its future perspectives.

Cáncer de mama Her2-positivo: Terapias sistémicas actuales y experiencia local

El cáncer de mama (CM) es la primera causa de muerte por cáncer en mujeres tanto a nivel mundial como en Chile. Basados en características clínicas, histológicas y moleculares, múltiples estudios han identificado cuatro subtipos básicos de CM, los cuales están asociados a estrategias de tratamiento específicas y diferenciadas. El CM HER2-positivo representa un 15%-25% de todas las neoplasias mamarias y se caracteriza por su agresividad, recurrencia temprana y mayor tendencia a presentar compromiso del sistema nervioso central. En las últimas décadas, nuevas terapias dirigidas se han posicionado como el estándar de tratamiento y han cambiado la historia natural de esta enfermedad, transformándola en una enfermedad potencialmente curable incluso en etapas avanzadas. Esta revisión busca entregar un resumen de las bases biológicas de esta enfermedad. Por otro lado, dada la aparición de un creciente número de nuevas estrategias de manejo sistémico, nos proponemos revisar sus mecanismos de acción analizando reportes de datos clínicos publicados y la experiencia de nuestro grupo.

Breast cancer (BC) is the leading cause of cancer death for women both worldwide and in Chile. Based on clinical, histological, and molecular features, studies have identified four BC subtypes that correlate with treatment sensitivity. Human Epidermal growth factor Receptor type 2-positive (HER2+) BC represents 15%-25% of newly diagnosed breast neoplasms; HER2+ BC is characterized by its aggressive behavior, early recurrence, and higher risk of brain metastasis. In recent years, HER2-targeted therapies have become the mainstay of treatment and have redefined the natural history of this subtype, reducing relapse rates for early-stage patients and increasing survival in advanced-stage patients. Herein we review novel treatment strategies and their mechanisms of action, along with clinical and real-world data. We also provide a summary of currently available treatments for this subtype and our local experience regarding the management of this disease.

Using the analytic hierarchy process to elicit patient preference in the evaluation of first-line treatment of HER2-overexpressing metastatic breast cancer / Uso do processo analítico hierárquico para eleger a preferência do paciente na avaliação da primeira linha de tratamento do câncer de mama metastático her2 hiperexpresso

Abstract Background The many combinations of chemotherapeutic agents and biologicals available in the Brazilian National Health System for the treatment of metastatic breast cancer require analysis that contribute to decision making. Objective The study's primary aim was to evaluate the first-line treatment of HER2- overexpressing metastatic breast cancer from the Brazilian Unified Health System perspective using multicriteria decision analysis (MCDA). Method The treatment options evaluated were (a) pertuzumab combined with trastuzumab and docetaxel, and (b) trastuzumab in combination with docetaxel. Using the hierarchical analytical method, medical oncologists compared the relevance of five predefined criteria: overall survival, response to treatment, adverse events, cost- effectiveness, and budget impact. Results The therapeutic scheme considered more appropriate by the model was pertuzumab combined with trastuzumab and docetaxel. The most sensitive criteria were adverse events, cost-effectiveness, and budget impact. The results suggest that the classification has a close relationship with the perspective of healthcare professionals participating in the questionnaire. Conclusion Defining the treatment of an incurable disease associated with a short survival time and high-cost treatment options necessitates complex decision-making. MCDA allows the weighting of criteria and considering criteria that would be difficult to measure in other methods, such as cost-effectiveness. These aspects differ from economic models and contribute to a broader evaluation of health decision-making.

Resumo Introdução As diversas combinações de agentes quimioterápicos e biológicos disponíveis no Sistema Único de Saúde brasileiro para o tratamento do câncer de mama metastático requerem análises que contribuam para a tomada de decisões. Objetivo O objetivo principal deste estudo foi avaliar o tratamento de primeira linha para câncer de mama metastático HER2 hiperexpresso sob a perspectiva do Sistema Único de Saúde, utilizando a análise de decisão multicritérios (MCDA). Método As opções de tratamento avaliadas foram: (a) pertuzumabe em combinação com trastuzumabe e docetaxel, e (b) trastuzumabe em combinação com docetaxel. Usando o método analítico hierárquico, médicos oncologistas compararam a relevância dos cinco critérios predefinidos: sobrevida global, resposta ao tratamento, eventos adversos, custo-efetividade e impacto orçamentário. Resultados O esquema terapêutico considerado mais apropriado pelo modelo foi pertuzumabe em combinação com trastuzumabe e docetaxel. Os critérios mais sensíveis foram eventos adversos, custo-efetividade e impacto orçamentário. Os resultados sugerem que a classificação está associada à perspectiva do profissional de saúde participante do questionário. Conclusão Definir o tratamento de uma doença incurável associada a um tempo de sobrevida curto e opções de tratamento de alto custo requer uma tomada de decisão complexa. O MCDA permite ponderar e considerar critérios que seriam difíceis de medir em outros modelos de decisão. Esses aspectos contribuem para uma avaliação mais ampla da tomada de decisões em saúde.

Real-world Research of Trastuzumab and Pertuzumab Combined with Chemotherapy in Neoadjuvant Treatment of HER2-positive Breast Cancer / 肿瘤防治研究

Objective To analyze the efficacy and safety of trastuzumab (H) and pertuzumab (P) combined with different chemotherapy regiments in neoadjuvant therapy for HER2-positive breast cancer. Methods We retrospectively analyzed the clinical data of the patients with HER2-positive breast cancer who received HP combined with chemotherapy as neoadjuvant therapy and completed surgery. The primary endpoint was total pathologic complete response (tpCR) (ypT0/isypN0), the secondary endpoints were breast pathologic complete response(bpCR) (ypT0/is) and axillary pathologic complete response (apCR) (ypN0), and the factors influencing pCR were analyzed. Results A total of 63 patients were included, of whom 23 were treated with TCbHP, 27 were treated with THP regimen, and 13 were treated with AC-THP. The overall tpCR rate was 65.1%, of which TCbHP was 73.9%, THP was 55.6%, and AC-THP was 69.2%. The tpCR rate of HR-negative patients was 79.2%, higher than that of HR-positive 56.4%. The overall bpCR rate was 69.8%, and apCR rate was 81.0%. Univariate analysis showed that HER2 status was a related factor affecting tpCR (P=0.023). The total effective rate by MRI was 87.3%. The level 3 and 4 toxicity of the TCbHP regimen was slightly higher than those of the THP and the AC-THP regimens. Conclusion HP combined with chemotherapy have achieved relatively high pCR. HER2 status is a related factor that affects tpCR. The adverse reactions are controllable.

Personalizing pertuzumab and trastuzumab dosing regimens for adjuvant treatment of HER2-positive breast cancer / 中国临床药理学与治疗学

AIM: To design and implement personalized dosing regimens of trastuzumab and pertuzumab for an Asian patient with early breast cancer. METHODS: Trastuzumab and pertuzumab are important therapeutics for patients with HER2-positive breast cancer. Despite the similar pharmacokinetics (PK), their recommended dosing regimens differ: pertuzumab dosing is fixed whereas trastuzumab dosing depends on body weight; the dosing frequency is once every three weeks for pertuzumab but includes both once every week (QW) and once every three weeks (Q3W) for trastuzumab. A practicing physician has limited choices for dosing regimens when using the drugs in combination with chemotherapies. Besides convenience in drug administration, efficacy and safety as responses to the drug must be examined as part of studying dose-exposure-response relationship, which is the basis for deciding a dosing regimen. To understand the dose-exposure-response relationship of an individual patient, we reviewed literature on population PK analyses. The associated PK-covariate relationships including influential covariates such as disease status and demographics (e.g., body weight) that informed the patient's underlying dose-exposure-response relationships. Safety and efficacy factors essential for choosing appropriate dosing regimens were also considered - minimal target concentrations, higher adverse event rates in Asian patients, as well as administration convenience. RESULTS:Based on a thorough review of population PK and PK-covariate relationships of pertuzumab and trastuzumab, an individualized dosing regimen of once every two weeks (Q2W) was selected as the treatment option and implemented for this patient. CONCLUSION: The design of an individualized dosing regimen requires the knowledge of individualized dose-exposure-response relationships, and population analysis is an ideal tool for understanding the individualized dose-exposure-response relationships.

Anti-HER2 Antibodies In Combination With Chemotherapy Or Chemotherapy-Free Regimens Targeting Her2-Positive Breast Cancer: A Systematic Review

@#Breast cancer is the leading cause of cancer-related death in female worldwide. Human epidermal growth factor receptor 2 (HER2) amplification is observed in approximately 20% of breast cancer cases and is associated with poor clinical outcomes. Dual HER2 blockade without chemotherapy represents an attractive therapeutic approach, and it remains unresolved if anti-HER2 therapeutic antibodies are sufficient to replace chemotherapy regimens. In this review, we discuss the approved therapeutic monoclonal antibodies (pertuzumab and trastuzumab) and antibody-drug conjugate (trastuzumab emtansine or T-DM1) for the treatment of HER2-positive breast cancer patients. In summary, phase II and III clinical trials have demonstrated that dual HER2 blockade (pertuzumab and trastuzumab) plus chemotherapy regimens confer better efficacy compared with dual HER2 blockade alone, or anti-HER2 antibody monotherapy, in HER2-positive breast cancer patients. Dual HER2 blockade (pertuzumab and trastuzumab) combined with chemotherapies (5-fluorouracil, epirubicin, cyclophosphamide and docetaxel) yield superior response. Moreover, dual HER2 blockade (T-DM1 and pertuzumab) in combination with docetaxel represents a promising treatment regimen containing T-DM1. Ongoing clinical trials are assessing the optimal chemotherapy of choice with anti-HER2 antibodies combinations. In conclusion, improved outcomes are attributable to selection for the optimal chemotherapy regimen in combination with anti-HER2 antibodies instead of replacing chemotherapy altogether with the current line of anti-HER2 therapeutic antibodies.

Pertuzumab, primer inhibidor de la dimerización HER / Pertuzumab, first HER dimerization inhibitor

Entre un 15 y un 20% de pacientes con cáncer de mama presentan amplificación o sobre expresión de HER2, lo que le confiere un comportamiento más agresivo. Pese a que el advenimiento del trastuzumab, primer agente dirigido contra HER2, mejoró significativamente el pronóstico de este grupo de pacientes, el 50% de ellas aún progresa dentro del año de tratamiento. Pertuzumab, el primer inhibidor de la dimerización de HER2, muestra un mecanismo de acción complementario a trastuzumab, logrando mejores resultados clínicos en pacientes tratadas con ambos agentes anti-HER2 y quimioterapia. El presente trabajo repasa las propiedades de pertuzumab y su desarrollo clínico.

Approximately 15 to 20% of breast cancers present amplificationor overexpression of HER2, and these tumoursshow a more aggressive behavior. Trastuzumab, the firsttargeted agent against HER2, significantly improved prognosisfor these patients, but still around 50% shows diseaseprogression within the first year of treatment. Pertuzumab,the first HER2 dimerization inhibitor, has a mechanismof action that is complementary to that of trastuzumab,achieving enhanced efficacy for patients treated with bothanti-HER2 agents and chemotepapy. This work reviews themain aspects of pertuzumab and its clinical development.