RC0639: phase II study of paclitaxel, trastuzumab, and lapatinib as adjuvant therapy for early stage HER2-positive breast cancer

Overview of New Treatments with Immunotherapy for Breast Cancer and a Proposal of a Combination Therapy

According to data from the U.S. National Cancer Institute, cancer is one of the leading causes of death worldwide with approximately 14 million new cases and 8.2 million cancer-related deaths in 2018. More than 60% of the new annual cases in the world occur in Africa, Asia, Central America, and South America, with 70% of cancer deaths in these regions. Breast cancer is the most common cancer in women, with 266,120 new cases in American women and an estimated 40,920 deaths for 2018. Approximately one in six women diagnosed with breast cancer will die in the coming years. Recently, novel therapeutic strategies have been implemented in the fight against breast cancer, including molecules able to block signaling pathways, an inhibitor of poly [ADP-ribose] polymerase (PARP), growth receptor blocker antibodies, or those that reactivate the immune system by inhibiting the activities of inhibitory receptors like cytotoxic T-lymphocyte antigen 4 (CTLA-4) and programmed death protein 1 (PD-1). However, novel targets include reactivating the Th1 immune response, changing tumor microenvironment, and co-activation of other components of the immune response such as natural killer cells and CD8+ T cells among others. In this article, we review advances in the treatment of breast cancer focused essentially on immunomodulatory drugs in targeted cancer therapy. Based on this knowledge, we formulate a proposal for the implementation of combined therapy using an extracorporeal immune response reactivation model and cytokines plus modulating antibodies for co-activation of the Th1- and natural killer cell (NK)-dependent immune response, either in situ or through autologous cell therapy. The implementation of "combination immunotherapy" is new hope in breast cancer treatment. Therefore, we consider the coordinated activation of each cell of the immune response that would probably produce better outcomes. Although more research is required, the results recently achieved by combination therapy suggest that for most, if not all, cancer patients, this tailored therapy may become a realistic approach in the near future.

N083E (Alliance): long-term outcomes of patients treated in a pilot phase II study of docetaxel, carboplatin, trastuzumab, and lapatinib as adjuvant therapy for early-stage HER2-positive breast cancer

BACKGROUND

The addition of lapatinib (L) to trastuzumab (T) was previously found to be synergistic in preclinical models and in the neoadjuvant setting. Prior to the results of the ALTTO trial, this study assessed the safety and feasibility of adding L to the standard adjuvant docetaxel, carboplatin, and trastuzumab (TCH) regimen in early-stage HER2-positive breast cancer (HER2+ BC).

METHODS

In this single-arm, 2-stage, phase II study, patients with stages I-III HER2+ BC received TCH plus L at 1000 mg daily for a total of 12 months. The primary endpoint was the safety and tolerability, including the rate of diarrhea. Secondary endpoints included adverse event (AE) profile using the NCI CTCAE v3.0 and cardiac safety.

RESULTS

Thirty eligible patients were enrolled. Median follow-up is 5.3 years. Diarrhea was the most common AE with 50% Grade (G)1/2 and 43% G3 diarrhea. However, it was responsive to dose reduction of L (750 mg) and institution of anti-diarrheal medications. Cardiovascular AE were infrequent and no patients experienced congestive heart failure while on treatment.

CONCLUSION

TCHL was a tolerable regimen at a starting L dose of 750 mg PO daily when given concurrently with chemotherapy.

Practical consensus recommendations regarding the management of HER2 neu positive early breast cancer

Over-expression of HER2 is generally considered to be a negative prognostic feature because it accompanies an increase in breast cancer mortality. However, the development of agents that specifically target HER2 has improved the management of patients with these tumours. This expert group used data from published literature, practical experience and opinion of a large group of academic oncologists to arrive at these practical consensus recommendations with regards to the use of these agents and the management of HER2 neu early breast cancer for the benefit of community oncologists.

Exploitation of Gene Expression and Cancer Biomarkers in Paving the Path to Era of Personalized Medicine

Cancer therapy agents have been used extensively as cytotoxic drugs against tissue or organ of a specific type of cancer. With the better understanding of molecular mechanisms underlying carcinogenesis and cellular events during cancer progression and metastasis, it is now possible to use targeted therapy for these molecular events. Targeted therapy is able to identify cancer patients with dissimilar genetic defects at cellular level for the same cancer type and consequently requires individualized approach for treatment. Cancer therapy begins to shift steadily from the traditional approach of “one regimen for all patients” to a more individualized approach, through which each patient will be treated specifically according to their specific genetic defects. Personalized medicine accordingly requires identification of indicators or markers that guide in the decision making of such therapy to the chosen patients for more effective therapy. Cancer biomarkers are frequently used in clinical practice for diagnosis and prognosis, as well as identification of responsive patients and prediction of treatment response of cancer patient. The rapid breakthrough and development of microarray and sequencing technologies is probably the main tool for paving the way toward “individualized biomarker-driven cancer therapy” or “personalized medicine”. In this review, we aim to provide an updated knowledge and overview of the current landscape of cancer biomarkers and their role in personalized medicine, emphasizing the impact of genomics on the implementation of new potential targeted therapies and development of novel cancer biomarkers in improving the outcome of cancer therapy.

Evaluation of Left Ventricular Ejection Fractions in Breast Cancer Patients Undergoing Long-Term Trastuzumab Treatment

Background

The aim of this study was to assess the long-term clinical tolerance and cardiac safety during trastuzumab treatment for patients diagnosed as having breast cancer with human epidermal growth factor receptor 2 (HER2) overexpression.

Material/Methods

A total 105 female cases diagnosed as having breast cancer with high expression of Her2, were treated with trastuzumab (T). All of them underwent electrocardiography monitoring in the process of T treatment. Left ventricular ejection fractions (LVEFs) were estimated using echocardiography before the T treatment and every 3 months. General clinical data and above parameters were collected and reviewed as analysis.

Results

The mean value of LVEFs with baseline was higher than those at other time points. All LVEFs were more than 50% during the course of trastuzumab treatment. The decline scope ≥15% of LVEFs ranged from 2 months to 16 months, and the ratios were counted for 3.1% at 2 months, 4.3% at 6 months, 3.8% at 10 months, and 5.4% at 16 months. Furthermore, a larger decrease of LVEF during the course occurred mainly in the patients with cumulative dose of A >300 mg/m², without CPD and 16-month duration of T treatment. There was a strong correlation between cumulative dose of A, cyto/cardio-protection drugs (CPD), duration of T, and the change of LVEF (P=0.82, P=0.744, and P=0.717, respectively), which indicated that 3 factors may be associated with the change in LVEF (P<0.05).

Conclusions

The LVEF in patients with trastuzumab treatment was significantly decreased, which may be seen as a favorable benefit-risk ratio for patients undergoing long-term trastuzumab treatment.

Trastuzumab cardiotoxicity: from clinical trials to experimental studies

Epidermal growth factor receptor-2 (HER-2) is overexpressed in 20 to 25% of human breast cancers, which is associated with aggressive tumour growth and poor prognosis. Trastuzumab (Herceptin®) is a humanized monoclonal antibody directed against HER-2, the first highly selective form of therapy targeting HER-2 overexpressing tumours. Although initial trials indicated high efficacy and a favourable safety profile of the drug, the first large, randomized trial prompted a retrospective analysis of cardiac dysfunction in earlier trials utilizing trastuzumab. There has been ongoing debate on the cardiac safety of trastuzumab ever since, initiating numerous clinical and preclinical investigations to better understand the background of trastuzumab cardiotoxicity and evaluate its effects on patient morbidity. Here, we have given a comprehensive overview of our current knowledge on the cardiotoxicity of trastuzumab, primarily focusing on data from clinical trials and highlighting the main molecular mechanisms proposed.

LINKED ARTICLES

This article is part of a themed section on New Insights into Cardiotoxicity Caused by Chemotherapeutic Agents. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.21/issuetoc.

The efficiency and safety of trastuzumab and lapatinib added to neoadjuvant chemotherapy in Her2-positive breast cancer patients: a randomized meta-analysis

Background

The addition of human epidermal growth factor receptor 2 (Her2) therapies to neoadjuvant chemotherapy (NAC) during treatment of Her2-positive breast cancer has been proposed as an effective way to improve the prognosis. However, the treatment outcomes of adding trastuzumab, lapatinib, or both to NAC were not unequivocal in randomized clinical trials. Based on these data, a meta-analysis was performed.

Objective

The main objective was to evaluate the efficiency and safety of trastuzumab and lapatinib added to NAC for treatment of Her2-positive breast cancer.

Methods

ClinicalTrials.gov and PubMed were searched for randomized clinical trials that compared trastuzumab, lapatinib, or both, added to NAC. The main endpoint was a pathologically complete response (pCR) rate, in breast only or in breast and lymph nodes. The drug safety and the influence of hormone-receptor status, comparing the clinical response and the rate of breast conservation, were evaluated.

Results

A total of eight publications were included in the primary analysis, designed as two or three subgroups. The cumulative cases were 2,349 and the analyses of all the clinical trials showed that the pCR rate was significantly higher in the group receiving trastuzumab than that in the group with lapatinib, either in breast only (P=0.001) or in breast and lymph nodes (P=0.0001). Similar results could be seen in comparisons of the combination versus trastuzumab group. Further studies of subgroups divided into hormone receptor-positive or-negative patients showed that the addition of trastuzumab or dual Her2-targeted therapy significantly improved the pCR rate in patients who were hormone-insensitive. Regarding the toxic effects, we found more grade 3 and 4 toxic effects, such as diarrhea, skin disorder, and hepatic biochemical changes in the lapatinib and combination groups. No temporally significant differences were found when the clinical response and the rate of breast conservation in the groups were analyzed.

Conclusion

The combination of trastuzumab and lapatinib was superior to single-agent treatment for improved pCR rate. However, combination treatment was not effective in improving the rate of breast conservation. Furthermore, a higher risk for toxicity was associated with combined administration.

Dual HER2 blockade in the neoadjuvant and adjuvant treatment of HER2-positive breast cancer

Human epidermal growth factor receptor 2 (HER2) is a tyrosine kinase transmembrane receptor that is overexpressed on the surface of 15%–20% of breast tumors and has been associated with poor prognosis. Consistently improved pathologic response and survival rates have been demonstrated with use of trastuzumab in combination with standard chemotherapy in both early and advanced breast cancer. However, resistance to trastuzumab may pose a major problem in the effective treatment of HER2-positive breast cancer. Dual HER2 blockade, using agents that work in a complimentary fashion to trastuzumab, has more recently been explored to evade resistance in both the preoperative (neoadjuvant) and adjuvant settings. Increased effectiveness of dual anti-HER2 agents over single blockade has been recently reported in clinical studies. Pertuzumab in combination with trastuzumab and taxane is currently approved in the metastatic and neoadjuvant treatment of HER2-positive breast cancer. Various biomarkers have also been investigated to identify subsets of patients with HER2-positive tumors who would likely respond best to these targeted therapy combinations. In this article, available trial data regarding efficacy and toxicity of treatment with combination HER2 agents in the neoadjuvant and adjuvant setting have been reviewed, and relevant correlative biomarker data from these trials have been discussed.

Efficacy and mechanism of action of the tyrosine kinase inhibitors gefitinib, lapatinib and neratinib in the treatment of HER2-positive breast cancer: preclinical and clinical evidence

An increasing number of tumors, including breast cancer, overexpress proteins of the epidermal growth factor receptor (EGFR) family. The interaction between family members activates signaling pathways that promote tumor progression and resistance to treatment. Human epidermal growth factor receptor type II (HER2) positive breast cancer represents a clinical challenge for current therapy. It has motivated the development of novel and more effective therapeutic EGFR family target drugs, such as tyrosine kinase inhibitors (TKIs). This review focuses on the effects of three TKIs mostly studied in HER2- positive breast cancer, lapatinib, gefitinib and neratinib. Herein, we discuss the mechanism of action, therapeutic advantages and clinical applications of these TKIs. To date, TKIs seem to be promising therapeutic agents for the treatment of HER2-overexpressing breast tumors, either as monotherapy or combined with other pharmacological agents.

Exploring mechanisms of acquired resistance to HER2 (human epidermal growth factor receptor 2)-targeted therapies in breast cancer

HER2 (human epidermal growth factor receptor 2)-targeted therapy in breast cancer is one of the earliest and arguably most successful examples of the modern class of targeted drugs. Initially identified in the 1980s, the observation that HER2 acts as an independent predictor of poor prognosis in the 20% of breast cancer cases carrying a gene amplification or protein overexpression cemented its place at the forefront of research in this field. The outlook for patients with HER2-positive breast cancer has been revolutionized by the introduction of HER2-targeted agents, such as trastuzumab and lapatinib, yet resistance is frequently encountered and multiple different resistance mechanisms have been identified. We have explored resistance to a novel pan-HER inhibitor, AZD8931, and we examine mechanisms of resistance common to trastuzumab, lapatinib and AZD8931, and discuss the current problems associated with translating the wealth of pre-clinical data into clinical benefit.

[Towards an integrated approach to cardiovascular toxicities related to the treatments of breast cancer]

There is an increasing number of therapeutic options in breast cancer management. While prognosis improves, the cardiac toxicity related to treatments remains a significant issue. This toxicity has several clinical presentations and can be explained by complex and diverse molecular mechanisms. Systemic treatments (anthracyclines, inhibitors of HER2 signaling pathway, hormone therapy, antiangiogenic agents) and radiotherapy have their own cardiac toxicity. However, the toxicities associated with these treatments may potentiate together and the existence of pre-existing cardiovascular risk factors should be taken into account. The assessment of cardiac hazard evolves toward a multifactorial approach. Several possibilities exist to minimize the incidence of cardiac complications. Those include pharmacological and technological innovations, but also a more accurate selection of patients and a growing involvement of practitioners in the field of cardiac toxicity, which is prerequisite for an early management of cardiac events.

The design and discovery of water soluble 4-substituted-2,6-dimethylfuro[2,3-d]pyrimidines as multitargeted receptor tyrosine kinase inhibitors and microtubule targeting antitumor agents

The design, synthesis and biological evaluations of fourteen 4-substituted 2,6-dimethylfuro[2,3-d]pyrimidines are reported. Four compounds (11-13, 15) inhibit vascular endothelial growth factor receptor-2 (VEGFR-2), platelet-derived growth factor receptor β (PDGFR-β), and target tubulin leading to cytotoxicity. Compound 11 has nanomolar potency, comparable to sunitinib and semaxinib, against tumor cell lines overexpressing VEGFR-2 and PDGFR-β. Further, 11 binds at the colchicine site on tubulin, depolymerizes cellular microtubules and inhibits purified tubulin assembly and overcomes both βIII-tubulin and P-glycoprotein-mediated drug resistance, and initiates mitotic arrest leading to apoptosis. In vivo, its HCl salt, 21, reduced tumor size and vascularity in xenograft and allograft murine models and was superior to docetaxel and sunitinib, without overt toxicity. Thus 21 affords potential combination chemotherapy in a single agent.