Pooled analysis of diarrhea events in patients with cancer treated with lapatinib

Management and Mechanisms of Diarrhea Induced by Tyrosine Kinase Inhibitors in Human Epidermal Growth Factor Receptor-2-Positive Breast Cancer

Breast cancer has the highest incidence among female malignancies, significantly impacting women's health. Recently, numerous HER2-targeted therapies have achieved excellent clinical outcomes. Currently, anti-HER2 drugs are divided into three main categories: monoclonal antibodies, small-molecule tyrosine kinase inhibitors, and antibody-coupled drugs (ADCs). The main toxic side effects of small molecule TKI-based therapy are diarrhea, hand-foot syndrome, rash, nausea, and vomiting. Diarrhea is a potential predictor of tumor response, affecting up to 95% of cancer patients treated with TKIs. Severe gastrointestinal toxicity can result in the need for dose reductions and treatment interruptions. This not only compromises the efficacy of TKIs but also deteriorates human nutrition and quality of life. The majority of individuals develop diarrhea within 7 days of starting treatment, with approximately 30% developing grade 3 or higher diarrhea within 2-3 days of starting treatment. The severity of diarrhea typically correlates with the dosage of most TKIs. Current prevention and management strategies are primarily empirical, focusing on symptom alleviation rather than addressing the toxicological mechanisms underlying TKI-induced diarrhea. Consequently, anti-diarrheal drugs are often less effective in managing this condition in cancer patients receiving TKIs. Moreover, our understanding of the toxicological mechanisms responsible for such diarrhea remains limited, underscoring the urgent need to identify these mechanisms in order to develop effective anti-diarrheal medications tailored to this specific context. This review aims to elucidate management approaches and mechanisms for diarrhea induced by TKIs during HER2-positive breast cance.

Collagenous Colitis in a Patient With Gastric Cancer Who Underwent Chemotherapy

Herein, we present a case of collagenous colitis in a patient who underwent chemotherapy for gastric cancer, comprising five cycles of S-1 plus oxaliplatin and trastuzumab, followed by five cycles of paclitaxel and ramucirumab and seven cycles of nivolumab. The subsequent initiation of trastuzumab deruxtecan chemotherapy led to the development of grade 3 diarrhea after the second cycle of treatment. Collagenous colitis was diagnosed via colonoscopy and biopsy. The patient's diarrhea improved following the cessation of lansoprazole. This case highlights the importance of considering collagenous colitis as a differential diagnosis, in addition to chemotherapy-induced colitis and immune-related adverse event (irAE) colitis, in patients with similar clinical presentations.

Targeted Agents for HER2-Positive Breast Cancer: Optimal Use in Older Patients

The human epidermal growth factor-2 (HER2) gene is overexpressed in 15-20 % of all breast cancers. HER2 overexpression is a predictive factor in breast cancer and is associated with high rates of disease recurrence and death in the absence of adjuvant systemic therapy. With the advent of HER2-directed therapies, there has been a significant improvement in the outcome of HER2-positive (HER2+) breast cancer in all clinical settings. Patients aged > 65 years remain under-represented in most clinical trials. Existing literature suggests that older patients with HER2+ disease derive a similar benefit from anti-HER2 therapies as do their younger counterparts, in both adjuvant and metastatic settings. Cardiotoxicity from HER2-directed therapy is a major concern with older patients, especially in the setting of pre-existing co-morbidities. Older patients need a geriatric assessment before beginning any systemic therapy, to identify patients predisposed to developing toxicity and to plan therapy. Many onco-geriatric tools have been developed to further identify frail patients. In this article, we discuss the most up-to-date clinical data on existing therapies for HER2+ breast cancer in adjuvant, neoadjuvant, and metastatic settings, and their application in older patients. We attempt to highlight clinical benefits and toxicities in this group that may aid clinicians in therapeutic decision making.

The role of tyrosine kinase inhibitors in the treatment of HER2+ metastatic breast cancer

The introduction of trastuzumab and other subsequent human epidermal growth factor receptor 2 (HER2)-targeted therapies dramatically shifted the treatment landscape of HER2+ breast cancer, changing the natural history of the disease. There is no standard-of-care for patients with HER2+ metastatic breast cancer (MBC) in third and later lines of treatment; however, continued use of anti-HER2 therapies is recommended. Small-molecule tyrosine kinase inhibitors (TKIs) that target HER2 and other HER family receptors play a central role in this setting. TKIs have demonstrated various degrees of efficacy against central nervous system (CNS) metastases, which are a major clinical challenge for patients with HER2+ MBC. The TKIs lapatinib, neratinib, and tucatinib have received regulatory approval for the treatment of HER2+ MBC, while pyrotinib and afatinib have been evaluated in this setting. These TKIs vary by molecular weight, HER protein specificity and reversibility of binding and in turn have unique safety profiles. Toxicities reported in clinical trials of TKIs in HER2+ MBC that may require specific management strategies include diarrhoea, palmar-plantar erythrodysesthesia syndrome and rash. Here, we review the efficacy data, including CNS activity, and the safety profiles of the TKIs, and we provide guidance on adverse event management. Finally, we discuss how to incorporate the TKIs into the HER2+ MBC treatment algorithm.

Effects of tyrosine kinase inhibitors on thyroid function and thyroid hormone metabolism

The increasing knowledge of the molecular mechanisms in the cell signaling pathways of malignant cells, has recently led to the discovery of several tyrosine kinases (TKs), mainly TK receptors (TKR), which play a major role in the pathogenesis of many types of cancer. These receptors, physiologically involved in cell growth and angiogenesis, may harbor mutations or be overexpressed in malignant cells, and represent a target for anticancer therapy. Indeed, several therapeutic agents targeting specific altered pathways such as RET, BRAF, RAS, EGFR and VEGFR, have been identified. Tyrosine kinase inhibitors (TKIs) affect TK dependent oncogenic pathways by competing with ATP binding sites of the TK domain, thus blocking the activity of the enzyme, and thereby inhibiting the growth and spread of several cancers. Although the therapeutic action may be very effective, these molecules, due to their mechanism of multitargeted inhibition, may produce adverse events involving several biological systems. Both hypothyroidism and thyrotoxicosis have been reported during treatment with TKI, as well as an effect on the activity of enzymes involved in thyroid hormone metabolism. The pathogenic mechanisms leading to thyroid dysfunction and changes in serum thyroid function tests occurring in patients on TKI are reviewed and discussed in this manuscript.

The GLP-2 analogue elsiglutide reduces diarrhoea caused by the tyrosine kinase inhibitor lapatinib in rats

PURPOSE

Lapatinib is a small molecule tyrosine kinase inhibitor used to treat breast cancer, often in combination with chemotherapy. Diarrhoea commonly occurs in up to 78% of patients undertaking lapatinib treatment. The mechanism of this diarrhoea is currently unknown. Elsiglutide is a GLP-2 analogue known to increase cell proliferation and reduce apoptosis in the intestine.

METHODS

We used a previously developed rat model of lapatinib-induced diarrhoea to determine if co-treatment with elsiglutide was able to reduce diarrhoea caused by lapatinib. Additionally, we analysed the caecal microbiome of these rats to assess changes in the microbiome due to lapatinib.

RESULTS

Rats treated with lapatinib and elsiglutide had less severe diarrhoea than rats treated with lapatinib alone. Serum lapatinib levels, blood biochemistry, myeloperoxidase levels and serum limulus amebocyte lysate levels were not significantly different between groups. Rats treated with lapatinib alone had significantly higher histopathological damage in the ileum than vehicle controls. This increase was not seen in rats also receiving elsiglutide. Rats receiving lapatinib alone had lower microbial diversity than rats who also received elsiglutide.

CONCLUSIONS

Elsiglutide was able to reduce diarrhoea from lapatinib treatment. This does not appear to be via reduction in inflammation or barrier permeability, and may be due to thickening of mucosa, leading to increased surface area for fluid absorption in the distal small intestine. Microbial changes seen in this study require further research to fully elucidate their role in the development of diarrhoea.

Patterns of occurrence and implications of neratinib-associated diarrhea in patients with HER2-positive breast cancer: analyses from the randomized phase III ExteNET trial

Background

We characterized patterns of occurrence and the impact of neratinib-associated diarrhea in the absence of protocol-directed antidiarrheal prophylaxis or a formal diarrhea management plan using data from Extended Adjuvant Treatment of Breast Cancer with Neratinib (ExteNET).

Methods

ExteNET is a multicenter, double-blind, placebo-controlled, randomized phase III trial involving community-based and academic institutions in 40 countries. Women with HER2-positive early-stage breast cancer with prior standard primary therapy and trastuzumab-based (neo)adjuvant therapy were randomized to neratinib 240 mg/day or placebo for 12 months. Safety, a secondary outcome, was assessed using the National Cancer Institute Common Terminology Criteria version 3.0. Health-related quality of life by diarrhea grade was assessed using Functional Assessment of Cancer Therapy-Breast (FACT-B).

Results

Two thousand eight hundred sixteen women (1408 per group) were safety-evaluable. Grade 3 and 4 diarrhea occurred in 561 (39.8%) and 1 (0.1%) patients with neratinib versus 23 (1.6%) and 0 patients with placebo, respectively. In the neratinib group, 28.6% of patients had grade 3 events during month 1 decreasing to ≤ 6% after month 3. The median cumulative duration of grade 3/4 diarrhea with neratinib was 5 days (interquartile range, 2–9). Serious diarrheal events (n = 22, 1.6%) and diarrheal events requiring hospitalization (n = 20, 1.4%) were rare with neratinib. Changes in FACT-B total score by diarrhea grade in the neratinib group did not meet the threshold for clinically important differences.

Conclusions

In the absence of antidiarrheal prophylaxis, neratinib-related diarrhea is short-lived and not associated with complications or long-term sequelae. This suggests that targeted preventive management with antidiarrheal prophylaxis early during neratinib treatment is appropriate.

Trial registration

ClinicalTrials.gov NCT00878709. Registered 9 April 2009.

Electronic supplementary material

The online version of this article (10.1186/s13058-019-1112-5) contains supplementary material, which is available to authorized users.

Th1 cytokines sensitize HER-expressing breast cancer cells to lapatinib

The HER family of receptor tyrosine kinases has been linked to deregulation of growth and proliferation for multiple types of cancer. Members have therefore become thefocus of many drug and immune-based therapy innovations. The targeted anti-cancer agent, lapatinib, is a small molecule inhibitor that directly interferes with EGFR (HER-1)and HER-2 signaling, and indirectly reduces HER-3 signaling, thus suppressing important downstream events. A recently-developed dendritic cell-based vaccine against early breast cancer (ductal carcinoma in situ; DCIS) that generates strong Th1-dominated immunity against HER-2 has induced pathologic complete response in about one-third of immunized individuals. In vitro studies suggested cytokines secreted by Th1 cells could be major contributors to the vaccine effects including induction of apoptosis and suppression of HER expression. With a view toward improving complete response rates, we investigated whether the principle Th1 cytokines (IFN-γ and TNF-α) could act in concert with lapatinib to suppress activity of breast cancer lines in vitro. Lapatinib-sensitive SKBR3, MDA-MB-468 and BT474 cells were incubated with Th1 cytokines, lapatinib, or both. It was found that combined treatment maximized metabolic suppression(Alamar Blue assay), as well as cell death (Trypan Blue) and apoptosis(Annexin V/Propidium Iodide and TMRE staining). Combined drug plus cytokine treatment also maximized suppression of both total and phosphorylated forms of HER-2 and HER-3. Interestingly, when lapatinib resistant lines MDA-MB-453 and JIMT-1 were tested, it was found that the presence of Th1 cytokines appeared to enhance sensitivity for lapatinib-induced metabolic suppression and induction of apoptotic cell death, nearly abrogating drug resistance. These studies provide pre-clinical data suggesting the possibility that targeted drug therapy may be combined with vaccination to enhance anti-cancer effects, and furthermore that robust immunity in the form of secreted Th1 cytokines may have the capacity to mitigate resistance to targeted drugs.

Targeted agents for HER2-positive breast cancer in older adults: current and future perspectives

INTRODUCTION

One-third of breast cancer (BC) cases worldwide occur in women aged 65 years and older, with 10 to 15% overexpressing the human epidermal growth factor receptor 2 (HER2). Although several HER2-targeted therapies have been developed, the lack of data regarding their use in older patients hampers evidence-based decision-making for this population.

AREAS COVERED

We review current evidence on the efficacy and safety of HER2-targeted therapies in older adults with BC, focusing on approved therapies such as trastuzumab, lapatinib, pertuzumab, ado-trastuzumab-emtansine, and neratinib. Additionally, we discuss drugs under development to target the HER2-receptor, and to overcome resistance to existing therapies. Finally, we highlight the cardiotoxicity of HER2-targeted drugs among older adults.

EXPERT OPINION

Older adults are underrepresented in trials of HER2-targeted therapies in BC. We propose strategies to increase recruitment of older adults in clinical trials in order to increase the evidence base to treat this growing population.

Clinical pharmacology of oncology agents in older adults: A comprehensive review of how chronologic and functional age can influence treatment-related effects

Unique challenges exist when managing older adults with cancer. Associations between cancer and age-related physiologic changes have a direct impact on pharmacokinetics and pharmacodynamics of cancer therapies and can affect drug dosing, dose intensity, efficacy, safety and quality of life. The breadth and depth of these issues, however, have not been fully evaluated because the majority of clinical trials have focused on a younger and healthier population. As a consequence, little information is available to support clinicians in making evidence-based decisions regarding treatment with cancer therapies in older adults, especially those over age 75. Prior clinical pharmacology reviews summarized the literature on how age-related physiologic changes can influence and affect conventional and targeted anti-cancer treatments. Our article provides an updated review with expanded information that includes small molecule kinase inhibitors, monoclonal antibodies, immunotherapies, hormonal, conventional, and miscellaneous agents. Additionally, our article integrates how functional age, determined by the geriatric assessment (GA), can also influence treatment-related effects and health outcomes. Broadening cancer therapy trials to capture not only chronologic age but also functional age would allow clinicians to better identify subsets of older adults who benefit from treatment versus those most vulnerable to morbidity and/or mortality.

Lapatinib-Based Therapy in Heavily Pretreated HER2-Positive Metastatic Breast Cancer: A Single Institution Experience

Aims and Background

Lapatinib in combination with capecitabine is feasible in patients with HER2-positive metastatic breast cancer pretreated with anthracyclines, taxanes and trastuzumab, but inferior results were reported in the global lapatinib expanded access program in comparison with the phase III registration trial.

Methods and Study Design

Women with HER2-positive metastatic breast carcinoma after antracycline, taxane and trastuzumab-based regimens were treated at progression with lapatinib plus capecitabine. The outcome of these patients was evaluated. From April 2007 to August 2010, 68 patients were treated overall.

Results

Median progression-free survival was 6 months (range, 1–29), and median overall survival was 26 months (range, 1–39). Eight (12%; 95% CI, 4–25) patients experienced a complete response. Partial response was observed in 22 patients (31%; 95% CI, 20–42), for an overall response rate of 43% (95% CI, 31–55). The treatment with lapatinib plus capecitabine was well tolerated, with grade 3–4 toxicity reported in few patients, and no treatment-related deaths were noted. Of note, no cardiac toxicity was reported in this highly pretreated group of patients or in the subgroup of 10 elderly patients.

Conclusions

Our data confirm that lapatinib plus capecitabine is an active regimen even in heavily pretreated patients with visceral and brain metastases and is feasible and active also in selected elderly patients.

Phase I Study of ONT-380, a HER2 Inhibitor, in Patients with HER2+-Advanced Solid Tumors, with an Expansion Cohort in HER2+ Metastatic Breast Cancer (MBC)

Purpose: ONT-380 (ARRY-380) is a potent and selective oral HER2 inhibitor. This Phase I study determined the MTD, pharmacokinetics (PK) and antitumor activity of ONT-380 in HER2-positive advanced solid tumors, with an expansion cohort of patients with HER2⁺ MBC.Experimental Design: ONT-380 was administered twice daily (BID) in continuous 28-day cycles. After a modified 3+3 dose-escalation design determined the MTD, the expansion cohort was enrolled. PK properties of ONT-380 and a metabolite were determined. Response was evaluated by Response Evaluation Criteria in Solid Tumors (RECIST).Results: Fifty patients received ONT-380 (escalation = 33; expansion = 17); 43 patients had HER2⁺ MBC. Median prior anticancer regimens = 5. Dose-limiting toxicities of increased transaminases occurred at 800 mg BID, thus 600 mg BID was the MTD. Common AEs were usually Grade 1/2 in severity and included nausea (56%), diarrhea (52%), fatigue (50%), vomiting (40%) constipation, pain in extremity and cough (20% each). 5 patients (19%) treated at MTD had grade 3 AEs (increased transaminases, rash, night sweats, anemia, and hypokalemia). The half-life of ONT-380 was 5.38 hours and increases in exposure were approximately dose proportional. In evaluable HER2⁺ MBC (n = 22) treated at doses ≥ MTD, the response rate was 14% [all partial response (PR)] and the clinical benefit rate (PR + stable disease ≥ 24 weeks) was 27%.Conclusions: ONT-380 had a lower incidence and severity of diarrhea and rash than that typically associated with current dual HER2/EGFR inhibitors and showed notable antitumor activity in heavily pretreated HER2⁺ MBC patients, supporting its continued development. Clin Cancer Res; 23(14); 3529-36. ©2017 AACR.

Targeted Therapies in HER2-Overexpressing Metastatic Breast Cancer

Human epidermal growth factor receptor-2 (HER2) is amplified in 25-30% of breast cancers and is associated with aggressive disease and poorer survival. Multiple anti-HER2 targeted therapies have dramatically changed management and outcome of this subgroup, both in adjuvant and metastatic settings. Despite the improvement of survival thanks to trastuzumab, unclear mechanisms of resistance occur, which has led to the development of new anti-HER2 therapies such as lapatinib, pertuzumab, and trastuzumab emtansine (T-DM1). The optimal sequence of the available drugs is still not well established. All this progress raises the question of toxicity that need to be managed, especially with longer survival of patients. In this article, we review different anti-HER2 therapies used in HER2-positive m etastatic breast cancer.

New frontiers in mucositis

Mucositis is among the most debilitating side effects of radiotherapy, chemotherapy, and targeted anticancer therapy. Research continues to escalate regarding key issues such as etiopathology, incidence and severity across different mucosae, relationships between mucosal and nonmucosal toxicities, and risk factors. This approach is being translated into enhanced management strategies. Recent technology advances provide an important foundation for this continuum. For example, evolution of applied genomics is fostering development of new algorithms to rapidly screen genomewide single-nucleotide polymorphisms (SNPs) for patient-associated risk prediction. This modeling will permit individual tailoring of the most effective, least toxic treatment in the future. The evolution of novel cancer therapeutics is changing the mucositis toxicity profile. These agents can be associated with unique mechanisms of mucosal damage. Additional research is needed to optimally manage toxicity caused by agents such as mammalian target of rapamycin (mTOR) inhibitors and tyrosine kinase inhibitors, without reducing antitumor effect. There has similarly been heightened attention across the health professions regarding clinical practice guidelines for mucositis management in the years following the first published guidelines in 2004. New opportunities exist to more effectively interface this collective guideline portfolio by capitalizing upon novel technologies such as an Internet-based Wiki platform. Substantive progress thus continues across many domains associated with mucosal injury in oncology patients. In addition to enhancing oncology patient care, these advances are being integrated into high-impact educational and scientific venues including the National Cancer Institute Physician Data Query (PDQ) portfolio as well as a new Gordon Research Conference on mucosal health and disease scheduled for June 2013.

Effect of age on drug metabolism in women with breast cancer

INTRODUCTION

The aging of the population will increase the number of breast cancer patients requiring treatment in both the adjuvant and metastatic setting. Hormones, chemotherapy and targeted drugs all have a role in treatment. Older patients have been underrepresented in clinical trials making evidence-based decisions difficult. The increase in comorbidity and aging, polypharmacy and changes in function make pharmacotherapy decisions more complicated. Knowledge of the issues is critical in the prescribing of effective and safe therapy. There are factors associated with advancing age that can result in pharmacokinetic and pharmacodynamic variations in processing of hormonal agents, chemotherapy and targeted drugs.

AREAS COVERED

A review of the literature pertaining to pharmacokinetic changes in aging in breast cancer was untaken. Studies are reviewed involving single agents and some combinations.

EXPERT OPINION

Older patients should be considered for standard therapies. Their specific problems need to be evaluated by geriatric-specific assessment including functional status, end organ dysfunction and polypharmacy. There are few instances for age-related changes in pharmacokinetics and when present are usually not clinically significant. When changes are present, they are often the result of comorbidity, drug interactions and drug scheduling issues. The older patients may be more sensitive to certain toxicities such as cardiac toxicity, neuropathy and myelosuppression.

A Pilot Study of Dose-Dense Paclitaxel With Trastuzumab and Lapatinib for Node-negative HER2-Overexpressed Breast Cancer

BACKGROUND

Dual anti-HER2 therapy is effective for HER2-amplified breast cancer. Weekly paclitaxel, trastuzumab, and full-dose lapatinib (PTL) is not feasible because of grade 3 diarrhea. We conducted a phase II feasibility study of dose-dense (DD; every other week) PTL (ClinicalTrials.gov identifier, NCT01827163).

PATIENTS AND METHODS

Eligible patients had HER2-positive breast cancer, tumor size ≤ 3 cm, and negative nodes. Treatment included paclitaxel (175 mg/m(2) × 4, every 2 weeks with pegfilgrastim), trastuzumab (4 mg/kg load and then 2 mg/kg weekly), and lapatinib (1000 mg daily). After paclitaxel × 4, trastuzumab (6 mg/kg every 3 weeks) plus lapatinib were continued for 1 year. The primary endpoint was feasibility, defined as (1) > 80% of patients completing PTL without a dose delay or reduction, (2) grade 3 diarrhea rate < 20%, and (3) cardiac event rate < 4%.

RESULTS

From May 2013 to November 2013, we enrolled 20 of 55 planned patients. The median age was 49 years (range, 34-74 years). One patient had immediate paclitaxel hypersensitivity and was deemed inevaluable. Only 13 of 19 evaluable patients (68%) completed PTL without a dose delay or reduction or unacceptable toxicities. Only 3 of 19 (16%) had grade 3 diarrhea. Rash was frequent, with all grades in 18 of 19 (95%) and grade 3 in 2 of 19 (11%). The study was stopped early because of excess toxicity.

CONCLUSION

The discontinuation rate during DD PTL was high, owing, in part, to an unexpectedly high incidence of rash. The trial was halted, because the initial discontinuation rate from overall toxicity made it unlikely that full accrual would demonstrate feasibility.

Strategies for dealing with fraud in clinical trials

Research misconduct and fraud in clinical research is an increasing problem facing the scientific community. This problem is expected to increase due to discoveries in central statistical monitoring and with the increase in first-time clinical trial investigators in the increasingly global reach of oncology clinical trials. This paper explores the most common forms of fraud in clinical trials in order to develop offensive and defensive strategies to deal with fraud. The offensive strategies are used when fraud is detected during a trial and the defensive strategies are those design strategies that seek to minimize or eliminate the effect of fraud. This leads to a proposed fraud recovery plan (FRP) that would be specified before the start of a clinical trial and would indicate actions to be taken upon detecting fraud of different types. Statistical/regulatory issues related to fraud include: dropping all patients from a site that committed fraud, or just the fraudulent data (perhaps replacing the latter through imputation); the role of intent-to-treat analysis; effect on a planned interim analysis; effect on stratified analyses and model adjustment when fraud is detected in covariates; effect on trial-wide randomization, etc. The details of a typical defensive strategy are also presented. It is concluded that it is best to follow a defensive strategy and to have an FRP in place to follow if fraud is detected during the trial.

ErbB small molecule tyrosine kinase inhibitor (TKI) induced diarrhoea: Chloride secretion as a mechanistic hypothesis

Diarrhoea is a common, debilitating and potentially life threatening toxicity of many cancer therapies. While the mechanisms of diarrhoea induced by traditional chemotherapy have been the focus of much research, the mechanism(s) of diarrhoea induced by small molecule ErbB TKI, have received relatively little attention. Given the increasing use of small molecule ErbB TKIs, identifying this mechanism is key to optimal cancer care. This paper critically reviews the literature and forms a hypothesis that diarrhoea induced by small molecule ErbB TKIs is driven by intestinal chloride secretion based on the negative regulation of chloride secretion by ErbB receptors being disrupted by tyrosine kinase inhibition.

Neoadjuvant treatment with docetaxel plus lapatinib, trastuzumab, or both followed by an anthracycline-based chemotherapy in HER2-positive breast cancer: results of the randomised phase II EORTC 10054 study

BACKGROUND

Neoadjuvant trials conducted using a double HER2 blockade with lapatinib and trastuzumab, combined with different paclitaxel-containing chemotherapy regimens, have shown high pathological complete response (pCR) rates, but at the cost of important toxicity. We hypothesised that this toxicity might be due to a specific interaction between paclitaxel and lapatinib. This trial assesses the toxicity and activity of the combination of docetaxel with lapatinib and trastuzumab.

PATIENTS AND METHODS

Patients with stage IIA to IIIC HER2-positive breast cancer received six cycles of chemotherapy (three cycles of docetaxel followed by three cycles of fluorouracil, epirubicin, cyclophosphamide). They were randomised 1 : 1 : 1 to receive during the first three cycles either lapatinib (1000 mg orally daily), trastuzumab (4 mg/kg loading dose followed by 2 mg/kg weekly), or trastuzumab + lapatinib at the same dose. The primary end point was pCR rate defined as ypT0/is. Secondary end points included safety and toxicity. pCR rate defined as ypT0/is ypN0 was assessed as an exploratory analysis. In June 2012, arm A was closed for futility based on the results from other studies.

RESULTS

From October 2010 to January 2013, 128 patients were included in 14 centres. The percentage of the 122 assessable patients with pCR in the breast, and pCR in the breast and nodes, was numerically highest in the lapatinib + trastuzumab group (60% and 56%, respectively), intermediate in the trastuzumab group (52% and 52%), and lowest in the lapatinib group (46% and 36%). Frequency (%) of the most common grade 3-4 toxicities in the lapatinib /trastuzumab/lapatinib + trastuzumab arms were: febrile neutropenia 23/15/10, diarrhoea 9/2/18, infection (other) 9/4/8, and hepatic toxicity 0/2/8.

CONCLUSIONS

This study demonstrates a numerically modest pCR rate increase with double anti-HER2 blockade plus chemotherapy, but suggests that the use of docetaxel rather than paclitaxel may not reduce toxicity.

CLINICALTRIALSGOV

NCT00450892.

Targeted therapy in older patients with solid tumors

The introduction of targeted therapy has ushered in the era of personalized medicine in cancer therapy. The increased understanding of tumor heterogeneity has led to the determination of specific targets that can be exploited in treatment. This review highlights approved drugs in different therapeutic classes, including tyrosine kinase inhibitors, mammalian target of rapamycin inhibitors, drugs targeted to the human epidermal growth factor receptor 2, BRAF-mutation targeted drugs, anti-epidermal growth factor receptor inhibitors, and anti-vascular endothelial growth factor therapy. There have not been elderly patient-specific trials of these therapies. Most of the data are extrapolated from larger trials in which older patients generally were a fraction of the participants. Therapeutic recommendations are made on the basis of this analysis with the recognition that the older clinical trial participants may not be representative of patients seen in daily practice. Patient selection and geriatric evaluation are critical for appropriate drug selection, dosing, and monitoring. With care, these therapies are a major step forward in the safe and effective treatment of older patients with cancer.

Determining the mechanisms of lapatinib-induced diarrhoea using a rat model

INTRODUCTION

Diarrhoea caused by treatment with receptor tyrosine kinase inhibitors (TKI) targeting Epidermal Growth Factor Receptors (EGFR) is an important clinical toxicity in oncology that remains poorly understood. This study aimed to identify histological and molecular changes within the intestine following lapatinib to elucidate mechanisms of diarrhoea related to treatment with this dual EGFR TKI.

METHODS AND MATERIALS

Male albino Wistar rats were orally gavaged lapatinib at 100, 240 or 500 mg/kg daily for 4 weeks and assessed for indicators of gastrointestinal injury at the end of each week. Lapatinib in combination with weekly paclitaxel (9 mg/kg i.p.) was also assessed for cumulative injury. At each time point, blood was collected for biochemical analysis. Sections or jejunum and colon were also collected and underwent immunohistochemistry and RT-PCR to detect markers of EGFR pathway signalling, and morphometric analysis to assess changes in mucosal architecture.

RESULTS

Lapatinib (with or without paclitaxel co-treatment) caused dose-dependent changes in crypt length, mitotic rate and goblet cell morphology. Jejunal crypt expression of EGFR and ErbB2 were decreased, whilst no changes in Erk1/2 were observed. Markers of apoptosis (caspase-3) and proliferation (Ki-67) were only significantly altered in rats treated with both lapatinib and paclitaxel.

CONCLUSIONS

In our novel rat model of lapatinib-induced diarrhoea we have shown that changes in small intestinal morphometry and expression of EGFR are associated with diarrhoea. Further research is required to test intervention agents for the prevention of diarrhoea.

Development of the rat model of lapatinib-induced diarrhoea

Targeted therapy of cancer is often associated with clinically significant diarrhoea; however, the mechanisms underpinning this adverse effect are currently unknown. Diarrhoea following treatment with tyrosine kinase inhibitors (TKIs) of EGFR is particularly troublesome. Until recently, understanding of EGFR TKI-induced diarrhoea has been limited to clinical observation. However, our group has recently developed the first rat model of EGFR TKI-induced diarrhoea. This paper reviews the published and unpublished findings.

Optimal tolerability and high efficacy of a modified schedule of lapatinib-capecitabine in advanced breast cancer patients

PURPOSE

Diarrhea in relation to the lapatinib-capecitabine regimen is a common and debilitating side effect which may interfere with optimal treatment delivery. We performed a post hoc analysis in human epidermal growth factor receptor 2-positive advanced breast cancer patients treated with a modified schedule in its administration, aimed primarily to evaluate grade (G) ≥ 2 diarrhea incidence and, secondarily, treatment efficacy.

PATIENTS AND METHODS

Treatment schedule consisted of lapatinib 1,250 mg daily for the first 10 days, then in combination with capecitabine, 2,000 mg/m(2), starting day 11 for the first cycle, and thereafter from day 8, for 14 days of a 21-day cycle, in 3 daily administrations. Lapatinib was dissolved in water, and cholestyramine was continuously given twice a day.

RESULTS

Among 38 patients treated and analyzed, the incidence of G ≥ 2 diarrhea was 13.2 %. In 28 patients diarrhea was not observed, while G1-2 diarrhea was reported in 9 (23.7 %) patients; a single episode of G3 diarrhea was observed in 1 (2.6 %) patient. Overall response rate was 34.2 %, clinical benefit 55.3 %, and median progression-free survival 10 months.

CONCLUSION

The results of the present post hoc analysis are very encouraging, both in terms of tolerability and treatment efficacy, and all data compare favorably with previous reports of "conventional" administration of the lapatinib-capecitabine regimen.

Phase I study and biomarker analysis of lapatinib and concurrent radiation for locally advanced breast cancer

PURPOSE

This phase I study assessed the toxicity and safety of combining daily lapatinib with radiation therapy. Sequential tumor biopsies were obtained to evaluate changes in biomarkers, such as epidermal growth factor receptor (EGFR) and human EGFR-2 (HER2) signaling pathways.

METHODS

Eligibility for this dose-escalation study included unresectable and locally recurrent or chemotherapy-refractory and locally advanced breast cancer, and adequate organ function. Patients underwent three serial biopsies: at baseline, after 1 week of lapatinib alone, and after 1 week of lapatinib and radiation. Endpoints included determination of toxicity, maximum tolerated dose, and analysis of the effect of lapatinib with or without radiation on EGFR and HER2 signaling pathways by immunohistochemistry.

RESULTS

Doses of lapatinib up to 1,500 mg/day were well tolerated. Toxicity of grade 3 or more was limited to radiation dermatitis and pain. Out of 19 patients treated, in field responses per response evaluation criteria in solid tumors criteria were complete in four patients and partial in six patients. Serial biopsies were obtained in 16 patients with no complications. Total Her2 was relatively unchanged while phospho-Her2, phospho-Akt, and phospho-ERK showed variable responses to both lapatinib alone and dual therapy with lapatinib and radiation.

CONCLUSIONS

The combination of lapatinib and radiation was well tolerated in this patient cohort. Overall local response rates were comparable to those reported in other studies in this patient population. Biopsies were safely performed at all time points. Inhibition of HER2 and downstream signaling pathways was identified, although no strong correlation with response was seen.

An European Organisation for Research and Treatment of Cancer phase I study of lapatinib and docetaxel as neoadjuvant treatment for human epidermal growth factor receptor 2 (HER2) positive locally-advanced/inflammatory or large operable breast cancer

BACKGROUND

Lapatinib is an effective anti-HER2 therapy in advanced breast cancer and docetaxel is one of the most active agents in breast cancer. Combining these agents in pre-treated patients with metastatic disease had previously proved challenging, so the primary objective of this study aimed to determine the maximum tolerated dose (MTD) in treatment-naive patients, by identifying acute dose-limiting toxicities (DLT) during cycle 1 in the first part of a phases 1-2 neoadjuvant European Organisation for Research and Treatment of Cancer (EORTC) trial.

PATIENTS AND METHODS

Patients with large operable or locally-advanced HER2 positive breast cancer were treated with continuous lapatinib, and docetaxel every 21days for 4 cycles. Dose levels (DLs) were: 1000/75, 1250/75, 1000/85, 1250/85, 1000/100 and 1250/100 (mg/day)/(mg/m(2)).

RESULTS

Twenty-one patients were included. Two DLTs occurred at dose level 5 (1000/100); one grade 4 neutropenia ≥ 7days and one febrile neutropenia. A further 3 patients were therefore treated at the same dose with prophylactic granulocyte-colony stimulating factor (G-CSF), and 3 patients at dose level 6. No further DLTs were observed.

CONCLUSIONS

Our recommended dose for phase II is lapatinib 1000mg/day and docetaxel 100mg/m(2) with G-CSF in HER2 positive non-metastatic breast cancer. The dose of lapatinib should have been 1250mg/day but we were mindful of the high rate of treatment discontinuation in GeparQuinto with lapatinib 1250mg/day combined with docetaxel. No grade 3-4 diarrhoea was observed. Pharmacodynamics analysis suggests that concomitant medications altering P-glycoprotein activity (in addition to lapatinib) can modify toxicity, including non-haematological toxicities. This needs verification in larger trials, where it may contribute to understanding the sources of variability in clinical toxicity and treatment discontinuation.

Development of a rat model of oral small molecule receptor tyrosine kinase inhibitor-induced diarrhea

Orally administered small molecule receptor tyrosine kinase inhibitors (RTKIs) are increasingly common treatments for cancer, both alone and in combination with chemotherapy. However, their side effect profiles and the underlying mechanisms of such are not yet fully elucidated. Management of their most common dose limiting side effect, diarrhea, has been hampered by a lack of suitable animal models. We aimed to develop a clinically relevant rat model of RTKI-induced diarrhea that could be utilized for investigating supportive care interventions and pharmacokinetics. Albino Wistar rats were treated daily for 4 weeks with various concentrations of lapatinib to determine the optimal dose for development of diarrhea. This was then followed by an experiment with addition of paclitaxel once weekly for 4 weeks to observe effects of combination drug treatment on diarrhea. Data regarding animal tolerance to the treatment, organ weights, circulating lapatinib concentration and histopathology were collected weekly. Lapatinib caused diarrhea in rats that was dose-dependent. Diarrhea occurred without causing significant intestinal histopathology. Follow up experiments are currently underway to determine the exact pathogenesis and mechanisms of lapatinib-induced diarrhea and potential protective strategies.

[Targeted therapy and breast cancer: state of the art]

CONTEXT

Scientific advances in molecular biology and understanding of oncogenesis have lead to anticancer molecular targeted therapies. They encompass monoclonal antibodies binding to active membrane epitopes and small molecules interfering with enzymatic reactions essential to cancer cell survival (oncogene addiction). These pathways may be optimal targets. Clinical benefits achieved using these targeted agents have been outstanding both in localized and metastatic disease.

METHOD

We conducted a survey of literature analyzing activity and safety of targeted agents approved by FDA and/or FDA for the treatment of patients with breast cancer: anti-HER2 and antiangiogenic agents.

RESULTS

Activity and main toxicities of these targeted agents are described according to signaling pathway targeted as well as stage of breast cancer.

CONCLUSIONS

Availability of these targeted therapies has indeed transformed the outcome of subgroups of breast cancer to the expense of acceptable and manageable side effects, as compared to classical cytotoxics to which they are nevertheless combined.

Management of elderly patients with breast cancer: updated recommendations of the International Society of Geriatric Oncology (SIOG) and European Society of Breast Cancer Specialists (EUSOMA)

As the mean age of the global population increases, breast cancer in older individuals will be increasingly encountered in clinical practice. Management decisions should not be based on age alone. Establishing recommendations for management of older individuals with breast cancer is challenging because of very limited level 1 evidence in this heterogeneous population. In 2007, the International Society of Geriatric Oncology (SIOG) created a task force to provide evidence-based recommendations for the management of breast cancer in elderly individuals. In 2010, a multidisciplinary SIOG and European Society of Breast Cancer Specialists (EUSOMA) task force gathered to expand and update the 2007 recommendations. The recommendations were expanded to include geriatric assessment, competing causes of mortality, ductal carcinoma in situ, drug safety and compliance, patient preferences, barriers to treatment, and male breast cancer. Recommendations were updated for screening, primary endocrine therapy, surgery, radiotherapy, neoadjuvant and adjuvant systemic therapy, and metastatic breast cancer.

Target therapy in elderly breast cancer patients

Substantial progress has been made in the management of breast cancer by targeting HER2 and VEGF pathways. Although the efficacy and safety of target therapy in breast cancer have been established, no specific phase III trial has addressed these issues in the elderly population and the only data available derive from subanalyses or retrospective series. The aim of this review is to summarize the available evidence in this special population and to encourage further well designed studies in elderly breast cancer patients.

A phase I study of capecitabine, oxaliplatin, and lapatinib in metastatic or advanced solid tumors

BACKGROUND

Metastatic colorectal cancer (mCRC) is a leading cause of cancer-related mortality in the United States, and new treatment options are needed. This phase I study investigated a novel regimen combining 2 chemotherapy drugs with proven efficacy in mCRC (capecitabine and oxaliplatin) with a tyrosine kinase inhibitor (lapatinib). Lapatinib has already been approved by the US Food and Drug Administration for treatment of selected cases of breast cancer.

PATIENTS AND METHODS

Patients with solid tumors responsive to fluoropyrimidines or oxaliplatin were eligible for enrollment. Treatment was given over a 21-day cycle with a fixed dosing of intravenous oxaliplatin of 130 mg/m(2) on day 1. Capecitabine and lapatinib were given orally at escalating doses, starting at capecitabine 1500 mg/m(2)/day on days 1-14 and lapatinib 1000 mg daily on days 1-21.

RESULTS

Ten patients received treatment per study protocol. All had received previous systemic treatment. Diarrhea was one of the most common side effects and accounted for nearly all grade 3/4 toxicity. The starting dose level was determined to be the maximum tolerated dose. One patient with pancreatic cancer had evidence of a partial response. Three other patients demonstrated stable disease. There were no complete responses.

CONCLUSION

Results of this study suggest the regimen of capecitabine, oxaliplatin, and lapatinib has some efficacy in types of advanced or metastatic solid malignancies with known responsiveness to fluoropyrimidines or oxaliplatin. Further research may help determine whether this regimen can improve on the response rates seen with current standard regimens for mCRC.

Blockade of the HER family of receptors in the treatment of HER2-positive metastatic breast cancer

Breast cancer is the most common type of cancer among women and the second leading cause of cancer death in the United States. Metastatic breast cancer is considered incurable, and treatment is aimed at palliating symptoms, achieving remission, and prolonging survival. Treatment options for metastatic disease vary based on tumor surface markers and clinical factors in an individual patient and include cytotoxic chemotherapy, hormonal therapy, biological therapy, or some combination of these. An important molecular determinant of therapy is the human epidermal growth factor receptor 2 (HER2) positivity of the tumor, which affects response to HER2-targeted treatment. HER2 is a member of the human epidermal growth factor receptor family of receptor tyrosine kinases, also known as the HER family, which activates signaling that promotes tumorigenic cellular processes such as proliferation and evasion of apoptosis. Several targeted agents, including monoclonal antibodies and tyrosine kinase inhibitors that inhibit one or more HER family receptors have been developed that affect signaling through this pathway. Some of these, such as trastuzumab and lapatinib, have been approved for breast cancer treatment. Resistance to therapy is a challenge that limits the duration of benefit achieved with these agents. Therefore, combinations of HER family-targeted agents with other therapies such as cytotoxic agents, hormonal therapy, or inhibitors of other cellular pathways, are being developed to exploit synergy and overcome resistance mechanisms. Here we review the HER family-targeted agents currently approved or in development for HER2-positive metastatic breast cancer with a focus on strategies to overcome tumor resistance.

Lapatinib activity in premalignant lesions and HER-2-positive cancer of the breast in a randomized, placebo-controlled presurgical trial

Dual epidermal growth factor receptor (EGFR) and HER2 targeting with the tyrosine kinase inhibitor lapatinib is approved for treating advanced HER2-positive breast cancer and can prevent estrogen receptor (ER)-negative mammary tumors in HER2 transgenic mouse models. Ki-67 labeling index (LI) has prognostic and predictive value and can be used to screen drugs' therapeutic and preventive potential in a clinical model of short-term presurgical therapy of breast cancer. We conducted a randomized, placebo-controlled trial of lapatinib (1500 mg/d) administered orally for three weeks between biopsy and surgery in 60 women with HER-2-positive breast cancer to assess lapatinib biomarker (including the primary endpoint, Ki-67 LI) and clinical activity in invasive breast cancer, adjacent ductal intraepithelial neoplasia (DIN, which comprises ductal carcinoma in situ and atypical ductal hyperplasia), and distant ductal hyperplasia without atypia (DH). Ki-67 LI increased progressively in association with disease stage, increasing in the placebo arm, for example, by medians of 3% in DH to 20% in DIN to 30% in invasive cancer. Ki-67 LI in cancer tissue decreased by a mean (±SD) of 9.3% (±34.2) in the lapatinib arm and increased by 15.1% (±30.9) in the placebo arm (P = 0.008). Compared with placebo, lapatinib reduced Ki-67 significantly more in ER-negative tumors (by 34.8%; P = 0.01) but not significantly more in ER-positive tumors (by 12.3%; P = 0.2) and reduced Ki-67 more (nonsignificantly) in cytosol PTEN-overexpressing tumors (P = 0.057). The prevalence of DIN in post-treatment surgical specimens of both arms was similar (70%-76%), with a median Ki-67 of 15% (range, 5%-35%) on lapatinib versus 20% (5%-60%) on placebo (P = 0.067). The prevalence of DH also was similar in both arms (>90%), with a median Ki-67 of 1% (1%-7%) on lapatinib versus 3% (1%-5%) on placebo (P = 0.006). Other results of lapatinib versus placebo, respectively, were as follows: Median tumor diameter at surgery of 18 mm (11 mm-57 mm) versus 24 mm (10 mm-37 mm; P = 0.009); partial response of 13.6% versus 3.7%, stable disease of 59.1% versus 40.7%, and progression of 27.3% versus 55.6% (P-trend = 0.035). In conclusion, short-term lapatinib decreased cell proliferation in DIN, DH, and invasive HER-2-positive (especially ER-negative) breast cancer, thus providing the rationale for further clinical development of lapatinib for breast cancer prevention in high-risk patients, including those with HER-2-positive DIN.

Combination therapy of lapatinib and Capecitabine for ErbB2-positive metastatic or locally advanced breast cancer: results from the Lapatinib Expanded Access Program (LEAP) in Central and Eastern Europe

BACKGROUND

The Lapatinib Expanded Access Program (LEAP) was initiated in 45 countries to provide lapatinib in combination with capecitabine to patients with ErbB2 (HER2)-positive breast cancer already treated with anthracyclines, taxanes and trastuzumab. We report the results from 12 Central and Eastern European countries.

PATIENTS AND METHODS

By 30 September 2008, 293 patients were enrolled. Patients were monitored for serious adverse events (SAEs) and for any decrease in left ventricular ejection fraction (LVEF). Overall survival and progression-free survival were also assessed.

RESULTS

Mean treatment duration was 30 weeks; 107 patients (36.5%) discontinued therapy during the study, mainly due to disease progression (n = 86; 29.4%). A total of 78 SAEs were reported from 47 patients; the most frequently reported was diarrhoea (13 reports). Treatment had a relatively small effect on LVEF. Decreases were minor (0 to < 20%) in 61% of patients at the end of the study. During the study, 3 patients had decreased LVEF meeting the definition of an SAE; these events all resolved. Median overall and median progression-free survival were 37.6 and 21.1 weeks, respectively.

CONCLUSIONS

Heavily pretreated patients with ErbB2-positive locally advanced or metastatic breast cancer may benefit from treatment with lapatinib and capecitabine, with a low risk of cardiac toxicity.

Her2-targeted therapies for gastric cancer

Gastric cancer is one of the most common malignancies and represents a major cause of cancer-related death in China. Her2 plays an important role in the activation of Her/ErbB family receptors and post-receptor signal transduction events. The rates of Her2 expression in gastric cancer range from 11.9% to 23.7%. Her2 expression correlates with Laruen's classification, location of primary tumor, and poor outcome in gastric cancer. Her2-targeted therapeutic strategies include the use of monoclonal antibodies and small molecule tyrosine kinase inhibitors. ToGA study is the first phase III randomized clinical trial to evaluate the efficacy and safety of trastuzumab, an anti-Her2 monoclonal antibody, in the first-line treatment of advanced and metastatic gastric cancer. Interestingly, trastuzumab could remarkably prolong the median overall survival of patients with gastric cancer to 13.8 mo. However, this trial also triggers much controversy over Her2-targeted therapies for gastric cancer.

Lapatinib side-effect management

Lapatinib is an oral dual tyrosine kinase inhibitor targeting epidermal growth factor receptor and HER2. Diarrhea and dermatologic adverse events are reported commonly by patients treated with lapatinib. Diarrhea can range from mild to severe based on the agents used in combination with lapatinib. The adverse events may diminish quality of life, reduce treatment adherence, and lead to discontinuation of therapy. Consequently, proactive management of diarrhea is crucial, especially in patients receiving lapatinib in combination with other agents that also cause diarrhea. As the utility of lapatinib expands, crucial proactive diarrhea-management and dose-reduction strategies are evolving to decrease the likelihood of grade 3 or 4 toxicity. With regard to dermatologic adverse events, most are mild to moderate in severity, are of limited duration, and frequently do not require treatment intervention. However, in some patients, management of dermatologic adverse events is of great importance. This article reviews data regarding diarrhea and dermatologic adverse events in patients treated with lapatinib and summarizes the key role that oncology nurses play in educating patients about the potential for adverse events and the importance of preventive measures, ongoing surveillance, appropriate treatment, and dose reductions.

Phase II Study to Evaluate the Efficacy and Safety of Neoadjuvant Lapatinib Plus Paclitaxel in Patients With Inflammatory Breast Cancer

Purpose

We conducted a phase II, open-label, multicenter study to evaluate the efficacy, safety, and tolerability of daily lapatinib plus weekly paclitaxel in treatment-naïve patients with inflammatory breast cancer (IBC).

Patients and Methods

The primary end point was pathologic complete response (pCR). Secondary end points included combined clinical response rate (based on Response Evaluation Criteria in Solid Tumors (RECIST) criteria and clinically evaluable skin disease criteria). Patients were assigned to either cohort A (human epidermal growth factor receptor 2 [HER2] 2+ or 3+ by immunohistochemistry [IHC] or fluorescent in situ hybridization [FISH] –amplified ± epidermal growth factor receptor [EGFR] expression) or cohort B (HER2-negative/EGFR-positive). A subpopulation of cohort A considered HER2-positive by the current definition of overexpression (3+ by IHC or FISH-amplified) was also analyzed. Patients received lapatinib at 1,500 mg/d for 14 days, then lapatinib at 1,500 mg/d plus weekly paclitaxel (80 mg/m2) for 12 weeks, followed by surgical resection or additional chemotherapy.

Results

Forty-nine women were enrolled (cohort A, n = 42; cohort B, n = 7). Cohort B was terminated because of slow accrual and lack of efficacy observed in IBC patients with HER2-negative/EGFR-positive tumors enrolled onto the parallel study, EGF103009. pCR occurred in 18.2% (95% CI, 5.2% to 40.3%) of cohort A patients. Combined clinical response rate was 78.6% (95% CI, 63.2% to 89.7%) in all cohort A patients and 78.1% (95% CI, 60.0% to 90.7%) in the HER2-positive subset. Common adverse events included diarrhea, rash, alopecia, and nausea (> 50% of patients in both cohorts). The incidence of grade 3 diarrhea was 55%.

Conclusion

Lapatinib monotherapy for 14 days followed by lapatinib plus paclitaxel for 12 weeks provided clinical benefit in IBC patients with HER2-overexpressing tumors without unexpected toxicity.