The Global Need for a Trastuzumab Biosimilar for Patients With HER2-Positive Breast Cancer.

Trastuzumab improves survival outcomes for patients with HER2-positive (HER2+) breast cancer, yet not all such women receive this important therapy. Trastuzumab was approved by the US Food and Drug Administration in 1998 and the European Medicines Agency in 2000 as treatment for HER2+ metastatic breast cancer (MBC). Observational studies between 2000 and 2015 in patients with HER2+ MBC suggest that nearly 12% in the United States, 27% to 54% in Europe, and 27.1% to 49.2% in China did not receive trastuzumab or any other HER2-targeted agent as first- and/or later-line for treatment of metastatic disease. In 2006, both agencies approved trastuzumab as adjuvant therapy for patients with HER2+ early breast cancer (EBC). Observational studies on real-world treatment patterns for HER2+ EBC between 2005 and 2015 suggest that 19.1% to 59.5% of patients across regions of North America, Europe, Australia, New Zealand, and China did not receive (neo)adjuvant trastuzumab. Data suggest that some patient subgroups, including older patients, those with HER2+/hormone receptor-positive disease, and women with small and/or node-negative HER2+ tumors, were less likely to receive anti-HER2 therapy. Barriers to accessing trastuzumab are multifactorial and include issues related to drug funding and high treatment costs for patients that have been reported worldwide. Herein, we review available literature on the use of, and barriers to, treatment with trastuzumab in patients with HER2+ breast cancer. We also discuss how the availability of safe and effective biosimilars might increase access to trastuzumab and allow greater use of anti-HER2 therapy, potentially improving patient outcomes.

Process mining routinely collected electronic health records to define real-life clinical pathways during chemotherapy.

BACKGROUND: There is growing interest in the use of routinely collected electronic health records to enhance service delivery and facilitate clinical research. It should be possible to detect and measure patterns of care and use the data to monitor improvements but there are methodological and data quality challenges. Driven by the desire to model the impact of a patient self-test blood count monitoring service in patients on chemotherapy, we aimed to (i) establish reproducible methods of process-mining electronic health records, (ii) use the outputs derived to define and quantify patient pathways during chemotherapy, and (iii) to gather robust data which is structured to be able to inform a cost-effectiveness decision model of home monitoring of neutropenic status during chemotherapy. METHODS: Electronic Health Records at a UK oncology centre were included if they had (i) a diagnosis of metastatic breast cancer and received adjuvant epirubicin and cyclosphosphamide chemotherapy or (ii) colorectal cancer and received palliative oxaliplatin and infusional 5-fluorouracil chemotherapy, and (iii) were first diagnosed with cancer between January 2004 and February 2013. Software and a Markov model were developed, producing a schematic of patient pathways during chemotherapy. RESULTS: Significant variance from the assumed care pathway was evident from the data. Of the 535 patients with breast cancer and 420 with colorectal cancer there were 474 and 329 pathway variants respectively. Only 27 (5%) and 26 (6%) completed the planned six cycles of chemotherapy without having unplanned hospital contact. Over the six cycles, 169 (31.6%) patients with breast cancer and 190 (45.2%) patients with colorectal cancer were admitted to hospital. CONCLUSION: The pathways of patients on chemotherapy are complex. An iterative approach to addressing semantic and data quality issues enabled the effective use of routinely collected patient records to produce accurate models of the real-life experiences of chemotherapy patients and generate clinically useful information. Very few patients experience the idealised patient pathway that is used to plan their care. A better understanding of real-life clinical pathways through process mining can contribute to care and data quality assurance, identifying unmet needs, facilitating quantification of innovation impact, communicating with stakeholders, and ultimately improving patient care and outcomes.

'Tablet burden' in patients with metastatic breast cancer.

UNLABELLED: The implications for patients with cancer, of the 'tablet burden' resulting from increasing use of oral anticancer drugs and medication for co-morbidities have not previously been well explored. AIM: We sought to (i) quantify tablet burden in women with metastatic breast cancer (MBC), (ii) establish which groups of drug contribute most to this burden and (iii) gain insight into patients' attitudes towards oral anti-cancer treatment. METHODS: One hundred patients with MBC anonymously completed a questionnaire describing their medication histories and attitudes towards their tablets. RESULTS: The patients (mean age 60, range 31-95) were all female and taking a median of six tablets (range 0-31) daily; 37 patients were taking >10 tablets. Oral anticancer treatment constituted the category of treatment taken by the highest proportion of patients, followed by symptomatic cancer treatments, proton pump inhibitors and cardiovascular medication. Numerically, however, symptomatic drugs accounted for 44% of all tablets and specific anti-cancer treatment for 15%; medication not directly related to the cancer accounted for the remaining 40% of tablets. A quarter of patients reported inconvenience in taking their tablets, the main reason being tablet size and one third reported forgetting their tablets at least once a week. Nearly two thirds of patients expressing a preference favoured oral anticancer treatment, the commonest reason being greater convenience. CONCLUSION: Tablet burden is considerable for many patients with MBC and can be problematic. A significant proportion of tablets represent treatment for co-morbidities, the significance of which may be questionable in women with MBC.

Population pharmacokinetic-pharmacodynamic modelling and simulation of neutropenia induced by TP300, a novel topoisomerase I inhibitor.

OBJECTIVES: TP300 is a novel topoisomerase I inhibitor with neutropenia as a significant toxicity. We developed and evaluated a pharmacokinetic-pharmacodynamic (PK-PD) model, using data from Phase I and II trials to predict neutrophil decrease in patients treated with TP300. METHODS: Plasma drug concentrations of TP300, its active form TP3076 and active metabolite TP3011 and absolute neutrophil counts (ANCs) from a Phase I trial were analysed as a training dataset. A two-plus-two-compartment model was applied to the pharmacokinetics of TP3076 and TP3011. A semi-mechanistic model was used to describe the PK-PD relationship between the plasma concentration of TP3076 and TP3011, and changes in ANC. KEY FINDINGS: The model fitted well to plasma concentrations of TP3076 and TP3011. Model appropriateness was confirmed in a Phase II trial validation dataset. Body weight and liver biochemistry values were identified as covariates. A semi-mechanistic PK-PD model was applied and the longitudinal decrease in ANC was simulated. Neutrophil counts reached their nadir approximately 2 weeks after administration of TP300, and the proportion of subjects affected increased with dose. CONCLUSIONS: This PK-PD model to predict neutropenia following treatment with TP300 fitted well the decrease in ANC with total concentration of TP3076 and TP3011.

Loading doses for costly cancer biologicals: a cause for concern or tilting at windmills?

The emergence of novel, effective but expensive biological therapies is significantly improving outcomes for many patients with cancer, but also substantially increasing treatment costs. Monoclonal antibodies with long half-lives have often been developed using loading doses to hasten the achievement of a therapeutic dose. Although the benefits of loading doses have not been proven, we caution against abandoning this practice on uncertain theoretical grounds. Rather, the issue of loading doses should be seen in the broader context of how best to define the optimal dose, schedule and duration of treatment through novel clinical trial designs.

Assessment of the validity of a population pharmacokinetic model for epirubicin.

AIMS: The aim of this study was to evaluate a population model for epirubicin clearance using internal and external validation techniques. METHODS: Jackknife samples were used to identify outliers in the population dataset and individuals influencing covariate selection. Sensitivity analyses were performed in which serum aspartate transaminase (AST) values (a covariate in the population model) or epirubicin concentrations were randomly changed by +/-10%. Cross-validation was performed five times, on each occasion using 80% of the data for model development and 20% to assess the performance of the model. External validation was conducted by assessing the ability of the population model to predict concentrations and clearances in a separate group of 79 patients. RESULTS: Structural parameter estimates from all jackknife samples were within 7.5% of the final population estimates and examination of log likelihood values indicated that the selection of AST in the final model was not due to the presence of outliers. Alteration of AST or epirubicin concentrations by +/-10% had a negligible effect on population parameter estimates and their precision. In the cross-validation analysis, the precision of clearance estimates was better in patients with AST concentrations>150 U l-1. In the external validation, epirubicin concentrations were over-predicted by 81.4% using the population model and clearance values were also poorly predicted (imprecision 43%). CONCLUSIONS: The results of internal validation of population pharmacokinetic models should be interpreted with caution, especially when the dataset is relatively small.

Xeloda in Adjuvant Colon Cancer Therapy (X-ACT) trial: overview of efficacy, safety, and cost-effectiveness.

The X-ACT (Xeloda in Adjuvant Colon Cancer Therapy) trial compared the efficacy and safety of the oral fluoropyrimidine capecitabine with bolus 5-fluorouracil (5-FU)/leucovorin (LV; Mayo Clinic regimen) as adjuvant therapy for stage III colon cancer. A total of 1987 patients were enrolled at 164 centers worldwide. Disease-free survival (primary study endpoint) in the capecitabine arm was at least equivalent to that in the 5-FU/LV arm; the upper limit of the hazard ratio was significantly (P < 0.001) below the predefined margins for noninferiority. Capecitabine was also associated with significantly fewer fluoropyrimidine-related grade 3/4 adverse events (AEs; P < 0.001) and fewer AE-related hospital admissions/days than 5-FU/LV. Pharmacoeconomic analyses performed in several countries show that the savings in direct costs (drug administration and AE-related costs) associated with capecitabine versus 5-FU/LV offset the acquisition costs of the drug. Furthermore, capecitabine reduces patient travel time and costs, making it a "dominant" strategy (ie, less costly and more effective) in the adjuvant setting. In conclusion, efficacy, safety, convenience, and cost findings from the X-ACT trial show that capecitabine offers at least equivalent clinical benefit compared with bolus 5-FU/LV and can replace intravenous 5-FU/LV in the adjuvant treatment of stage III colon cancer. The X-ACT trial has not only helped to better define the role of capecitabine but has also broadened the options available to patients with early-stage disease to include a uniquely effective oral outpatient treatment.

Capecitabine plus docetaxel combination therapy.

BACKGROUND: For patients with anthracycline-pretreated metastatic breast carcinoma, capecitabine plus docetaxel significantly increased overall survival compared with docetaxel alone. The current study evaluated the cost-effectiveness of the capecitabine/docetaxel combination versus docetaxel monotherapy, comparing the gain in quality-adjusted survival with associated health care costs. METHODS: Patients were randomized to receive 21-day cycles of oral capecitabine 1250 mg/m2 twice daily, on Days 1-14, plus docetaxel 75 mg/m2 Day 1 (n = 255), or docetaxel 100 mg/m2 on Day 1 (n = 256). Health and cost outcomes in the two arms were compared, and cost-effectiveness was estimated. Data on survival time and medical care resource use were prospectively collected in the trial. Costs associated with medical care resource use and quality-of-life adjustments were obtained from the published literature. The incremental cost-effectiveness ratio was calculated as the cost per quality-adjusted life year (QALY) gained. RESULTS: Capecitabine/docetaxel increased the median overall survival by 3 months compared with docetaxel alone (14.5 vs. 11.5 months). The mean quality-adjusted survival was increased by 1.8 months in the capecitabine/docetaxel group. The total medical-resource utilization cost per patient was 8.9% higher with the combination: 24,475 dollars for combination therapy versus 22,477 dollars for single-agent docetaxel. The mean cost per QALY gained with combination therapy was 13,558 dollars (standard deviation, 6742 dollars). Cost savings due to reduced docetaxel dose and hospital use were the major cost offsets with the combination. Sensitivity analyses showed that varying the mean hospital cost per day from the 5th to the 95th percentile resulted in cost-utility ratios ranging from 20,326 dollars to as low as 6360 dollars. CONCLUSIONS: Capecitabine/docetaxel was a cost-effective treatment in patients with anthracycline-pretreated advanced breast carcinoma, and had an incremental cost-effectiveness ratio that compares very favorably with that of many other oncology therapies.

Treatment for anthracycline-pretreated metastatic breast cancer.

As a result of increasing anthracycline use earlier in the course of breast cancer, oncologists are frequently faced with the challenge of treating patients whose disease has progressed during or following anthracycline therapy or who are ineligible for further anthracycline therapy. Many of these women remain candidates for cytotoxic chemotherapy, and several treatment options exist. Until recently, the taxanes, docetaxel in particular, were widely regarded as the most effective therapy for these patients, based on a survival advantage observed with docetaxel. However, a recent phase III study demonstrated that the addition of capecitabine to docetaxel results in superior overall survival (with a 3-month improvement in median survival), superior time to disease progression, and a superior response rate, with a manageable safety profile. Capecitabine/docetaxel is the first cytotoxic combination to improve survival over standard monotherapy in patients with anthracycline-pretreated metastatic breast cancer. Moreover, the survival benefit can be attributed to the addition of capecitabine, as it was achieved despite the lower dose of docetaxel administered in the combination arm. Quality of life was maintained with capecitabine/docetaxel combination therapy, which further supports the use of this regimen in patients with anthracycline-pretreated metastatic breast cancer. Pharmacoeconomic modeling using the data from the phase III trial has shown that the capecitabine/docetaxel combination therapy is highly cost effective when compared with other cancer treatments that improve survival. This review describes several treatment options for patients with anthracycline-pretreated breast cancer, including the phase III data (efficacy, tolerability, quality of life, and pharmacoeconomics) for capecitabine plus docetaxel in this setting.