Is trastuzumab a cost-effective treatment for breast cancer?

Cost-utility analyses of drug therapies in breast cancer: a systematic review

The economic evaluation (EE) of health care products has become a necessity. Their quality must be high in order to trust the results and make informed decisions. While cost-utility analyses (CUAs) should be preferred to cost-effectiveness analyses in the oncology area, the quality of breast cancer (BC)-related CUA has been given little attention so far. Thus, firstly, a systematic review of published CUA related to drug therapies for BC, gene expression profiling, and HER2 status testing was performed. Secondly, the quality of selected CUA was assessed and the factors associated with a high-quality CUA identified. The systematic literature search was conducted in PubMed, MEDLINE/EMBASE, and Cochrane to identify published CUA between 2000 and 2014. After screening and data extraction, the quality of each selected CUA was assessed by two independent reviewers, using the checklist proposed by Drummond et al. The analysis of factors associated with a high-quality CUA (defined as a Drummond score ≥7) was performed using a two-step approach. Our systematic review was based on 140 CUAs and showed a wide variety of methodological approaches, including differences in the perspective adopted, the time horizon, measurement of cost and effectiveness, and more specially health-state utility values (HSUVs). The median Drummond score was 7 [range 3-10]. Only one in two of the CUA (n = 74) had a Drummond score ≥7, synonymous of "high quality." The statistically significant predictors of a high-quality CUA were article with "gene expression profiling" topic (p = 0.001), consulting or pharmaceutical company as main location of first author (p = 0.004), and articles with both incremental cost-utility ratio and incremental cost-effectiveness ratio as outcomes of EE (p = 0.02). Our systematic review identified only 140 CUAs published over the past 15 years with one in two of high quality. It showed a wide variety of methodological approaches, especially focused on HSUVs. A critical appraisal of utility values is necessary to better understand one of the main difficulties encountered by authors and propose areas for improvement to increase the quality of CUA. Since the last 5 years, there is a tendency toward an improvement in the quality of these studies, probably coupled with economic context, a better and widely spreading of recommendations and thus appropriation by medical practitioners. That being said, there is an urgent need for mandatory use of European and international recommendations to ensure quality of such approaches and to allow easy comparison.

A review of systematic reviews of the cost-effectiveness of hormone therapy, chemotherapy, and targeted therapy for breast cancer

Breast cancer is a global health concern. In fact, breast cancer is the primary cause of death among women worldwide and constitutes the most expensive malignancy to treat. As health care resources are finite, decisions regarding the adoption and coverage of breast cancer treatments are increasingly being based on "value for money," i.e., cost-effectiveness. As the evidence about the cost-effectiveness of breast cancer treatments is abundant, therefore difficult to navigate, systematic reviews of published systematic reviews offer the advantage of bringing together the results of separate systematic reviews in a single report. As a consequence, this paper presents an overview of systematic reviews of the cost-effectiveness of hormone therapy, chemotherapy, and targeted therapy for breast cancer to inform policy and reimbursement decision-making. A systematic review was conducted of published systematic reviews documenting cost-effectiveness analyses of breast cancer treatments from 2000 to 2014. Systematic reviews identified through a literature search of health and economic databases were independently assessed against inclusion and exclusion criteria. Systematic reviews of original evaluations were included only if they targeted breast cancer patients and specific breast cancer treatments (hormone therapy, chemotherapy, and targeted therapy only), documented incremental cost-effectiveness ratios, and were reported in the English language. The search strategy used a combination of these key words: "breast cancer," "systematic review/meta-analysis," and "cost-effectiveness/economics." Data were extracted using predefined extraction forms and qualitatively appraised using the assessment of multiple systematic reviews (AMSTAR) tool. The literature search resulted in 511 bibliographic records, of which ten met our inclusion criteria. Five reviews were conducted in the early-stage breast cancer setting and five reviews in the metastatic setting. In early-stage breast cancer, evidence about trastuzumab value differed by age. Trastuzumab was cost-effective only in women with HER2-positive breast cancer younger than 65 years and over a life-time horizon. The cost-effectiveness of trastuzumab in HER2-positive metastatic breast cancer yielded conflicting results. The same conclusions were reached in comparisons between vinorelbine and taxanes. In both early stage and advanced/metastatic breast cancer, newer aromatase inhibitors (AIs) have proved cost-effective compared to older treatments. This overview of systematic reviews shows that there is heterogeneity in the evidence concerning the cost-effectiveness of hormone therapy, chemotherapy, and targeted therapy for breast cancer. The cost-effectiveness of these treatments depends not only on the comparators but the context, i.e., adjuvant or metastatic setting, subtype of patient population, and perspective adopted. Decisions involving the cost-effectiveness of breast cancer treatments could be made easier and more transparent by better harmonizing the reporting of economic evaluations assessing the value of these treatments.

Economic evaluations of trastuzumab in HER2-positive metastatic breast cancer: a systematic review and critique

BACKGROUND

Published economic evaluations of trastuzumab for the treatment of HER2-positive metastatic breast cancer have arrived at different conclusions regarding the cost-effectiveness of trastuzumab, despite comparative efficacy being demonstrated by a small set of randomised controlled trials (RCTs).

OBJECTIVES

This article aims to provide insight into the quality of the evaluations and explore the possible drivers of the conflicting conclusions.

METHODS

A systematic literature review was conducted to identify all published economic evaluations that compared the incremental costs and outcomes of trastuzumab versus a comparator.

RESULTS

Fifteen economic evaluations were identified. In the evaluations that estimated efficacy using an RCT, the key drivers of the conclusions regarding cost-effectiveness were: the approach used to estimate overall survival in the control group given crossover to trastuzumab following progression in the trials; the inclusion of treatment beyond progression; inclusion of wastage due to unused vial portions, adverse events, and the cost of HER2 testing. Four evaluations used non-randomised approaches to estimate efficacy, thus introducing the potential for confounding. As a result these evaluations reported relatively optimistic estimates of comparative effectiveness. Finally the evaluations used different thresholds to determine whether treatment with trastuzumab was cost-effective.

CONCLUSION

There were numerous drivers of the different conclusions regarding the cost-effectiveness of trastuzumab, many of which are due to judgements made by the authors when translating data from RCTs. Many of the potential drivers were not identified by the published systematic reviews of economic evaluations and perhaps more remain unidentified because of inconsistent and limited reporting.

Is adjuvant trastuzumab a cost-effective therapy for HER-2/neu-positive T1bN0 breast cancer?

BACKGROUND

In light of clinical uncertainty and the high acquisition costs of trastuzumab, we examined the value for money associated with concurrent or sequential trastuzumab in women with HER-2/neu-positive breast cancer with small node-negative tumours (T1bN0).

MATERIALS AND METHODS

A probabilistic economic model was developed to estimate the likelihood of adjuvant trastuzumab meeting a $100 000 per quality-adjusted life year gained threshold over a range of 10-year recurrence risks by age. The primary analysis took an incremental approach, comparing trastuzumab plus chemotherapy with chemotherapy alone. A secondary analysis took an 'all-or-nothing' approach, comparing trastuzumab plus chemotherapy with neither treatment.

RESULTS

The primary analysis suggested that concurrent trastuzumab plus adjuvant chemotherapy was likely to meet the $100 000 threshold at recurrence risks of 29-35%. Sequential trastuzumab was less likely to meet such a threshold. The secondary analysis was more favourable for both trastuzumab strategies, but of limited relevance as clinical benefits were predominantly driven by chemotherapy without trastuzumab.

CONCLUSIONS

Concurrent trastuzumab plus adjuvant chemotherapy appears to offer favourable value for money at the upper ranges of baseline recurrence risks reported to date, although more precise estimates of underlying risk are required to confirm the cost-effectiveness of adjuvant trastuzumab in T1bN0 breast cancer.

Trastuzumab for HER2-Positive Metastatic Breast Cancer: Clinical and Economic Considerations

Trastuzumab is a recombinant humanized monoclonal antibody that selectively targets the extra-cellular domain of the HER2 receptor. It was approved by the FDA in September 1998 as the first targeted therapy for HER2-positive metastatic breast cancer, and has since led to significant improvements in the overall prognosis for patients with HER2-positive metastatic disease. The favourable benefit/risk profile associated with palliative trastuzumab has been demonstrated in a number of clinical trials that examined trastusumab as monotherapy or in combination with chemotherapy, endocrine therapy and other HER2 targeted agents. The clinical benefits of trastuzumab, however should also be examined within the context of its significant drug acquisition costs. This review highlights the significant findings from the landmark clinical trials of trastuzumab for metastatic HER2-positive breast cancer, and the potential “value for money” associated with its use in clinical practice.

Updated cost-effectiveness analysis of trastuzumab for early breast cancer: a UK perspective considering duration of benefit, long-term toxicity and pattern of recurrence

BACKGROUND

Trastuzumab has significantly improved survival outcomes for women with Human Epidermal growth factor Receptor 2 (HER2)-positive early breast cancer. Trastuzumab was established as a cost-effective adjuvant treatment in 2006. We present an updated cost-effectiveness analysis from the UK perspective, which explores assumptions about the duration of benefit from treatment, pattern of metastatic recurrence and long-term cardiac toxicity.

OBJECTIVE

The objective of this study was to calculate, from the UK NHS perspective, expected costs (year 2008 values) and benefits over the lifetime of an average cohort of women with HER2-positive early breast cancer treated with or without 1 year of adjuvant trastuzumab sequentially after chemotherapy.

METHODS

A cost-utility analysis was performed using a discrete-state time-dependent semi-Markov model. Probabilistic sensitivity analysis was used to characterize uncertainty around expected outcomes. Value-of-information (VOI) analysis was used to identify areas of priority for further research.

RESULTS

The cost-effectiveness estimates were highly sensitive to the estimated duration of treatment benefit. Trastuzumab remained a cost-effective treatment strategy at a willingness-to-pay threshold of £30,000 per QALY provided the duration of benefit was more than 3.6 years from treatment initiation, assuming the hazard ratio for disease-free survival was 0.63. An increasing proportion of brain metastases with trastuzumab produced a small change towards worse cost effectiveness. Long-term cardiac toxicity needed to rise to high levels to affect overall life expectancy and cost effectiveness. VOI analysis placed highest value on research into the duration of treatment benefit. The relationships between progression-free survival and overall survival and the costs of cancer recurrence were also important.

CONCLUSION

The cost effectiveness of adjuvant trastuzumab remains uncertain and dependent on assumptions regarding its clinical effect. Uncertainty around cost effectiveness could be reduced by further research into the duration of treatment effect, particularly in subgroups where this may be shorter. Long-term follow-up is warranted and methods to accurately measure duration of treatment effect and late toxicities should be developed for future adjuvant drug studies.

Budget impact analysis of trastuzumab in early breast cancer: A hospital district perspective

Objectives:Adjuvant trastuzumab is widely used in HER2-positive (HER2+) early breast cancer, and despite its cost-effectiveness, it causes substantial costs for health care. The purpose of the study was to develop a tool for estimating the budget impact of new cancer treatments. With this tool, we were able to estimate the budget impact of adjuvant trastuzumab, as well as the probability of staying within a given budget constraint.

Methods:The created model-based evaluation tool was used to explore the budget impact of trastuzumab in early breast cancer in a single Finnish hospital district with 250,000 inhabitants. The used model took into account the number of patients, HER2+ prevalence, length and cost of treatment, and the effectiveness of the therapy. Probabilistic sensitivity analysis and alternative case scenarios were performed to ensure the robustness of the results.

Results:Introduction of adjuvant trastuzumab caused substantial costs for a relatively small hospital district. In base-case analysis the 4-year net budget impact was €1.3 million. The trastuzumab acquisition costs were partially offset by the reduction in costs associated with the treatment of cancer recurrence and metastatic disease.

Conclusions:Budget impact analyses provide important information about the overall economic impact of new treatments, and thus offer complementary information to cost-effectiveness analyses. Inclusion of treatment outcomes and probabilistic sensitivity analysis provides more realistic estimates of the net budget impact. The length of trastuzumab treatment has a strong effect on the budget impact.

Looking back at 10 years of trastuzumab therapy: what is the role of HER2 testing? A systematic review of health economic analyses

Trastuzumab is a targeted therapy for human EGF receptor-2 (HER2)-positive breast cancer. The effectiveness and cost-effectiveness of trastuzumab hinges not only on its clinical efficacy in responding patients, but on the ability to accurately identify appropriate therapeutic candidates. We sought to systematically review the cost-effectiveness of trastuzumab with a focus on the impact of the test(s) used for HER2 diagnosis. Our review included 17 economic evaluations or health technology assessments of trastuzumab therapy or HER2 testing. Trastuzumab was considered cost-effective in all early-stage disease studies, while one author concluded that trastuzumab was not cost-effective for metastatic disease. Only two papers considered the joint effects of test accuracy and sequencing with trastuzumab therapy. These demonstrated that trastuzumab cost-effectiveness is sensitive to HER2-test properties.