Parameterization of a disease progression simulation model for sequentially treated metastatic human epidermal growth factor receptor 2 positive breast cancer patients

Cost-effectiveness and drug wastage of bevacizumab biosimilar with or without chemotherapy for platinum-resistant recurrent ovarian cancer

INTRODUCTION

The cost-effectiveness of adding bevacizumab biosimilar with or without chemotherapy (CT) and drug wastage in treating platinum-resistant recurrent ovarian cancer (PRrOC) was assessed.

METHODS

A three-state partitioned-survival model to compare the clinical and economic outcomes in the treatment of patients with PRrOC from a Taiwan healthcare prospective, extrapolated to two years based on data obtained from the JGOG3023 clinical trial. The primary outcomes of the model were incremental cost-effectiveness ratios (ICERs).

RESULTS

In the base-case scenario, using vials of bevacizumab biosimilar (Bevbiol) plus chemotherapy, the ICER was (new Taiwan dollar) NT$ 4,555,878 per QALY gained. The incremental cost savings of an incremental 2.02 QALYs were NT$ 1,605,828 if weight-based Bevbiol plus chemotherapy were used, but the ICER remained high at the willingness-to-pay (WTP) threshold. If the cost of Bevbiol were reduced to 50% per vial, adding it to CT would be cost-effective at an acceptable WTP threshold of NTD 2,994,200, with an ICER of NT$ 2,975,484.

CONCLUSIONS

Bevacizumab biosimilars in mg/kg dosage form with chemotherapy are still not cost-effective in Taiwan, but using weight-based dosing will reduce drug waste and save treatment costs.

Cost-effectiveness of trastuzumab biosimilar combination therapy and drug wastage as first-line treatment for HER2-positive metastatic breast cancer

Background

The rising cost of cancer drug therapy threatens the long-term sustainability of Taiwan National Health Insurance. Cost savings can be achieved through various strategies, e.g., using smaller vial sizes, sharing vials, weight-based dosing, or switching to biosimilars. Here we aimed to examine the cost-effectiveness of a trastuzumab biosimilar combined with docetaxel (TDbiol) for treatment-naïve HER2⁺ metastatic breast cancer (MBC), and the financial impact of drug wastage.

Methods

A Markov model with three health states was developed to assess the cost-effectiveness of trastuzumab biosimilars plus docetaxel over a 40-month time horizon in patients with HER2⁺ MBC. Based on the literature and our expert opinion, we assumed similar efficacy between the trastuzumab biosimilar and its reference product. The primary clinical input for the biosimilar was the same as for the reference product in the Catastrophic Patient Database (HV). Health state utilities were derived from the literature, and direct medical costs were obtained from the National Health Insurance Administration (NHIA).

Results

In the base-case scenario, the incremental cost-effectiveness ratio (ICER) was NTD 811,050 per QALY gained. One-way sensitivity analyses showed that the model was sensitive to utilities and transition probabilities, but not particularly sensitive to the wastage assumption. In scenario analyses, the ICER was higher when applying the price for trastuzumab reference biologic (branded), than for trastuzumab biosimilar.

Conclusion

The trastuzumab biosimilar combination regimen is cost-effective and offers significant drug cost savings in Taiwan.

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The conversion of biosimilar combination regimen for cancer treatment is cost-effective and cost savings compared to the reference branded drugs.

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The introduction of biosimilars and weight-based administration has resulted in significant drug cost savings, minimized drug waste, and facilitated the evaluation and/or clinical use of new therapies and drugs.

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Cancer drug waste may be considered a hidden cost to the overall cost of the cancer care setting in the past decade.

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To overcome the increasing annual healthcare expenditures, it will be essential in the near future to examine waste of high-cost target drugs, improve waste management practices, and explore cost-effective dosing regimens.

Conceptual Framework and Methodological Challenges for Modeling Effectiveness in Oncology Treatment Sequence Models

In this review, we summarize the challenges faced by existing oncology treatment sequence decision models and introduce a general framework to conceptualize such models. In the proposed framework, patients with cancer receive at least two lines of therapy (LOTs) followed by palliative care throughout their lifetime. Patients cycle through progression-free and progressive disease health states in each LOT before death. Under this framework, four broad aspects of modeling effectiveness of treatment sequences need exploration. First, disease progression, treatment discontinuation, and the relationship between the two events should be considered. Second, the effectiveness of each LOT depends on its placement in a treatment sequence as the effectiveness of later LOTs may be influenced by the earlier LOTs. Third, the treatment-free interval (TFI; time between discontinuation of earlier LOT and initiation of later LOT) may impact a therapy's effectiveness. Fourth, in the absence of head-to-head trials directly comparing LOTs, indirect treatment comparison (ITC) of outcomes for a specific LOT or even for the entire treatment sequence is important to consider. A search of decision models that estimated effectiveness of at least two lines of oncology therapy was conducted in PubMed (N = 20) and technology appraisals by the National Institute for Health and Care Excellence (N = 26) to assess four methodological aspects related to the model framework: (1) selection of outcomes for effectiveness in a treatment sequence, (2) approaches to adjust the efficacy of a treatment in consideration of its place in the sequence, (3) approaches to address TFIs between LOTs, and (4) incorporation of ITCs to estimate comparators' effectiveness in the absence of direct head-to-head evidence. Most models defined health states based on disease progression on different LOTs while estimating treatment duration outside of the main model framework (30/46) and used data from multiple data sources in different LOTs to model efficacy of a treatment sequence (41/46). No models adjusted efficacy for the characteristics of patients who switched from an earlier LOT to a later LOT or adjusted for the impact of prior therapies, and just six models considered TFIs. While 11 models applied ITC results to estimate efficacy in comparator treatment sequences, the majority limited the ITC to one LOT in the sequence. Thus, there is substantial room to improve the estimation of effectiveness for treatment sequences using existing data when comparing effectiveness of alternative treatment sequences.

Informative censoring of surrogate end-point data in phase 3 oncology trials

BACKGROUND

Kaplan-Meier (K-M) analysis, the cornerstone of cancer clinical trial interpretation, assumes that censored patients are no more or less likely to experience an event than those followed. We sought to investigate the patterns of censoring in surrogate end-points of oncology randomised controlled trials (RCTs) and examine the relationship between censoring in practice-changing treatments that failed to demonstrate survival gain.

METHODS

In this cross-sectional study of phase III RCTs published in the New England Journal of Medicine, Lancet, and JAMA, between 2010 and 2020, K-M curves of surrogate end-points with statistical significance were extracted. The reverse K-M method (i.e., events and censoring are flipped) was used to examine differential censoring using the analogous reverse hazard ratio and restricted mean survival time. Sensitivity analysis was performed by partially restoring the balance in censoring between study arms.

RESULTS

Of the 73 eligible studies with significant surrogates, 33 (45%) reported significant overall survival benefit (concordant trials), and 40 (55%) did not (discordant trials). The proportion of studies with significant differential censoring in surrogates was 43% (17/40) and 51% (17/33) in discordant and concordant trials, respectively. Trials with a significant censoring imbalance in the experimental arm occurred only in discordant trials (15% vs 0%, odds ratio [OR] = 12.62, P = 0.033), compared to excessive censoring in the control arm which occurred more in concordant trials (28% vs 52%; OR = 0.36, P = 0.036). Although censoring imbalance occurred in both groups, after sensitivity analysis, 50% of the discordant trials lost their statistical significance, compared to 15% of concordant trials (OR = 5.6, P = 0.0018).

CONCLUSION

Censoring imbalance between study arms of RCTs suggests a potential systemic bias and raises uncertainty regarding the validity of the results. Informative censoring may explain the inconsistency between therapies that seem to improve disease outcomes without concomitant survival benefit and should trigger further investigation.

Cost-effectiveness of paclitaxel, doxorubicin, cyclophosphamide and trastuzumab versus docetaxel, cisplatin and trastuzumab in new adjuvant therapy of breast cancer in china

BACKGROUND

Breast cancer is the most common cancer among women in China. Amplification of the Human epidermal growth factor receptor type 2 (HER2) gene is present and overexpressed in 18-20% of breast cancers and historically has been associated with inferior disease-related outcomes. There has been increasing interest in de-escalation of therapy for low-risk disease. This study analyzes the cost-effectiveness of Doxorubicin/ Cyclophosphamide/ Paclitaxel/ Trastuzumab (AC-TH) and Docetaxel/Carboplatin/Trastuzumab(TCH) from payer perspective over a 5 year time horizon.

METHODS

A half-cycle corrected Markov model was built to simulate the process of breast cancer events and death occurred in both AC-TH and TCH armed patients. Cost data came from studies based on a Chinese hospital. One-way sensitivity analyses as well as second-order Monte Carlo and probabilistic sensitivity analyses were performed.The transition probabilities and utilities were extracted from published literature, and deterministic sensitivity analyses were conducted.

RESULTS

We identified 41 breast cancer patients at Hangzhou First People's Hospital, among whom 15 (60%) had a partial response for AC-TH treatment and 13 (81.25%) had a partial response for TCH treatment.No cardiac toxicity was observed. Hematologic grade 3 or 4 toxicities were observed in 1 of 28 patients.Nonhematologic grade 3 or 4 toxicities with a reverse pattern were observed in 6 of 29 patients. The mean QALY gain per patient compared with TCH was 0.25 with AC-TH, while the incremental costs were $US13,142. The incremental cost-effectiveness ratio (ICER) of AC-TH versus TCH was $US 52,565 per QALY gained.

CONCLUSIONS

This study concluded that TCH neoadjuvant chemotherapy was feasible and active in HER2-overexpressing breast cancer patients in terms of the pathological complete response, complete response, and partial response rates and manageable toxicities.

A cost-effectiveness analysis of trastuzumab-containing treatment sequences for HER-2 positive metastatic breast cancer patients in Taiwan

OBJECTIVE

Treatment options for HER-2-positive metastatic breast cancer (mBC) patients have expanded markedly since trastuzumab approval in 1998. Several other regimens are now available, including pertuzumab plus trastuzumab plus docetaxel, T-DM1, capecitabine plus lapatinib, and trastuzumab plus lapatinib. This study assesses the cost-effectiveness of four treatment sequences for HER-2-positive mBC according to the Taiwanese National Health Insurance Administration (TNHIA).

METHODS

Costs (U.S. Dollars) and effectiveness (quality-adjusted life years) of four treatment sequences for HER-2-positive mBC patients were examined using a Markov model over a lifetime horizon. Transition probabilities, disease progression, and probability of adverse events and survival were derived from clinical trial data. Costs and health utilities were estimated from TNHIA, Taipei Medical University Hospital, and the literature. Deterministic, probabilistic sensitivity analyses and a scenario analysis examined parameter uncertainty and accounted for drug wastage in dosage and cost calculations.

RESULTS

Sequence 3 (1st line: trastuzumab plus docetaxel; 2nd line: T-DM1; 3rd line: trastuzumab plus lapatinib) was the most cost-effective sequence followed by sequence 1 (1st line: pertuzumab plus trastuzumab plus docetaxel; 2nd line: T-DM1; 3rd line: capecitabine plus lapatinib), and sequence 4 (1st line: trastuzumab plus docetaxel; 2nd line: trastuzumab plus lapatinib; 3rd line: trastuzumab plus capecitabine), respectively. The model was sensitive to costs and transition probabilities, but not particularly sensitive to the wastage assumption.

CONCLUSIONS

From the perspective of the TNHIA, trastuzumab plus docetaxel as 1st line followed by T-DM1 and trastuzumab plus lapatinib as 2nd and 3rd line represents the most cost-effective strategy among the four sequences considered for treating HER-2-positive mBC patients.

The promise of Immuno-oncology: implications for defining the value of cancer treatment

The rapid development of immuno-oncology (I-O) therapies for multiple types of cancer has transformed the cancer treatment landscape and brightened the long-term outlook for many patients with advanced cancer. Responding to ongoing efforts to generate value assessments for novel therapies, multiple stakeholders have been considering the question of "What makes I-O transformative?" Evaluating the distinct features and attributes of these therapies, and better characterizing how patients experience them, will inform such assessments. This paper defines ways in which treatment with I-O is different from other therapies. It also proposes key aspects and attributes of I-O therapies that should be considered in any assessment of their value and seeks to address evidence gaps in existing value frameworks given the unique properties of patient outcomes with I-O therapy. The paper concludes with a "data needs catalogue" (DNC) predicated on the belief that multiple key, unique elements that are necessary to fully characterize the value of I-O therapies are not routinely or robustly measured in current clinical practice or reimbursement databases and are infrequently captured in existing research studies. A better characterization of the benefit of I-O treatment will allow a more thorough assessment of its benefits and provide a template for the design and prioritization of future clinical trials and a roadmap for healthcare insurers to optimize coverage for patients with cancers eligible for I-O therapy.

Economic evaluation of sequencing strategies in HER2-positive metastatic breast cancer in Mexico: a contrast between public and private payer perspectives

PURPOSE

Breast cancer is the most common malignancy among women in Mexico. A large proportion of Mexican patients present with advanced disease, and 25% have HER2-positive tumors. We performed a cost-effectiveness analysis of different sequencing strategies of HER2-targeted agents in Mexico according to various payer perspectives.

METHODS

A Markov model was constructed to evaluate the cost-effectiveness of four different HER2-targeted treatment sequences among patients with HER2-positive metastatic breast cancer treated in Mexico according to three public and one private payer perspectives. Patients were followed weekly over their remaining life expectancies within the model. Health states considered were progression-free survival (PFS) 1st-3rd lines, and death. Transition probabilities between states were based on published trials. Cost data were obtained from official publications from Mexican healthcare institutions. The evaluated outcomes were PFS, OS, costs, QALYs, and incremental cost effectiveness ratio (ICER).

RESULTS

In the public payer perspective, sequences containing pertuzumab or T-DM1 were not cost-effective when compared with a sequence including the combination of trastuzumab/docetaxel as first line without subsequent T-DM1 or pertuzumab, even when utilizing alternate definitions for willingness to pay thresholds. In the private payer perspective, a sequence containing T-DM1 but not pertuzumab proved cost-effective at a lower clinical effectiveness.

CONCLUSIONS

In Mexico, the use of at least three lines of trastuzumab in combination with other therapies, but not with pertuzumab or TDM-1, represents the most cost-effective option for patients covered by the public healthcare system, and this sequence should be made available for all patients.

Reviewing the quality, health benefit and value for money of chemotherapy and targeted therapy for metastatic breast cancer

Purpose

To provide an overview of model characteristics and outcomes of model-based economic evaluations concerning chemotherapy and targeted therapy (TT) for metastatic breast cancer (MBC); to assess the quality of the studies; to analyse the association between model characteristics and study quality and outcomes.

Methods

PubMED and NHS EED were systematically searched. Inclusion criteria were as follows: English or Dutch language, model-based economic evaluation, chemotherapy or TT as intervention, population diagnosed with MBC, published between 2000 and 2014, reporting life years (LY) or quality-adjusted life-year (QALY) and an incremental cost-effectiveness ratio. General characteristics, model characteristics and outcomes of the studies were extracted. Quality of the studies was assessed through a checklist.

Results

24 studies were included, considering 50 comparisons (20 concerning chemotherapy and 30 TT). Seven comparisons were represented in multiple studies. A health state-transition model including the following health states: stable/progression-free disease, progression and death was used in 18 studies. Studies fulfilled on average 14 out of the 26 items of the quality checklist, mostly due to a lack of transparency in reporting. Thirty-one per cent of the incremental net monetary benefit was positive. TT led to higher iQALY gained, and industry-sponsored studies reported more favourable cost-effectiveness outcomes.

Conclusions

The development of a disease-specific reference model would improve the transparency and quality of model-based cost-effectiveness assessments for MBC treatments. Incremental health benefits increased over time, but were outweighed by the increased treatment costs. Consequently, increased health benefits led to lower value for money.

Electronic supplementary material

The online version of this article (doi:10.1007/s10549-017-4374-6) contains supplementary material, which is available to authorized users.

Cost-effectiveness analysis of 1st through 3rd line sequential targeted therapy in HER2-positive metastatic breast cancer in the United States

PURPOSE

Based on available phase III trial data, we performed a cost-effectiveness analysis of different treatment strategies that can be used in patients with newly diagnosed HER2-positive metastatic breast cancer (mBC).

PATIENTS AND METHODS

We constructed a Markov model to assess the cost-effectiveness of four different HER2 targeted treatment sequences in patients with HER2-positive mBC treated in the U.S. The model followed patients weekly over their remaining life expectancies. Health states considered were progression-free survival (PFS) 1st to 3rd lines, and death. Transitional probabilities were based on published phase III trials. Cost data (2015 US dollars) were captured from the U.S. Centers for Medicare and Medicaid Services (CMS) drug payment table and physician fee schedule. Health utility data were extracted from published studies. The outcomes considered were PFS, OS, costs, QALYs, the incremental cost per QALY gained ratio, and the net monetary benefit. Deterministic and probabilistic sensitivity analyses assessed the uncertainty around key model parameters and their joint impact on the base-case results.

RESULTS

The combination of trastuzumab, pertuzumab, and docetaxel (THP) as first-line therapy, trastuzumab emtansine (T-DM1) as second-line therapy, and lapatinib/capecitabine third-line resulted in 1.81 QALYs, at a cost of $335,231.35. The combination of trastuzumab/docetaxel as first line without subsequent T-DM1 or pertuzumab yielded 1.41 QALYs, at a cost of $175,240.69. The least clinically effective sequence (1.27 QALYs), but most cost-effective at a total cost of $149,250.19, was trastuzumab/docetaxel as first-line therapy, T-DM1 as second-line therapy, and trastuzumab/lapatinib as third-line therapy.

CONCLUSION

Our results suggest that THP as first-line therapy, followed by T-DM1 as second-line therapy, would require at least a 50 % reduction in the total drug acquisition cost for it to be considered a cost-effective strategy.