Sequential treatment approaches in the management of BRAF wild-type advanced melanoma: a cost–effectiveness analysis

Patient-level simulation models in cancer care: a systematic review

Background

Patient-level simulation (PLS) models overcome some major limitations of conventional cohort models and have broad applicability in healthcare, yet limited knowledge exists about their potential in cancer care.

Objectives

This systematic review aims to: (1) describe the application areas of PLS models in cancer care, (2) identify commonly used model structures, (3) evaluate the quality of reporting based on established guidelines, and (4) critically discuss the potential and limitations of PLS models in this context.

Methods

A systematic literature search was completed in Web of Science, PubMed, EMBASE and EconLit. Reasons underlying the use of PLS models were identified with a conventional inductive content analysis and reporting quality was assessed with an 18-item checklist based on the ISPOR-SMDM guidelines.

Results

The number of publications increased over time and most studies used state-transition microsimulation (49.25%) or discrete event simulation (48.51%). Two main application areas could be discerned, namely disease progression modelling (DPM) (78.36%) and health and care systems operation (HCSO) (21.64%). In the DPM domain, the use of PLS models was mainly motivated by the need to represent patient heterogeneity and history. In the HCSO domain, PLS models were used to better understand and improve cancer care delivery. Average reporting quality was 65.2% and did not improve over time.

Conclusion

PLS models can be used to simulate the progression of cancer and to model cancer care delivery. In the DPM domain more direct comparisons with cohort models are required to establish the relative advantages of PLS models and in the HCSO domain the impact on clinical practice needs to be systematically assessed. Furthermore, adherence to the ISPOR-SMDM guidelines should be improved.

Development of a Decision Model to Estimate the Outcomes of Treatment Sequences in Advanced Melanoma

BackgroundA decision model for patients with advanced melanoma to estimate outcomes of a wide range of treatment sequences is lacking.ObjectivesTo develop a decision model for advanced melanoma to estimate outcomes of treatment sequences in clinical practice with the aim of supporting decision making. The article focuses on methodology and long-term health benefits.MethodsA semi-Markov model with a lifetime horizon was developed. Transitions describing disease progression, time to next treatment, and mortality were estimated from real-world data (RWD) as a function of time since starting treatment or disease progression and patient characteristics. Transitions were estimated separately for melanoma with and without a BRAF mutation and for patients with favorable and intermediate prognostic factors. All transitions can be adjusted using relative effectiveness of treatments derived from a network meta-analysis of randomized controlled trials (RCTs). The duration of treatment effect can be adjusted to obtain outcomes under different assumptions.ResultsThe model distinguishes 3 lines of systemic treatment for melanoma with a BRAF mutation and 2 lines of systemic treatment for melanoma without a BRAF mutation. Life expectancy ranged from 7.8 to 12.0 years in patients with favorable prognostic factors and from 5.1 to 8.7 years in patients with intermediate prognostic factors when treated with sequences consisting of targeted therapies and immunotherapies. Scenario analyses illustrate how estimates of life expectancy depend on the duration of treatment effect.ConclusionThe model is flexible because it can accommodate different treatments and treatment sequences, and the duration of treatment effects and the transitions influenced by treatment can be adjusted. We show how using RWD and data from RCTs can harness advantages of both data sources, guiding the development of future decision models.HighlightsThe model is flexible because it can accommodate different treatments and treatment sequences, and the duration of treatment effects as well as the transitions that are influenced by treatment can be adjusted.The long-term health benefits of treatment sequences depend on the place of different therapies within a treatment sequence.Assumptions about the duration of relative treatment effects influence the estimates of long-term health benefits.We show how the use of real-world data and data from randomized controlled trials harness the advantages of both data sources, guiding the development of future decision models.

Cost-effectiveness of treatment sequences for BRAF-mutant advanced melanoma in the Netherlands using a health economic model

BACKGROUND

This study aims to evaluate the cost-effectiveness of treatment sequences for patients with advanced melanoma with a BRAF mutation in the Netherlands from a societal perspective.

METHODS

A semi-Markov model with a life-time horizon has been used to evaluate cost-effectiveness of 21 treatment sequences. Real-world data from the Dutch Melanoma Treatment Registry (DMTR) were used to estimate time to progression, next treatment and death. Utilities by health state as well as hospital costs, health care costs outside the hospital, patient and family costs and productivity costs were also derived from the DMTR. Drug costs were estimated based on the recommended dose and duration of treatment. Incremental cost-effectiveness ratios (ICERs) were presented as incremental costs per QALY gained.

RESULTS

Health benefits of treatment sequences consisting of targeted therapies and immunotherapies vary between 2.3 and 5.8 QALYs gained per patient when compared to chemotherapy. The increase in costs varies between €112,000 and €383,000. The efficiency frontier consists of nivolumab in the first line followed by ipilimumab in the second line (ICERs of €42,000/QALY and €44,000/QALY), nivolumab in the first line followed by encorafenib plus binimetinib in the second line (ICERs of €71,000/QALY and €68,000/QALY) and nivolumab plus ipilimumab in the first line followed by encorafenib plus binimetinib in the second line (ICERs of €74,000/QALY and €76,000/QALY). The first treatment given within a sequence as well as assumptions regarding treatment duration have a substantial impact on cost-effectiveness outcomes.

CONCLUSION

The ICERs can be considered cost-effective at different cost-effectiveness thresholds.

Strategies to enhance the therapeutic efficacy of anti-PD-1 antibody, anti-PD-L1 antibody and anti-CTLA-4 antibody in cancer therapy

Although immune checkpoint inhibitors (anti-PD-1 antibody, anti-PD-L1 antibody, and anti-CTLA-4 antibody) have displayed considerable success in the treatment of malignant tumors, the therapeutic effect is still unsatisfactory for a portion of patients. Therefore, it is imperative to develop strategies to enhance the effect of these ICIs. Increasing evidence strongly suggests that the key to this issue is to transform the tumor immune microenvironment from a state of no or low immune infiltration to a state of high immune infiltration and enhance the tumor cell-killing effect of T cells. Therefore, some combination strategies have been proposed and this review appraise a summary of 39 strategies aiming at enhancing the effectiveness of ICIs, which comprise combining 10 clinical approaches and 29 foundational research strategies. Moreover, this review improves the comprehensive understanding of combination therapy with ICIs and inspires novel ideas for tumor immunotherapy.

Cost-Effectiveness of Treatment Optimisation with Biomarkers for Immunotherapy in Solid Tumours: A Systematic Review

This study investigated the health economic evaluations of predictive biomarker testing in solid tumours treated with immune checkpoint inhibitors (ICIs). Searching PubMed, EMBASE, and Web of Science from June 2010 to February 2022, 58 relevant articles were reviewed out of the 730 screened. The focus was predominantly on non-small cell lung cancer (NSCLC) (65%) and other solid tumours (40%). Among the NSCLC studies, 21 out of 35 demonstrated cost-effectiveness, notably for pembrolizumab as first-line treatment when preceded by PD-L1 assessment, cost-effective at a threshold of $100,000/QALY compared to the standard of care. However, for bladder, cervical, and triple-negative breast cancers (TNBCs), no economic evaluations met the affordability threshold of $100,000/QALY. Overall, the review highlights a certain degree of uncertainty about the cost-effectiveness of ICI. In particular, we found PD-L1 expression associated with ICI treatment to be a cost-effective strategy, particularly in NSCLC, urothelial, and renal cell carcinoma. The findings suggest the potential value of predictive biomarker testing, specifically with pembrolizumab in NSCLC, while indicating challenges in achieving cost-effectiveness for certain other solid tumours.

Cost-effectiveness of immune checkpoint inhibition and targeted treatment in combination as adjuvant treatment of patient with BRAF-mutant advanced melanoma

BACKGROUND

Immune checkpoint inhibitors (ICIs) and targeted treatments have improved the health outcomes of patients with advanced melanoma. However, due to the high cost of novel therapies, it is crucial to evaluate their value by considering both effectiveness and cost. To compare the cost-effectiveness of these novel agents (atezolizumab-vemurafenib-cobimetinib, vemurafenib-plus-cobimetinib, dabrafenib-plus-trametinib, and encorafenib-plus-binimetinib) for first-line treatment of metastatic melanoma with the BRAF^V600 mutation.

METHODS

A patient-level model was developed to project the health outcomes of 4 strategies for patients with advanced melanoma. We estimated transition probabilities from the IMspire150 (ClinicalTrials.gov, NCT02908672), COMBI-AD (NCT01682083), and COLUMBUS (NCT01909453) trials using a parametric survival model. All health outcomes, including direct cost, quality-adjusted life-years (QALYs) and the incremental cost-effectiveness ratio (ICER), were estimated from the US payer perspective. Lifetime cost, QALYs, life-years (LYs), and ICERs were calculated. Univariable and probabilistic sensitivity analyses were performed to test model robustness, along with multiple scenario analyses.

RESULTS

Of the 4 competing strategies, atezolizumab-vemurafenib-cobimetinib produced the best health outcomes, and the vemurafenib-cobimetinib strategy was the least expensive option. Atezolizumab-vemurafenib-cobimetinib, dabrafenib-plus-trametinib, and vemurafenib-cobimetinib formed the cost-effective frontier, indicating that the ordered ICERs were $325,113/QALYs for dabrafenib-plus-trametinib vs. vemurafenib-cobimetinib strategies and $2,247,500/QALYs for atezolizumab-vemurafenib-cobimetinib vs. dabrafenib-plus-trametinib strategies. Encorafenib-plus-binimetinib was dominated by the other 3 competing strategies. The drug price and first-line utility significantly influenced the model utcomes.

CONCLUSIONS

For BRAF-mutant advanced melanoma, the vemurafenib-cobimetinib strategy could be considered the most cost-effective treatment at the willingness-to-pay threshold of $150,000.

Cost-Effectiveness Analysis of Sequential Treatment Strategies for Advanced Melanoma in Real Life in France

Nine drugs have been marketed for 10 years for the treatment of advanced melanoma (AM). With half of patients reaching a second line, the optimal sequence of treatments remains unclear. To inform policy-makers about their efficiency, we performed a cost-effectiveness analysis of sequential strategies in clinical practice in France, for BRAF-mutated and wild-type patients. A multistate model was developed to describe treatment sequences, associated costs, and health outcomes over 10 years. Sequences, clinical outcomes, utility scores, and economic data were extracted from the prospective Melbase cohort, collecting individual data in 1518 patients since 2013, from their AM diagnosis until their death. To adjust the differences in patients' characteristics among sequences, weighting by inverse probability was used. In the BRAF-mutated population, the MONO-targeted therapies (TT)-anti-PD1 sequence was the less expensive, whereas the anti-PD1-BI-TT sequence had an incremental cost-effectiveness ratio (ICER) of 180,441 EUR/QALY. Regarding the BRAF wild-type population, the three sequences constituted the cost-effective frontier, with ICERs ranging from 116 to 806,000 EUR/QALY. For BRAF-mutated patients, the sequence anti-PD1-BI-TT appeared to be the most efficient one in BRAF-mutated AM patients until 2018. Regarding the BRAF wild-type population until 2018, the sequence starting with IPI+NIVO appeared inefficient compared to anti-PD1, considering the extra cost for the QALY gained.

Cost-Utility of Nivolumab Plus Ipilimumab in First-Line Treatment of Advanced Melanoma in the United States: An Analysis Using Long-Term Overall Survival Data from Checkmate 067

OBJECTIVE

The aim of this study was to evaluate the cost-utility of nivolumab plus ipilimumab (NIVO + IPI) versus other first-line therapies for advanced melanoma in the United States (US) from the third-party payer perspective.

METHODS

This analysis estimated total expected life-years (LYs), quality-adjusted LYs (QALYs), and costs for first-line treatments of advanced melanoma during a 30-year time horizon using indirect treatment comparisons based on time-varying hazard ratios (HRs) and a three-state partitioned survival model. Overall survival (OS) and progression-free survival reference curves were extrapolated based on 5-year follow-up from the phase III Checkmate 067 trial (NCT01844505). Comparators of NIVO + IPI were NIVO, IPI, pembrolizumab, dabrafenib plus trametinib, encorafenib plus binimetinib (ENCO + BINI), and vemurafenib plus cobimetinib. Drug acquisition costs, treatment administration costs, follow-up time, subsequent therapy data, and adverse event frequencies were obtained from published sources. Utility weights were estimated from Checkmate 067, which compared NIVO + IPI or NIVO monotherapy with IPI monotherapy as first-line therapy in advanced melanoma. A 3% annual discount rate was applied to costs and outcomes. Sensitivity scenarios for BRAF-mutant subgroups were conducted.

RESULTS

NIVO + IPI was estimated to generate the longest OS and the highest total costs versus all comparators, accruing 6.99 LYs, 5.70 QALYs, and $469,469 over the 30-year time horizon. The incremental cost utility of NIVO + IPI versus comparators ranged from $2130 per QALY (versus ENCO + BINI) to $76,169 per QALY (versus NIVO). In all base-case and most sensitivity analyses, the incremental cost-utility ratios for NIVO + IPI were below $100,000 per QALY.

CONCLUSIONS

NIVO + IPI is estimated to be a life-extending and cost-effective treatment versus other therapies in the US, with base-case incremental cost-utility ratios below $100,000 per QALY.

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.

Cautious addition of targeted therapy to PD-1 inhibitors after initial progression of BRAF mutant metastatic melanoma on checkpoint inhibitor therapy

Background

Virtually all metastatic patients with metastatic melanoma who progress after initial treatment with PD-1 or CTLA-4 directed antibodies will die of their disease. Salvage options are urgently needed. It is theoretically attractive to combine immunotherapy with targeted agents in progressing patients with BRAF mutation positive melanoma, but the toxicity of combined treatment has proven challenging.

Methods

We performed a retrospective analysis of our patient database and identified 23 patients who progressed on initial checkpoint inhibitor treatment, who subsequently had cautious addition of BRAF±MEK inhibitor therapy to continued PD-1 antibody treatment.

Results

We found an objective response rate of 55% in second line therapy, with a median progression-free survival of 33.4 months and median overall survival of 34.1 months, with 40% of patients in unmaintained remission at over 3 years. Ten of 12 responding patients were able to discontinue all therapy and continue in unmaintained remission. Toxicity of this approach was generally manageable (21.7% grade 3–5 toxicity). There was 1 early sudden death for unknown reasons in a responding patient.

Discussion

Our results suggest that 2nd line therapy with PD-1 inhibitors plus BRAF±MEK inhibitors has substantial activity and manageable toxicity. This treatment can induce additional durable complete responses in patients who have progressed on initial immunotherapy. These results suggest further evaluation be performed of sequential PD-1 antibody treatment with cautious addition of targeted therapy in appropriate patients.

Systemic Therapy for Melanoma: ASCO Guideline

PURPOSE

To provide guidance to clinicians regarding the use of systemic therapy for melanoma.

METHODS

ASCO convened an Expert Panel and conducted a systematic review of the literature.

RESULTS

A systematic review, one meta-analysis, and 34 additional randomized trials were identified. The published studies included a wide range of systemic therapies in cutaneous and noncutaneous melanoma.

RECOMMENDATIONS

In the adjuvant setting, nivolumab or pembrolizumab should be offered to patients with resected stage IIIA/B/C/D BRAF wild-type cutaneous melanoma, while either of those two agents or the combination of dabrafenib and trametinib should be offered in BRAF-mutant disease. No recommendation could be made for or against the use of neoadjuvant therapy in cutaneous melanoma. In the unresectable/metastatic setting, ipilimumab plus nivolumab, nivolumab alone, or pembrolizumab alone should be offered to patients with BRAF wild-type cutaneous melanoma, while those three regimens or combination BRAF/MEK inhibitor therapy with dabrafenib/trametinib, encorafenib/binimetinib, or vemurafenib/cobimetinib should be offered in BRAF-mutant disease. Patients with mucosal melanoma may be offered the same therapies recommended for cutaneous melanoma. No recommendation could be made for or against specific therapy for uveal melanoma. Additional information is available at www.asco.org/melanoma-guidelines.

Economic evaluations of cancer immunotherapy: a systematic review and quality evaluation

OBJECTIVES

Scientific advances in the last decade have highlighted the use of immunotherapy, especially immune checkpoint inhibitors, to be an effective strategy in cancer therapy. However, these immunotherapeutic agents are expensive, and their use must take into account economic criteria. Thus, the objective of the present study was to systematically identify and review published EE related to the use of ipilimumab, nivolumab or pembrolizumab in melanoma, lung cancer, head and neck cancer or renal cell carcinoma, and to assess their quality.

METHODS

The systematic literature research was conducted on Medline via PubMed and the Cochrane Central Register of Controlled Trials to identify economic evaluations published before July 2018. The quality of each selected economic evaluation was assessed by two independent reviewers using the Drummond checklist.

RESULTS

Our systematic review was based on 32 economic evaluations using different methodological approaches, different perspectives and different time horizons. Three-quarters of the economic evaluations are full (n = 24) with a Drummond score ≥ 7, synonymous of "high quality". Among them, 66% reported a strategy that was cost-effective. The most assessed immunotherapeutic agent was nivolumab. In patients with renal cell carcinoma or head and neck cancer, it was less likely to be cost-effective than in patients with melanoma or lung cancer.

CONCLUSIONS

Whether or not these findings will be confirmed remains to be seen when market approval to cover more indications is extended and new effective immunotherapeutic agents become available.

Cost-Utility Analysis of Nivolumab in Adjuvant Treatment of Melanoma in France

Introduction

The aim of the current study is to estimate the cost-effectiveness of adjuvant treatment with nivolumab relative to clinically relevant comparators in adult patients with melanoma with lymph node involvement or metastatic disease who have undergone complete resection from a French societal perspective.

Methods

The comparators were observation, low-dose interferon and pembrolizumab. A subgroup analysis was carried out in patients with BRAF mutation, adding dabrafenib plus trametinib. A three-state partitioned survival model was developed to project costs and health benefits over a 20-year time horizon. Extrapolation for recurrence-free survival (RFS) and overall survival (OS) was carried out using spline-based models. Because of the immaturity of OS data in pivotal trials for nivolumab and pembrolizumab, a predictive model of OS treatment effect based on RFS effect was developed using a correlation equation. Health state utilities and adverse events disutilities were derived from the CheckMate 238 trial and literature. Costs were estimated in 2019 euros. The model’s primary outcome was efficiency frontier. Deterministic and probabilistic sensitivity analyses were conducted to assess the robustness of results.

Results

Observation, low-dose interferon and nivolumab were on the efficiency frontier. The incremental cost–utility ratio of nivolumab versus low-dose interferon (closest therapy on the efficiency frontier) was €37,886/quality-adjusted life year (QALY). Probabilistic sensitivity analysis reported an 80% probability of nivolumab being a cost-effective strategy for a willingness-to-pay threshold of €52,000/QALY. In the subgroup with BRAF mutation, the efficiency frontier was not changed by the addition of dabrafenib plus trametinib.

Conclusions

Nivolumab is a cost-effective strategy as adjuvant treatment in adult patients with surgically resected melanoma in France.

Electronic supplementary material

The online version of this article (10.1007/s13555-020-00446-z) contains supplementary material, which is available to authorized users.

HSP27 Expression as a Novel Predictive Biomarker for Bevacizumab: is it Cost Effective?

BACKGROUND

Despite the extensive use of bevacizumab in a range of oncology indications, the US FDA revoked its approval for breast cancers, and multiple negative trials in several solid malignancies have been reported, so the need for predictive biomarkers has increased. The development of predictive biomarkers for anti-angiogenic bevacizumab therapy has long been pursued but without success.

INTRODUCTION

Heat shock protein (HSP)-27 expression has recently been identified as a predictive biomarker for bevacizumab in treating metastatic melanoma. This study aimed to evaluate the cost effectiveness of HSP27 biomarker testing before administration of bevacizumab.

METHODS

A partitioned survival analysis model with three mutually exclusive health states (progression-free survival, progressed disease, and death) was developed using a Norwegian health system perspective. The proportion of patients in each state was calculated using the area under the Kaplan-Meier curve for progression-free and overall survival derived from trials of bevacizumab and dacarbazine. Three strategies were compared: (1) test-treat with HSP27 biomarker and bevacizumab, (2) treat-all with dacarbazine without HSP27 testing, (3) treat-all with bevacizumab without HSP27 testing. Quality-adjusted life-years (QALYs) and costs were calculated for each strategy and discounted at 4%. A lifetime horizon was applied. Uncertainty analyses were performed. Expected value of perfect information (EVPI) was estimated to assess the potential value of further research to generate more evidence.

RESULTS

Although the test-treat strategy was cost effective compared with treat-all with dacarbazine, it was not cost effective compared with treat-all with bevacizumab without HSP27 testing. However, EVPI results showed very minimal or no value in conducting further research efforts to reduce uncertainties around current information.

CONCLUSION

The results of this study suggested that testing for HSP27 expression before administering bevacizumab is not cost effective compared with treat-all with bevacizumab without testing. It indicates that HSP27 expression is not cost effective as a potential predictive biomarker for bevacizumab. This may not necessarily mean that HSP27 is a bad biomarker for bevacizumab, but it may mean that bevacizumab is much better than dacarbazine regardless of HSP27 expression, so patient stratification according to HSP27 status is meaningless. Or, indeed, it may imply that HSP27 is not sufficiently good at identifying the right patients for bevacizumab.

Therapy preferences in melanoma treatment-Willingness to pay and preference of quality versus length of life of patients, physicians, healthy individuals and physicians with oncological disease

Background

In recent years, monoclonal antibodies such as ipilimumab, nivolumab, and pembrolizumab have made a significant impact on the treatment of advanced melanoma. Combination of immune checkpoint inhibitors leads to improved survival and response rates of 58%‐61% as compared to monotherapy (36%‐44%). However, the price for the better response rates is also a higher frequency of severe adverse events (59%) as compared to monotherapy (17%‐21%). This study examines attitudes towards melanoma therapy options of physicians, healthy individuals, melanoma patients, and physicians with oncological disease, their willingness to pay, and preference of quality versus length of life.

Methods

After obtaining ethical approval and informed consent surveys were conducted in 111 participants divided into four groups: melanoma patients (n = 30), healthy individuals as controls (n = 30), physicians (n = 27), and physicians with oncological disease (n = 24). Statistical analyses were conducted using SPSS statistics (version 25, IBM), applying the Pearson´s chi‐squared test, Spearman correlation coefficient, Wilcoxon‐Mann‐Whitney test, and Kruskal‐Wallis test.

Results

Life prolongation is more valued by melanoma patients and physicians with oncological disease compared to healthy controls and healthy physicians. In total, 30% of melanoma patients opt for a life prolonging therapy in all cases, even if this life prolongation is only marginal. Physicians are the strongest proponents of combination immunotherapy.   

Conclusion

The valuation of the different treatment options differs in the four study groups with affected people valuing life prolongation much more. The individual value of cancer therapies is high, but differs from the societal standpoint.

How to Address Uncertainty in Health Economic Discrete-Event Simulation Models: An Illustration for Chronic Obstructive Pulmonary Disease

Background. Evaluation of personalized treatment options requires health economic models that include multiple patient characteristics. Patient-level discrete-event simulation (DES) models are deemed appropriate because of their ability to simulate a variety of characteristics and treatment pathways. However, DES models are scarce in the literature, and details about their methods are often missing. Methods. We describe 4 challenges associated with modeling heterogeneity and structural, stochastic, and parameter uncertainty that can be encountered during the development of DES models. We explain why these are important and how to correctly implement them. To illustrate the impact of the modeling choices discussed, we use (results of) a model for chronic obstructive pulmonary disease (COPD) as a case study. Results. The results from the case study showed that, under a correct implementation of the uncertainty in the model, a hypothetical intervention can be deemed as cost-effective. The consequences of incorrect modeling uncertainty included an increase in the incremental cost-effectiveness ratio ranging from 50% to almost a factor of 14, an extended life expectancy of approximately 1.4 years, and an enormously increased uncertainty around the model outcomes. Thus, modeling uncertainty incorrectly can have substantial implications for decision making. Conclusions. This article provides guidance on the implementation of uncertainty in DES models and improves the transparency of reporting uncertainty methods. The COPD case study illustrates the issues described in the article and helps understanding them better. The model R code shows how the uncertainty was implemented. For readers not familiar with R, the model's pseudo-code can be used to understand how the model works. By doing this, we can help other developers, who are likely to face similar challenges to those described here.

Addressing Challenges of Economic Evaluation in Precision Medicine Using Dynamic Simulation Modeling

OBJECTIVES

The objective of this article is to describe the unique challenges and present potential solutions and approaches for economic evaluations of precision medicine (PM) interventions using simulation modeling methods.

METHODS

Given the large and growing number of PM interventions and applications, methods are needed for economic evaluation of PM that can handle the complexity of cascading decisions and patient-specific heterogeneity reflected in the myriad testing and treatment pathways. Traditional approaches (eg, Markov models) have limitations, and other modeling techniques may be required to overcome these challenges. Dynamic simulation models, such as discrete event simulation and agent-based models, are used to design and develop mathematical representations of complex systems and intervention scenarios to evaluate the consequence of interventions over time from a systems perspective.

RESULTS

Some of the methodological challenges of modeling PM can be addressed using dynamic simulation models. For example, issues regarding companion diagnostics, combining and sequencing of tests, and diagnostic performance of tests can be addressed by capturing patient-specific pathways in the context of care delivery. Issues regarding patient heterogeneity can be addressed by using patient-level simulation models.

CONCLUSION

The economic evaluation of PM interventions poses unique methodological challenges that might require new solutions. Simulation models are well suited for economic evaluation in PM because they enable patient-level analyses and can capture the dynamics of interventions in complex systems specific to the context of healthcare service delivery.

Five-Year Survival with Combined Nivolumab and Ipilimumab in Advanced Melanoma

BACKGROUND

Nivolumab plus ipilimumab or nivolumab alone resulted in longer progression-free and overall survival than ipilimumab alone in a trial involving patients with advanced melanoma. We now report 5-year outcomes in the trial.

METHODS

We randomly assigned patients with previously untreated advanced melanoma to receive one of the following regimens: nivolumab (at a dose of 1 mg per kilogram of body weight) plus ipilimumab (3 mg per kilogram) every 3 weeks for four doses, followed by nivolumab (3 mg per kilogram every 2 weeks); nivolumab (3 mg per kilogram every 2 weeks) plus ipilimumab-matched placebo; or ipilimumab (3 mg per kilogram every 3 weeks for four doses) plus nivolumab-matched placebo. The two primary end points were progression-free survival and overall survival in the nivolumab-plus-ipilimumab group and in the nivolumab group, as compared with the ipilimumab group.

RESULTS

At a minimum follow-up of 60 months, the median overall survival was more than 60.0 months (median not reached) in the nivolumab-plus-ipilimumab group and 36.9 months in the nivolumab group, as compared with 19.9 months in the ipilimumab group (hazard ratio for death with nivolumab plus ipilimumab vs. ipilimumab, 0.52; hazard ratio for death with nivolumab vs. ipilimumab, 0.63). Overall survival at 5 years was 52% in the nivolumab-plus-ipilimumab group and 44% in the nivolumab group, as compared with 26% in the ipilimumab group. No sustained deterioration of health-related quality of life was observed during or after treatment with nivolumab plus ipilimumab or with nivolumab alone. No new late toxic effects were noted.

CONCLUSIONS

Among patients with advanced melanoma, sustained long-term overall survival at 5 years was observed in a greater percentage of patients who received nivolumab plus ipilimumab or nivolumab alone than in those who received ipilimumab alone, with no apparent loss of quality of life in the patients who received regimens containing nivolumab. (Funded by Bristol-Myers Squibb and others; CheckMate 067 ClinicalTrials.gov number, NCT01844505.).

Treatment-Free Survival: A Novel Outcome Measure of the Effects of Immune Checkpoint Inhibition-A Pooled Analysis of Patients With Advanced Melanoma

PURPOSE

Outcome measures that comprehensively capture attributes of immuno-oncology agents, including prolonged treatment-free time and persistent treatment-related adverse events (TRAEs), are needed to complement conventional survival end points.

METHODS

We pooled data from the CheckMate 067 and 069 clinical trials of nivolumab and ipilimumab, as monotherapies or in combination, for patients with advanced melanoma. Treatment-free survival (TFS) was defined as the area between Kaplan-Meier curves for two conventional time-to-event end points, each defined from random assignment: time to immune checkpoint inhibitor (ICI) protocol therapy cessation and time to subsequent systemic therapy initiation or death. TFS was partitioned as time with and without toxicity by a third end point, time to cessation of both ICI therapy and toxicity. Toxicity included persistent and late-onset grade 3 or higher TRAEs. The area under each Kaplan-Meier curve was estimated by the 36-month restricted mean time.

RESULTS

At 36 months, many of the 1,077 patients who initiated ICI therapy were surviving free of subsequent therapy initiation (47% nivolumab plus ipilimumab, 37% nivolumab, 15% ipilimumab). The restricted mean TFS was longer for nivolumab plus ipilimumab (11.1 months) compared with nivolumab (4.6 months; difference, 6.5 months; 95% CI, 5.0 to 8.0 months) or ipilimumab (8.7 months; difference, 2.4 months; 95% CI, 0.8 to 4.1 months); restricted mean TFS represented 31% (3% with and 28% without toxicity), 13% (1% and 11%), and 24% (less than 1% and 23%) of the 36-month period, respectively, in the three treatment groups. TFS without toxicity was longer for nivolumab plus ipilimumab than nivolumab (difference, 6.0 months) or ipilimumab (difference, 1.7 months).

CONCLUSION

The analysis of TFS between ICI cessation and subsequent therapy initiation revealed longer TFS without toxicity for patients with advanced melanoma who received nivolumab plus ipilimumab compared with nivolumab or ipilimumab. Regardless of treatment, a small proportion of the TFS involved grade 3 or higher TRAEs.

Healthcare cost comparison analysis of nivolumab in combination with ipilimumab versus nivolumab monotherapy and ipilimumab monotherapy in advanced melanoma

Background

Monoclonal antibodies targeting the cytotoxic T-lymphocyte-associated antigen 4 (CTLA4) (e.g., ipilimumab [IPI]) and the programmed cell death-1 (PD1) receptor (e.g., nivolumab [NIVO]) represent significant breakthroughs in the treatment of advanced melanoma. A combination of the 2 agents has demonstrated efficacy and survival benefits over NIVO or IPI monotherapy in treating advanced melanoma. We compared melanoma-specific costs following treatment with NIVO + IPI, NIVO monotherapy, or IPI monotherapy from the UK and German perspectives to ascertain whether these clinical benefits resulted in a cost advantage.

Methods

Patient-level resource utilization data for the three treatment cohorts were obtained from the CheckMate 067 trial (NCT01844505). All melanoma-specific resources, including drugs (index, concomitant and subsequent melanoma medications), office visits, emergency room visits, hospitalizations, lab tests, procedures and surgeries, utilized over a 48-month evaluation period after start of index treatment were included. Unit costs specific to each geography were applied from external sources. Mean costs per surviving patients were calculated for each successive 30-day period from treatment start and aggregated over the evaluation period.

Results

The total per-patient costs incurred by advanced melanoma patients over the 48-month period following treatment initiation with NIVO + IPI were 9% lower than NIVO monotherapy (£226k vs £248k) and 3% lower compared to IPI monotherapy (£226k vs. £233k) in the UK. In Germany, the total costs incurred by NIVO + IPI cohort were 5% lower than NIVO monotherapy (€258k vs €271k) and 4% lower compared to IPI monotherapy (€258k vs. €268k). Drug costs accounted for > 85% of total costs. Non-drug costs were slightly higher for NIVO + IPI and IPI monotherapy because of higher hospitalization rates. Costs incurred on subsequent drugs post progression were about 45% and 65% lower in NIVO + IPI cohort compared with NIVO and IPI monotherapy cohorts respectively.

Conclusions

The total costs incurred by a patient over a 48-month period following treatment initiation with NIVO + IPI are lower when compared with patients initiating monotherapies; further, the cost advantage is seen to be increasing over time. The clinical benefits offered by the regimen are thus supplemented by a cost advantage, as patients receiving either monotherapy treatment experience faster progression and, consequently, higher subsequent treatment costs. (Note: The cost results reported here are specific to the UK, and Germany, and may not be generalizable to other geographies).

Electronic supplementary material

The online version of this article (10.1186/s40164-019-0138-9) contains supplementary material, which is available to authorized users.

Association of Baseline Serum Levels of CXCL5 With the Efficacy of Nivolumab in Advanced Melanoma

Anti-programmed cell death protein 1 (PD1) antibodies are in wide use for the treatment of various cancers. PD1 antibody-based immunotherapy, co-administration of nivolumab and ipilimumab, is one of the optimal immunotherapies, especially in advanced melanoma with high tumor mutation burden. Since this combined therapy leads to a high frequency of serious immune-related adverse events (irAEs) in patients with advanced melanoma, biomarkers are needed to evaluate nivolumab efficacy to avoid serious irAEs caused by ipilimumab. This study analyzed baseline serum levels of CXCL5, CXCL10, and CCL22 in 46 cases of advanced cutaneous melanoma treated with nivolumab. Baseline serum levels of CXCL5 were significantly higher in responders than in non-responders. In contrast, there were no significant differences in baseline serum levels of CXCL10 and CCL22 between responders and non-responders. These results suggest that baseline serum levels of CXCL5 may be useful as a biomarker for identifying patients with advanced cutaneous melanoma most likely to benefit from anti-melanoma immunotherapy.

Clinical and economic outcomes associated with treatment sequences in patients with BRAF-mutant advanced melanoma

AIM

The cost-effectiveness of treatment sequences in BRAF-mutant advanced melanoma.

MATERIALS & METHODS

A discrete event simulation model was developed to estimate total costs and health outcomes over a patient's lifetime (30 years). Efficacy was based on the CheckMate 067/069 trials and a matching-adjusted-indirect comparison between immuno-oncology and targeted therapies. Safety, cost (in US dollars; US third-party payer perspective) and health-related quality-of-life inputs were based on published literature.

RESULTS

Estimated survival gain was higher for sequences initiating with anti-PD-1 + anti-CTLA-4 than for anti-PD-1 monotherapy or BRAF+MEK inhibitors. The incremental cost-effectiveness ratio per QALY gained for first-line anti-PD-1 + anti-CTLA-4 was US$54,273 versus first-line anti-PD-1 and $79,124 versus first-line BRAF+MEK inhibitors.

CONCLUSION

Initiating treatment with anti-PD-1 + anti-CTLA-4 was more cost-effective than initiation with anti-PD-1 monotherapy or BRAF+MEK inhibitors.