Valuing Chimeric Antigen Receptor T-Cell Therapy: Current Evidence, Uncertainties, and Payment Implications

Adoptive cell therapies in thoracic malignancies: a comprehensive review

This review aims to summarize recent studies and findings within adoptive cell therapies, including tumor-infiltrating lymphocytes, genetically engineered T cell receptors, and chimeric antigen receptor T cells, in the treatment of thoracic malignancies, including non-small cell lung cancer, small cell lung cancer, and malignant pleural mesothelioma. Several trials are ongoing, and a few have reported results, suggesting that adoptive cell therapies may represent a potential treatment option for these patients, especially when checkpoint inhibition has failed. We also discuss the potential implementation of these therapies, as they present a new toxicity profile and an intrinsic financial burden. Despite the challenges to overcome, such as the accurate identification of antigens and developing strategies to improve efficacy and toxicity profiles, new cellular therapies are experiencing significant development in the field of thoracic malignancies.

Economic Evaluations of Chimeric Antigen Receptor T-Cell Therapies for Hematologic and Solid Malignancies: A Systematic Review

OBJECTIVES

This study aimed to systematically review evidence on the cost-effectiveness of chimeric antigen receptor T-cell (CAR-T) therapies for patients with cancer.

METHODS

Electronic databases were searched in October 2022 and updated in September 2023. Systematic reviews, health technology assessments, and economic evaluations that compared costs and effects of CAR-T therapy in patients with cancer were included. Two reviewers independently screened studies, extracted data, synthesized results, and critically appraised studies using the Philips checklist. Cost data were presented in 2022 US dollars.

RESULTS

Our search yielded 1809 records, 47 of which were included. Most of included studies were cost-utility analysis, published between 2018 and 2023, and conducted in the United States. Tisagenlecleucel, axicabtagene ciloleucel, idecabtagene vicleucel, ciltacabtagene autoleucel, lisocabtagene maraleucel, brexucabtagene autoleucel, and relmacabtagene autoleucel were compared with various standard of care chemotherapies. The incremental cost-effectiveness ratio (ICER) for CAR-T therapies ranged from $9424 to $4 124 105 per quality-adjusted life-year (QALY) in adults and from $20 784 to $243 177 per QALY in pediatric patients. Incremental cost-effectiveness ratios were found to improve over longer time horizons or when an earlier cure point was assumed. Most studies failed to meet the Philips checklist due to a lack of head-to-head comparisons and uncertainty surrounding CAR-T costs and curative effects.

CONCLUSIONS

CAR-T therapies were more expensive and generated more QALYs than comparators, but their cost-effectiveness was uncertain and dependent on patient population, cancer type, and model assumptions. This highlights the need for more nuanced economic evaluations and continued research to better understand the value of CAR-T therapies in diverse patient populations.

A systematic review on the cost-effectiveness assessment of tisagenlecleucel for refractory or relapsing B-cell acute lymphoblastic leukemia (R/R B-ALL) treatment in children and young adults

BACKGROUND AIMS

The advanced therapy product tisagenlecleucel is a CD19-directed genetically modified autologous T-cell immunotherapy that has brought hope for children and young adults with relapsed/refractory (R/R) B-cell acute lymphoblastic leukemia (B-ALL). We sought to evaluate the cost-effectiveness of tisagenlecleucel compared with conventional salvage therapies in pediatric and young adult patients with R/R B-ALL.

METHODS

This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses parameters as registered in International Prospective Register of Systematic Reviews (CRD42021266998). Literature was searched using the MEDLINE databases via PubMed, EMBASE, Lilacs, the Cochrane Central Register of Controlled Trials and Web of Science in January 2022. Titles were screened independently by two reviewers. Articles deemed to meet the inclusion criteria were screened independently on abstract, and full texts were reviewed.

RESULTS

In total, 5627 publications were identified, from which six eligible studies were selected. The conventional therapies identified were blinatumomab (Blina), clofarabine monotherapy (Clo-M), clofarabine combined with cyclophosphamide and etoposide (Clo-C) and the combination of fludarabine, cytarabine and idarubicin (FLA-IDA). The discounted incremental cost-effectiveness ratio (ICER) per quality-adjusted life year (QALY) gained for tisagenlecleucel compared with Clo-C and Blina averages was $38 837 and $25 569, respectively. In relation to the cost of the drug, the average of tisagenlecleucel was approximately 4.3 times, 10.8 times or 4.7 times greater than the Clo-M, Clo-C and Blina, respectively.

CONCLUSIONS

This systematic review highlighted that tisagenlecleucel is a much more expensive therapy than conventional alternatives. However, tisagenlecleucel performed well on the ICER, not exceeding $100 000/QALY. It was also found that the advanced therapy product was more effective than the conventional small molecule and biological drugs, in terms of life years and QALY gained.

Capturing the Impact of Constraints on the Cost-Effectiveness of Cell and Gene Therapies: A Systematic Review

OBJECTIVE

Decision-makers need to resolve constraints on delivering cell and gene therapies to patients as these treatments move into routine care. This study aimed to investigate if, and how, constraints that affect the expected cost and health consequences of cell and gene therapies have been included in published examples of cost-effectiveness analyses (CEAs).

METHOD

A systematic review identified CEAs of cell and gene therapies. Studies were identified from previous systematic reviews and by searching Medline and Embase until 21 January 2022. Constraints described qualitatively were categorised by theme and summarised by a narrative synthesis. Constraints evaluated in quantitative scenario analyses were appraised by whether they changed the decision to recommend treatment.

RESULTS

Thirty-two CEAs of cell (n = 20) and gene therapies (n = 12) were included. Twenty-one studies described constraints qualitatively (70% cell therapy CEAs; 58% gene therapy CEAs). Qualitative constraints were categorised by four themes: single payment models; long-term affordability; delivery by providers; manufacturing capability. Thirteen studies assessed constraints quantitatively (60% cell therapy CEAs; 8% gene therapy CEAs). Two types of constraint were assessed quantitatively across four jurisdictions (USA, Canada, Singapore, The Netherlands): alternatives to single payment models (n = 9 scenario analyses); improving manufacturing (n = 12 scenario analyses). The impact on decision-making was determined by whether the estimated incremental cost-effectiveness ratios crossed a relevant cost-effectiveness threshold for each jurisdiction (outcome-based payment models: n = 25 threshold comparisons made, 28% decisions changed; improving manufacturing: n = 24 threshold comparisons made, 4% decisions changed).

CONCLUSION

The net health impact of constraints is vital evidence to help decision-makers scale up the delivery of cell and gene therapies as patient volume increases and more advanced therapy medicinal products are launched. CEAs will be essential to quantify how constraints affect the cost-effectiveness of care, prioritise constraints to be resolved, and establish the value of strategies to implement cell and gene therapies by accounting for their health opportunity cost.

Cost-effectiveness Analysis of Tisagenlecleucel Versus Blinatumomab in Children and Young Adults with Acute Lymphoblastic Leukemia: Partitioned Survival Model to Assess the Impact of an Outcome-Based Payment Arrangement

OBJECTIVE

This research assesses the impact of an outcome-based payment arrangement (OBA) linking complete remission (CR) to survival as a means of maintaining cost-effectiveness for a chimeric antigen receptor T cell (CAR-T) therapy in young patients with acute lymphoblastic leukemia (ALL).

METHODS

A partitioned survival model (PSM) was used to model the cost-effectiveness of tisagenlecleucel versus blinatumomab in ALL from the Australian healthcare system perspective. A decision tree modeled different OBAs by funneling patients into a series of PSMs based on response. Outcomes were informed by individual patient data, while costs followed Australian treatment practices. Costs and quality-adjusted life years (QALYs) were combined to calculate a single incremental cost-effectiveness ratio (ICER), reported in US dollars (2022) at a discount rate of 5% on costs and outcomes.

RESULTS

For the base case, incremental costs and benefit were $379,595 and 4.27 QALYs, giving an ICER of $88,979. The ICER was most sensitive to discount rate ($57,660-$75,081), "cure point" ($62,718-$116,206) and extrapolation method ($76,018-$94,049). OBAs had a modest effect on the ICER when response rates varied. A responder-only payment was the most effective arrangement for maintaining the ICER ($88,249-$89,434), although this option was associated with the greatest financial uncertainty. A split payment arrangement (payment on infusion followed by payment on response) reduced variability in the ICER ($82,650-$99,154) compared with a single, upfront payment ($77,599-$107,273).

CONCLUSION

OBAs had a modest impact on reducing cost-effectiveness uncertainty. The value of OBAs should be weighed against the additional resources needed to administer such arrangements, and importantly overall cost to government.

Challenges for Economic Evaluations of Advanced Therapy Medicinal Products: A Systematic Review

OBJECTIVES

Advanced therapy medicinal products (ATMPs) are drugs for human use for the treatment of chronic, degenerative, or life-threatening diseases that are based on genes, tissues, or cells. This article aimed to identify and critically review published economic analyses of ATMPs.

METHODS

A systematic review of economic analyses of ATMPs was undertaken. Study characteristics, design, sources of data, resources and unit costs, modeling and extrapolation methods, study results, and sensitivity analyses were assessed.

RESULTS

A total of 46 economic analyses of ATMP (from 45 articles) were included; 4 were cell therapy medicinal products, 33 gene therapy medicinal products, and 9 tissue-engineered products. 30 therapies had commercial marketing approval; 39 studies were cost-utility analysis, 5 were cost-effectiveness analysis, and 2 were cost only studies. Four studies predicted that the ATMP offered a step change in the management of the condition and 10 studies estimated that the ATMP would offer a lower mean cost.

CONCLUSIONS

Comparison with historical controls, pooling of data, and use of techniques such as mixture cure fraction models should be used cautiously. Sensitivity analyses should be used across a plausible range of prices. Clinical studies need to be designed to align with health technology assessment requirements, including generic quality of life, and payers should aim for clarity of criteria. Regulators and national payers should aim for compatibility of registers to allow interchange of data. Given the increasing reliance on industry-funded economic analyses, careful critical review is recommended.

Costs, effectiveness, and safety associated with Chimeric Antigen Receptor (CAR) T-cell therapy: Results from a comprehensive cancer center

Real world effectiveness, toxicity and costs analyses from chimeric antigen receptor (CAR)-T cell therapy are of utmost relevance to determine whether and how to offer patients highly personalized immunotherapy. In this study, we aimed at describing CAR T-cells effectiveness, safety and costs in a Portuguese Comprehensive Cancer Center. We performed a retrospective descriptive study of adult patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL), primary mediastinal B-cell lymphoma and transformed follicular lymphoma referred to CAR T-cell therapy, between May 2019 and February 2021. Rates of treatment response, toxicity and survival (Kaplan-Meier method) were analyzed by intention-to-treat. Direct medical costs stratified by inpatient-care, outpatient-care, and diagnostic-therapeutic procedures (DTP) were derived based on resources used and their respective unit costs. In twenty patients (median age 49.5y; 55%male; 70%DLBCL; 50% with primary refractory disease), best overall and complete response rates were 65.0% and 45.0%, respectively. Median overall (OS) and progression-free survivals were 9.2 and 7.3 months; 12-month OS rate was 42.6% (95%CI:23.2-78.3). Grade≥3 cytokine release syndrome and neurotoxicity occurred in 5.6% and 11.1% of patients, respectively. CAR T-cell therapy expenditure, including adverse events costs, was 7 176 196€, or 286 238€ when excluding drug cost. Median cost for treated patient was 355 165€ with CAR T-cell drug cost accounting for 97.0% of the overall expense. Excluding CAR T-cell acquisition cost, inpatient-care and DTP accounted for 57% and 38% of total cost/patient, respectively. Our findings highlight the heavy economic burden of CAR T-cell therapy driven by drug acquisition costs.

An Innovative PTD-IVT-mRNA Delivery Platform for CAR Immunotherapy of ErbB(+) Solid Tumor Neoplastic Cells

Chimeric antigen receptor (CAR) immunotherapy includes the genetic modification of immune cells to carry such a receptor and, thus, recognize cancer cell surface antigens. Viral transfection is currently the preferred method, but it carries the risk of off-target mutagenicity. Other transfection platforms have thus been proposed, such the in vitro transcribed (IVT)-mRNAs. In this study, we exploited our innovative, patented delivery platform to produce protein transduction domain (PTD)-IVT-mRNAs for the expression of CAR on NK-92 cells. CAR T1E-engineered NK-92 cells, harboring the sequence of T1E single-chain fragment variant (scFv) to recognize the ErbB receptor, bearing either CD28 or 4-1BB as co-stimulatory signaling domains, were prepared and assessed for their effectiveness in two different ErbB(+) cancer cell lines. Our results showed that the PTD-IVT-mRNA of CAR was safely transduced and expressed into NK-92 cells. CAR T1E-engineered NK-92 cells provoked high levels of cell death (25-33%) as effector cells against both HSC-3 (oral squamous carcinoma) and MCF-7 (breast metastatic adenocarcinoma) human cells in the co-incubation assays. In conclusion, the application of our novel PTD-IVT-mRNA delivery platform to NK-92 cells gave promising results towards future CAR immunotherapy approaches.

Price and Prejudice? The Value of Chimeric Antigen Receptor (CAR) T-Cell Therapy

Although chimeric antigen receptor (CAR) T-cell therapy has shown a high response rate in lymphoma patients, its cost-effectiveness is controversial due to the high price and uncertainty of the clinical evidence. In addition to the high acquisition cost of CAR T-cell therapy, procedure and facility cost increase the financial burden considering the frequency of adverse events such as cytokine release syndrome. In clinical research, relatively short follow-up periods were used compared to traditional cancer agents. In addition, head-to-head comparative effectiveness data are unavailable, which is an important factor when evaluating the cost-effectiveness of a new treatment. Additional evidence that will compensate for the uncertainty of existing clinical data is needed for full evaluation of long-term efficacy, safety, and comparative effectiveness.

Enhancing Health Equity Through Cancer Health Economics Research

Cancer displays some of the largest health-equity concerns of all diseases. This paper draws attention to how health economics research can assess strategies to reduce or even eliminate health disparities and provides pivotal examples of existing research as well as areas for future contributions. The paper also highlights critical data limitations that currently restrain the impact health economics research could have. We then explore new areas of inquiry where economic research is sparse but could have an important impact on health equity, particularly in topics involving Medicare and Medicaid policies that expand reimbursement and generosity of coverage. Health economics studies are notably absent from policies and practices surrounding clinical trials, representing an opportunity for future research. We urge health economics researchers to consider experiments, interventions, and assessments through primary data collection; we further encourage the formulation of multidisciplinary teams to ensure that health economics skills are well melded with other areas of expertise. These teams are needed to maximize novelty and rigor of evidence. As policies are promulgated to address disparities in cancer, involvement of economics in a multidisciplinary context can help ensure that these policies do not have unintended impacts that may deepen inequities.

Financing and Reimbursement Models for Personalised Medicine: A Systematic Review to Identify Current Models and Future Options

BACKGROUND

The number of healthcare interventions described as 'personalised medicine' (PM) is increasing rapidly. As healthcare systems struggle to decide whether to fund PM innovations, it is unclear what models for financing and reimbursement are appropriate to apply in this context.

OBJECTIVE

To review financing and reimbursement models for PM, summarise their key characteristics, and describe whether they can influence the development and uptake of PM.

METHODS

A literature review was conducted in Medline, Embase, Web of Science, and Econlit to identify studies published in English between 2009 and 2021, and reviews published before 2009. Grey literature was identified through Google Scholar, Google and subject-specific webpages. Articles that described financing and reimbursement of PM, and financing of non-PM were included. Data were extracted and synthesised narratively to report on the models, as well as facilitators, incentives, barriers and disincentives that could influence PM development and uptake.

RESULTS

One hundred and fifty-three papers were included. Research and development of PM was financed through both public and private sources and reimbursed largely through traditional models such as single fees, Diagnosis-Related Groups, and bundled payments. Financial-based reimbursement, including rebates and price-volume agreements, was mainly applied to targeted therapies. Performance-based reimbursement was identified mainly for gene and targeted therapies, and some companion diagnostics. Gene therapy manufacturers offered outcome-based rebates for treatment failure for interventions including Luxturna®, Kymriah®, Yescarta®, Zynteglo®, Zolgensma® and Strimvelis®, and coverage with evidence development for Kymriah® and Yescarta®. Targeted testing with OncotypeDX® was granted value-based reimbursement through initial coverage with evidence development. The main barriers and disincentives to PM financing and reimbursement were the lack of strong links between stakeholders and the lack of demonstrable benefit and value of PM.

CONCLUSIONS

Public-private financing agreements and performance-based reimbursement models could help facilitate the development and uptake of PM interventions with proven clinical benefit.

Bispecific Antibodies for Non-Hodgkin Lymphoma Treatment

OPINION STATEMENT

While there have been numerous advances in the field of non-Hodgkin lymphoma (NHL) over the last decade, relapsed and/or refractory (R/R) NHL remains a challenge and an area with unmet needs. T-cell redirecting immunotherapeutic approaches including chimeric antigen receptor (CAR) T-cells and bispecific antibodies (BsAbs) have the potential to revolutionize NHL therapy. BsAbs target CD3 on T-cells and CD19 or CD20 on malignant B-cells and have shown promises as a novel immunotherapy for NHL. The development of CD19 × CD3 BsAbs such as blinatumomab was met with significant challenges due to dose-limiting neurologic side effects. However, several CD20 × CD3 BsAbs including odronextamab, mosunetuzumab, glofitamab, and epcoritamab emerged recently. They have favorable toxicity profiles, with reduced cytokine release syndrome and neurotoxicity. In addition, all these BsAbs have demonstrated very promising efficacy in R/R NHL. With expansion and registrational studies actively ongoing, approvals of these agents for R/R NHL are anticipated in the near future. Some important questions pertinent to future clinical development of BsAbs include when and how to best utilize BsAbs in the management of R/R NHL, whether there is a role of BsAbs in treatment-naïve NHL, and how to combine BsAbs with other therapies. For example, whether BsAbs can be combined with cytotoxic chemotherapy effectively remains to be seen. A plethora of clinical studies will be needed to help address these questions, some of which are already ongoing. In addition, how do BsAbs compare to CAR T-cell therapy and how to choose and sequence between BsAbs and CAR T-cell therapy need to be addressed. While many of these critical questions remain to be answered in clinical studies, we believe the future of BsAbs in the NHL is very bright.

Challenges in the market access of regenerative medicines, and implications for manufacturers and decision-makers: a systematic review

Aim: Regenerative medicines (RMs) are expected to transform the treatment paradigm of rare, life-threatening diseases, while substantial challenges impede its market access. This study aimed to present these challenges. Materials & methods: Publications identified in the Medline and Embase databases until December 2020 were included. Results: Uncertainties around the relative effectiveness and long-term benefits of RMs are most scrutinized. A new reference case for RMs is questionable, but examining impacts of study perspective, time horizon, discount rate and extrapolation methods on estimates is advised. Establishing reasonable prices of RMs requires increased transparency in the development costs and better values measurements. Outcome-based payments require considerable investments and potential legislative adjustments. Conclusion: Greater flexibility for health technology assessment and economic analyses of RMs is necessary. This comprehensive review may prompt more multi-stakeholder conversations to discuss the optimized strategy for value assessment, pricing and payment in order to accelerate the market access of RMs.

A Systematic Review of Health Technology Assessments of Chimeric Antigen Receptor T-Cell Therapies in Young Compared With Older Patients

OBJECTIVES

The objective of this review was to identify sources of variability in cost-effectiveness analyses of chimeric antigen receptor T-cell (CAR-T) therapies, tisagenlecleucel and axicabtagene ciloleucel, evaluated by health technology assessment (HTA) agencies, focusing on young compared with older patients.

METHODS

HTA evaluations in pediatric acute lymphoblastic leukemia (ALL) and adult diffuse large B-cell lymphoma (DLBCL) were included from Australia, Canada, England, Norway, and the United States. Key clinical evidence, economic approach, and outcomes (costs, quality-adjusted life-years [QALYs] and incremental cost-effectiveness ratios) were summarized.

RESULTS

Fourteen HTA evaluations were identified (5 ALL, 9 DLBCL [4 tisagenlecleucel, 5 axicabtagene]). Analyses were naive comparisons of prospective single-arm studies for the CAR-Ts with retrospective cohort studies for the comparators. Key clinical evidence and economic model approaches were generally consistent by CAR-T and indication, although outcomes varied. Notably, incremental QALYs varied substantially in ALL (3.67-10.6 QALYs gained), whereas variation in DLBCL was less (1.21-1.97 [tisagenlecleucel], 1.97-3.40 [axicabtagene]). Discounting of costs and outcomes varied, with the highest QALYs generated for tisagenlecleucel in ALL (10.95) associated with the lowest discount rate (1.5%) and vice versa (4.97 QALYs; 5% discount rate). The approach to extrapolation of overall survival data varied, even where the same empirical data were used.

CONCLUSION

Modeled, long-term treatment benefit in young patients may be associated with greater uncertainty compared with adults because of potential life-long benefits with cell and gene therapies. This reflects the methodological challenges identified by HTA agencies associated with single-arm, short-term studies.

Economic Evidence on Potentially Curative Gene Therapy Products: A Systematic Literature Review

OBJECTIVE

The aim of this review was to summarize all available evidence on the cost effectiveness of potentially curative gene therapies and identify challenges that economic evaluations face in this area.

METHODS

We conducted a systematic review of four databases (PubMed/MEDLINE, Embase, CINAHL, EconLit) and grey literature sources. We conducted the search on August 23, 2019 and updated it on November 26, 2020. We included all English, French and Spanish language studies that addressed a gene therapy that had received regulatory approval or had entered a phase III trial, and also reported on costs related to the therapy. Critical appraisal was conducted to assess quality of reporting in included studies.

RESULTS

Fifty-six studies were identified. Of the 42 full economic evaluations, 71% (n = 30) evaluated chimeric antigen receptor T-cell therapies, most used either a Markov model (n = 17, 40%) and/or a partitioned survival model (n = 17, 40%), and 76% (n = 32) adopted a public or private payer perspective. The model characteristics with the greatest impact on cost effectiveness included assumptions about the efficacy of the treatment and the comparators used.

CONCLUSION

All gene therapies in this review were shown to be more effective than their comparators, although due to high costs not all were considered cost effective at standard cost-effectiveness thresholds. Despite their high cost, some gene therapies have the potential to dominate the alternatives in conditions with high mortality/disability. The choice of comparator and assumptions regarding long-term effectiveness had substantial impacts on cost-effectiveness estimates and need to be carefully considered. Both the quality of inputs and the quality of reporting were highly variable.

The impact of COVID-19 on the cell and gene therapies industry: Disruptions, opportunities, and future prospects

Coronavirus 2019 (COVID-19) has caused significant disruption to the cell and gene therapy (CGT) industry, which has historically faced substantial complexities in supply of materials, and manufacturing and logistics processes. As decision-makers shifted their priorities to COVID-19-related issues, the challenges in market authorisation, and price and reimbursement of CGTs were amplified. Nevertheless, it is encouraging to see that some CGT developers are adapting their efforts toward the development of promising COVID-19-related therapeutics and vaccines. Manufacturing resilience, digitalisation, telemedicine, value-based pricing, and innovative payment mechanisms will be increasingly harnessed to ensure that market access of CGTs is not severely disrupted.

Challenges and Clinical Strategies of CAR T-Cell Therapy for Acute Lymphoblastic Leukemia: Overview and Developments

Chimeric antigen receptor (CAR) T-cell therapy exhibits desirable and robust efficacy in patients with acute lymphoblastic leukemia (ALL). Stimulated by the revolutionized progress in the use of FDA-approved CD19 CAR T cells, novel agents with CAR designs and targets are being produced in pursuit of superior performance. However, on the path from bench to bedside, new challenges emerge. Accessibility is considered the initial barrier to the transformation of this patient-specific product into a commercially available product. To ensure infusion safety, profound comprehension of adverse events and proactive intervention are required. Additionally, resistance and relapse are the most critical and intractable issues in CAR T-cell therapy for ALL, thus precluding its further development. Understanding the limitations through up-to-date insights and characterizing multiple strategies will be critical to leverage CAR T-cell therapy flexibly for use in clinical situations. Herein, we provide an overview of the application of CAR T-cell therapy in ALL, emphasizing the main challenges and potential clinical strategies in an effort to promote a standardized set of treatment paradigms for ALL.