Cost Effectiveness of Chimeric Antigen Receptor T-Cell Therapy in Multiply Relapsed or Refractory Adult Large B-Cell Lymphoma

TCR β chain-directed bispecific antibodies for the treatment of T cell cancers

Immunotherapies such as chimeric antigen receptor (CAR) T cells and bispecific antibodies redirect healthy T cells to kill cancer cells expressing the target antigen. The pan-B cell antigen-targeting immunotherapies have been remarkably successful in treating B cell malignancies. Such therapies also result in the near-complete loss of healthy B cells, but this depletion is well tolerated by patients. Although analogous targeting of pan-T cell markers could, in theory, help control T cell cancers, the concomitant healthy T cell depletion would result in severe and unacceptable immunosuppression. Thus, therapies directed against T cell cancers require more selective targeting. Here, we describe an approach to target T cell cancers through T cell receptor (TCR) antigens. Each T cell, normal or malignant, expresses a unique TCR β chain generated from 1 of 30 TCR β chain variable gene families (TRBV1 to TRBV30). We hypothesized that bispecific antibodies targeting a single TRBV family member expressed in malignant T cells could promote killing of these cancer cells, while preserving healthy T cells that express any of the other 29 possible TRBV family members. We addressed this hypothesis by demonstrating that bispecific antibodies targeting TRBV5-5 (α-V5) or TRBV12 (α-V12) specifically lyse relevant malignant T cell lines and patient-derived T cell leukemias in vitro. Treatment with these antibodies also resulted in major tumor regressions in mouse models of human T cell cancers. This approach provides an off-the-shelf, T cell cancer selective targeting approach that preserves enough healthy T cells to maintain cellular immunity.

Diffuse Large B-Cell Lymphoma

Large B-cell lymphomas, with an estimated 150,000 new cases annually worldwide, represent almost 30% of all cases of non-Hodgkin’s lymphoma. Patients typically present with progressive lymphadenopathy, extranodal disease, or both and require therapy. Despite the advanced stage at presentation in the majority of patients, more than 60% can be cured with R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) immunochemotherapy (Fig. 1A). Patients with treatment failure after R-CHOP often have a poor outcome — in particular, those with disease that is refractory to frontline or subsequent therapies — although some patients can have a durable remission and be cured after secondary therapies. Over the past two decades, improved insights into large B-cell lymphomas, in terms of epidemiology, prognostic factors, and biologic heterogeneity, have led to a refinement of disease classification and the development of new therapeutic approaches.

Taking T-Cell Oncotherapy Off-the-Shelf

Banked allogeneic or 'off-the-shelf' (OTS) T cells from healthy human donors are being developed to address the limitations of autologous cell therapies. Potential challenges of OTS T cell therapies are associated with their allogeneic origin and the possibility of graft-versus-host disease (GvHD) and host-versus-graft immune reactions. While the risk of GvHD from OTS T cells has been proved to be manageable in clinical studies, approaches to prevent immune rejection of OTS cells are at an earlier stage of development. We provide an overview of strategies to generate OTS cell therapies and mitigate alloreactivity-associated adverse events, with a focus on recent advances for preventing immune rejection.

Cost-effectiveness of azacitidine and venetoclax in unfit patients with previously untreated acute myeloid leukemia

The phase 3 VIALE-A trial reported that venetoclax in combination with azacitidine significantly improved response rates and overall survival compared with azacitidine alone in older, unfit patients with previously untreated acute myeloid leukemia (AML). However, the cost-effectiveness of azacitidine-venetoclax in this clinical setting is unknown. In this study, we constructed a partitioned survival model to compare the cost and effectiveness of azacitidine-venetoclax with azacitidine alone in previously untreated AML. Event-free and overall survival curves for each treatment strategy were derived from the VIALE-A trial using parametric survival modeling. We calculated the incremental cost-effectiveness ratio (ICER) of azacitidine-venetoclax from a US-payer perspective. Azacitidine-venetoclax was associated with an improvement of 0.61 quality-adjusted life-years (QALYs) compared with azacitidine alone. However, the combination led to significantly higher lifetime health care costs (incremental cost, $159 595), resulting in an ICER of $260 343 per QALY gained. The price of venetoclax would need to decrease by 60% for azacitidine-venetoclax to be cost-effective at a willingness-to-pay threshold of $150 000 per QALY. These data suggest that use of azacitidine-venetoclax for previously untreated AML patients who are ineligible for intensive chemotherapy is unlikely to be cost-effective under current pricing. Significant price reduction of venetoclax would be required to reduce the ICER to a more widely acceptable value.

Use of Multi-Site Radiation Therapy for Systemic Disease Control

Metastatic cancer is a heterogeneous entity, some of which could benefit from local consolidative radiation therapy (RT). Although randomized evidence is growing in support of using RT for oligometastatic disease, a highly active area of investigation relates to whether RT could benefit patients with polymetastatic disease. This article highlights the preclinical and clinical rationale for using RT for polymetastatic disease, proposes an exploratory framework for selecting patients best suited for these types of treatments, and briefly reviews potential challenges. The goal of this hypothesis-generating review is to address personalized multimodality systemic treatment for patients with metastatic cancer. The rationale for using high-dose RT is primarily for local control and immune activation in either oligometastatic or polymetastatic disease. However, the primary application of low-dose RT is to activate distinct antitumor immune pathways and modulate the tumor stroma in efforts to better facilitate T cell infiltration. We explore clinical cases involving high- and low-dose RT to demonstrate the potential efficacy of such treatment. We then group patients by extent of disease burden to implement high- and/or low-dose RT. Patients with low-volume disease may receive high-dose RT to all sites as part of an oligometastatic paradigm. Subjects with high-volume disease (for whom standard of care remains palliative RT only) could be treated with a combination of high-dose RT to a few sites for immune activation, while receiving low-dose RT to several remaining lesions to enhance systemic responses from high-dose RT and immunotherapy. We further discuss how emerging but speculative concepts such as immune function may be integrated into this approach and examine therapies currently under investigation that may help address immune deficiencies. The review concludes by addressing challenges in using RT for polymetastatic disease, such as concerns about treatment planning workflows, treatment times, dose constraints for multiple-isocenter treatments, and economic considerations.

Health Economic Aspects of Chimeric Antigen Receptor T-cell Therapies for Hematological Cancers: Present and Future

Since 2018, 2 chimeric antigen receptor (CAR) T-cell therapies received approval from the European Medicine Agency, with list prices around 320 000 Euro (€) (EUR) per treatment. These high prices raise concerns for patient access and the sustainability of healthcare systems. We aimed to estimate the costs and budget impact associated with CAR T-cell therapies for current and future indications in hematological cancers from 2019 to 2029. We focused on the former France, Germany, Spain, Italy and the United Kingdom (EU-5) and the Netherlands. We conducted a review of list prices, health technology assessment reports, budget impact analysis dossiers, and published cost-effectiveness analyses. We forecasted the 10-year health expenditures on CAR T-cells for several hematological cancers in selected European Union countries. Nine cost-effectiveness studies were identified and list prices for CAR T-cell therapies ranged between 307 200 EUR and 350 000 EUR. Estimated additional costs for pre- and post-treatment were 50 359 EUR per patient, whereas the incremental costs of CAR T-cell therapy (when compared with care as usual) ranged between 276 086 EUR and 328 727 EUR. We estimated market entry of CAR T-cell therapies for chronic mantle cell lymphoma, follicular lymphoma, chronic lymphocytic leukemia, multiple myeloma, and acute myeloid leukemia in 2021, 2022, 2022, 2022, and 2025, respectively. Cumulative expenditure estimates for existing and future indications from 2019 to 2029 were on average 28.5 billion EUR, 32.8 billion EUR, and 28.9 billion EUR when considering CAR T-cell therapy costs only, CAR T-cell therapy costs including pre- and post-treatment, and incremental CAR T-cell therapy costs, respectively. CAR T-cell therapies seem to be promising treatment options for hematological cancers but the financial burden on healthcare systems in the former EU-5 and the Netherlands will contribute to a substantial rise in healthcare expenditure in the field of hematology.

Evaluating the Role of Novel Oncology Agents: Oncology Stewardship in Relapsed/Refractory Diffuse Large B-Cell Lymphoma

Novel treatment strategies have shifted the treatment landscape for patients with diffuse large B-cell lymphoma, particularly for those with relapsed/refractory disease. However, uncertainty remains regarding the therapeutic value of these novel agents compared to existing salvage chemotherapy regimens. In addition, the high cost associated with these agents puts both patients and health systems at risk of financial toxicity, further complicating their use. The development of clinical pathways incorporating oncology stewardship principles are necessary in order to maximize value-based care. This comprehensive review assesses the efficacy and safety data available for novel treatment options in relapsed/refractory diffuse large B-cell lymphoma and applies stewardship principles to evaluate their optimal place in therapy, with the aim of optimizing safe, effective, and financially responsible patient care.

Establishment of a cell processing laboratory to support hematopoietic stem cell transplantation and chimeric antigen receptor (CAR)-T cell therapy

Cell processing laboratories are an important part of cancer treatment centers. Cell processing laboratories began by supporting hematopoietic stem cell (HSC) transplantation programs. These laboratories adapted closed bag systems, centrifuges, sterile connecting devices and other equipment used in transfusion services/blood banks to remove red blood cells and plasma from marrow and peripheral blood stem cells products. The success of cellular cancer immunotherapies such as Chimeric Antigen Receptor (CAR) T-cells has increased the importance of cell processing laboratories. Since many of the diseases successfully treated by CAR T-cell therapy are also treated by HSC transplantation and since HSC transplantation teams are well suited to manage patients treated with CAR T-cells, many cell processing laboratories have begun to produce CAR T-cells. The methods that have been used to process HSCs have been modified for T-cell enrichment, culture, stimulation, transduction and expansion for CAR T-cell production. While processing laboratories are well suited to manufacture CAR T-cells and other cellular therapies, producing these therapies is challenging. The manufacture of cellular therapies requires specialized facilities which are costly to build and maintain. The supplies and reagents, especially vectors, can also be expensive. Finally, highly skilled staff are required. The use of automated equipment for cell production may reduce labor requirements and the cost of facilities. The steps used to produce CAR T-cells are reviewed, as well as various strategies for establishing a laboratory to manufacture these cells.

Advances in Liver Cancer Stem Cell Isolation and their Characterization

Over the last decade research on cancer stem cells (CSC) significantly contributed to a better understanding of tumor biology. Given their similarity to normal stem cells, i.e. self-renewal and pluripotency the need arises to develop robust protocols for the isolation and characterization of CSCs. As with other malignancies, hepatic tumors are composed of a heterogeneous population of cells including liver cancer stem cells (LCSC). Yet, a precise understanding of why stem cells become cancerous is still lacking. There is unmet need to develop robust protocols for the successful isolation of LCSCs from human tissue resection material as to assist in the development of molecular targeted therapies. Here we review the research progress made in the isolation and characterization of LCSCs by considering a wide range of cell surface markers and sorting methods, as applied to side populations, microsphere cultures and the gradient centrifugation method. We emphasize the different fluorescence activated cell sorting methods and the possibility to enrich LCSCs by immunomagnetic beads. We review the specificity of functional assays by considering ABCG transporter and ALDH1 enzyme activities and evaluate the in vivo tumorigenicity of LCSCs in highly sensitive bioassays. Finally, we evaluate different LCSC markers in association with viral and non-viral liver disease and explore the potential of novel drug delivery systems targeting CD133, EpCAM, CD13 and CD90 for the development of molecular targeted therapies. Graphical Abstract.

Allogeneic CAR Cell Therapy-More Than a Pipe Dream

Adoptive cellular immunotherapy using immune cells expressing chimeric antigen receptors (CARs) has shown promise, particularly for the treatment of hematological malignancies. To date, the majority of clinically evaluated CAR cell products have been derived from autologous immune cells. While this strategy can be effective it also imposes several constraints regarding logistics. This includes i) availability of center to perform leukapheresis, ii) necessity for shipment to and from processing centers, and iii) time requirements for product manufacture and clinical release testing. In addition, previous cytotoxic therapies can negatively impact the effector function of autologous immune cells, which may then affect efficacy and/or durability of resultant CAR products. The use of allogeneic CAR cell products generated using cells from healthy donors has the potential to overcome many of these limitations, including through generation of “off the shelf” products. However, allogeneic CAR cell products come with their own challenges, including potential to induce graft-versus-host-disease, as well as risk of immune-mediated rejection by the host. Here we will review promises and challenges of allogeneic CAR immunotherapies, including those being investigated in preclinical models and/or early phase clinical studies.

Cost-effectiveness and budget impact analyses of tisagenlecleucel in adult patients with relapsed or refractory diffuse large B-cell lymphoma from Singapore's private insurance payer's perspective

BACKGROUND

Patients experiencing relapsed or refractory diffuse large B-cell lymphoma (r/r DLBCL) have limited treatment options and poor prognosis. Tisagenlecleucel (TIS) has shown improved clinical outcomes, but at a high upfront cost. Singapore has a multi-payer healthcare system where private insurance is one of the major payers. This study evaluated the cost-effectiveness and budget impact of TIS against salvage chemotherapy regimen (SCR) for treating r/r DLBCL patients who have failed ≥2 lines of systemic therapy from Singapore's private insurance payer's perspective.

METHODS

Over a life-time horizon, a partitioned survival model with three health-states was developed to evaluate the cost-effectiveness of TIS vs. SCR with or without hematopoietic stem cell transplantation (HSCT). Efficacy inputs for TIS and SCR were based on 43 months of observation data from pooled JULIET and UPenn trials, and CORAL extension studies respectively. Direct costs for pre-treatment, treatment, adverse events, follow-up, subsequent-HSCT, relapse, and terminal care were included. Incremental cost-effectiveness ratios (ICERs) were calculated as the total incremental costs per quality-adjusted life-year (QALY) gained. Additionally, the financial implication of introducing TIS in Singapore from a private payer's perspective was analyzed, comparing the current treatment pathway (without TIS) with a future scenario (with TIS) over 5 years.

RESULTS

Compared with SCR, TIS was the dominant option, with cost savings of S$8,477 alongside an additional gain of 2.78 QALYs in privately insured patients who shifted from private to public hospitals for TIS treatment. Scenario analyses for patients starting in public hospitals show ICERs of S$99,623 (no subsidy) and S$133,261 (50% subsidy for SCR treatment, no subsidy for TIS), supporting the base case. The projected annual budget impact ranges from S$850,000 to S$3.4 million during the first 5 years.

CONCLUSIONS

TIS for treating r/r DLBCL patients who have failed ≥2 lines of systemic therapies, is likely to be cost effective with limited budget impact.

Cost effectiveness of axicabtagene ciloleucel versus tisagenlecleucel for adult patients with relapsed or refractory large B-cell lymphoma after two or more lines of systemic therapy in the United States

AIMS

To assess from a US payer perspective the cost-effectiveness of the chimeric antigen receptor T (CAR T)-cell therapies axicabtagene ciloleucel (axi-cel) and tisagenlecleucel (tisa-cel) to treat relapsed or refractory (r/r) large B-cell lymphoma (LBCL) following ≥2 systemic therapy lines.

METHODS

A three-state (i.e. pre-progression, post-progression, and death) partitioned survival model was used to estimate the quality-adjusted life-years (QALYs) and costs for patients on each treatment over a lifetime horizon. Progression-free survival (PFS) and overall survival (OS) were based on a matching-adjusted indirect treatment comparison (MAIC) that accounted for differences in trial population baseline characteristics. Mixture cure models (MCMs) were used to account for long-term survivors. Costs included drug acquisition and administration for the CAR T-cell therapies and conditioning chemotherapy, apheresis, CAR T-specific monitoring, transplant, hospitalization, adverse events, routine care, and terminal care. Health state utilities were derived from trial and published data. Sensitivity analyses included probabilistic sensitivity analyses (PSAs) and an analysis of extremes that assessed the results across a vast array of combinations of parametric OS and PFS curves across the two therapies.

RESULTS

Compared to tisa-cel, axi-cel resulted in 2.31 QALYs gained and a cost reduction of $1,407 in the base case. In the PSA, the cost per QALY gained was ≤$31,500 in 95% of the 1,000 simulations. In the analysis of extremes, the cost per QALY gained was ≤$7,500 in 99% of the 1,296 combinations of MCMs and ≤$40,000 in 95% of the 1,296 combinations of standard models.

LIMITATIONS

In absence of head-to-head comparative data, we relied on a MAIC, which cannot account for all possible confounders. Moreover, some outcomes (i.e. transplantations, hospitalizations, adverse events (AEs)) were not adjusted in the MAIC.

CONCLUSIONS

In this simulation, axi-cel was a superior treatment option as it is predicted to achieve better outcomes at lower or minimal incremental costs versus tisa-cel.

Chimeric antigen receptor-engineered natural killer cells for cancer immunotherapy

Natural killer (NK) cells are a critical component of the innate immune system. Chimeric antigen receptors (CARs) re-direct NK cells toward tumor cells carrying corresponding antigens, creating major opportunities in the fight against cancer. CAR NK cells have the potential for use as universal CAR cells without the need for human leukocyte antigen matching or prior exposure to tumor-associated antigens. Exciting data from recent clinical trials have renewed interest in the field of cancer immunotherapy due to the potential of CAR NK cells in the production of "off-the-shelf" anti-cancer immunotherapeutic products. Here, we provide an up-to-date comprehensive overview of the recent advancements in key areas of CAR NK cell research and identify under-investigated research areas. We summarize improvements in CAR design and structure, advantages and disadvantages of using CAR NK cells as an alternative to CAR T cell therapy, and list sources to obtain NK cells. In addition, we provide a list of tumor-associated antigens targeted by CAR NK cells and detail challenges in expanding and transducing NK cells for CAR production. We additionally discuss barriers to effective treatment and suggest solutions to improve CAR NK cell function, proliferation, persistence, therapeutic effectiveness, and safety in solid and liquid tumors.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of lymphoma

The recent development and clinical implementation of novel immunotherapies for the treatment of Hodgkin and non-Hodgkin lymphoma have improved patient outcomes across subgroups. The rapid introduction of immunotherapeutic agents into the clinic, however, has presented significant questions regarding optimal treatment scheduling around existing chemotherapy/radiation options, as well as a need for improved understanding of how to properly manage patients and recognize toxicities. To address these challenges, the Society for Immunotherapy of Cancer (SITC) convened a panel of experts in lymphoma to develop a clinical practice guideline for the education of healthcare professionals on various aspects of immunotherapeutic treatment. The panel discussed subjects including treatment scheduling, immune-related adverse events (irAEs), and the integration of immunotherapy and stem cell transplant to form recommendations to guide healthcare professionals treating patients with lymphoma.

Innate and Innate-Like Cells: The Future of Chimeric Antigen Receptor (CAR) Cell Therapy

Conventional αβ CAR-T cell-based approaches have revolutionized the field of cancer immunotherapy, but hurdles remain, especially for solid tumors. Novel strategies in conjunction with alternative cell types are therefore required for effective CAR-based therapies. In this respect, innate and innate-like cells with unique immune properties, such as natural killer (NK) cells, NKT cells, γδ T cells, and macrophages, are promising alternatives to αβ CAR-T adoptive therapy. We review the applicability of these cells in the context of CAR therapy, focusing on therapies under development, the advantages of these approaches relative to conventional CAR-T cells, and their potential in allogeneic therapies. We also discuss the inherent limitations of these cell types and approaches, and outline numerous strategies to overcome the associated obstacles.

Market access of gene therapies across Europe, USA, and Canada: challenges, trends, and solutions

This review can inform gene therapy developers on challenges that can be encountered when seeking market access. Moreover, it provides an overview of trends among challenges and potential solutions.

CAR-T TREK through the lymphoma universe, to boldly go where no other therapy has gone before

Chimeric antigen receptor (CAR) T cells (CART) therapies have changed and continue to change the treatment paradigms for B-cell malignancies because they can achieve durable complete remission in patients in whom multiple lines of treatment have failed. These unprecedented results have led to the widespread use of anti-CD19 CART therapy for patients with relapsed and refractory aggressive large B-cell lymphomas. While long-term follow-up data show that about one-third of patients achieve prolonged complete remission and are potentially cured, the majority of patients either do not respond to CD19 CART therapy or eventually relapse after CD19 CART therapy. These results are, on the one hand, driving intense research into identifying mechanisms of relapse and, on the other hand, inspiring the development of novel strategies to overcome resistance. This review summarizes current clinical outcomes of CART immunotherapy in B-cell non-Hodgkin lymphomas, describes the most up-to-date understanding of mechanisms of relapse and discusses novel strategies to address resistance to CART therapy. We are indeed at the beginning of a scientific trek to explore the mechanisms of resistance, seek out new, more effective treatment approaches based on these discoveries and to boldly go where no other therapy has gone before!

Optimized Doxorubicin Chemotherapy for Diffuse Large B-cell Lymphoma Exploits Nanocarrier Delivery to Transferrin Receptors

New treatments are needed to address persistent unmet clinical needs for diffuse large B-cell lymphoma (DLBCL). Overexpression of transferrin receptor 1 (TFR1) is common across cancer and permits cell-surface targeting of specific therapies in preclinical and clinical studies of various solid tumors. Here, we developed novel nanocarrier delivery of chemotherapy via TFR1-mediated endocytosis, assessing this target for the first time in DLBCL. Analysis of published datasets showed novel association of increased TFR1 expression with high-risk DLBCL cases. Carbon-nitride dots (CND) are emerging nanoparticles with excellent in vivo stability and distribution and are adaptable to covalent conjugation with multiple substrates. In vitro, linking doxorubicin (Dox) and transferrin (TF) to CND (CND-Dox-TF, CDT) was 10-100 times more potent than Dox against DLBCL cell lines. Gain- and loss-of-function studies and fluorescent confocal microscopy confirmed dependence of these effects on TFR1-mediated endocytosis. In contrast with previous therapeutics directly linking Dox and TF, cytotoxicity of CDT resulted from nuclear entry by Dox, promoting double-stranded DNA breaks and apoptosis. CDT proved safe to administer in vivo, and when incorporated into standard frontline chemoimmunotherapy in place of Dox, it improved overall survival by controlling patient-derived xenograft tumors with greatly reduced host toxicities. Nanocarrier-mediated Dox delivery to cell-surface TFR1, therefore, warrants optimization as a potential new therapeutic option in DLBCL. SIGNIFICANCE: Targeted nanoparticle delivery of doxorubicin chemotherapy via the TRF1 receptor presents a new opportunity against high-risk DLBCL tumors using potency and precision.

Short Time to Market and Forward Planning Will Enable Cell Therapies to Deliver R&D Pipeline Value

There is considerable industry excitement about the curative potential of cell and gene therapies, but significant challenges remain in designing cost-effective treatments that are accessible globally. We have taken a modeling-based approach to define the cost and value drivers for cell therapy assets during pharmaceutical drug development. We have created a model development program for a lentiviral modified ex vivo autologous T cell therapy for Oncology indications. Using internal and external benchmarks, we have estimated the total out-of-pocket cost of development for an Oncology cell therapy asset from target identification to filing of marketing application to be $500-600 million. Our model indicates that both clinical and Chemistry Manufacturing and Controls (CMC) cost of development for cell therapies are higher due to unique considerations of ex vivo autologous cell therapies. We have computed a threshold revenue-generating patient number for our model asset that enables selection of assets that can address high unmet medical need and generate pipeline value. Using statistical approaches, we identified that short time to market (<5 years) and reduced commercial cost of goods (<$65,000 per dose) will be essential in developing competitive assets and we propose solutions to reduce both. We emphasize that teams must proactively plan alternate development scenarios with clear articulation of path to value generation and greater patient access. We recommend using a modeling-based approach to enable data driven go/no-go decisions during multigenerational cell therapy development.

Clinical practice: chimeric antigen receptor (CAR) T cells: a major breakthrough in the battle against cancer

Chimeric antigen receptor (CAR) T cell therapy has come of age, offering a potentially curative option for patients who are refractory to standard anti-cancer treatments. The success of CAR T cell therapy in the setting of acute lymphoblastic leukemia and specific types of B cell lymphoma led to rapid regulatory approvals of CD19-directed CAR T cells, first in the United States and subsequently across the globe. Despite these major milestones in the field of immuno-oncology, growing experience with CAR T cells has also highlighted the major limitations of this strategy, namely challenges associated with manufacturing a bespoke patient-specific product, intrinsic immune cell defects leading to poor CAR T cell function as well as persistence, and/or tumor cell resistance resulting from loss or modulation of the targeted antigen. In addition, both on- and off-tumor immunotoxicities and the financial burden inherent in conventional cellular biomanufacturing often hamper the success of CAR T cell-based treatment approaches. Herein, we provide an overview of the opportunities and challenges related to the first form of gene transfer therapy to gain commercial approval in the United States. Ongoing advances in the areas of genetic engineering, precision genome editing, toxicity mitigation methods and cell manufacturing will improve the efficacy and safety of CAR T cells for hematologic malignancies and expand the use of this novel class of therapeutics to reach solid tumors.

Cost utility analysis of tisagenlecleucel vs salvage chemotherapy in the treatment of relapsed/refractory diffuse large B-cell lymphoma from Singapore's healthcare system perspective

BACKGROUND

Patients with relapsed or refractory diffuse large B-cell lymphoma (r/r DLBCL) have limited treatment options and poor prognoses. Tisagenlecleucel, a chimeric antigen receptor (CAR) T-cell therapy has shown early promise in improving survival outcomes, but at a high upfront cost. This study evaluated the cost-effectiveness of tisagenlecleucel versus salvage chemotherapy for treating patients with r/r DLBCL who have failed at least 2 lines of systemic therapies.

METHODS

A hybrid decision tree and three-state partitioned survival model (progression-free (PF), progressive disease and death) was developed from the Singapore healthcare payer perspective. Survival curves from JULIET trial and CORAL-1 extension study were extrapolated beyond trial period over a 15-year time horizon to estimate the underlying progression-free survival and overall survival parametric distributions for both arms. Health state utilities were retrieved from the literature, and direct costs were sourced from public healthcare institutions in Singapore. One-way probabilistic sensitivity analyses and scenario analyses were conducted to explore the impact of uncertainties and assumptions on cost-effectiveness results.

RESULTS

Compared with salvage chemotherapy, tisagenlecleucel was associated with a base-case incremental cost-effectiveness ratio (ICER) US$508,530 (S$686,516) per quality adjusted life year (QALY) gained and US$320,200 (S$432,269) per life year (LY) gained. One-way sensitivity analysis showed the ICER was most sensitive to time horizon, PF utility and cost of tisagenlecleucel. Scenario analyses confirmed that the ICERs remained high under favorable assumptions and substantial price reduction was required to reduce the ICER.

CONCLUSIONS

Our analysis showed tisagenlecleucel use in r/r DLBCL patients who failed at least 2 prior lines of systemic therapies was associated with exceedingly high ICER, which is unlikely to represent good use of healthcare resources. Comparative clinical evidence from the ongoing trials might provide more insight into future evaluations.

US cost-effectiveness of polatuzumab vedotin, bendamustine and rituximab in diffuse large B-cell lymphoma

Aim: To evaluate the cost-effectiveness of polatuzumab vedotin (pola) + bendamustine + rituximab (BR) in relapsed/refractory diffuse large B-cell lymphoma based on the GO29365 trial from a US payer's perspective. Materials & methods: A partitioned survival model used progression-free survival and overall survival data from the GO29365 trial. The base case analysis assumed overall survival was informed by progression-free survival; a mixture cure model estimated proportion of long-term survivors. Results: In the base case, pola + BR was cost-effective versus BR at US$35,864 per quality-adjusted life year gained. Probabilistic and one-way sensitivity analyses showed that the findings were robust. Conclusion: Pola + BR is cost-effective versus BR for the treatment of transplant-ineligible relapsed/refractory diffuse large B-cell lymphoma in the US.

Estimation of total costs in patients with relapsed or refractory diffuse large B-cell lymphoma receiving tisagenlecleucel from a US hospital's perspective

Aims: This study estimated the total costs associated with tisagenlecleucel treatment in adult patients with relapsed/refractory (r/r) diffuse large B-cell lymphoma (DLBCL) based on the JULIET trial from a United States hospital's perspective.Methods: An economic model was developed to assess the total costs associated with tisagenlecleucel treatment (from leukapheresis to two months post-infusion) in adults (aged ≥18 years) with r/r DLBCL using a fee-for-service approach. Costs were considered during the pre-treatment, tisagenlecleucel infusion, and follow-up periods, and were estimated based on the health resource utilization and safety data from the JULIET trial. Cost components included leukapheresis, lymphodepleting chemotherapy, tisagenlecleucel infusion/administration, inpatient and intensive care unit (ICU) admission, medical professional visits, lab tests/procedures, and management of adverse events (AEs). The base-case model estimated the total costs using observed hospitalization, ICU, and AE data from JULIET, while scenario analyses varied key assumptions related to AEs and hospitalization.Results: The estimated overall cost associated with tisagenlecleucel treatment from leukapheresis to two months post-infusion was $437,927/patient, of which $64,784 (14.8%) was additional to tisagenlecleucel's list price ($373,000) and the associated administration cost ($143). The top three key drivers of the additional cost were AE management ($30,594; 47.2%), inpatient/ICU not attributed to AEs ($24,285; 37.5%), and lab tests/procedures ($5,443; 8.4%). In the scenario analyses, total costs ranged from $382,702 (no AEs, no hospitalization) to $469,006 (cytokine release syndrome and B-cell aplasia, hospitalization).Limitations: This analysis was limited to two months of follow-up after tisagenlecleucel infusion, which cannot capture long-term safety outcomes associated with the treatment and may underestimate AE costs.Conclusions: The total cost of tisagenlecleucel administration from leukapheresis to two months was estimated at $437,927. In addition to tisagenlecleucel's price, the main drivers were AE management costs and inpatient/ICU costs. Future studies based on real-world, long-term use of tisagenlecleucel are warranted.

Chimeric antigen receptor T-cell therapies: Optimising the dose

Lymphocytes such as T-cells can be genetically transduced to express a synthetic chimeric antigen receptor (CAR) that re-directs their cytotoxic activity against a tumour-expressed antigen of choice. Autologous (patient-derived) CAR T-cells have been licensed to treat certain relapsed and refractory B-cell malignancies, and numerous CAR T-cell products are in clinical development. As living gene-modified cells, CAR T-cells exhibit unique pharmacokinetics, typically proliferating within the recipient during the first 14 days after administration before contracting in number, and sometimes exhibiting long-term persistence. The relationship between CAR T-cell dose and exposure is highly variable, and may be influenced by CAR design, patient immune function at the time of T-cell harvest, phenotype of the CAR T-cell product, disease burden, lymphodepleting chemotherapy and subsequent immunomodulatory therapies. Recommended CAR T-cell doses are typically established for a specific product and indication, although for some products, stratification of dose based on disease burden may mitigate toxicity while maintaining efficacy. Re-evaluation of CAR T-cell dosing may be necessary following changes to the lymphodepleting regimen, for different disease indications, and following significant manufacturing changes, if product comparability cannot be demonstrated. Dose escalation trials have typically employed 3 + 3 designs, although this approach has limitations, and alternative phase I trial designs may facilitate the identification of CAR T-cell doses that strike an optimal balance of safety, efficacy and manufacturing feasibility.

A Review of Methodological Considerations for Economic Evaluations of Gene Therapies and Their Application in Literature

OBJECTIVES

To identify methodological considerations discussed in literature addressing economic evaluations (EEs) of gene therapies (GTs). Additionally, we assessed if these considerations are applied in published GT EEs to increase understanding and explore impact.

METHODS

First a peer-reviewed literature review was performed to identify research addressing methodological considerations of GT EEs until August 2019. Identified considerations were grouped in themes using thematic content analysis. A second literature search was conducted in which we identified published evaluations. The EE quality of reporting was assessed using Consolidated Health Economic Evaluation Reporting Standards.

RESULTS

The first literature search yielded 13 articles discussing methodological considerations. The second search provided 12 EEs. Considerations identified were payment models, definition of perspectives, addressing uncertainty, data extrapolation, discount rates, novel value elements, and use of indirect and surrogate endpoints. All EEs scored satisfactory to good according to Consolidated Health Economic Evaluation Reporting Standards. Regarding methodological application, we found 1 methodological element (payment models) was applied in 2 base cases. Scenarios explored alternative perspectives, survival assumptions, and extrapolation methods in 10 EEs.

CONCLUSIONS

Although EE quality of reporting was considered good, their informativeness for health technology assessment and decision makers seemed limited owing to many uncertainties. We suggest accepted EE methods can broadly be applied to GTs, but few elements may need adjustment. Further research and multi-stakeholder consensus is needed to determine appropriateness and application of individual methodological considerations. For now, we recommend including scenario analyses to explore impact of methodological choices and (clinical) uncertainties. This study contributes to better understanding of perceived appropriate evaluation of GTs and informs best modeling practices.

Adaptive T cell immunotherapy in cancer

Impaired tumor-specific effector T cells contribute to tumor progression and unfavorable clinical outcomes. As a compensatory T cell-dependent cancer immunoediting strategy, adoptive T cell therapy (ACT) has achieved encouraging therapeutic results, and this strategy is now on the center stage of cancer treatment and research. ACT involves the ex vivo stimulation and expansion of tumor-infiltrating lymphocytes (TILs) with inherent tumor reactivity or T cells that have been genetically modified to express the cognate chimeric antigen receptor or T cell receptor (CAR/TCR), followed by the passive transfer of these cells into a lymphodepleted host. Primed T cells must provide highly efficient and long-lasting immune defense against transformed cells during ACT. Anin-depth understanding of the basic mechanisms of these living drugs can help us improve upon current strategies and design better next-generation T cell-based immunotherapies. From this perspective, we provide an overview of current developments in different ACT strategies, with a focus on frontier clinical trials that offer a proof of principle. Meanwhile, insights into the determinants of ACT are discussed, which will lead to more rational, potent and widespread applications in the future.

CAR T cells: continuation in a revolution of immunotherapy

The recent clinical successes of immunotherapy, as a result of a broader and more profound understanding of cancer immunobiology, and the leverage of this knowledge to effectively eradicate malignant cells, has revolutionised the field of cancer therapeutics. Immunotherapy is now considered the fifth pillar of cancer care, alongside surgery, chemotherapy, radiotherapy, and targeted therapy. Recently, the success of genetically modified T cells that express chimeric antigen receptors (CAR T cells) has generated considerable excitement. CAR T-cell therapy research and development has built on experience generated by laboratory research and clinical investigation of lymphokine-activated killer cells, tumour-infiltrating lymphocytes, and allogeneic haemopoietic stem-cell transplantation for cancer treatment. This Review aims to provide a background on the field of adoptive T-cell therapy and the development of genetically modified T cells, most notably CAR T-cell therapy. Many challenges exist to optimise efficacy, minimise toxicity, and broaden the application of immunotherapies based on T cells.

Next-generation CAR T cells to overcome current drawbacks

As a rapidly emerging treatment in the oncology field, adoptive transfer of autologous, genetically modified chimeric antigen receptor (CAR) T cells has shown striking efficacy and is curative in certain relapsed/refractory patients with hematologic malignancy. This treatment modality of using a "living drug" offers many tantalizing and novel therapeutic strategies for cancer patients whose remaining treatment options may have otherwise been limited. Despite the early success of CAR T cells in hematologic malignancies, many barriers remain for widespread adoption. General barriers include cellular manufacturing limitations, baseline quality of the T cells, adverse events post-infusion such as cytokine release syndrome (CRS) and neurotoxicity, and host rejection of non-human CARs. Additionally, each hematologic disease presents unique mechanisms of relapse which have to be addressed in future clinical trials if we are to augment the efficacy of CAR T treatment. In this review, we will describe current barriers to hindering efficacy of CAR T-cell treatment for hematologic malignancies in a disease-specific manner and review recent innovations aimed at enhancing the potency and applicability of CAR T cells, with the overall goal of building a framework to begin incorporating this form of therapy into the standard medical management of blood cancers.

Value and affordability of CAR T-cell therapy in the United States

In the United States the increasing number of Food and Drug Administration (FDA)-approved, innovative, and potentially effective commercial cancer therapies pose a significant financial burden on public and private payers. Chimeric antigen receptor (CAR) T cells are prototypical of this challenge. In 2017 and 2018, tisagenlecleucel (Kymriah, Novartis) and axicabtagene ciloleucel (Yescarta, Kite) were approved by the FDA for use after showing groundbreaking results in relapsed/refractory B-cell malignancies. In 2020 and 2021, four further submissions to the FDA are expected for CAR T-cell therapies for indolent and aggressive B-cell malignancies and plasma cell myeloma. Yet, with marketed prices of over $350,000 per infusion for the two FDA-approved therapies and similar price tags expected for the coming products, serious concerns are raised over value and affordability. In this review we summarize recent, peer-reviewed cost-effectiveness studies of tisagenlecleucel and axicabtagene ciloleucel in the United States; discuss key issues concerning the health plan budget impact of CAR T-cell therapy; and review policy, payment and scientific approaches that may improve the value and affordability of CAR T-cell therapy.

The Advent of CAR T-Cell Therapy for Lymphoproliferative Neoplasms: Integrating Research Into Clinical Practice

Research on CAR T cells has achieved enormous progress in recent years. After the impressive results obtained in relapsed and refractory B-cell acute lymphoblastic leukemia and aggressive B-cell lymphomas, two constructs, tisagenlecleucel and axicabtagene ciloleucel, were approved by FDA. The role of CAR T cells in the treatment of B-cell disorders, however, is rapidly evolving. Ongoing clinical trials aim at comparing CAR T cells with standard treatment options and at evaluating their efficacy earlier in the disease course. The use of CAR T cells is still limited by the risk of relevant toxicities, most commonly cytokine release syndrome and neurotoxicity, whose management has nonetheless significantly improved. Some patients do not respond or relapse after treatment, either because of poor CAR T-cell expansion, lack of anti-tumor effects or after the loss of the target antigen on tumor cells. Investigators are trying to overcome these hurdles in many ways: by testing constructs which target different and/or multiple antigens or by improving CAR T-cell structure with additional functions and synergistic molecules. Alternative cell sources including allogeneic products (off-the-shelf CAR T cells), NK cells, and T cells obtained from induced pluripotent stem cells are also considered. Several trials are exploring the curative potential of CAR T cells in other malignancies, and recent data on multiple myeloma and chronic lymphocytic leukemia are encouraging. Given the likely expansion of CAR T-cell indications and their wider availability over time, more and more highly specialized clinical centers, with dedicated clinical units, will be required. Overall, the costs of these cell therapies will also play a role in the sustainability of many health care systems. This review will focus on the major clinical trials of CAR T cells in B-cell malignancies, including those leading to the first FDA approvals, and on the new settings in which these constructs are being tested. Besides, the most promising approaches to improve CAR T-cell efficacy and early data on alternative cell sources will be reviewed. Finally, we will discuss the challenges and the opportunities that are emerging with the advent of CAR T cells into clinical routine.

Upsetting the apple CAR-T (chimeric antigen receptor T-cell therapy) - sustainability mandates USA innovation

Seldom has a medical advance in cancer therapy been as pivotal as the advent of chimeric antigen receptor (CAR)-T-cell immunotherapy. While the first applications targeted the CD19 antigen on lymphoid malignancies, the incredible specificity of these 'living drugs', curative potential and generalisability to other targets have richly justified their declaration as 2019's breakthrough of the year by Science magazine. Two CAR-T products, Yescarta (axicabtagene ciloleucel) and Kymriah (tisagenlecleucel) were Food and Drug Administration (FDA)-approved in the USA in late 2017, with the FDA commissioner Scott Gottlieb heralding 'a new frontier in medical innovation with the ability to reprogram a patient's own cells to attack a deadly cancer'. Building upon early enthusiasm, nearly 1000 cell- and gene-therapy investigational new drug applications are pending with the FDA, which expects to review and approve between 10 and 20 such treatments annually by 2025. Despite the enormous promise and urgent unmet need fulfilled by CAR-T cells, the real-world adoption of the two FDA-approved treatments has been slow.

Psychosocial care for children receiving chimeric antigen receptor (CAR) T-cell therapy

Chimeric antigen receptor (CAR) T-cell therapy has transformed the treatment of relapsed/refractory B-cell acute lymphoblastic leukemia (ALL). However, this new paradigm has introduced unique considerations specific to the patients receiving CAR T-cell therapy, including prognostic uncertainty, symptom management, and psychosocial support. With increasing availability, there is a growing need for evidence-based recommendations that address the specific psychosocial needs of the children who receive CAR T-cell therapy and their families. To guide and standardize the psychosocial care offered for patients receiving CAR T-cell therapy, we propose the following recommendations for addressing psychosocial support.

Enhancing CAR T cell efficacy: the next step toward a clinical revolution?

Introduction: The field of immunotherapy has witnessed considerable progress over the last two decades. Beginning with the ability to conceptualize CAR T cell therapy as immunotherapeutic approach, to effortlessly genetically modifying T cells, we have now reached the stage of mass production for clinical needs, all within less than quarter of a century.Areas covered: CAR T cell therapy has been tremendously successful in acute leukemia patients, specifically even in relapsed/refractory disease states. However, similar success is yet to be realized in other malignancies. This review article covers the challenges encountered with the current CD19-targeted CARs, as well as specific obstacles faced by adoptive therapy in solid tumors. It also discusses various strategies to counteract these problems.Expert opinion: CD19-directed trials in the past decade have exposed vulnerabilities in the current CAR T cell design, particularly concerning safety aspects, antigen escape, and T cell persistence. Building on these lessons and factoring in the unique challenges associated with immunotherapy in solid tumors will help generate CARs designed for future trials. Also, research related to the production of allogeneic CAR T cell products will boost the patient reach of this unique technology and possibly reduce financial burden.

The economic burden to payers of patients with diffuse large B-cell lymphoma during the treatment period by line of therapy

We retrospectively analyzed treatment patterns and healthcare costs among patients diagnosed with diffuse large B-cell lymphoma (DLBCL) during each line of therapy (LOT) using data from the IBM^® MarketScan^® Commercial and Medicare Supplemental Databases from January 2011 to May 2017. Patients were included if they had a diagnosis of DLBCL, ≥12 months of disease-free continuous enrollment prediagnosis, and ≥1 month of postdiagnosis follow-up. Of 2066 eligible patients receiving first-line treatment, 17% (n = 340) received second-line treatment; of these, 23% (n = 77) received third-line treatment. Mean healthcare expenditures (treatment duration) for first, second, and third LOTs were $111,314 (124.5 days), $88,472 (80.8 days), and $103,365 (70.9 days), respectively. When adjusted to 30-day period costs, first, second, and third LOT healthcare expenditures increased to $26,825, $32,857, and $43,854, respectively. Patients with newly diagnosed and relapsed/refractory DLBCL incur a significant cost burden (for payers), and such costs increase as patients proceed through subsequent LOTs.

CAR-T therapy and historical trends in effectiveness and cost–effectiveness of oncology treatments

Aim: This study examines how chimeric antigen receptor T-cell (CAR-T) therapy’s incremental effectiveness and cost–effectiveness profile fits into the recent history of anticancer treatments. Materials & methods: We conducted graphical and multivariable analyses using data from the Cost–Effectiveness Analysis Registry of the Tufts Medical Center and the Institute for Clinical and Economic Review’s analysis of CAR-T therapies. We collected additional information including the US FDA approval years for pharmacologic innovations. Results: CAR-T provided 5.03 (95% CI: 3.88–6.18) more incremental quality-adjusted life-years than the average pharmaceutical intervention and 4.61 (95% CI: 1.67–7.56) more than the average nonpharmaceutical intervention, while retaining similar cost–effectiveness. There was evidence of worsening cost–effectiveness by approval year for pharmaceutical interventions. Limitations: Analysis is limited to anticancer treatments studied in cost–utility analyses, estimated to cover approximately 60% of FDA-approved antineoplastic agents. Conclusion: CAR-T therapy breaks a pattern of stagnant efficacy growth in pharmaceutical innovation and demonstrates significantly greater incremental effectiveness and similar cost–effectiveness to prior innovations.

Use of CAR-Transduced Natural Killer Cells in CD19-Positive Lymphoid Tumors

BACKGROUND

Anti-CD19 chimeric antigen receptor (CAR) T-cell therapy has shown remarkable clinical efficacy in B-cell cancers. However, CAR T cells can induce substantial toxic effects, and the manufacture of the cells is complex. Natural killer (NK) cells that have been modified to express an anti-CD19 CAR have the potential to overcome these limitations.

METHODS

In this phase 1 and 2 trial, we administered HLA-mismatched anti-CD19 CAR-NK cells derived from cord blood to 11 patients with relapsed or refractory CD19-positive cancers (non-Hodgkin's lymphoma or chronic lymphocytic leukemia [CLL]). NK cells were transduced with a retroviral vector expressing genes that encode anti-CD19 CAR, interleukin-15, and inducible caspase 9 as a safety switch. The cells were expanded ex vivo and administered in a single infusion at one of three doses (1×10⁵, 1×10⁶, or 1×10⁷ CAR-NK cells per kilogram of body weight) after lymphodepleting chemotherapy.

RESULTS

The administration of CAR-NK cells was not associated with the development of cytokine release syndrome, neurotoxicity, or graft-versus-host disease, and there was no increase in the levels of inflammatory cytokines, including interleukin-6, over baseline. The maximum tolerated dose was not reached. Of the 11 patients who were treated, 8 (73%) had a response; of these patients, 7 (4 with lymphoma and 3 with CLL) had a complete remission, and 1 had remission of the Richter's transformation component but had persistent CLL. Responses were rapid and seen within 30 days after infusion at all dose levels. The infused CAR-NK cells expanded and persisted at low levels for at least 12 months.

CONCLUSIONS

Among 11 patients with relapsed or refractory CD19-positive cancers, a majority had a response to treatment with CAR-NK cells without the development of major toxic effects. (Funded by the M.D. Anderson Cancer Center CLL and Lymphoma Moonshot and the National Institutes of Health; ClinicalTrials.gov number, NCT03056339.).

'Off-the-shelf' allogeneic CAR T cells: development and challenges

Autologous chimeric antigen receptor (CAR) T cells have changed the therapeutic landscape in haematological malignancies. Nevertheless, the use of allogeneic CAR T cells from donors has many potential advantages over autologous approaches, such as the immediate availability of cryopreserved batches for patient treatment, possible standardization of the CAR-T cell product, time for multiple cell modifications, redosing or combination of CAR T cells directed against different targets, and decreased cost using an industrialized process. However, allogeneic CAR T cells may cause life-threatening graft-versus-host disease and may be rapidly eliminated by the host immune system. The development of next-generation allogeneic CAR T cells to address these issues is an active area of research. In this Review, we analyse the different sources of T cells for optimal allogeneic CAR-T cell therapy and describe the different technological approaches, mainly based on gene editing, to produce allogeneic CAR T cells with limited potential for graft-versus-host disease. These improved allogeneic CAR-T cell products will pave the way for further breakthroughs in the treatment of cancer.

Mechanisms of resistance to CAR T cell therapies

Chimeric antigen receptor (CAR)-engineered T cells have demonstrated remarkable success in the treatment of B cell malignancies. FDA approval of these therapies represents a watershed moment in the development of therapies for cancer. Despite the successes of the last decade, many patients will unfortunately not experience durable responses to CAR therapy. Emerging research has shed light on the biology responsible for these failures, and further highlighted the hurdles to broader success. Here, we review the recent research identifying how interactions between cancer cells and engineered immune cells result in resistance to CAR therapies.

Cost burden of diffuse large B-cell lymphoma

Introduction: Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma and is a clinically heterogeneous disease. Treatment pathways for DLBCL are diverse and integrate established and novel therapies.Areas covered: We review the cost burden of DLBCL and the cost-effectiveness of DLBCL management including precision and cellular medicine. We utilized Medical Subject Heading (MeSH) terms and keywords to search the National Library of Medicine online MEDLINE database (PubMed) for articles related to cost, cost burden, and cost-of-illness of DLBCL and cost-effectiveness of DLBCL management strategies published in English as of June 2019.Expert commentary: Available and developing DLBCL therapies offer improved outcomes and often curative treatment at considerable financial expense, and the total cost burden for DLBCL management is substantial for patients and the healthcare system. In the era of personalized medicine, CAR T cells and targeted therapies provide exciting avenues for current and future DLBCL care and can further increase treatment cost. Determinations of cost and cost-effectiveness in DLBCL treatment pathways should continue to guide care providers and systems in identifying cost reduction strategies to provide appropriate therapies to the greatest number of patients in treating DLBCL.