Recent Progress and Future Perspectives of Immunotherapy in Advanced Gastric Cancer

As one of the most common forms of solid tumours, gastric carcinoma has been revealed as the third leading cause of death worldwide. The symptom of gastric cancer is usually not obvious and thus difficult to detect at earlier stages. Therefore, gastric cancer is already in the advanced stage once detected in patients, which has a poor prognosis due to ineffective therapies and multiple resistance. Recent advance in understanding the microenvironment of cancer has significantly promoted the development of immunotherapy for advanced gastric cancer. Immunotherapy can induce immune responses in gastric cancer patients thus leads to the destruction of cancer cells. In comparison of traditional therapy, immunotherapy has demonstrated robust efficacy and tolerable toxicity. Therefore, this novel strategy for treatment of advanced gastric cancer has gain increasingly popularity. In this review, we summarize recent progress of immunotherapy in advanced gastric cancer, such as immune check point inhibitors, adoptive cell therapy, VEGF inhibitors, cancer vaccines and CAR-T cell therapy. We highlight immunotherapies involved in clinical applications and discuss the existing challenges of current immunotherapies and promising strategies to overcome these limitations.

Recent Progress and Future Perspectives of Immunotherapy in Advanced Gastric Cancer

As one of the most common forms of solid tumours, gastric carcinoma has been revealed as the third leading cause of death worldwide. The symptom of gastric cancer is usually not obvious and thus difficult to detect at earlier stages. Therefore, gastric cancer is already in the advanced stage once detected in patients, which has a poor prognosis due to ineffective therapies and multiple resistance. Recent advance in understanding the microenvironment of cancer has significantly promoted the development of immunotherapy for advanced gastric cancer. Immunotherapy can induce immune responses in gastric cancer patients thus leads to the destruction of cancer cells. In comparison of traditional therapy, immunotherapy has demonstrated robust efficacy and tolerable toxicity. Therefore, this novel strategy for treatment of advanced gastric cancer has gain increasingly popularity. In this review, we summarize recent progress of immunotherapy in advanced gastric cancer, such as immune check point inhibitors, adoptive cell therapy, VEGF inhibitors, cancer vaccines and CAR-T cell therapy. We highlight immunotherapies involved in clinical applications and discuss the existing challenges of current immunotherapies and promising strategies to overcome these limitations.

Recent Progress and Future Perspectives of Immunotherapy in Advanced Gastric Cancer

As one of the most common forms of solid tumours, gastric carcinoma has been revealed as the third leading cause of death worldwide. The symptom of gastric cancer is usually not obvious and thus difficult to detect at earlier stages. Therefore, gastric cancer is already in the advanced stage once detected in patients, which has a poor prognosis due to ineffective therapies and multiple resistance. Recent advance in understanding the microenvironment of cancer has significantly promoted the development of immunotherapy for advanced gastric cancer. Immunotherapy can induce immune responses in gastric cancer patients thus leads to the destruction of cancer cells. In comparison of traditional therapy, immunotherapy has demonstrated robust efficacy and tolerable toxicity. Therefore, this novel strategy for treatment of advanced gastric cancer has gain increasingly popularity. In this review, we summarize recent progress of immunotherapy in advanced gastric cancer, such as immune check point inhibitors, adoptive cell therapy, VEGF inhibitors, cancer vaccines and CAR-T cell therapy. We highlight immunotherapies involved in clinical applications and discuss the existing challenges of current immunotherapies and promising strategies to overcome these limitations.

Inducible localized delivery of an anti-PD-1 scFv enhances anti-tumor activity of ROR1 CAR-T cells in TNBC

Background

Chimeric antigen receptor (CAR)-T cells can induce powerful immune responses in patients with hematological malignancies but have had limited success against solid tumors. This is in part due to the immunosuppressive tumor microenvironment (TME) which limits the activity of tumor-infiltrating lymphocytes (TILs) including CAR-T cells. We have developed a next-generation armored CAR (F i-CAR) targeting receptor tyrosine kinase-like orphan receptor 1 (ROR1), which is expressed at high levels in a range of aggressive tumors including poorly prognostic triple-negative breast cancer (TNBC). The F i-CAR-T is designed to release an anti-PD-1 checkpoint inhibitor upon CAR-T cell activation within the TME, facilitating activation of CAR-T cells and TILs while limiting toxicity.

Methods

To bolster potency, we developed a F i-CAR construct capable of IL-2-mediated, NFAT-induced secretion of anti-PD-1 single-chain variable fragments (scFv) within the tumor microenvironment, following ROR1-mediated activation. Cytotoxic responses against TNBC cell lines as well as levels and binding functionality of released payload were analyzed in vitro by ELISA and flow cytometry. In vivo assessment of potency of F i-CAR-T cells was performed in a TNBC NSG mouse model.

Results

F i-CAR-T cells released measurable levels of anti-PD-1 payload with 5 h of binding to ROR1 on tumor and enhanced the cytotoxic effects at challenging 1:10 E:T ratios. Treatment of established PDL1 + TNBC xenograft model with F i-CAR-T cells resulted in significant abrogation in tumor growth and improved survival of mice (71 days), compared to non-armored CAR cells targeting ROR1 (F CAR-T) alone (49 days) or in combination with systemically administered anti-PD-1 antibody (57 days). Crucially, a threefold increase in tumor-infiltrating T cells was observed with F i-CAR-T cells and was associated with increased expression of genes related to cytotoxicity, migration and proliferation.

Conclusions

Our next-generation of ROR1-targeting inducible armored CAR platform enables the release of an immune stimulating payload only in the presence of target tumor cells, enhancing the therapeutic activity of the CAR-T cells. This technology provided a significant survival advantage in TNBC xenograft models. This coupled with its potential safety attributes merits further clinical evaluation of this approach in TNBC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13058-022-01531-1.

The Novel Therapeutic Landscape for Relapsed/Refractory Diffuse Large B Cell Lymphoma

Diffuse large B cell lymphoma (DLBCL) is an aggressive malignancy that has been traditionally treated with anthracycline-based chemotherapy, but approximately one-third of patients relapse after first-line therapy or have primary refractoriness. In this focused review, we discuss the 7 novel Food & Drug Administration (FDA)-approved medications for relapsed/refractory (R/R) DLBCL. We describe 5 CD19-targeted therapies, 3 of which are chimeric antigen receptor (CAR)-T cell therapies. We also highlight novel non-cell-based targeted therapies and discuss optimal sequencing considerations based on the goal of treatment, with an emphasis on CAR-T cell therapy as curative intent. We consider the limited tolerability of certain novel agents, prospects for elderly patients, and financial aspects of these approaches. We discuss advantages and limitations of these targeted therapies based on seminal clinical trials. Finally, we summarize ongoing trials involving promising agents making their way into the pharmacologic pipeline. These therapies include allogeneic CAR-T treatments and multi-antigen targeting therapies such as the CD19/CD22 CAR-T and the CD3/CD20 bispecific antibodies mosunetuzumab and odronextamab. We summarize our approach based on the best available evidence as we enter 2022.

Modulating tumor physical microenvironment for fueling CAR-T cell therapy

Chimeric antigen receptor (CAR) T cell therapy has achieved unprecedented clinical success against hematologic malignancies. However, the transition of CAR-T cell therapies for solid tumors is limited by heterogenous antigen expression, immunosuppressive microenvironment (TME), immune adaptation of tumor cells and impeded CAR-T-cell infiltration/transportation. Recent studies increasingly reveal that tumor physical microenvironment could affect various aspects of tumor biology and impose profound impacts on the antitumor efficacy of CAR-T therapy. In this review, we discuss the critical roles of four physical cues in solid tumors for regulating the immune responses of CAR-T cells, which include solid stress, interstitial fluid pressure, stiffness and microarchitecture. We highlight new strategies exploiting these features to enhance the therapeutic potency of CAR-T cells in solid tumors by correlating with the state-of-the-art technologies in this field. A perspective on the future directions for developing new CAR-T therapies for solid tumor treatment is also provided.

A clinically applicable prediction model to improve T-cell collection in CAR-T cell therapy

As chimeric antigen receptor T (CAR-T) cell therapy targeting CD19 has shown favorable outcomes in patients with relapsed or refractory (r/r) mature B-cell lymphomas and B-cell acute lymphoblastic leukemia (B-ALL), the number of patients who are waiting to receive these treatments is increasing. Optimized protocols for T-cell collection by lymphapheresis for chimeric antigen receptor (CAR) -T cell therapy must be urgently established to provide CAR-T cell therapy for patients with refractory and progressive disease, and/or a low number of lymphocytes due to prior chemotherapies. Predicted collection efficiency of CD3⁺ cells in apheresis can guide protocols for apheresis, but a clinically applicable model to produce reliable estimates has not been established yet. Therefore, we prospectively analyzed lymphapheresis procedures for tisagenlecleucel therapy at two centers. A total of 108 apheresis procedures included 20 procedures for patients with B-cell acute lymphoblastic leukemia, and 88 for patients with diffuse large B-cell lymphoma, with a median age at apheresis of 58 years (1-71). After lymphapheresis with a median processing blood volume of 10 L (3-16), a median of 3.2 × 10⁹ (0.1-15.0) CD3⁺ cells were harvested. Collection efficiency 2 (CE2) for CD3⁺ cells was highly variable (median, 59.3%; range 11.0-199.8). Multivariate analyses revealed that lower Hgb levels, higher circulating CD3⁺ cell counts, and higher platelet counts before apheresis significantly decreased apheresis CE2. Based on multivariate analyses, we developed a novel formula that estimates CE2 from pre-collection parameters with high accuracy (r = 0.56, p < 0.01), which also suggests the necessary processing blood volume. Our strategy in lymphapheresis should be helpful to reduce collection failure, as well as to achieve efficient utilization of medical resources in clinical practice, thereby delivering CAR-T cell therapy to more patients in a timely manner.

The Effects of Chimeric Antigen Receptor (CAR) Hinge Domain Post-Translational Modifications on CAR-T Cell Activity

To improve the efficacy and safety of chimeric antigen receptor (CAR)-expressing T cell therapeutics through enhanced CAR design, we analysed CAR structural factors that affect CAR-T cell function. We studied the effects of disulphide bonding at cysteine residues and glycosylation in the HD on CAR-T function. We used first-generation CAR[V/28/28/3z] and CAR[V/8a/8a/3z], consisting of a mouse vascular endothelial growth factor receptor 2 (VEGFR2)-specific single-chain variable fragment tandemly linked to CD28- or CD8α-derived HD, transmembrane domain (TMD) and a CD3ζ-derived signal transduction domain (STD). We constructed structural variants by substituting cysteine with alanine and asparagine (putative N-linked glycosylation sites) with aspartate. CAR[V/28/28/3z] and CAR[V/8a/8a/3z] formed homodimers, the former through a single HD cysteine residue and the latter through the more TMD-proximal of the two cysteine residues. The absence of disulphide bonds did not affect membrane CAR expression but reduced antigen-specific cytokine production and cytotoxic activity. CAR[V/28/28/3z] and CAR[V/8a/8a/3z] harboured one N-linked glycosylation site, and CAR[V/8a/8a/3z] underwent considerable O-linked glycosylation at an unknown site. Thus, N-linked glycosylation of CAR[V/28/28/3z] promotes stable membrane CAR expression, while having no effect on the expression or CAR-T cell activity of CAR[V/8a/8a/3z]. Our findings demonstrate that post-translational modifications of the CAR HD influence CAR-T cell activity, establishing a basis for future CAR design.

Visualizing CAR-T cell Immunotherapy Using 3 Tesla Fluorine-19 MRI

PURPOSE

Chimeric antigen receptor (CAR) T cell cancer immunotherapies have shown remarkable results in patients with hematological malignancies and represent the first approved genetically modified cellular therapies. However, not all blood cancer patients respond favorably, serious side effects have been reported, and the treatment of solid tumors has been a challenge. An imaging tool for visualizing the variety of CAR-T cell products in use and being explored could provide important patient-specific data on CAR-T cell location to inform on potential success or failure of treatment as well as off-target toxicities. Fluorine-19 (19F) magnetic resonance imaging (MRI) allows for the noninvasive detection of 19F perfluorocarbon (PFC) labeled cells. Our objective was to visualize PFC-labeled (PFC +) CAR-T cells in a mouse model of leukemia using clinical field strength (3 Tesla) 19F MRI and compare the cytotoxicity of PFC + versus unlabeled CAR-T cells.

PROCEDURES

NSG mice (n = 17) received subcutaneous injections of CD19 + human B cell leukemia cells (NALM6) expressing firefly luciferase in their left hind flank (1 × 106). Twenty-one days later, each mouse received an intratumoral injection of 10 × 106 PFC + CD19-targeted CAR-T cells (n = 6), unlabeled CD19-targeted CAR-T cells (n = 3), PFC + untransduced T cells (n = 5), or an equivalent volume of saline (n = 3). 19F MRI was performed on mice treated with PFC + CAR-T cells days 1, 3, and 7 post-treatment. Bioluminescence imaging (BLI) was performed on all mice days - 1, 5, 10, and 14 post-treatment to monitor tumor response.

RESULTS

PFC + CAR-T cells were successfully detected in tumors using 19F MRI on days 1, 3, and 7 post-injection. In vivo BLI data revealed that mice treated with PFC + or PFC - CAR-T cells had significantly lower tumor burden by day 14 compared to untreated mice and mice treated with PFC + untransduced T cells (p < 0.05). Importantly, mice treated with PFC + CAR-T cells showed equivalent cytotoxicity compared to mice receiving PFC - CAR-T cells.

CONCLUSIONS

Our studies demonstrate that clinical field strength 19F MRI can be used to visualize PFC + CAR-T cells for up to 7 days post-intratumoral injection. Importantly, PFC labeling did not significantly affect in vivo CAR-T cell cytotoxicity. These imaging tools may have broad applications for tracking emerging CAR-T cell therapies in preclinical models and may eventually be useful for the detection of CAR-T cells in patients where localized injection of CAR-T cells is being pursued.

Harnessing the chemokine system to home CAR-T cells into solid tumors

CAR-T cell therapy has been heralded as a breakthrough in the field of immunotherapy, but to date, this success has been limited to hematological malignancies. By harnessing the chemokine system and taking into consideration the chemokine expression profile in the tumor microenvironment, CAR-T cells may be homed into tumors to facilitate direct tumor cell cytolysis and overcome a major hurdle in generating effective CAR-T cell responses to solid cancers.

Targeting BCMA to Treat Multiple Myeloma: Updates From the 2021 ASH Annual Meeting

With the gradual improvement of treatment regimens, the survival time of multiple myeloma (MM) patients has been significantly prolonged. Even so, MM is still a nightmare with an inferior prognosis. B-cell maturation antigen (BCMA) is highly expressed on the surface of malignant myeloma cells. For the past few years, significant progress has been made in various BCMA-targeted immunotherapies for treating patients with RRMM, including anti-BCMA mAbs, antibody-drug conjugates, bispecific T-cell engagers, and BCMA-targeted adoptive cell therapy like chimeric antigen receptor (CAR)-T cell. The 63rd annual meeting of the American Society of Hematology updated some information about the application of BCMA in MM. This review summarizes part of the related points presented at this conference.

PiggyBac Transposon-Mediated CD19 Chimeric Antigen Receptor-T Cells Derived From CD45RA-Positive Peripheral Blood Mononuclear Cells Possess Potent and Sustained Antileukemic Function

The quality of chimeric antigen receptor (CAR)-T cell products, namely, memory and exhaustion markers, affects the long-term functionality of CAR-T cells. We previously reported that piggyBac (PB) transposon-mediated CD19 CAR-T cells exhibit a memory-rich phenotype that is characterized by the high proportion of CD45RA⁺/C-C chemokine receptor type 7 (CCR7)⁺ T-cell fraction. To further investigate the favorable phenotype of PB-CD19 CAR-T cells, we generated PB-CD19 CAR-T cells from CD45RA⁺ and CD45RA⁻ peripheral blood mononuclear cells (PBMCs) (RA⁺ CAR and RA⁻ CAR, respectively), and compared their phenotypes and antitumor activity. RA⁺ CAR-T cells showed better transient gene transfer efficiency 24 h after transduction and superior expansion capacity after 14 days of culture than those shown by RA⁻ CAR-T cells. RA⁺ CAR-T cells exhibited dominant CD8 expression, decreased expression of the exhaustion marker programmed cell death protein-1 (PD-1) and T-cell senescence marker CD57, and enriched naïve/stem cell memory fraction, which are associated with the longevity of CAR-T cells. Transcriptome analysis showed that canonical exhaustion markers were downregulated in RA⁺ CAR-T, even after antigen stimulation. Although antigen stimulation could increase CAR expression, leading to tonic CAR signaling and exhaustion, the expression of CAR molecules on cell surface after antigen stimulation in RA⁺ CAR-T cells was controlled at a relatively lower level than that in RA⁻ CAR-T cells. In the in vivo stress test, RA⁺ CAR-T cells achieved prolonged tumor control with expansion of CAR-T cells compared with RA⁻ CAR-T cells. CAR-T cells were not detected in the control or RA⁻ CAR-T cells but RA⁺ CAR-T cells were expanded even after 50 days of treatment, as confirmed by sequential bone marrow aspiration. Our results suggest that PB-mediated RA⁺ CAR-T cells exhibit a memory-rich phenotype and superior antitumor function, thus CD45RA⁺ PBMCs might be considered an efficient starting material for PB-CAR-T cell manufacturing. This novel approach will be beneficial for effective treatment of B cell malignancies.

Prospect of Prostate Cancer Treatment: Armed CAR-T or Combination Therapy

The incidence rate of prostate cancer is higher in male cancers. With a hidden initiation of disease and long duration, prostate cancer seriously affects men's physical and mental health. Prostate cancer is initially androgen-dependent, and endocrine therapy can achieve good results. However, after 18-24 months of endocrine therapy, most patients eventually develop castration-resistant prostate cancer (CRPC), which becomes metastatic castration resistant prostate cancer (mCRPC) that is difficult to treat. Chimeric Antigen Receptor T cell (CAR-T) therapy is an emerging immune cell therapy that brings hope to cancer patients. CAR-T has shown considerable advantages in the treatment of hematologic tumors. However, there are still obstacles to CAR-T treatment of solid tumors because the physical barrier and the tumor microenvironment inhibit the function of CAR-T cells. In this article, we review the progress of CAR-T therapy in the treatment of prostate cancer and discuss the prospects and challenges of armed CAR-T and combined treatment strategies. At present, there are still many obstacles in the treatment of prostate cancer with CAR-T, but when these obstacles are solved, CAR-T cells can become a favorable weapon for the treatment of prostate cancer.

Better by design: What to expect from novel CAR-engineered cell therapies?

Chimeric antigen receptor (CAR) technology, and CAR-T cells in particular, have emerged as a new and powerful tool in cancer immunotherapy since demonstrating efficacy against several hematological malignancies. However, despite encouraging clinical results of CAR-T cell therapy products, a significant proportion of patients do not achieve satisfactory responses, or relapse. In addition, CAR-T cell applications to solid tumors is still limited due to the tumor microenvironment and lack of specifically targetable tumor antigens. All current products on the market, as well as most investigational CAR-T cell therapies, are autologous, using the patient's own peripheral blood mononuclear cells as starting material to manufacture a patient-specific batch. Alternative cell sources are, therefore, under investigation (e.g. allogeneic cells from an at least partially human leukocyte antigen (HLA)-matched healthy donor, universal "third-party" cells from a non-HLA-matched donor, cord blood-derived cells, immortalized cell lines or cells differentiated from induced pluripotent stem cells). However, genetic modifications of CAR-engineered cells, bioprocesses used to expand cells, and improved supply chains are still complex and costly. To overcome drawbacks associated with CAR-T technologies, novel CAR designs have been used to genetically engineer cells derived from alpha beta (αβ) T cells, other immune cells such as natural killer (NK) cells, gamma delta (γδ) T cells, macrophages or dendritic cells. This review endeavours to trigger ideas on the next generation of CAR-engineered cell therapies beyond CAR-T cells and, thus, will enable effective, safe and affordable therapies for clinical management of cancer. To achieve this, we present a multidisciplinary overview, addressing a wide range of critical aspects: CAR design, development and manufacturing technologies, pharmacological concepts and clinical applications of CAR-engineered cell therapies. Each of these fields employs a large number of ground-breaking scientific advances, where coordinated and complex process and product development occur at their interfaces.

Real-world eligibility for second-line CAR-T cell therapy in large B-cell lymphoma: a population-based analysis

The ZUMA-7 trial demonstrated the superiority of second-line CAR-T cell therapy over standard of care chemotherapy +/- autotransplant for relapsed/refractory (r/r) large B-cell lymphoma (LBCL). We conducted a retrospective, population-based analysis to determine eligibility for second-line CAR-T cell therapy in the real-world setting. Among 125 patients with r/r LBCL between 2015-2019, 82% progressed within 12 months of first-line chemoimmunotherapy (CIT), 40% were treated with intention-to-transplant, 22% underwent autotransplant, and 7% achieved a durable remission after autotransplant. With median follow-up time 2.8 years, median OS was 5.1 months and 3-year OS was 15% (95% CI 7-20%) for all patients and 10% (95% CI 5-17%) for those progressing within 12 months of CIT. Although only 14% of patients fulfilled all ZUMA-7 study inclusion criteria, as many as 65% of patients progressing within 12 months of CIT had adequate performance status to be considered potentially eligible for second-line CAR-T cell therapy. Whereas the current standard of care results in poor outcomes for most patients with r/r LBCL, the use of CAR-T cell therapy in second line could substantially increase the proportion of patients able to receive curative-intent treatment at first progression of LBCL.

Resistance and recurrence of malignancies after CAR-T cell therapy

The emergence of chimeric antigen receptor T (CAR-T) cell therapy has ushered a new era in cancer therapy, especially the treatment of hematological malignancies. However, resistance and recurrence still occur in some patients after CAR-T cell treatment. CAR-T cell inefficiency and tumor escape have emerged as the main challenges for the long-term disease control of B cell malignancies by this promising immunotherapy. In solid tumor treatment, CAR-T cells must also overcome many hurdles from the tumor or immune-suppressed tumor environment, which have become obstacles to the advancement of CAR-T therapy. Therefore, an understanding of the mechanisms underlying post-CAR treatment failure in patients is necessary. In this review, we characterize some mechanisms of resistance and recurrence after CAR-T cell therapy and correspondingly suggest reasonable treatment strategies.

Establishing functional lentiviral vector production in a stirred bioreactor for CAR-T cell therapy

As gene delivery tools, lentiviral vectors (LV) have broad applications in chimeric antigen receptor therapy (CAR-T). Large-scale production of functional LV is limited by the adherent, serum-dependent nature of HEK293T cells used in the manufacturing. HEK293T adherent cells were adapted to suspension cells in a serum-free medium to establish large-scale processes for functional LV production in a stirred bioreactor without micro-carriers. The results showed that 293 T suspension was successfully cultivated in F media (293 CD05 medium and SMM293-TII with 1:1 volume ratio), and the cells retained the capacity for LV production. After cultivation in a 5.5 L bioreactor for 4 days, the cells produced 1.5 ± 0.3 × 107 TU/mL raw LV, and the lentiviral transduction efficiency was 48.6 ± 2.8% in T Cells. The yield of LV equaled to the previous shake flask. The critical process steps were completed to enable a large-scale LV production process. Besides, a cryopreservation solution was developed to reduce protein involvement, avoid cell grafting and reduce process cost. The process is cost-effective and easy to scale up production, which is expected to be highly competitive.

Outcome of patients with mantle cell lymphoma after autologous stem cell transplantation in the pre-CAR T-cell era

Mantle cell lymphoma (MCL) patients can be treated with intensive induction therapy, followed by high dose chemotherapy (HDCT) with autologous stem cell transplantation (ASCT) for consolidation and subsequent anti-CD20 maintenance. For patients relapsing after bruton tyrosine kinase (BTK) inhibitors, CAR T-cell therapy became available in late 2020 fueling the interest in outcomes of relapsing MCL patients. We retrospectively analyzed the outcome of MCL patients receiving HDCT/ASCT at our center between 2000 and 2021, thus, before availability of CAR-T cells. We identified 97 MCL patients undergoing HDCT/ASCT in this period with a median follow-up of 52 months. 43 (44%) patients ultimately relapsed, and 29 (30%) have died. The median progression-free survival (PFS) for the entire cohort was 48 months and overall survival (OS) was 202 months. Relapsing patients had a median PFS of only 28 months and median OS of 105 months. The OS of relapsing patients receiving BTK inhibitors was 148 versus 78 months in patients who never received BTK inhibitors (p = 0.1175). Even after HDCT/ASCT, a substantial proportion of MCL patients will relapse and ultimately die of the disease, emphasizing the need for new therapeutic options including CAR T-cell treatment for this lymphoma subtype.

Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular Consensus on genetically modified cells. V: Manufacture and quality control

Chimeric antigen receptor T cells (CAR-T), especially against CD19 marker, present in lymphomas and acute B leukemia, enabled a revolution in the treatment of hematologic neoplastic diseases. The manufacture of CAR-T cells requires the adoption of GMP-compatible methods and it demands the collection of mononuclear cells from the patient (or from the donor), generally through the apheresis procedure, T cell selection, activation, transduction and expansion ex vivo, and finally storage, usually cryopreserved, until the moment of their use. An important aspect is the quality control testing of the final product, for example, the characterization of its identity and purity, tests to detect any contamination by microorganisms (bacteria, fungi, and mycoplasma) and its potency. The product thawing and intravenous infusion do not differ much from what is established for the hematopoietic progenitor cell product. After infusion, it is important to check for the presence and concentration of CAR-T cells in the patient's peripheral blood, as well as to monitor their clinical impact, for instance, the occurrence of short-term, such as cytokine release syndrome and neurological complications, and long-term complications, which require patient follow-up for many years.

Cancer Vaccines and Immunotherapy for Tumor Prevention and Treatment

In this editorial, we highlight articles published in this Special Issue of Vaccines on “Cancer Vaccines and Immunotherapy for Tumor Prevention and Treatment”, recent developments in the field of cancer vaccines, and the potential for immunotherapeutic combinations in cancer care. This issue covers important developments and progress being made in the cancer vaccine field and possible future directions for exploring new technologies to produce optimal immune responses against cancer and expand the arena of prophylactic and therapeutic cancer vaccines for the treatment of this deadly disease.

CAR-T cell therapy in India requires a paradigm shift in training, education and health care processes

Chimeric antigen receptor (CAR)-T cell therapy has revolutionized the treatment of some kinds of cancers. Hundreds of companies and academic institutions are collaborating to develop gene-modified cell therapies using novel targets, different cell types, and manufacturing processes of autologous and allogenic cell therapies. The individualized, custom-made autologous CAR-T cell production platform remains a significant limiting factor for its large-scale clinical application. In this respect, the advances in standardization and automation of the process can have considerable impact on cost reduction. Development of off-the-shelf, ready-to-use universal killer cells can enable scaling up. Despite the wide use of this cell therapy in the United States, Europe and China, its development is limited in developing countries in Southeast Asia, Africa and Latin America. In this review, we focus on good manufacturing practices-compliant manufacturing requirements, operational logistics, and regulatory processes that need to be considered for high-quality gene-modified cell therapies from an Indian perspective. We also list the potential strategies to overcome challenges associated with translation to affordability and scalability.

Phase I study of CBM.CD19 chimeric antigen receptor T cell in the treatment of refractory diffuse large B-cell lymphoma in Chinese patients

Anti-CD19 chimeric antigen receptor (CAR) T cell therapy has shown impressive efficacy in treating B-cell malignancies. A single-center phase I dose-escalation study was conducted to evaluate the safety and efficacy of T cells transduced with CBM.CD19 CAR, a second-generation anti-CD19 CAR bearing 4-1BB costimulatory molecule, for the treatment of patients with refractory diffuse large B-cell lymphoma (DLBCL). Ten heavily treated patients with refractory DLBCL were given CBM.CD19 CAR-T cell (C-CAR011) treatment. The overall response rate was 20% and 50% at 4 and 12 weeks after the infusion of C-CAR011, respectively, and the disease control rate was 60% at 12 weeks after infusion. Treatment-emergent adverse events occurred in all patients. The incidence of cytokine release syndrome in all grades and grade ⩾ 3 was 90% and 0, respectively, which is consistent with the safety profile of axicabtagene ciloleucel and tisagenlecleucel. Neurotoxicity or other dose-limiting toxicities was not observed in any dose cohort of C-CAR011 therapy. Antitumor efficacy was apparent across dose cohorts. Therefore, C-CAR011 is a safe and effective therapeutic option for Chinese patients with refractory DLBCL, and further large-scale clinical trials are warranted.

How to Sequence Therapies in Diffuse Large B-Cell Lymphoma Post-CAR-T Cell Failure

OPINION STATEMENT

Post CAR-T failures represent a new unmet need in R/R LBCL. The prognosis is usually very poor and standard treatment options that can guide clinicians are, unfortunately, not available. While polatuzumab, tafasitamab, selinexor, and loncastuximab tesirine are available as SOC since they are FDA approved, data is lacking in the post CAR-T setting. However, they could be used in the absence of other treatment options (clinical trials). A selected group of patients may be treated with checkpoint inhibitors, likely low tumor burden or low proliferative lymphomas or those with PD-L1 expression. For localized relapses, radiation therapy could be considered. A main consideration should be given to clinical trials. So far, it appears that bi-specific antibodies have the best encouraging data (high response rates) with manageable toxicities and logistics; thus, we recommend clinicians to enroll patients in clinical trials utilizing these agents. Other cell therapies (such as dual CAR-T or allogeneic products) should also be considered; however, challenges with logistics and further immunosuppression (especially if patients had prolonged cytopenias from prior CAR-T therapy) may affect its applicability right after CAR-T relapse. It is unclear whether these options will lead to long-term remissions; thus, consolidation with stem cell transplantation (either auto or allogeneic SCT) could be considered in eligible patients.

An overview of multiplexed analyses of CAR T-cell therapies: insights and potential

INTRODUCTION

Cancer immunotherapy is a rapidly growing field with exponential advancement in engineered immune cell-based therapies. For instance, an engineered chimeric antigen receptor (CAR) can be introduced in T-cells or other immune cells and adoptively transferred to target and kill cancer cells in hematologic malignancies or solid tumors. The first CAR-T-cell (CAR-T) therapy has been developed against CD19, a B-cell marker expressed on lymphoma and lymphoblastic leukemia. To allow for personalized treatment, proteomics approaches could provide insights into biomarkers for CAR-T therapy efficacy and toxicity.

AREAS COVERED

We researched the most recent technology methods of biomarker evaluation used in the laboratory and clinical setting. Publications of CAR-T biomarkers were then systematically reviewed to provide a narrative of the most validated biomarkers of CAR-T efficacy and toxicity. Examples of biomarkers include CAR-T functionality and phenotype as well as interleukin-6 and other cytokines.

EXPERT COMMENTARY

Biomarkers of CAR-T efficacy and toxicity have been identified, but still need to be validated and standardized across institutions. Moreover, few are used in the clinical setting due to limitations in real-time technology. Expansion of biomarker research could provide better understanding of patient response and risk of life-threatening side effects with potential for improved precision medicine.