Incidence of Secondary Malignancy after Treatment with Anti-CD19 and Anti-BCMA Chimeric Antigen Receptor T-Cell Therapies

Chimeric antigen receptor T-cell (CAR-T) cell therapy represents a significant advancement in cancer treatment, offering remarkable responses in certain hematologic malignancies. However, the risk of secondary primary malignancies (SPMs) associated with CAR-T therapy is a growing concern. Recent studies suggest that antibiotics, which are frequently used in CAR-T patients, may influence this risk, yet their effects remain poorly understood. This study aims to systematically evaluate the association between antibiotics and the incidence and timing of SPMs in patients receiving CAR-T cell therapy, using data from the FDA's Adverse Event Reporting System (FAERS) database. We analyzed reports from FAERS spanning from Q2 2017 to Q1 2024, focusing on SPMs associated with various CAR-T therapies. A comprehensive signal analysis was conducted to explore the associations between antibiotic usage and specific SPMs for different CAR-T products. In addition, we employed cumulative hazard curves to evaluate the time to onset of SPMs in patients receiving antibiotics versus those who did not. We have provided a comprehensive summary of all signals for CAR-T-associated SPMs. In addition, our analysis identified significant variations in the association between antibiotics and SPM incidence depending on the CAR-T therapy administered. Antibiotics were associated with a decreased risk of SPMs in patients treated with anti-CD19 CAR-T therapies, particularly brexucabtagene autoleucel. Conversely, a higher risk of SPMs was observed in association with antibiotics for anti-BCMA therapies, with idecabtagene vicleucel showing a notably elevated risk. Notably, antibiotics were associated with an earlier onset of SPMs across CAR-T therapies, suggesting a possible relationship between antibiotics and the timing of these malignancies. Finally, we explored the underlying biological pathways that may be associated with these observations. Antibiotics were associated with both the risk and timing of SPMs in patients undergoing CAR-T cell therapy. This study highlights the need for further research to better understand the complex interactions between antibiotics and CAR-T therapies, as well as the potential implications for clinical management and patient care.

Systematic Review of Secondary Primary Malignancies (SPMs) in Patients Treated with Chimeric Antigen Receptor T-Cell (CAR-T) Therapies

Although anti-CD19 chimeric antigen receptor (CAR) T-cell therapy shows good efficacy in patients with relapsed/refractory B-cell acute lymphoblastic leukemia (r/r B-ALL), it fails to improve long-term leukemia-free survival (LFS). Allogeneic hematopoietic stem cell transplantation (allo-HSCT) after CAR T-cell therapy has emerged as a promising strategy to prolong LFS. Nevertheless, which patients are likely to benefit from consolidative allo-HSCT, as well as the optimal therapeutic window, remain to be explored. Recent clinical data indicate that patients with complex karyotypes, adverse genes, and high pre-infusion minimal residual disease (MRD) by flow cytometry in the bone marrow, were at high risk of relapse after CAR T-cell therapy. High pre-lymphodepletion lactate dehydrogenase, low pre-lymphodepletion platelet count, absence of fludarabine in lymphodepletion, persistent leukemic sequence by high throughput sequencing in bone marrow after CAR T-cell infusion, and early loss of CAR T cells have also been linked to relapse after CAR T-cell therapy. In patients having these risk factors, consolidative allo-HSCT after CAR T-cell therapy may prolong LFS. Allo-HSCT provides optimal clinical benefit in patients with MRD-negative complete remission, typically within three months after CAR T-cell therapy. Herein, we summarize the clinical data on consolidative allo-HSCT after anti-CD19 CAR T-cell therapy, as well as the potential factors associated with allo-HSCT benefit. We also discuss the optimal therapeutic window and regimen of consolidative allo-HSCT. Finally, and most importantly, we provide recommendations for the assessment and management of r/r B-ALL patients undergoing anti-CD19 CAR T-cell therapy.

Pediatric cancer poses a major health challenge globally, especially in low-middle-income countries like Indonesia. The survival rate of pediatric cancer in many high-income countries (HICs) reaches 90%, while it only ranges from 5 to 60% in LMICs. Over 80% of children with cancer live in low-middle-income countries, indicating the urgency to improve the survival rate of pediatric cancer in LMICs [1]. In Indonesia, the prevalence of pediatric cancer was 43.5% in 2020, making it the highest among Southeast Asian countries [2]. According to Dharmais Cancer Hospital (2024), the national cancer referral center for all of Indonesia, the 5-year survival rate of high-risk pediatric acute lymphoblastic leukemia is only 48.8% (unpublished data).One key factor contributing to the low survival rate of pediatric cancer in Indonesia is the lack of effective therapy options, especially for high-risk and relapsed or refractory patients. Several therapeutic approaches, such as immunotherapy, have been widely used in HICs but are still not very popular in Indonesia. CAR (Chimeric Antigen Receptor) T-cell therapy is one of the most promising immunotherapeutic approaches to treat pediatric cancer. Implementing CAR T Cell therapy in Indonesia offers promising prospects for improving the survival rates of pediatric cancer patients.CAR T cell therapy utilizes the body's immune system to specifically target and eliminate cancer cells. This innovative therapy entails extracting a patient's T cells, genetically modifying them to express chimeric antigen receptors specific to tumor-associated antigens, and then reinfusing them into the patient. Once infused, these engineered T cells recognize and eliminate cancer cells bearing the targeted antigen, thereby offering a highly targeted and potentially curative treatment option [3]. This innovative therapy has demonstrated remarkable success in treating certain hematologic malignancies, including pediatric leukemia. The most extensively studied case in childhood patients involves CAR T cells that target CD19, a B cell surface receptor [4].CAR T cell therapy holds great promise for improving survival rates among pediatric cancer patients in Indonesia. Children with refractory or relapsed leukemia, such as B-cell acute lymphoblastic leukemia (B-ALL), who have exhausted standard treatment options, can benefit from CAR T cell therapy. Most relapsed or refractory pediatric cancer patients in Indonesia do not have effective therapy options to treat the disease. CAR T cell therapy emerges as a novel therapy that can significantly improve the survival of this subset of patients. Numerous studies have documented high remission rates (ranging from 70% to 90%) in adults and children diagnosed with refractory B-ALL [4]. A study by Maude et al. [5] reported high remission rates and durable responses in young adults and children with refractory or relapsed B-ALL treated with CAR T cells. Similarly, Park et al. [6] demonstrated long-term remissions and improved survival in pediatric leukemia patients receiving CAR T cell therapy. Several groups also have observed the persistence of CAR T cells and sustained remission lasting over six months in the majority of patients examined [4]. Efforts have been made to implement CAR T cells in Indonesia. Dharmais Cancer Hospital, as a National Cancer Center in Indonesia, has initiated this effort by collaborating with iCarTAB Biomed Inc., a China-based CAR T cell manufacturer with one of its manufacturing sites located in Malaysia. However, this approach involves sending patients' blood samples that have been processed through leukapheresis to Malaysia for CAR T cell manufacturing, followed by the shipment of the manufactured cells back to Indonesia for administration to patients. This process is impractical and incurs intangible costs such as transportation and cryopreservation, ultimately making it more expensive for patients. Regulatory issues related to the shipment of cells across borders in the region and early preparation of patients for CAR T cell therapy soon after relapse before they succumb to treatment-related mortality or relapse-related complications are also challenges that need to be addressed [7]. Reflecting on the abovementioned issue, CAR T cell therapy adoption in Indonesia faces significant challenges. Limited healthcare infrastructure, including specialized facilities for cell therapy manufacturing and administration, poses logistical hurdles. Moreover, cost remains a major barrier, as CAR T cell therapy is often expensive and inaccessible to many patients in Indonesia. Furthermore, the lack of local expertise in cellular immunotherapy may impede the successful implementation of CAR T cell therapy programs.Efforts to address these challenges and maximize the potential of CAR T cell therapy in Indonesia are essential. This requires a multi-faceted approach involving investment in healthcare infrastructure, including establishing specialized centers equipped for CAR T cell therapy manufacturing and administration. Two alternative models have been proposed for manufacturing CAR-T cell therapy: centralized and de-centralized models [8]. In the centralized manufacturing model, point of manufacturing and point of care are located in different geographical areas, while decentralized manufacturing focuses on establishing point of care and manufacturing in close proximity. A decentralized manufacturing model might be the best approach to be implemented in LMICs like Indonesia. Building hospital-based cellular therapy manufacturing reduces the need for transportation and cryopreservation. The decentralized system's geographic proximity improves communication between manufacturing and treatment teams, facilitating the creation of customized products based on a patient's phenotype. This setup also reduces administration time and the risk of delays and mix-ups compared to centralized manufacturing, making hospital-based cellular therapy manufacturing a potentially more cost-effective option [8].In addition, initiatives to reduce the cost of therapy through partnerships with pharmaceutical companies, government subsidies, or philanthropic endeavors can improve affordability and access. Furthermore, capacity-building initiatives aimed at training local healthcare professionals in cellular immunotherapy techniques are essential for ensuring the successful implementation and sustainability of CAR T cell therapy programs in Indonesia. Collaboration between local institutions, international organizations, and industry stakeholders can facilitate knowledge transfer and technology transfer, fostering indigenous expertise in this cutting-edge treatment modality.CAR T cell therapy represents a transformative approach to improving survival rates among pediatric cancer patients in Indonesia. By harnessing the power of immunotherapy, specifically tailored to target cancer cells, CAR T cell therapy offers hope for children with refractory or relapsed leukemia who have limited treatment options. Through continued research, collaboration, and investment in healthcare infrastructure, CAR T cell therapy potentially could greatly improve the prognosis and quality of life for pediatric cancer patients in Indonesia.

With impressive clinical advancements in immune effector cell therapies targeting CD19, chimeric antigen receptor (CAR) T-cell therapy has emerged as a new paradigm for treating relapsed/refractory B-cell malignancies. Currently, three second-generation CAR T-cell therapies have been approved, of which only tisagenlecleucel (tisa-cel) is approved for treating children and young adults with B-cell acute lymphoblastic leukemia (ALL) with durable remission rates of approximately 60‒90%. Although CAR T-cell therapies are considered to treat refractory B-ALL, they are associated with unique toxicities such as cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). The severity of CAR T-cell therapy toxicities can vary according to several clinical factors. In rare cases, severe CRS can progress to a fulminant hyperinflammatory syndrome known as hemophagocytic lymphohistiocytosis, which has a poor prognosis. The first-line treatments for CRS/ICANS include tocilizumab and corticosteroids. When severe CAR T-cell toxicity is resistant to first-line treatment, an additional approach is required to manage the persistent inflammation. In addition to CRS/ICANS, CAR T-cell therapy can cause early and delayed hematological toxicity, which can predispose patients to severe infections. The use of growth factors and anti-infective prophylaxis should follow institutional guidelines according to patient-specific risk factors. This review provides a thorough summary of updated practical recommendations for managing acute and delayed adverse effects following anti-CD19 CAR T-cell therapy in adults and children.

In “Long-term Neurologic Safety in Patients With B-Cell Lymphoma Treated With Anti-CD19 Chimeric Antigen Receptor (CAR) T-Cell Therapy,” Ursu et al. report that although 11 of 19 patients with refractory lymphoma developed acute neurotoxicity after treatment with CAR T-cell therapy and 0 of 19 had a change in cognitive performance or MRI 2 years after treatment. Karschnia et al. note that these findings must be interpreted cautiously given the small sample size and lack of additional treatment after CAR T-cell therapy, particularly given that other data demonstrate long-term visuospatial, cognitive, and neuropsychiatric symptoms after treatment with CAR T-cell therapy. In contrast, Tan et al. praise the study methodology and cite two other studies with similar findings. This discussion demonstrates the importance for future studies using CAR T-cell therapy to include long-term neuropsychological testing and a larger sample size. In “Long-term Neurologic Safety in Patients With B-Cell Lymphoma Treated With Anti-CD19 Chimeric Antigen Receptor (CAR) T-Cell Therapy,” Ursu et al. report that although 11 of 19 patients with refractory lymphoma developed acute neurotoxicity after treatment with CAR T-cell therapy and 0 of 19 had a change in cognitive performance or MRI 2 years after treatment. Karschnia et al. note that these findings must be interpreted cautiously given the small sample size and lack of additional treatment after CAR T-cell therapy, particularly given that other data demonstrate long-term visuospatial, cognitive, and neuropsychiatric symptoms after treatment with CAR T-cell therapy. In contrast, Tan et al. praise the study methodology and cite two other studies with similar findings. This discussion demonstrates the importance for future studies using CAR T-cell therapy to include long-term neuropsychological testing and a larger sample size.

Long-Term Outcomes and Adverse Events of CAR T-19 Cell Therapy in Relapsed or Refractory B-Cell Acute Lymphoblastic Leukemia - a Systematic Review and Meta-Analysis

Radiotherapy Is an Excellent Bridging Strategy in Large B-Cell Lymphoma Patients Selected for CAR T-Cell Therapy

Chimeric antigen receptor (CAR) T-cell therapies have revolutionised the field of haematological malignancies by achieving impressive remission rates in patients with highly refractory haematological malignancies, improving overall survival. To date, six commercial anti-CD19 and anti-BCMA CAR T-cell products have been approved by the Food and Drug Administration (FDA) for the treatment of relapsed/refractory B-cell haematological malignancies and multiple myeloma. The indications for CAR T-cell therapies are gradually expanding, with these therapies being investigated in a variety of diseases, including non-malignant ones. Despite the great success, there are several challenges surrounding CAR T-cell therapies, such as non-durable responses and high-grade toxicities. In addition, a new safety concern was added by the FDA on 28 November 2023 following reports of T-cell malignancies in patients previously treated with either anti-CD19 or anti-BCMA autologous CAR T-cell therapies both in clinical trials and in the real-world setting. Since then, several reports have been published presenting the incidence and analysing the risks of other secondary malignancies after CAR T-cell therapies. In this opinion article, the current landscape of secondary malignancies after CAR T-cell therapies is presented, along with a proposed strategy for future research aiming at potentially diminishing or abrogating the risk of developing secondary malignancies after CAR T-cell therapies.

Significant Long-Term Benefits of CAR T-Cell Therapy Followed By a Second Allo-HSCT for Relapsed/Refractory (R/R) B-Cell Acute Lymphoblastic Leukemia (B-ALL) Patients Who Relapsed after an Initial Transplant

Evaluating Hematologist's Knowledge of CAR T-Cell Therapy in Hematologic Malignancies

Background: Chimeric antigen receptor (CAR) T-cell therapy has significantly advanced the treatment of hematologic malignancies, offering curative potential for patients with relapsed or refractory disease. However, the long-term survivorship of these patients is marked by unique challenges, particularly immune deficits and infectious complications, second primary malignancies (SPMs), and non-relapse mortality (NRM). Understanding and addressing these risks is paramount to improving patient outcomes and quality of life. Summary: This review explores the incidence and risk factors for NRM and long-term complications following CAR T-cell therapy. Infections are the leading cause of NRM, accounting for over 50% of cases, driven by neutropenia, hypogammaglobulinemia, and impaired cellular immunity. SPMs, including secondary myeloid and T-cell malignancies, are increasingly recognized, prompting the FDA to issue a black box warning, although their direct link to CAR T cells remains disputed. While CAR T-cell-specific toxicities like cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome contribute to morbidity, they represent only a minority of NRM cases. The management of these complications is critical as CAR T-cell therapy is being evaluated for broader use, including in earlier treatment lines and for non-malignant conditions like autoimmune diseases. Key Messages: CAR T-cell therapy has revolutionized cancer treatment, but survivorship is complicated by infections, SPMs, and ultimately endangered by NRM. Prophylactic strategies, close monitoring, and toxicity management strategies are key to improving long-term outcomes.

In patients diagnosed with B-acute lymphoblastic leukemia (B-ALL) or B-non-Hodgkin's lymphoma (B-NHL) relapsing after allogeneic stem cell transplantation (allo-HCT), it is a standard practice to perform anti-CD19 chimeric antigen receptor (CAR) T-cell therapy. When collected from the patient after allo-HCT, the produced CAR-T cells are likely to be donor T-cell-derived, creating unknown safety risks due to their potential allo-reactivity. We therefore performed an EBMT registry-based study on the incidence of graft-versus-host disease (GvHD) in this setting. We included 257 allo-HCT patients (n = 172 ≥ 18 years) with B-ALL or B-NHL, treated with anti-CD19 CAR T-cells (tisagenlecleucel n = 184, brexucabtagene autoleucel n = 43 and axicabtagene ciloleucel n = 30), between 2018 and 2022. Three patients developed aGvHD, whereas 6 patients developed cGvHD after CAR T-cell. The 100-day cumulative incidence (CI) of new aGvHD was 1.6% and the 12-month CI of new cGvHD was 2.8%. The 1-year GvHD relapse-free survival and non-relapse mortality were 52.1% and 4.7%, respectively. Last, with a median follow up of 18.8 months, the 1-year overall survival was 76.8%. In summary, the GvHD rate in allo-HCT patients treated with CAR T-cell therapy is relatively low. Our data support the view that GvHD is not a major safety issue in this setting.

Autoimmune Outcomes in Patients with Concurrent Autoimmune Disease Receiving CD19 CAR T-Cell Therapy for Lymphoma

Acute Kidney Injury After the CAR-T Therapy Tisagenlecleucel