CAR T cells induce a complete response in refractory Burkitt Lymphoma

Point-of-care anti-CD19 chimeric antigen receptor T-cell therapy for relapsed/refractory follicular lymphoma

Patients with relapsed/refractory follicular lymphoma (R/R-FL) often require multiple treatment lines. We performed a phase 1b/2 single-center clinical trial of autologous point-of-care anti-CD19 chimeric antigen receptor (CAR) T-cells in R/R-FL patients treated patients with ≥ 2 treatment lines. All 26 patients enrolled received CAR T-cell infusion at a median of 11 days after leukapheresis. Seventy-seven percent of patients had POD24. At enrollment, disease stage was III-IV in 85% of the patients, 77% had high-risk FLIPI score, and 77% had progressive disease. Grade III-IV cytokine release and immune effector cell-associated neurotoxicity syndromes occurred in 12% and 16% of the patients, respectively. Overall response rate at 1-month was 88%. The median follow-up was 15.4 months. One-year overall and progression-free survival were 100% and 63%, respectively. In conclusion, point-of-care CAR T-cell, manufactured within 11 days, induced a high response rate with an acceptable safety profile in patients with high-risk R/R-FL.

Broadening the horizon: potential applications of CAR-T cells beyond current indications

Engineering immune cells to treat hematological malignancies has been a major focus of research since the first resounding successes of CAR-T-cell therapies in B-ALL. Several diseases can now be treated in highly therapy-refractory or relapsed conditions. Currently, a number of CD19- or BCMA-specific CAR-T-cell therapies are approved for acute lymphoblastic leukemia (ALL), diffuse large B-cell lymphoma (DLBCL), mantle cell lymphoma (MCL), multiple myeloma (MM), and follicular lymphoma (FL). The implementation of these therapies has significantly improved patient outcome and survival even in cases with previously very poor prognosis. In this comprehensive review, we present the current state of research, recent innovations, and the applications of CAR-T-cell therapy in a selected group of hematologic malignancies. We focus on B- and T-cell malignancies, including the entities of cutaneous and peripheral T-cell lymphoma (T-ALL, PTCL, CTCL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), chronic lymphocytic leukemia (CLL), classical Hodgkin-Lymphoma (HL), Burkitt-Lymphoma (BL), hairy cell leukemia (HCL), and Waldenström's macroglobulinemia (WM). While these diseases are highly heterogenous, we highlight several similarly used approaches (combination with established therapeutics, target depletion on healthy cells), targets used in multiple diseases (CD30, CD38, TRBC1/2), and unique features that require individualized approaches. Furthermore, we focus on current limitations of CAR-T-cell therapy in individual diseases and entities such as immunocompromising tumor microenvironment (TME), risk of on-target-off-tumor effects, and differences in the occurrence of adverse events. Finally, we present an outlook into novel innovations in CAR-T-cell engineering like the use of artificial intelligence and the future role of CAR-T cells in therapy regimens in everyday clinical practice.

Bone Marrow Aplasia after CAR-T-Cell Therapy for Relapsed/Refractory Burkitt's Lymphoma

Chimeric antigen receptor T-cells (CAR-T) are now a standard approach for treating relapsed/refractory B-cell lymphomas. Immune effector cell-associated hemophagocytic lymphohistiocytosis-like syndrome (IEC-HS) is a newly described entity that can manifest following CAR-T. Bone marrow (BM) aplasia is an uncommon manifestation of IEC-HS reported after CAR-T-cell therapy and is defined as the reduction or absence of hematopoietic progenitor cells resulting in severe pancytopenia. We describe the case of a 44-year-old female with relapsed/refractory Burkitt lymphoma (BL) who received treatment with lisocabtagene maraleucel with her post-CAR-T course complicated by cytokine release syndrome (CRS) and IEC-HS ultimately leading to persistent BM aplasia. She underwent a rescue allogeneic stem cell transplant but ultimately succumbed to progressive disease. IEC-HS is an increasingly recognized complication that occurs after CAR-T treatments that can result in aplasia, a dangerous complication with serious sequelae including infection, transfusion dependence, and high risk for hemorrhage. The underlying mechanism is poorly understood, and further studies are needed to understand how to treat it better.

Case Report: Unedited allogeneic chimeric antigen receptor T cell bridging to conditioning-free hematopoietic stem cell transplantation for a child with refractory Burkitt lymphoma

Purpose

Burkitt lymphoma (BL) is the most common tumor of non-Hodgkin's lymphoma (NHL) in children, accounting for about 40% of cases. Although different combined short-course chemotherapies have achieved a good effect, refractory/relapsed BL has a poor prognosis with cure rates less than 30%. Chimeric antigen receptor T cell (CAR-T) therapy has developed rapidly in recent years and achieved excellent results in acute lymphoblastic leukemia (ALL). However, in some cases, there is a failure to produce autologous CAR-T cells because of T-cell dysfunction. In such cases, allogeneic CAR-T therapy has to be considered.

Methods

A 17-year-old boy with stage II BL did not respond to extensive chemotherapy and sequential autologous CAR-T therapy. Lentiviral vectors containing anti-CD20-BB-ζ (20CAR) and anti-CD22-BB-ζ (22CAR) transgenes were used to modify the T cells from an HLA-identical matched unrelated donor. Flow cytometry was used to assess the cytokine analyses and CAR-T cell persistence in peripheral blood, enumerated by qPCR as copies per ug DNA. Informed consent for autologous/allogeneic CAR-T therapy was obtained from the patient and his legal guardian.

Results

Unedited HLA-matched allogeneic CD20 and CD22 CAR-T cells were infused after lymphodepletion chemotherapy with cyclophosphamide and fludarabine. The patient experienced Grade IV cytokine release syndrome (CRS) and went into complete remission (CR) after anti-inflammatory treatment including tocilizumab. Because of persistent pancytopenia and full donor chimerism, the same donor's conditioning-free peripheral blood stem cells were successfully transplanted 55 days post CAR-T. Neutrophils were engrafted at day +11 and platelets were rebuilt at day +47 without obvious acute graft-versus-host disease (GVHD), but there was mild chronic GVHD in the skin and eyes. Currently, active anti-rejection therapy is still underway.

Conclusion

Unedited HLA-matched allogeneic CAR-T cell therapy could be an innovative, effective, and safe treatment for children with refractory/relapse BL without obvious acute GVHD. Conditioning-free allogeneic hematopoietic stem cell transplantation (HSCT) from the same donor is feasible for a patient with full donor T-cell chimerism after allogeneic CAR-T. It cannot be ignored that close GVHD monitoring is needed post HSCT.

EBV and Lymphomagenesis

The clinical significance of Epstein–Barr virus (EBV) cannot be understated. Not only does it infect approximately 90% of the world’s population, but it is also associated with numerous pathologies. Diseases linked to this virus include hematologic malignancies such as diffuse large B-cell lymphoma, Hodgkin lymphoma, Burkitt lymphoma, primary CNS lymphoma, and NK/T-cell lymphoma, epithelial malignancies such as nasopharyngeal carcinoma and gastric cancer, autoimmune diseases such as multiple sclerosis, Graves’ disease, and lupus. While treatment for these disease states is ever evolving, much work remains to more fully elucidate the relationship between EBV, its associated disease states, and their treatments. This paper begins with an overview of EBV latency and latency-associated proteins. It will then review EBV’s contributions to select hematologic malignancies with a focus on the contribution of latent proteins as well as their associated management.

Case report: Sandwich therapy of CAR-T combined with ASCT: Sequential CAR-T cell therapy with ASCT after remission with CAR-T therapy caused long-term survival in a patient with relapsed/refractory Burkitt’s lymphoma with TP53 mutations

Burkitt’s lymphoma (BL) with TP53 mutation often has poor outcome after standard chemoimmunotherapy. Adoptive chimeric antigen receptor (CAR)-T cell therapy may be a new paradigm for treating refractory/relapsed (r/r) BL, but its therapeutic effects remain inconclusive. Here, we report a patient with r/r BL who failed to achieve complete remission (CR) and progressed rapidly after multiple protocol chemotherapy. The patient achieved CR with CAR19 and CAR22 T-cell cocktail therapy and obtained long-term disease-free survival after autologous hematopoietic stem cells (ASCT) and subsequential CAR19 and CAR22 T-cell cocktail therapy. The clinical evolution and genetic features of this case may provide some guidance for CAR-T therapy in overcoming relapses associated with TP53 gene mutations.

Allogeneic Hematopoietic Cell Transplantation after Chimeric Antigen Receptor T Cell Therapy in Large B Cell Lymphoma

Anti-CD19 chimeric antigen receptor T cell (CAR-T) therapy has transformed the care of patients with relapsed/refractory large B cell lymphoma (LBCL). However, approximately 60% of CAR-T recipients ultimately will experience disease recurrence or progression. Salvage therapies after CAR-T treatment failures are of limited efficacy and have a short duration of response. The objective of the present study was to evaluate the role of allogeneic hematopoietic cell transplantation (allo-HCT) after CAR-T therapy in LBCL patients. This was a multicenter observational study reporting the outcome of 39 adult LBCL patients who underwent allo-HCT following anti-CD19 CAR-T therapy. The median patient age was 47 years (range, 20 to 68 years). HLA-matched sibling, HLA-matched unrelated, and alternative donors were used in 36%, 36%, and 28% of transplantations, respectively. Conditioning regimens were primarily of low or intermediate intensity. Disease status at allo-HCT was complete response in 41%, partial response in 38%, and progressive disease in 21%. Allo-HCT was performed at a median of 127 days (range, 82 to 206 days) after CAR-T therapy. A high incidence of hepatic toxicity (28%), including sinusoidal obstruction syndrome (15.4%; 95% confidence interval; [CI], 6.2% to 28.5%), was observed. The 1-year cumulative incidence of grade II-IV and grade III-IV acute graft-versus-host disease (GVHD) was 38.5% (95% CI, 23.2% to 53.6%) and 15.4% (95% CI, 6.1% to 28.5%), respectively. The 2-year cumulative incidence of moderate-severe chronic GVHD was 11.1% (95% CI, 3.3% to 24.3%). Overall, 2-year nonrelapse mortality and relapse/progression incidence were 26% (95% CI, 13% to 41%) and 43% (95% CI, 27% to 59%), respectively. With a median follow-up of 32 months, the 2-year overall survival (OS) and progression-free survival (PFS) were 45% (95% CI, 31% to 66%) and 31% (95% CI, 19% to 50%), respectively. In multivariable analyses, pre-HCT elevated lactate dehydrogenase level and transformed lymphoma were predictive of OS and PFS, respectively. Our data suggest that allo-HCT after anti-CD19 CAR-T treatment failure is feasible with a relatively promising efficacy but possibly high toxicity rate.

CD19 chimeric antigen receptor T-cell therapy following autologous stem cell transplantation against relapsed or refractory Burkitt lymphoma/leukemia: A case report and literature review

Burkitt lymphoma or leukemia (BL) is a highly aggressive non-Hodgkin lymphoma. Older age (over 60 years old) and the presence of high-risk factors (such as abdominal mass, high levels of the serum lactic dehydrogenase, Ann Arbor stage II-IV and so on) usually predict a poorer outcome. Chimeric antigen receptor T cells (CART) have achieved remarkable success in the treatment of B-cell leukemia and lymphoma. Here, for the first time, we report a 61-year-old, high-risk BL patient with autologous stem cell transplantation (ASCT) bridging therapy prior to CART as consolidation therapy. Our findings demonstrate that the combination of ASCT and CART for BL is safe and feasible.

Impact of cryopreservation on CAR T production and clinical response

Adoptive cell therapy with chimeric antigen receptor (CAR) T cells has become an efficient treatment option for patients with hematological malignancies. FDA approved CAR T products are manufactured in centralized facilities from fresh or frozen leukapheresis and the cryopreserved CAR T infusion product is shipped back to the patient. An increasing number of clinical centers produce CAR T cells on-site, which enables the use of fresh and cryopreserved PBMCs and CAR T cells. Here we determined the effect of cryopreservation on PBMCs and CD19 CAR T cells in a cohort of 118 patients treated with fresh CAR T cells and in several patients head-to-head. Cryopreserved PBMCs, obtained from leukapheresis products, contained less erythrocytes and T cells, but were sufficient to produce CAR T cells for therapy. There was no correlation between the recovery of PBMCs and the transduction efficacy, the number of CAR T cells obtained by the end of the manufacturing process, the in vitro reactivity, or the response rate to CAR T therapy. We could show that CAR T cells cryopreserved during the manufacturing process, stored and resumed expansion at a later time point, yielded sufficient cell numbers for treatment and led to complete remissions. Phenotype analysis including T cell subtypes, chemokine receptor and co-inhibitory/stimulatory molecules, revealed that fresh CAR T cells expressed significantly more TIM-3 and contained less effector T cells in comparison to their frozen counterparts. In addition, fresh CAR T infusion products demonstrated increased in vitro anti-tumor reactivity, however cryopreserved CAR T cells still showed high anti-tumor potency and specificity. The recovery of cryopreserved CAR T cells was similar in responding and non-responding patients. Although fresh CAR T infusion products exhibit higher anti-tumor reactivity, the use of frozen PBMCs as staring material and frozen CAR T infusion products seems a viable option, as frozen products still exhibit high in vitro potency and cryopreservation did not seem to affect the clinical outcome.

Novel lectin-based chimeric antigen receptors target Gb3-positive tumour cells

The link between cancer and aberrant glycosylation has recently become evident. Glycans and their altered forms, known as tumour-associated carbohydrate antigens (TACAs), are diverse, complex and difficult to target therapeutically. Lectins are naturally occurring glycan-binding proteins  that offer a unique opportunity to recognise TACAs. T cells expressing chimeric antigen receptors (CARs) have proven to be a successful immunotherapy against leukaemias, but so far have shown limited success in solid tumours. We developed a panel of lectin-CARs that recognise the glycosphingolipid globotriaosylceramide (Gb3), which is overexpressed in various cancers, such as Burkitt's lymphoma, colorectal, breast and pancreatic. We have selected the following lectins: Shiga toxin's B-subunit from Shigella dysenteriae, LecA from Pseudomonas aeruginosa, and the engineered lectin Mitsuba from Mytilus galloprovincialis as antigen-binding domains and fused them to a well-known second-generation CAR. The Gb3-binding lectin-CARs have demonstrated target-specific cytotoxicity against Burkitt's lymphoma-derived cell lines as well as solid tumour cells from colorectal and triple-negative breast cancer. Our findings reveal the big potential of lectin-based CARs as therapeutical applications to target Gb3 and other TACAs expressed in haematological malignancies and solid tumours.

l-Asparaginase synergizes with etoposide via the PI3K/Akt/mTOR pathway in Epstein-Barr virus-positive Burkitt lymphoma

Burkitt lymphoma (BL) is an aggressive Epstein-Barr virus (EBV)-driven B-cell lymphoma characterized by the translocation and rearrangement of the c-Myc proto-oncogene. High-intensity multidrug chemotherapy regimens have a limited effect on the survival of refractory or relapsed BL patients, mainly owing to the high EBV load and drug resistance. l-asparaginase ( l-Asp) and etoposide (VP-16) play a beneficial role in EBV-related lymphoproliferative diseases; however, their roles and mechanisms in BL remain unclear. In this study, we found that VP-16 inhibited BL cell proliferation and arrested the cell cycle at the G₂ /M phase. It also induced autophagy and activated the extrinsic and intrinsic apoptotic signaling pathways in BL cells. Mechanistically, VP-16 inhibited c-Myc expression and regulated the PI3K/Akt/mTOR signaling pathway. Notably, VP-16 also showed a specific synergistic effect with l-Asp to induce apoptosis in EBV-positive BL cells but not in EBV-negative BL cells. VP-16 combined with l-Asp further inhibited c-Myc expression and downregulated the PI3K/Akt/mTOR signaling pathway. Additionally, we found that VP-16 inhibited the expression of latent membrane protein 1 (LMP1), and in combination with l-Asp further decreased LMP1 expression in Raji cells. Our in vivo data also showed that the dual-drug combination significantly inhibited the growth of BL tumors and prolonged the survival of mice compared to VP-16 alone. In conclusion, this study provides new evidence that l-Asp may enhance the antitumor effect of VP-16 by inhibiting the PI3K/Akt/mTOR signaling pathway in EBV-positive BL cells.

Chimeric Antigen Receptor-Modified T Cell Immunotherapy for Relapsed and Refractory Adult Burkitt Lymphoma

Patients with Burkitt lymphoma who are refractory to initial therapy or who relapse after undergoing intensive chemotherapy and autologous stem cell transplantation (ASCT) usually have a poor prognosis. While there has been considerable progress in the use of chimeric antigen receptor-modified (CAR) T cell immunotherapy for the treatment of relapsed and refractory (r/r) malignancies, explicit data on adult patients with r/r Burkitt lymphoma are limited. We conducted two single-arm clinical trials to evaluate the clinical efficacy and toxicity of CD19/CD22 CAR T cell immunotherapy both alone (trial A) and in combination with ASCT (trial B) in adult patients with r/r Burkitt lymphoma. In total, 28 adult patients with r/r Burkitt lymphoma were enrolled [trial A (n = 15) and trial B (n = 13)]. The median doses of CD22 and CD19 CAR T cell infusions were 4.1 × 10⁶/kg and 4.0 × 10⁶/kg, respectively. Subsequently, after CAR T cell infusion, overall and complete responses were observed in 19 (67.9%) and 16 (57.1%) patients, respectively. The cumulative incidence rates of grade 2–4 cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome were 39.3% (11/28) and 10.7% (3/28), respectively. After a median follow-up duration of 12.5 months, 16 patients (5 in trial A and 11 in trial B) survived. Both the estimated 1-year progression-free and overall survival rates were 55.6%. Our preliminary results indicated that salvage therapy with CD19/CD22 CAR T cell infusion alone and that in combination with ASCT are effective in treating some adult patients with r/r Burkitt lymphoma.

Gp350-anchored extracellular vesicles: promising vehicles for delivering therapeutic drugs of B cell malignancies

Although chimeric antigen receptor-modified (CAR) T cell therapy has been successfully applied in the treatment of acute B lymphocytic leukemia, its effect on Burkitt lymphoma (BL) and chronic B lymphocytic leukemia (B-CLL) is unsatisfactory. Moreover, fatal side effects greatly impede CAR T cell application. Extracellular vesicles (EVs) are excellent carriers of therapeutic agents. Nevertheless, EVs mainly accumulate in the liver when administered without modification. As an envelope glycoprotein of Epstein-Barr viruses, gp350 can efficiently bind CD21 on B cells. Here, gp350 was directly anchored onto red blood cell EVs (RBC-EVs) via its transmembrane region combined with low-voltage electroporation. The results showed that gp350 could anchor to RBC-EVs with high efficiency and that the resulting gp350-anchored RBC-EVs (RBC-EVs/gp350Etp) exhibited increased targeting to CD21+ BL and B-CLL relative to RBC-EVs. After the loading of doxorubicin or fludarabine, RBC-EVs/gp350Etp had powerful cytotoxicity and therapeutic efficacy on CD21+ BL or B-CLL, respectively. Moreover, RBC-EVs/gp350Etp loaded with a drug did not exhibit any apparent systemic toxicity and specifically induced the apoptosis of tumor B cells but not normal B cells. Therefore, our findings indicate that drug-loaded RBC-EVs/gp350Etp may be adopted in the treatment of CD21+ B cell malignancies.

Point-of-care anti-CD19 CAR T-cells for treatment of relapsed and refractory aggressive B cell lymphoma

BACKGROUND

Anti CD19 Chimeric Antigen Receptor (CAR) T-cell therapy has transformed the care of relapsed & refractory aggressive B cell Lymphoma. However, financial toxicity and manufacturing time represent barriers to its widespread implementation.

OBJECTIVE

Study applicability, toxicity, and efficacy of a locally produced autologous CD19-directed CAR-T cell product.

METHODS

We performed a phase 1b/2 clinical trial with a point-of-care (POC) CAR T-cell product that contains a CD28 costimulatory domain. Adult patients with aggressive B cell lymphoma or transformed low-grade lymphoma who received at least two prior regimens were eligible.

RESULTS

A total of 73 patients, with a median age of 49 years, met inclusion criteria. CAR-T production time from apheresis was 10 days (IQR 10-11), negating the need for bridging chemotherapy. Overall and complete response rates were 62.5% and 37.5%. Median progression-free and overall survival were 3.7 and 12.1 months, respectively. Overall and progression-free survival at 12 months were 52.1% (CI: 40.8%-66.5%) and 40% (CI: 30%-53.7%), respectively. Patients who achieved response had longer progression-free and overall survival. Grade 3-4 CRS was observed in 9.5% of the patients, and ICANS grade 3-4 in 21.9%. No deaths occurred due to CAR T-cell toxicity. Fifteen patients (20%) underwent allogeneic stem cell transplantation at a median time of 60 days post CAR T-cell therapy; 8 were alive at last follow-up. Of the six patients that underwent the transplant in complete response 2 deceased due to toxicity.

CONCLUSIONS

POC CAR-T cells are a feasible therapeutic option in aggressive B-cell lymphoma. They provide good efficacy while minimizing production time and the need for bridging therapy.

The treatment of Burkitt lymphoma in adults

Burkitt lymphoma (BL) is a highly aggressive, B-cell, non-Hodgkin lymphoma categorized into endemic, sporadic, and immunodeficiency-associated subtypes. BL has distinct pathologic and clinical features, characterized by rapidly progressive tumors with high rates of extranodal involvement. Next-generation-sequencing analyses have further characterized the genomic landscape of BL and our understanding of disease pathogenesis, although these findings have yet to influence treatment. Although most patients are cured with intensive combination chemotherapy, given the paucity of randomized trials, optimal therapy has not been defined. Furthermore, treatment of elderly patients, patients with central nervous system involvement, or those with relapsed disease remains an unmet need. In this review, we highlight the clinical, pathologic, and genomic features, as well as standard and emerging treatment options for adult patients with BL.

Novel Biological Insights and New Developments in Management of Burkitt Lymphoma and High-Grade B-Cell Lymphoma

OPINION STATEMENT

Burkitt lymphoma (BL) is highly curable, and prompt institution of therapy is critical to achieving optimal outcomes. Although current "standard" approaches are very effective in disease eradication, treatment-related toxicity makes optimal delivery of curative therapy a challenge, especially in older and immunocompromised individuals. Reduced intensity approaches with fewer toxic complications have been the focus of some recent studies. A critical question is if they can replace "standard" approaches by maintaining high curability with improved tolerability. Additionally, new molecular insights in BL biology suggest that in the future, "targeted therapy" approaches may be feasible using small molecule inhibitors and novel strategies. Recently, a new category of aggressive lymphoma named "high-grade B-cell lymphoma (HGBL) with MYC and BCL2 and/or BCL6 translocations" has been recognized. This category overlaps clinically and biologically with BL and has an inferior prognosis compared to most B-cell lymphomas, and the optimal approach to its management remains, as yet, undefined. In this review, we discuss the current landscape of BL treatment including recent results with low-intensity regimens and also consider current approaches to HGBL. We also explore how recently elucidated novel biological insights in BL biology may shape future therapeutic directions including the use of novel cellular therapy approaches.

Successful Treatment of Pediatric Refractory Burkitt Lymphoma PTLD after Liver Transplantation using Anti-CD19 Chimeric Antigen Receptor T-Cell Therapy

In the immunocompromised setting, recipients of solid-organ or hematopoietic stem-cell transplants carry an increased risk of post-transplant lymphoproliferative disorder (PTLD). Burkitt lymphoma (BL) PTLD is a rare form of monomorphic B-cell PTLD, which lacks a standard best treatment. Here, we report the successful treatment of refractory BL-PTLD with autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy. A male patient was diagnosed with BL-PTLD, with an increasing Epstein-Barr virus (EBV) viral load, at 21 months after undergoing living liver transplantation from his mother due to neonatal biliary atresia. After 10 cycles rituximab +/- intensive chemotherapy and surgical tumor resection, the tumors significantly advanced. Next-generation sequencing (NGS) was performed on formalin-fixed paraffin-embedded tumor tissue, revealing one mutation in exon 5, TP53: p.A159 V, which may be associated with chemo-resistance. Thus, treatment was started with autologous anti-CD19 CAR T-cell therapy. We administered 9.0 × 10⁶/kg autologous anti-CD19 CAR T-cells, after conditioning with cyclophosphamide and fludarabine. Unexpectedly, the patient experienced only mild (Grade II) cytokine release syndrome (CRS) without neurotoxicity. Finally, he went into complete remission (CR), and has achieved 16-month event-free survival to date. In addition, liver function has remained stably within the normal range without any immunosuppressive therapy. The literature includes only five previously reported BL cases treated with CAR T-cell therapy. In conclusion, the present case suggests that autologous anti-CD19 CAR T-cell therapy may represent a new therapeutic option for some cases of refractory BL-PTLD.Clinical trial number: ChiCTR2000032211.

CAR19/22 T cell therapy in adult refractory Burkitt's lymphoma

The treatment of refractory Burkitt's lymphoma (BL) is still a challenge. Although CAR-T cell therapy has achieved good responses in diffuse large B cell lymphoma, there is no case series report about the efficacy of CAR-T cell therapy in adult Burkitt's lymphoma. In this study, we evaluate the efficacy and safety of CAR19/22 T cell therapy in six refractory Burkitt's lymphoma cases with poor genetic prognostic factors. After CAR-T cell therapy, five cases had grade 1 and one had grade 3 cytokine release syndrome. Three patients achieved an objective response (3/6 50%), including two partial remission and one complete remission. One CR patient received allogeneic hematopoietic stem cell transplantation (HSCT) and one PR patient received CAR22/19-T cells following auto-HSCT, and they were still in remission at 37 and 22 months of follow-up, respectively. Interestingly, patients with bulky disease (case 2, 4 and 5) had higher levels of serum IL-2R, which was secreted by regulatory T cells, lower CAR lentiviral amplification and poorer prognosis with shorter survival time than cases with non-bulky disease. It is suggested that high tumor burden, more immune suppressive cells and limited CAR-T cell expansion might affect the efficacy of CAR-T cell therapy. CAR-T cell therapy in adult BL patients whose best response cannot achieve CR may need to bridge to other treatments (such as HSCT) early.

Chimeric antigen receptor T cells for mature B-cell lymphoma and Burkitt lymphoma

Chimeric antigen receptor (CAR) T-cell therapy has changed the landscape of immunotherapy for B-cell malignancies, including mature B-cell lymphomas. Although two CD19 CAR T-cell products have been commercially approved to treat relapsed/refractory B-cell lymphomas, outcomes in these patients remain inferior to those of patients with B-cell leukemia, regardless of therapy. Recent clinical studies and preclinical reports suggest that certain characteristics, such as the suppressive lymphoma tumor microenvironment and inferior endogenous T-cell fitness, may contribute to discrepant responses in these patients. In addition, these studies revealed that limited CAR T-cell persistence and tumor antigen escape, which also impact B-cell acute lymphoblastic leukemia, may play a more prominent role in lymphoma. Multiple promising strategies to overcome these barriers have advanced to clinical trials. In this review, we assess CAR T-cell therapies for pediatric relapsed/refractory mature B-cell lymphomas, potential obstacles diminishing antitumor activity and limiting CAR T-cell persistence, and current strategies to overcome these obstacles.

A giant step forward: chimeric antigen receptor T-cell therapy for lymphoma

The combination of the immunotherapy (i.e., the use of monoclonal antibodies) and the conventional chemotherapy increases the long-term survival of patients with lymphoma. However, for patients with relapsed or treatment-resistant lymphoma, a novel treatment approach is urgently needed. Chimeric antigen receptor T (CAR-T) cells were introduced as a treatment for these patients. Based on recent clinical data, approximately 50% of patients with relapsed or refractory B-cell lymphoma achieved complete remission after receiving the CD19 CAR-T cell therapy. Moreover, clinical data revealed that some patients remained in remission for more than two years after the CAR-T cell therapy. Other than the CD19-targeted CAR-T, the novel target antigens, such as CD20, CD22, CD30, and CD37, which were greatly expressed on lymphoma cells, were studied under preclinical and clinical evaluations for use in the treatment of lymphoma. Nonetheless, the CAR-T therapy was usually associated with potentially lethal adverse effects, such as the cytokine release syndrome and the neurotoxicity. Therefore, optimizing the structure of CAR, creating new drugs, and combining CAR-T cell therapy with stem cell transplantation are potential solutions to increase the effectiveness of treatment and reduce the toxicity in patients with lymphoma after the CAR-T cell therapy.

Head-to-head comparison of in-house produced CD19 CAR-T cell in ALL and NHL patients

Background

CD19 chimeric antigen receptor T (CAR-T) cells demonstrate remarkable remission rates in pediatric and adult patients with refractory or relapsed (r/r) acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). In 2016, we initiated a clinical trial with in-house produced CD19 CAR-T cells with a CD28 co-stimulatory domain. We analyzed, for the first time, differences in production features and phenotype between ALL and NHL patients.

Methods

Non-cryopreserved CAR-T cells were produced from patients’ peripheral blood mononuclear cells within 9 to 10 days. 93 patients with r/r ALL and NHL were enrolled under the same study. CAR-T cells of ALL and NHL patients were produced simultaneously, allowing the head-to-head comparison.

Results

All patients were heavily pretreated. Three patients dropped out from the study due to clinical deterioration (n=2) or production failure (n=1). Cells of ALL patients (n=37) expanded significantly better and contained more CAR-T cells than of NHL patients (n=53). Young age had a positive impact on the proliferation capacity. The infusion products from ALL patients contained significantly more naïve CAR-T cells and a significantly higher expression of the chemokine receptor CXCR3. PD-1, LAG-3, TIM-3, and CD28 were equally expressed. 100% of ALL patients and 94% of NHL patients received the target dose of 1×10e6 CAR-T/kg. The overall response rate was 84% (30/36) in ALL and 62% (32/52) in NHL. We further compared CAR-T cell infusion products to tumor infiltrating lymphocytes (TIL), another common type of T cell therapy, mainly clinically effective in solid tumors. CAR-T cells contained significantly more naïve T cells and central memory T cells and significantly less CCR5 compared to TIL infusion products.

Conclusions

The in-house production of CAR-T cells is highly efficient and fast. Clinical response rate is high. CAR-T cells can be successfully produced for 99% of patients in just 9 to 10 days. Cells derived from ALL patients demonstrate a higher proliferation rate and contain higher frequencies of CAR-T cells and naïve T cells than of NHL patients. In addition, understanding the differences between CAR-T and TIL infusion products, may provide an angle to develop CAR-T cells for the treatment of solid tumors in the future.

Trial registration number

ClinicalTrials.gov; CAR-T: NCT02772198, First posted: May 13, 2016; TIL: NCT00287131, First posted: February 6, 2006.

HIV-associated Burkitt lymphoma

Burkitt lymphoma is a rare and aggressive non-Hodgkin lymphoma with three classifications: endemic, sporadic, and immunodeficiency-related. High-intensity chemotherapeutic regimens have considerably improved overall survival for patients with Burkitt lymphoma. In this Review of HIV-associated Burkitt lymphoma, we summarise expert opinion and provide general recommendations for the treatment of Burkitt lymphoma in patients with HIV on the basis of retrospective and prospective studies, taking into consideration immune status, CD4 cell counts, the presence of systemic disease, and the risk of CNS involvement or relapse. We also discuss the role of rituximab and antiretroviral therapy. We highlight the reasons behind the possible different mechanisms of lymphomagenesis in HIV-associated Burkitt lymphoma and endemic Burkitt lymphoma, which indicate that HIV might have either a direct or indirect oncogenic role in Burkitt lymphoma. We discuss the possible mechanisms by which HIV and HIV proteins could directly contribute to lymphomagenesis. Identifying these mechanisms might lead to the development of therapies that have fewer toxic effects than high-intensity chemotherapeutic regimens.

Burkitt lymphoma: bridging the gap between advances in molecular biology and therapy

Genomic studies have revealed molecular mechanisms involved in the pathogenesis of Burkitt's lymphoma, including the ID3/TCF3-dependent centroblast gene expression program, tonic PI3K-AKT-mTOR signaling, and deregulation of cell cycle and apoptosis through mutations in cyclin D3, CDKN2A, or TP53. Unfortunately, these advances have not been translated into treatment, which relies on dose-intense cytotoxic chemotherapy. While most patients achieve long-term survival, options for relapsed/refractory disease are lacking, as Burkitt lymphoma is often excluded from clinical trials of novel approaches. The lower-intensity, dose-adjusted EPOCH plus rituximab (DA-EPOCH-R) regimen constitutes a major advance allowing for treatment of older and HIV-positive patients but needs augmentation to better address the central nervous system involvement. Furthermore, DA-EPOCH-R provides a platform for the study of targeted or immunotherapeutic approaches while de-escalating cytotoxic agents and their associated adverse effects. In this review we discuss the epidemiology and molecular genetics of BL, first-line treatment considerations, and potential novel treatment strategies.