Safety and preliminary efficacy in patients (pts) with relapsed/refractory (R/R) mantle cell lymphoma (MCL) receiving lisocabtagene maraleucel (Liso-cel) in TRANSCEND NHL 001

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Background: Most pts with MCL relapse after first-line immunochemotherapy, with poor responses to salvage therapy. We report initial dose-finding results from pts with R/R MCL treated with liso-cel (JCAR017), an investigational, anti-CD19 CAR T cell product administered as a defined composition of CD4+/CD8+ CAR T cells, in the ongoing phase 1 TRANSCEND study. Methods: Eligible pts had confirmed MCL (cyclin D1 expression, t[11;14]) with R/R disease after ≥1 prior lines of therapy. After lymphodepleting chemotherapy, liso-cel was administered at 1 of 2 dose levels (DL): DL1 = 50 × 106 or DL2 = 100 × 106 total CAR+ T cells. Results: At data cutoff, 9 pts (DL1, n = 6; DL2, n = 3) had received liso-cel. The median (range) age was 66 (58‒78) years; 7 pts were male. Histologies included blastoid (n = 3) and pleiomorphic (n = 1) variants. 8 pts had documented Ki67 > 30% (40%‒80%); 1 pt had TP53 mutation. Pts had received a median of 5 (3‒7) prior therapies; 3 pts had received prior hematopoietic stem cell transplant. All 9 pts had prior ibrutinib; 4 had a best response of progressive disease on ibrutinib. 6/9 pts (67%) received bridging chemotherapy. 4/9 pts (44%) had serious treatment-emergent adverse events (TEAEs). 5/9 pts (56%) had grade (G) 3/4 TEAEs, primarily anemia, neutropenia, and hypophosphatemia (22% each). 3/9 pts (33%) had cytokine release syndrome (CRS); all were G1. Median time to CRS onset was 6 (2‒7) days; median time to resolution was 6 (2‒6) days. 1 pt received tocilizumab and corticosteroids. There were no neurological events. 4 pts died, all in DL1 (3 from disease progression; 1 after receiving new anticancer therapy post liso-cel). Overall response rate was 78% (7/9 pts; 4/6 in DL1, median follow-up 12.4 [95% CI: 9.2–12.4] mo; 3/3 in DL2, median follow-up 1.4 [95% CI: 1.0–1.4] mo). 2 pts in DL1 maintained a durable CR until last follow-up (day 281 and 378, respectively). Median time to peak CAR+ T cell expansion: 9.5 (9–10) days at DL1 and 17.5 (10–27) days at DL2. Conclusions: In this phase 1 study in pts with R/R MCL, liso-cel treatment showed tolerable toxicity and had clinical activity. Updated DL2 data and longer follow-up will be presented. Clinical trial information: NCT02631044.

Management of cytokine release syndrome and neurotoxicity in chimeric antigen receptor (CAR) T cell therapy

INTRODUCTION

Chimeric antigen receptor (CAR) T cell immunotherapy has demonstrated remarkable anti-tumor activity in B-cell malignancies and is under investigation in other hematologic malignancies and solid tumors. While highly efficacious, post-infusion T cell activity often results in massive cytokine release precipitating cytokine release syndrome (CRS), the signature toxicity of CAR T cells. This toxicity is characterized by systemic immune activation resulting in fever, hypotension, respiratory insufficiency and capillary leak. Either in conjunction with or in the absence of CRS, a subset of patients may also develop mild to severe neurotoxicity. Although the precise pathogenesis of CRS and neurotoxicity aren't fully elucidated, risk factors and mitigation strategies have been reported. Areas covered: This manuscript provides an in-depth overview of the pathogenesis, clinical characteristics, current toxicity management strategies, and future perspectives pertaining to CRS and neurotoxicity. Expert Opinion: As CAR T cell based therapies gain popularity in the management of various malignancies, the complimentary toxicities of CRS and neurotoxicity pose a clinical challenge in practice. Risk adaptive modeling incorporating disease profile, patient demographics, lymphodepletion, cell dosing, CAR T construct, and potentially cytokine gene polymorphisms may be instructive to assess individualized risk and optimal CRS/neurotoxicity management.

Factors affecting lymphocyte collection efficiency for the manufacture of chimeric antigen receptor T cells in adults with B-cell malignancies

BACKGROUND

The clinical and procedural parameters that affect the optimal collection of lymphocytes for the production of chimeric antigen receptor (CAR) T cells remain undefined but are increasingly important, as commercial products are now available. We evaluated determinants of low lymphocyte collection efficiency (CE) and the rate of successful CAR T-cell manufacture in middle-aged and older adults with advanced B-cell malignancies.

STUDY DESIGNS AND METHODS

Mononuclear cell collections using two apheresis platforms (COBE Spectra and Spectra Optia, Terumo BCT) from patients participating in a CD19-directed CAR T-cell therapy trial were reviewed. Patient- and disease-specific factors, peripheral blood counts, apheresis parameters, and product cell counts were analyzed to determine effects on lymphocyte CE.

RESULTS

Ninety-two apheresis events from patients with acute lymphocytic leukemia (ALL) (n = 28), chronic lymphocytic leukemia (n = 18), and non-Hodgkin lymphoma (n = 46) were available for analysis. Forty-one collections (45%) had a lymphocyte CE of <40%. On multivariable analysis, age (every 10-year increase, odds ratio [OR] = 1.51; p = 0.034), disease type (chronic lymphocytic leukemia vs. ALL, OR = 0.24; p = 0.052; non-Hodgkin lymphoma vs. ALL, OR = 0.20; p = 0.009) and precollection platelets (every 10 × 10³ /μL increase, OR = 1.07; p = 0.005) were appreciably associated with a lymphocyte CE of <40%. No major apheresis complications occurred.

CONCLUSIONS

Lymphocyte collection at our center was well tolerated and 100% successful in manufacturing CD19-directed CAR T cells from adult patients with B-cell malignancies despite low CE in some patients. A diagnosis of ALL, advancing age, and higher preapheresis platelet counts were observed to be associated with low CE.

Second allogeneic hematopoietic cell transplantation for relapse after first allografts

We analyzed outcomes of 126 patients with hematologic malignancies, who relapsed after first allogeneic hematopoietic cell transplantation (HCT) and received subsequent allografts. In 17 cases, the original donors were utilized, while in 109 cases different donors were identified. The 2-year overall survival (OS), relapse, and non-relapse mortality (NRM) rates were 33%, 42%, and 33%, respectively. Patients with early relapse after first allogeneic HCT (within 100 days vs. 100 days to 12 months vs. >12 months) had higher relapse rates (50% vs. 47% vs. 34%, respectively; p = .01) and worse OS (15% vs. 25% vs. 45%, respectively, p = .005) at 2 years after second allogeneic HCT. In conclusion, second allogeneic HCT should be considered in patients who relapse after first allografts, especially in those who relapse after more than a year. Utilizing a different donor for the second allotransplant including umbilical cord blood or HLA-haploidentical, related donors did not adversely impact outcomes.

Total body irradiation dose escalation decreases risk of progression and graft rejection after hematopoietic cell transplantation for myelodysplastic syndromes or myeloproliferative neoplasms

A non-myeloablative regimen of fludarabine and 200 cGy total body irradiation combined with post-grafting immunosuppression with mycophenolate mofetil and a calcineurin inhibitor facilitates allogeneic hematopoietic cell transplantation from HLA-matched related or unrelated donors in older patients and/or those with comorbidities. However, outcomes of prior studies have been disappointing in patients with myelodysplastic syndromes or myeloproliferative neoplasms due to high incidences of progression or graft failure (together termed hematopoietic cell transplantation-failure). We hypothesized that escalating the total body irradiation dose may improve the outcomes and subsequently performed a phase II total body irradiation dose-escalation trial. Patients with median age 66 years were enrolled in two arms to receive non-myeloablative conditioning followed by hematopoietic cell transplantation with total body irradiation dose escalation for excessive hematopoietic cell transplantation-failure: Arm A: myeloproliferative neoplasm/myelodysplastic syndrome low risk (n=36); and Arm B: myelodysplastic syndrome high-risk/chronic myelomonocytic leukemia (n=41). Total body irradiation dose levels were: Level-1 (300 cGy), Level-2 (400 cGy), or Level-3 (450 cGy). Patients received intravenous fludarabine 30 mg/m² for three days. Total body irradiation was administered on day 0 followed by infusion of peripheral blood stem cells from HLA-matched related (n=30) or unrelated (n=47) donors. Post-grafting immunosuppression with mycophenolate mofetil and cyclosporine was administered. The primary end point was day 200 hematopoietic cell transplant failure, with the objective of reducing the incidence to <20%. The primary end point was reached on Arm A at dose Level-1 (300 cGy total body irradiation) with a cumulative incidence of day 200 hematopoietic cell transplant failure of 11%, and on Arm B at dose Level-3 (450 cGy) with a cumulative incidence of day 200 hematopoietic cell transplant failure of 9%. Increasing the total body irradiation dose leads to a higher success rate with non-myeloablative conditioning by reducing relapse and rejection. Further studies are necessary to decrease non-relapse mortality, especially among patients with high-risk disease. Trial registered under clinicaltrials.gov identifier: NCT00397813.

Chimeric antigen receptor (CAR) T therapies for the treatment of hematologic malignancies: clinical perspective and significance

Chimeric Antigen Receptor (CAR) T cell therapies - adoptive T cell therapies that have been genetically engineered for a new antigen-specificity - have displayed significant success in treating patients with hematologic malignancies, leading to three recent US Food and Drug Administration approvals. Based on the promise generated from these successes, the field is rapidly evolving to include new disease indications and CAR designs, while simultaneously reviewing and optimizing toxicity and management protocols. As such, this review provides expert perspective on the significance and clinical considerations of CAR T cell therapies in order to provide timely information to clinicians about this revolutionary new therapeutic class.

Long-Term Follow-Up of 90Y-Ibritumomab Tiuxetan, Fludarabine, and Total Body Irradiation-Based Nonmyeloablative Allogeneic Transplant Conditioning for Persistent High-Risk B Cell Lymphoma

Nonmyeloablative allogeneic hematopoietic cell transplantation (HCT) can provide prolonged remissions in patients with advanced B cell lymphoma (B-NHL) via the graft-versus-lymphoma effect, although inferior results are seen in patients with chemoresistant, bulky, or aggressive disease. Radioimmunotherapy can safely induce responses in B-NHL with minimal nonhematologic toxicity. Initial results of 90Y-ibritumomab tiuxetan-based allografting demonstrated early safety and disease control in nonremission patients but with short follow-up. Here we report the long-term outcomes of patients treated on this study with specific emphasis on patients achieving early remissions. Eleven of 40 patients were alive at a median follow-up of 9 years (range, 5.3 to 10.2). Fourteen (35%) deaths were due to disease progression and 14 (35%) deaths to complications from HCT. One patient died of a Merkel cell carcinoma. The 5-year overall and progression-free survival for patients with indolent B-NHL was 40% and 27.5%, respectively. None of the patients with diffuse large B cell lymphoma was a long-term disease-free survivor regardless of early remission status. 90Y-ibritumomab tiuxetan-based allografting represents a viable option in patients with indolent histologies. Improved strategies are needed for aggressive B-NHL. The original trial was registered at www.clinicaltrials.gov as NCT00119392.

Long-term follow up of tandem autologous-allogeneic hematopoietic cell transplantation for multiple myeloma

We previously reported initial results in 102 multiple myeloma (MM) patients treated with sequential high-dose melphalan and autologous hematopoietic cell transplantation followed by 200 cGy total body irradiation with or without fludarabine 90 mg/m² and allogeneic hematopoietic cell transplantation. Here we present long-term clinical outcomes among the 102 initial patients and among 142 additional patients, with a median follow up of 8.3 (range 1.0-18.1) years. Donors included human leukocyte antigen identical siblings (n=179) and HLA-matched unrelated donors (n=65). A total of 209 patients (86%) received tandem autologous-allogeneic upfront, while thirty-five patients (14%) had failed a previous autologous hematopoietic cell transplantation before the planned autologous-allogeneic transplantation. Thirty-one patients received maintenance treatment at a median of 86 days (range, 61-150) after allogeneic transplantation. Five-year rates of overall survival (OS) and progression-free survival (PFS) were 54% and 31%, respectively. Ten-year OS and PFS were 41% and 19%, respectively. Overall non-relapse mortality was 2% at 100 days and 14% at five years. Patients with induction-refractory disease and those with high-risk biological features experienced shorter OS and PFS. A total of 152 patients experienced disease relapse and 117 of those received salvage treatment. Eighty-three of the 117 patients achieved a clinical response, and for those, the median duration of survival after relapse was 7.8 years. Moreover, a subset of patients who became negative for minimal residual disease (MRD) by flow cytometry experienced a significantly lower relapse rate as compared with MRD-positive patients (P=0.03). Our study showed that the graft-versus-myeloma effect after non-myeloablative allografting allowed long-term disease control in standard and high-risk patient subsets. Ultra-high-risk patients did not appear to benefit from tandem autologous/allogeneic hematopoietic cell transplantation because of early disease relapse. Incorporation of newer anti-MM agents into the initial induction treatments before tandem hematopoietic cell transplantation and during maintenance might improve outcomes of ultra-high-risk patients. Clinical trials included in this study are registered at: clinicaltrials.gov identifiers: 00075478, 00005799, 01251575, 00078858, 00105001, 00027820, 00089011, 00003196, 00006251, 00793572, 00054353, 00014235, 00003954.

Continued Excellent Outcomes in Previously Untreated Patients With Follicular Lymphoma After Treatment With CHOP Plus Rituximab or CHOP Plus 131I-Tositumomab: Long-Term Follow-Up of Phase III Randomized Study SWOG-S0016

Purpose SWOG S0016 was a phase III randomized study that compared the safety and efficacy of R-CHOP (rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone) with CHOP-RIT (CHOP followed by consolidation with iodine-133-tositumomab radioimmunotherapy) for previously untreated patients with follicular lymphoma. Understanding the long-term outcome of patients provides a benchmark for novel treatment regimens for FL. Patients and Methods Between 2001 and 2008, 531 previously untreated patients with FL were randomly assigned to receive either six cycles of R-CHOP or six cycles of CHOP-RIT. Patients with advanced-stage disease (bulky stage II, III, or IV) of any pathologic grade (1, 2, or 3) were eligible. Results After a median follow-up of 10.3 years, 10-year estimates of progression-free and overall survival were 49% and 78% among all patients, respectively. Patients in the CHOP-RIT arm had significantly better 10-year progression-free survival compared with patients in the R-CHOP arm (56% v 42%; P = .01), but 10-year overall survival was not different between the two arms (75% v 81%; P = .13). There was no significant difference between the CHOP-RIT and R-CHOP arms in regard to incidence of second malignancies (15.1% v 16.1%; P = .81) or myelodysplastic syndrome or acute myeloid leukemia (4.9% v 1.8%; P = .058). The estimated 10-year cumulative incidences of death resulting from second malignancies were not different (7.1% v 3.2%; P = .16), but cumulative incidence of death resulting from myelodysplastic syndrome or acute myeloid leukemia was higher in the CHOP-RIT arm compared with the R-CHOP arm (4% v 0.9%; P = .02). Conclusion Given these outstanding outcomes, immunochemotherapy should remain the standard induction approach for patients with high-risk FL until long-term follow-up of alternative approaches demonstrates superiority.

Correlation of patient characteristics and biomarkers with clinical outcomes of JCAR017 in R/R aggressive B-NHL (TRANSCEND NHL 001 study)

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Background: JCAR017 is a defined composition, CD19-directed 4-1BB CAR T cell product administered at a precise dose of CD8 and CD4 CAR T cells in a seamless design Ph1 pivotal trial of R/R B-cell NHL (TRANSCEND NHL 001; NCT02631044). Methods: Blood samples were collected for biomarker analyses at protocol-defined time points. PK (CAR T cell expansion and persistence) was measured using flow cytometry. Cytokines were measured on a Luminex platform. Additional analytes will be presented. All reported p-values are 2-sided without multiplicity adjustment. Results: Safety (n = 59) and efficacy (n = 54) outcomes were analyzed for correlations with patient (pt) characteristics and biomarkers. Dose level did not correlate with cytokine release syndrome (CRS) or neurotoxicity (NT) despite higher median Cmax and median AUC0-28 at DL2. In pts with NT or ≥Gr 2 CRS, CD4 and CD8 CAR T cell levels were 5-10 fold and 3-5 fold higher, respectively, than median DL2 levels. Pt factors that correlated with any grade CRS and NT were ECOG 2 (p = 0.03) and high disease burden (p < 0.05). Higher levels of IL-8, IL-10, and CXCL10 before CART cell infusion were associated with Gr 3-4 NT (each p< 0.05), suggesting that inherent pt factors may result in higher CAR T expansion and associated CRS and NT. Lower pre-CAR T cell ferritin, LDH, CXCL10, G-CSF, and IL-10 were associated with CR/PR, and lower pre-CAR T cell ferritin, CRP, LDH, CXCL10, IL-8, IL-10, IL-15, MCP-1, MIP-1β, TNF-α were associated with 3-month durable response (each p< 0.05). Median Cmax and AUC0-28 of CD8 CAR T cells were higher in responding patients and with durable response at Month 3 (CD8 Cmax median = 20.8 vs 5.5; CD8 AUC median = 235 vs 55 in CR/PR vs PD at Month 3). Of pts evaluable for persistence at 3 months (n = 29), 90% and 93% had detectable CD8+ and CD4+ CAR+ T cells; of those with available PK results at time of relapse (n = 11), 82% had persistence at time of relapse. Conclusions: JCAR017 demonstrated increased CAR T cell expansion and persistence and higher durability of response at higher dose levels, with manageable toxicities. CAR T cells were also detected at time of relapse, suggesting potential opportunities for future combination clinical trials. Clinical trial information: NCT02631044.

Phase I study of immunotherapy for advanced ROR1+ malignancies with autologous ROR1-specific chimeric antigen receptor-modified (CAR)-T cells

TPS79

Background: CAR-T cells have demonstrated marked tumor regression in patients (pts) with hematologic malignancies. ROR1, a tyrosine kinase orphan receptor, is expressed in triple negative breast cancers (TNBC) and non-small cell lung cancers (NSCLC) and is a novel candidate for CAR-T cell therapy. ROR1-specific CAR-T cells are engineered with lentiviral vector encoding ROR1 scFv/4-1BB/CD3ζ and a truncated EGFR molecule to permit elimination of ROR1 CAR-T cells in case of toxicity. Methods: NCT02706362 is a phase I study evaluating the safety and anti-tumor activity of adoptively transferred autologous ROR1 CAR-T cells in pts with advanced ROR1+ TNBC and NSCLC. Eligibility criteria include: metastatic TNBC or NSCLC; measurable disease; prior standard therapy with no maximum on number of prior regimens; tumor ROR1 expression > 20% by IHC; KPS > 70%; age ≥18; negative pregnancy test for women of childbearing potential; informed consent; adequate organ function. Exclusions are: active autoimmune disease or uncontrolled infection, HIV seropositive status, contraindication to cyclophosphamide, anticipated survival < 3 months, and/or untreated CNS metastases. After screening, leukapheresis is performed, CD8+ and CD4+ T cells are selected, then transduced with the ROR1+ CAR lentivirus and expanded. Lymphodepletion with cyclophosphamide and fludarabine is followed 36-96 hours later by infusion of ROR1 CAR-T cells in escalating doses (3.3 x 105/kg - 1 x 107/kg cells with defined CD8+ and CD4+ composition). Pts are treated in cohorts of 2 to determine cell dose associated with an estimated toxicity rate of < 25%. Primary aim is to determine the maximum tolerated dose (MTD) and safety of ex vivo expanded ROR1 CAR-T cells. Secondary aims include persistence and phenotype of transferred T cells, trafficking of T cells to tumor site, in vivo function, and preliminary antitumor activity of ROR1 CAR-T cells by RECIST 1.1. Dose escalation is determined by CRM algorithm with minimum of 21-day interval following infusion between pts. Preliminary estimates of efficacy will be obtained among all pts and those treated at estimated MTD. Six of 30 pts have been enrolled with no DLTs observed. Clinical trial information: NCT02706392.

High durable CR rates and preliminary safety profile for JCAR017 in R/R aggressive b-NHL (TRANSCEND NHL 001 Study): A defined composition CD19-directed CAR T-cell product with potential for outpatient administration

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Background: JCAR017 is a defined composition, CD19-directed 4-1BB CAR T cell product administered at a precise dose of CD8 and CD4 CAR T cells in a seamless design Phase 1 pivotal trial of relapsed/refractory (R/R) B-cell NHL (TRANSCEND NHL 001; NCT02631044). Methods: Patients (pts) with R/R DLBCL NOS, PMBCL, FL grade 3B, or MCL and adequate organ function are eligible. The FULL dataset includes all pts in the DLBCL cohort (i.e. excludes MCL). The CORE dataset includes pts meeting inclusion for a planned pivotal DLBCL cohort (DLBCL NOS [ de novo or transformed from follicular lymphoma], ECOG 0-1, no prior allo-SCT). Results: As of July 7, 2017, 69 pts were treated in the DLBCL cohort and evaluable for safety. In the FULL dataset, 21 pts (30%) had cytokine release syndrome (CRS), with 1 serious CRS event (1%; Gr 4). Neurotoxicity (NT) at any grade developed in 14 (20%), including 10 (14%) with Gr 3-4 events. There were no Gr 5 CRS or NT events. Median time to onset of first CRS and NT was 5 days and 10 days, respectively, 13 (19%) received anti-cytokine therapy and only one required vasopressor support. In the CORE dataset (n = 49), similar rates of CRS and NT were shown. The majority of pts, 64% (44/69), had no CRS or NT, and median onset of CRS and NT were 5 and 11 days, respectively, suggesting outpatient delivery of JCAR017 may be feasible. In the DLBCL cohort, 68 pts were evaluable for efficacy; best overall response, 3-month, and 6-month response rates in the FULL dataset were 75% (51/68), 49% (27/55), and 40% (14/35), respectively; and, in the CORE dataset, were 84% (41/49), 65% (26/40), and 57% (13/23). The best overall, 3-month, and 6-month CR rates were 61% (30/49), 53% (21/40), and 52% (12/23), respectively, in the CORE dataset. Among 16 double/triple hit pts, best ORR was 81%, and 3-month CR rate was 60%. A trend toward improved response rate at 3 months was observed in pts treated at DL2 compared to DL1. Conclusions: At the symposium, we will report updated efficacy and the preliminary safety profile for JCAR017, which supports potential outpatient administration in R/R Aggressive B-NHL patients. Clinical trial information: NCT02631044.

Hodgkin Lymphoma Version 1.2017, NCCN Clinical Practice Guidelines in Oncology

This portion of the NCCN Guidelines for Hodgkin lymphoma (HL) focuses on the management of classical HL. Current management of classical HL involves initial treatment with chemotherapy or combined modality therapy followed by restaging with PET/CT to assess treatment response using the Deauville criteria (5-point scale). The introduction of less toxic and more effective regimens has significantly advanced HL cure rates. However, long-term follow-up after completion of treatment is essential to determine potential long-term effects.

Immunotherapy of non-Hodgkin's lymphoma with a defined ratio of CD8+ and CD4+ CD19-specific chimeric antigen receptor-modified T cells

CD19-specific chimeric antigen receptor (CAR)-modified T cells have antitumor activity in B cell malignancies, but factors that affect toxicity and efficacy have been difficult to define because of differences in lymphodepletion and heterogeneity of CAR-T cells administered to individual patients. We conducted a clinical trial in which CD19 CAR-T cells were manufactured from defined T cell subsets and administered in a 1:1 CD4(+)/CD8(+) ratio of CAR-T cells to 32 adults with relapsed and/or refractory B cell non-Hodgkin's lymphoma after cyclophosphamide (Cy)-based lymphodepletion chemotherapy with or without fludarabine (Flu). Patients who received Cy/Flu lymphodepletion had increased CAR-T cell expansion and persistence, and higher response rates [50% complete remission (CR), 72% overall response rate (ORR)] than patients who received Cy-based lymphodepletion without Flu (8% CR, 50% ORR). The CR rate in patients treated with Cy/Flu at the maximally tolerated dose was 64% (82% ORR; n = 11). Cy/Flu minimized the effects of an immune response to the murine single-chain variable fragment component of the CAR, which limited CAR-T cell expansion and clinical efficacy in patients who received Cy-based lymphodepletion without Flu. Severe cytokine release syndrome (sCRS) and grade ≥3 neurotoxicity were observed in 13 and 28% of all patients, respectively. Serum biomarkers, one day after CAR-T cell infusion, correlated with subsequent sCRS and neurotoxicity. Immunotherapy with CD19 CAR-T cells in a defined CD4(+)/CD8(+) ratio allowed identification of correlative factors for CAR-T cell expansion, persistence, and toxicity, and facilitated optimization of lymphodepletion that improved disease response and overall and progression-free survival.