Conventional and novel [18F]FDG PET/CT features as predictors of CAR-T cell therapy outcome in large B-cell lymphoma.

Relapse and toxicity limit the effectiveness of chimeric antigen receptor T-cell (CAR-T) therapy for large B-cell lymphoma (LBCL), yet biomarkers that predict outcomes and toxicity are lacking. We examined radiomic features extracted from pre-CAR-T 18F-fluorodeoxyglucose positron emission tomography/computed tomography ([18F]FDG PET/CT) scans (n = 341) of 180 patients (121 male; median age, 66 years). Three conventional (maximum standardized uptake value [SUVmax], metabolic tumor volume [MTV], total lesion glycolysis [TLG]) and 116 novel radiomic features were assessed, along with inflammatory markers, toxicities, and outcomes. At both pre-apheresis and pre-infusion time points, conventional PET features of disease correlated with elevated inflammatory markers. At pre-infusion, MTV was associated with grade ≥ 2 cytokine release syndrome (odds ratio [OR] for 100 mL increase: 1.08 [95% confidence interval (CI), 1.01-1.20], P = 0.031), and SUVmax was associated with failure to achieve complete response (CR) (OR 1.72 [95% CI, 1.24-2.43], P < 0.001). Higher pre-apheresis and pre-infusion MTV values were associated with shorter progression-free survival (PFS) (HR for 10-unit increase: 1.11 [95% CI, 1.05-1.17], P < 0.001; 1.04 [95% CI, 1.02-1.07], P < 0.001) and shorter overall survival (HR for 100-unit increase: 1.14 [95% CI, 1.07-1.21], P < 0.001; 1.04 [95% CI, 1.02-1.06], P < 0.001). A combined MTV and LDH measure stratified patients into high and low PFS risk groups. Multiple pre-infusion novel radiomic features were associated with CR. These quantitative conventional [18F]FDG PET/CT features obtained before CAR-T cell infusion, which were correlated with inflammation markers, may provide prognostic biomarkers for CAR-T therapy efficacy and toxicity. The use of conventional and novel radiomic features may thus help identify high-risk patients for earlier interventions.

Identifying an optimal fludarabine exposure for improved outcomes after axi-cel therapy for aggressive B-cell non-Hodgkin lymphoma.

Fludarabine is one of the most common agents given for lymphodepletion before CD19 chimeric antigen receptor T cells, but its optimal therapeutic intensity is unknown. Using data from a multicenter consortium, we estimated fludarabine exposure (area under the curve [AUC]) using a population pharmacokinetic (PK) model in 199 adult patients with aggressive B-cell non-Hodgkin lymphomas who received commercial axicabtagene ciloleucel (Axi-cel). We evaluated the association of estimated fludarabine AUC with key outcomes, aiming to find an AUC that optimized efficacy and tolerability. We identified low (<18 mg × hour/L [mgh/L]), optimal (18-20 mgh/L), and high (>20 mgh/L) AUC groups for analyses; the 6-month cumulative incidences of relapse/progression of disease (relapse/POD) by AUC groups were 54% (45%-62%), 28% (15%-44%), and 30% (14%-47%), respectively; and the 1-year progression-free survival (PFS) rates were 39% (31%-48%), 66% (52%-84%), and 46% (30%-70%) and the overall survival (OS) rates were 58% (50%-67%), 77% (64%-92%), and 66% (50%-87%), respectively. In multivariable analyses compared with low AUC, an optimal AUC was associated with the highest PFS (hazard ratio [HR], 0.52; 0.3-0.91; P = .02) and lowest risk of relapse/POD (HR, 0.46; 0.25-0.84; P = .01) without an increased risk of any-grade cytokine release syndrome (HR, 1.1; 0.7-1.6; P = .8) or and immune effector cell-associated neurotoxicity syndrome (ICANS) (HR, 1.36; 0.83-2.3; P = .2). A high AUC was associated with the greatest risk of any-grade ICANS (HR, 1.9; 1.1-3.2; P = .02). Although the main cause of death in all groups was relapse/POD, nonrelapse-related deaths, including 3 deaths from ICANS, were more frequent in the high AUC group. These findings suggest that PK-directed fludarabine dosing to achieve an optimal AUC may result in improved outcomes for patients receiving axi-cel.

CD19 CAR T-cell therapy and prophylactic anakinra in relapsed or refractory lymphoma: phase 2 trial interim results.

In preclinical models, anakinra, an IL-1 receptor antagonist (IL-1Ra), reduced immune effector cell-associated neurotoxicity syndrome (ICANS) without compromising anti-CD19 chimeric antigen receptor (CAR) T-cell efficacy. We initiated a phase 2 clinical trial of anakinra in patients with relapsed/refractory large B-cell lymphoma and mantle cell lymphoma treated with commercial anti-CD19 CAR T-cell therapy. Here we report a non-prespecified interim analysis reporting the final results from cohort 1 in which patients received subcutaneous anakinra from day 2 until at least day 10 post-CAR T-cell infusion. The primary endpoint was the rate of severe (grade ≥3) ICANS. Key secondary endpoints included the rates of all-grade cytokine release syndrome (CRS) and ICANS and overall disease response. Among 31 treated patients, 74% received axicabtagene ciloleucel, 13% received brexucabtagene ciloleucel and 4% received tisagenlecleucel. All-grade ICANS occurred in 19%, and severe ICANS occurred in 9.7% of patients. There were no grade 4 or 5 ICANS events. All-grade CRS occurred in 74%, and severe CRS occurred in 6.4% of patients. The overall disease response rate was 77% with 65% complete response rate. These initial results show that prophylactic anakinra resulted in a low incidence of ICANS in patients with lymphoma receiving anti-CD19 CAR T-cell therapy and support further study of anakinra in immune-related neurotoxicity syndromes.

Bridging Radiation Rapidly and Effectively Cytoreduces High-Risk Relapsed/Refractory Aggressive B Cell Lymphomas Prior to Chimeric Antigen Receptor T Cell Therapy.

Greater tumor burden before CD19-targeted chimeric antigen receptor T cell (CAR-T) therapy predicts lower complete response rate and shorter overall survival (OS) in patients with aggressive non-Hodgkin lymphoma (NHL). Recent patterns of failure studies have identified lesion characteristics, including size, standard uptake value (SUV), and extranodal location, as associated with post-CAR-T therapy failure. Here we analyzed the effect of bridging radiation-containing treatment (BRT) on pre-CAR-T therapy lesion- and patient-level characteristics and post-CAR-T therapy outcomes, including patterns of failure. Consecutive NHL patients who received radiation therapy from 30 days before leukapheresis until CAR T cell infusion were reviewed. Metabolic tumor volume (MTV) was contoured with a threshold SUV of 4. The first post-CAR-T therapy failures were categorized as preexisting/new/mixed with respect to pre-CAR-T therapy disease and in-field/marginal/distant with respect to BRT. Forty-one patients with diffuse large B cell lymphoma (DLBCL; n = 33), mantle cell lymphoma (n = 7), or Burkitt lymphoma (n = 1) were identified. BRT significantly improved established high-risk parameters of post-CAR-T therapy progression, including in-field median MTV (45.5 cc to .2 cc; P < .001), maximum SUV (18.1 to 4.4; P < .001), diameter (5.5 cm to 3.2 cm; P < .001), and lactate dehydrogenase (LDH; 312 to 232; P = .025). DLBCL patients with lower LDH levels post-BRT had improved progression-free survival (PFS; P = .001). In DLBCL, first failures were new in 7 of 19 patients, preexisting in 5 of 19, and mixed in 7 of 19; with respect to BRT, 4 of 19 were in-field and 4 of 19 were marginal. Post-CAR-T therapy survival was similar in patients with initially low MTV and those with newly low MTV post-BRT using a statistically determined threshold of 16 cc (PFS, 26 months versus 31 months; OS unreached for both). BRT produced significant cytoreductions in diameter, SUV, MTV, and LDH, all predictors of poor post-CAR-T therapy outcomes. Similar PFS and OS in patients with initially low MTV and those who achieved newly low MTV after BRT suggest that BRT may "convert" poor-risk patients to better risk. In the future, the response to BRT may allow for risk stratification and individualization of bridging strategies.

EASIX score predicts inferior survival after allogeneic hematopoietic cell transplantation.

The Endothelial Activation and Stress Index (EASIX) is a prognostic tool that uses common clinical laboratory values and has been shown to predict non-relapse mortality (NRM) and overall survival (OS) at the onset of acute graft-versus-host disease (GVHD) after allogeneic hematopoietic cell transplantation (HCT). We hypothesized that EASIX calculated at different time points pre- and post- HCT may predict NRM and OS, and that EASIX calculated at onset of GVHD may predict response to steroids. We evaluated the EASIX score pre- and post-HCT in 152 patients with lymphoid malignancies undergoing unmodified reduced intensity conditioning (RIC) alloHCT with uniform GVHD prophylaxis. In multivariate analysis, EASIX calculated pre-HCT was significantly associated with higher NRM (HR = 1.64, p = 0.009) and lower OS (HR = 1.33, p = 0.046). Furthermore, EASIX calculated at day 30 and at day 100 was associated with increased NRM (HR = 1.65, p < 0.001; and HR = 1.65, p < 0.001) and decreased OS (HR = 1.27, p = 0.018; and HR = 1.49, p < 0.001), independent of HCT-CI, disease and conditioning regimen. Our study shows that high EASIX scores at various time points pre- and post-HCT are significantly associated with poorer overall outcomes. EASIX provides an independent and easily accessible tool to predict outcomes that can be complementary to other measures of risk stratification for patients undergoing HCT.

Allogeneic transplant following CAR T-cell therapy for large B-cell lymphoma.

Allogeneic hematopoietic cell transplantation (alloHCT) can potentially salvage large B-cell lymphoma (LBCL) patients experiencing treatment failure after chimeric antigen receptor T-cell therapy (CAR T). Nonetheless, data on the efficacy and toxicities of alloHCT after receipt of CAR T are limited. We report a multicenter retrospective study assessing the safety, toxicities, and outcomes of alloHCT in LBCL patients following CAR T failure. Eighty-eight patients with relapsed, refractory LBCL received an alloHCT following anti-CD19 CAR T failure. The median number of lines of therapy between CAR T infusion and alloHCT was one (range, 0-7). Low intensity conditioning was used in 77% (n=68) and peripheral blood was the most common graft source (86%, n=76). The most common donor types were matched unrelated donor (39%), followed by haploidentical (30%) and matched related donor (26%). Median follow-up of survivors was 15 months (range, 1-72). One-year overall survival, progression-free survival, and graft-versus-host disease-free relapse-free survival were 59%, 45%, and 39% respectively. One-year non-relapse mortality and progression/relapse were 22% and 33% respectively. On multivariate analysis, <2 lines of intervening therapy between CAR T and alloHCT and complete response at time of alloHCT were associated with better outcomes. In conclusion, alloHCT after CAR T failure can provide durable remissions in a subset of patients.

Chimeric antigen receptor T-cell therapy yields similar outcomes in patients with and without cytokine release syndrome.

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized the treatment of many patients with aggressive relapsed or refractory large B-cell lymphoma (LBCL). Treatment can be complicated by clinically evident cytokine release syndrome (CRS), which is characterized by the development of fever, hypoxia, and hypotension, and can be life-threatening. Most patients treated with CAR-T cells develop CRS, which is thought to represent an immune phenomenon. It was previously unknown whether patients who did not develop CRS had reduced CAR-T cell activity and were therefore likely to have worse outcomes. We conducted a multicenter retrospective analysis of 352 adult patients treated at 8 academic medical centers in the United States who received axicabtagene ciloleucel or tisagenlecleucel for the treatment of LBCL. The outcomes of interest included progression-free survival, overall survival, complete response rate, and overall response rate. Of the included patients, 262 (74.4%) developed CRS. There was no significant difference in progression-free survival (P = .99) or overall survival (P = .16) between patients who developed CRS and those who did not develop CRS. Peak ferritin levels >5000 ng/mL during treatment and lactate dehydrogenase levels greater than the institutional upper limit of normal before lymphodepleting chemotherapy were associated with significantly worse progression-free and overall survival in the multivariate analysis. There was no significant difference in the complete response or overall response rates between patients who did and did not develop CRS. In this retrospective analysis, we report that patients who develop CRS have clinical outcomes similar to those of patients without CRS treated with commercial anti-CD19 CAR-T cells.

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.

Low toxicity and excellent outcomes in patients with DLBCL without residual lymphoma at the time of CD19 CAR T-cell therapy.

CD19 chimeric antigen receptor (CAR) T-cell therapy represents a breakthrough for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL), inducing sustained remissions in these patients. However, CAR T cells can result in significant toxicities. Preinfusion disease burden is associated with toxicities and outcomes after CAR T-cell therapy. We identified 33 patients with R/R DLBCL treated at 8 academic centers who had no detectable disease at the time of CAR T-cell therapy. The median time from leukapheresis to CAR T-cell infusion was 48 (19-193) days. Nine patients received axicabtagene ciloleucel, and 24 received tisagenlecleucel. There was no severe (grade ≥3) cytokine release syndrome, and only 1 patient developed severe neurotoxicity (grade 4). After a median follow-up of 16 months, 13 patients relapsed (39.4%) and 6 died (18.1%). One-year event-free survival and overall survival were 59.6% and 81.3%, respectively. Our findings suggest that, in patients with R/R DLBCL who have an indication for CAR T-cell therapy, treating patients in complete remission at the time of infusion is feasible, safe, and associated with favorable disease control. Further exploration in a larger clinical trial setting is warranted.

Vitamin D Insufficiency and Clinical Outcomes with Chimeric Antigen Receptor T-Cell Therapy in Large B-cell Lymphoma.

Vitamin D insufficiency is a potentially modifiable risk factor for poor outcomes in newly diagnosed large B-cell lymphoma (LBCL). However, the role of circulating vitamin D concentrations in relapsed/refractory LBCL treated with CD19-directed chimeric antigen receptor T-cell therapy (CAR-T) is currently unknown. This was a single-center, observational study that evaluated the association of pre-CAR-T 25-hydroxyvitamin D (25-OHD) status with 100-day complete response, progression-free survival, overall survival, and CAR-T-related toxicity in 111 adult relapsed/refractory LBCL patients. Vitamin D insufficiency was defined as ≤30 ng/mL in accordance with the Endocrine Society guidelines. The median pre-CAR-T 25-hydroxyvitamin D concentration was 24 ng/mL (interquarile range = 18-34). Vitamin D-insufficient patients (≤30 ng/mL; n = 73 [66%]) were significantly younger than their vitamin D-replete (>30 ng/mL; n = 38 [34%]) counterparts (P= .039). The vitamin D-insufficient cohort was enriched for de novo LBCL as the histological subtype (P= .026) and had a higher proportion of tisagenlecleucel as the CAR-T product (P= .049). There were no other significant differences in the baseline characteristics between the two groups. In vitamin D-insufficient compared to -replete patients, 100-day complete response was 55% versus 76% (P= .029), and 2-year overall survival was 41% versus 71% (P= .061), respectively. In multivariate analysis, vitamin D insufficiency remained significantly associated with 100-day complete response (odds ratio 2.58 [1.05-6.83]; P= .045) and overall survival (hazard ratio 2.24 [1.08-4.66], P= .030). In recipients of tisagenlecleucel, vitamin D insufficiency was associated with significantly lower cell viability of the infused CAR-T product (P= .015). Finally, pretreatment vitamin D insufficiency did not predict for subsequent CAR-T-related toxicity. This is the first report to demonstrate that vitamin D insufficiency is associated with inferior clinical outcomes in CAR-T recipients. Further study into the mechanistic insights of this finding, and the potential role of vitamin D supplementation to optimize CAR-T are warranted.

The Simplified Comorbidity Index: a new tool for prediction of nonrelapse mortality in allo-HCT.

Individual comorbidities have distinct contributions to nonrelapse mortality (NRM) following allogeneic hematopoietic cell transplantation (allo-HCT). We studied the impact of comorbidities individually and in combination in a single-center cohort of 573 adult patients who underwent CD34-selected allo-HCT following myeloablative conditioning. Pulmonary disease, moderate to severe hepatic comorbidity, cardiac disease of any type, and renal dysfunction were associated with increased NRM in multivariable Cox regression models. A Simplified Comorbidity Index (SCI) composed of the 4 comorbidities predictive of NRM, as well as age >60 years, stratified patients into 5 groups with a stepwise increase in NRM. NRM rates ranged from 11.4% to 49.9% by stratum, with adjusted hazard ratios of 1.84, 2.59, 3.57, and 5.38. The SCI was also applicable in an external cohort of 230 patients who underwent allo-HCT with unmanipulated grafts following intermediate-intensity conditioning. The area under the receiver operating characteristic curve (AUC) of the SCI for 1-year NRM was 70.3 and 72.0 over the development and external-validation cohorts, respectively; corresponding AUCs of the Hematopoietic Cell Transplantation-specific Comorbidity Index (HCT-CI) were 61.7 and 65.7. In summary, a small set of comorbidities, aggregated into the SCI, is highly predictive of NRM. The new index stratifies patients into distinct risk groups, was validated in an external cohort, and provides higher discrimination than does the HCT-CI.

The geriatric syndrome of sarcopenia impacts allogeneic hematopoietic cell transplantation outcomes in older lymphoma patients.

Older patients with advanced hematologic malignancies are increasingly considered for allogeneic hematopoietic cell transplantation (allo-HCT) yet their survival outcomes remain suboptimal. We and others have previously shown that pre-HCT multi-morbidity and functional limitation and post-HCT geriatric syndromes significantly impact outcomes. Sarcopenia, an accelerated loss of muscle mass and function, has been increasingly recognized in older cancer patients. We identified 146 lymphoma patients 50 years or older who were allografted from 2008 to 2018 at our institution and found that before allo-HCT, 80 (55%) patients were sarcopenic. Pre-HCT sarcopenia was significantly associated with overall survival, progression-free survival, and nonrelapse mortality independent of multi-morbidity and functional limitation. In 6-month landmark analysis, post-HCT sarcopenia remained significantly associated with survival. Our findings illustrate the high prevalence and profound impact of sarcopenia on survival. While requiring prospective confirmation, preemptive, longitudinal, and multidisciplinary interventions for sarcopenia are warranted to improve HCT outcomes for older patients.