Prognostic relevance of circulating lymphoma cells at diagnosis in newly diagnosed follicular lymphoma patients.

Follicular lymphoma (FL) is the most common indolent B-cell non-Hodgkin lymphoma. Circulating lymphoma (CL) cells can be seen at diagnosis in some FL patients, however, previous studies evaluating this have shown mixed results. Therefore, we sought to evaluate the impact of CL at diagnosis on outcomes in patients with newly diagnosed FL using data from a single center. Patients were divided into CL+ and CL- based on immunophenotyping via peripheral blood (PB) flow cytometry. CL was defined as detectable clonally restricted B-cells that matched the actual or expected B-cell immunophenotype of FL. The primary endpoint was progression-free survival (PFS) after first-line treatment and secondary endpoints included overall response rate (ORR), overall survival (OS), diagnosis to treatment interval (DTI), progression of disease within 2 years of diagnosis (POD24), and cumulative incidence of transformation between the two groups. Among the 541 patients with FL, 204 had PB flow cytometry performed at diagnosis, and after excluding patients not meeting the eligibility criteria, 147 cases remained with 24 (16%) CL+ at diagnosis. Patients in the CL+ group were younger (53 vs. 58 years, p = 0.02), had more extranodal involvement (83% vs. 44%, p < 0.01), follicular lymphoma international prognostic index 3-5 (55% vs. 31%, p = 0.01), and a higher proportion received first-line immunochemotherapy (75% vs. 43%, p = 0.01) compared to the CL-group. The median PFS was not significantly different between CL+ (6.27 years, 95% CI = 3.61-NR) and CL- (6.61 years, 95% CI = 5.10-9.82) cohorts regardless of the first-line treatment or level of absolute PB CL cells. There was no significant difference in ORR, median OS, DTI, POD24, and cumulative incidence of transformation between the two groups. In our study, we found that the presence of CL cells at diagnosis in FL in the contemporary era did not impact outcomes and survival.

SOHO State of the Art Updates and Next Questions Updates on Building Your CAR-T Cell Program.

Chimeric antigen receptor T-cell (CAR-T) therapy has significantly impacted treatment algorithms and clinical outcomes for a variety of patients with hematologic malignancies over the past decade. The field of cellular immunotherapy is currently experiencing a rapid expansion of the number of patients eligible for CAR-T therapies as approvals are being seen in earlier lines of therapy. With the expanded patients eligible for these therapies, more treatment centers will be necessary to keep up with demand. Building a cellular therapy program can be a daunting task, and therefore, we present our experience with building a clinical cellular therapy program.

Post-infusion PD-1+CD8+CAR-T cells identify patients responsive to CD19-CAR-T therapy in non-Hodgkin's lymphoma.

Chimeric antigen receptor T cell therapy (CAR-T) has revolutionized treatment for relapsed/refractory (r/r) B-cell non-Hodgkin's lymphoma (NHL). Robust biomarkers and a complete understanding of CAR-T cell function in the post-infusion phase remain limited. Here we used a 37-color spectral flow cytometry panel to perform high dimensional single cell analysis of post-infusion samples in 26 patients treated with CD28 co-stimulatory domain containing commercial CAR-T (CD28-CAR-T) for NHL and focused on computationally gated CD8+ CAR-T cells. We found that the presence of post-infusion PD-1+ CD8+ CAR-T cells at the Day 14 timepoint highly correlated with the ability to achieve complete response (CR) by 6 months. Further analysis identified multiple subtypes of CD8+ PD-1+ CAR-T cells including PD-1+ TCF1+ stem-like CAR-T cells and PD-1+ TIM3+ effector-like CAR-T cells that correlated with improved clinical outcomes such as response and progression free survival. Additionally, we identified a subset of PD-1+ CD8+ CAR+ T cells with effector-like function that was increased in patients who achieved a CR and was associated with Grade 3 or higher immune effector cell-associated neurotoxicity syndrome. Here we identified robust biomarkers of response to CD28-CAR-T and highlight the importance of PD-1 positivity in CD8+ CAR-T cells post-infusion in achieving CR.

Real-world evidence of the safety and survival with CD19 CAR-T cell therapy for relapsed/refractory solid organ transplant-related PTLD.

The use of CD19 chimeric antigen receptor T-cell (CAR-T) therapy for relapsed/refractory solid organ transplantation (SOT)-related post-transplant lymphoproliferative disorder (PTLD) is not well studied. We conducted a multicentre, retrospective analysis of adults with relapsed/refractory SOT-associated PTLD. Among 22 relapsed/refractory SOT-PTLD patients, the pathology was monomorphic B cell. Prior SOTs included 14 kidney (64%), three liver (14%), two heart (9%), one intestinal (5%), one lung (5%), and one pancreas after kidney transplant (5%). The median time from SOT to PTLD diagnosis was 107 months. Pre-CAR-T bridging therapy was used in 55% of patients, and immunosuppression was stopped completely before CAR-T infusion in 64%. Eighteen (82%) patients experienced cytokine release syndrome: one (5%) each grade (G) 3 and G4. The immune effector cell-associated neurotoxicity syndrome was observed in 16 (73%) patients: six (27%) G3 and two (9%) G4. The overall response rate was 64% (55% complete response). Three patients (14%) experienced allograft rejection after CAR-T. The two-year progression-free survival and overall survival rates were 35% and 58%, respectively. Additionally, the achievement of CR post-CAR-T was strongly associated with survival. Collectively, the safety and efficacy of CD19 CAR-T therapy in relapsed/refractory SOT-related PTLD appeared similar to pivotal CAR-T data, including approximately one-third of patients achieving sustained remission.

Efficacy of checkpoint inhibition after CAR-T failure in aggressive B-cell lymphomas: outcomes from 15 US institutions.

Checkpoint inhibitor (CPI) therapy with anti-PD-1 antibodies has been associated with mixed outcomes in small cohorts of patients with relapsed aggressive B-cell lymphomas after CAR-T failure. To define CPI therapy efficacy more definitively in this population, we retrospectively evaluated clinical outcomes in a large cohort of 96 patients with aggressive B-cell lymphomas receiving CPI therapy after CAR-T failure across 15 US academic centers. Most patients (53%) had diffuse large B-cell lymphoma, were treated with axicabtagene ciloleucel (53%), relapsed early (≤180 days) after CAR-T (83%), and received pembrolizumab (49%) or nivolumab (43%). CPI therapy was associated with an overall response rate of 19% and a complete response rate of 10%. Median duration of response was 221 days. Median progression-free survival (PFS) and overall survival (OS) were 54 and 159 days, respectively. Outcomes to CPI therapy were significantly improved in patients with primary mediastinal B-cell lymphoma. PFS (128 vs 51 days) and OS (387 vs 131 days) were significantly longer in patients with late (>180 days) vs early (≤180 days) relapse after CAR-T. Grade ≥3 adverse events occurred in 19% of patients treated with CPI. Most patients (83%) died, commonly because of progressive disease. Only 5% had durable responses to CPI therapy. In the largest cohort of patients with aggressive B-cell lymphoma treated with CPI therapy after CAR-T relapse, our results reveal poor outcomes, particularly among those relapsing early after CAR-T. In conclusion, CPI therapy is not an effective salvage strategy for most patients after CAR-T, where alternative approaches are needed to improve post-CAR-T outcomes.

Identifying aggressive subsets within diffuse large B-cell lymphoma: implications for treatment approach.

INTRODUCTION: While the majority of patients diagnosed with diffuse large B-cell lymphoma (DLBCL) can be cured with front-line chemoimmunotherapy, a subset of patients with high-risk disease remain challenging to treat. Identification of high-risk DLBCL is important as future therapy options are explored. AREAS COVERED: We discuss the clinical, pathologic, and molecular risk stratification in DLBCL and how these factors are incorporated into the decision making for the front-line therapy. EXPERT OPINION: Clinical and pathological risk stratification has long been the standard for identifying likelihood of future disease progression and overall survival; however, these prediction models lack the granularity of individual patient pathology and response to therapy. Molecular subtypes defined through whole exome sequencing have independent prognostic significance. While identifying molecular drivers of aggressive disease has provided the opportunity to analyze novel therapy combinations with front-line chemoimmunotherapy, only modest benefit has been observed when targeting DLBCL subtypes. Combining clinical, pathologic, and molecular data will likely result in significant improvement in our ability to identify the most aggressive DLBCL subsets. Novel therapies and trial designs will continue to play an important role as we target these at-risk populations in the future.

An international analysis evaluating frontline bendamustine with rituximab in extranodal marginal zone lymphoma.

Extranodal marginal zone lymphoma (EMZL) is a heterogeneous non-Hodgkin lymphoma. No consensus exists regarding the standard-of-care in patients with advanced-stage disease. Current recommendations are largely adapted from follicular lymphoma, for which bendamustine with rituximab (BR) is an established approach. We analyzed the safety and efficacy of frontline BR in EMZL using a large international consortium. We included 237 patients with a median age of 63 years (range, 21-85). Most patients presented with Eastern Cooperative Oncology Group (ECOG) performance status 0 to 1 (n = 228; 96.2%), stage III/IV (n = 179; 75.5%), and intermediate (49.8%) or high (33.3%) Mucosa Associated Lymphoid Tissue International Prognosis Index (MALT-IPI). Patients received a median of 6 (range, 1-8) cycles of BR, and 20.3% (n = 48) received rituximab maintenance. Thirteen percent experienced infectious complications during BR therapy; herpes zoster (4%) was the most common. Overall response rate was 93.2% with 81% complete responses. Estimated 5-year progression-free survival (PFS) and overall survival (OS) were 80.5% (95% CI, 73.1% to 86%) and 89.6% (95% CI, 83.1% to 93.6%), respectively. MALT-IPI failed to predict outcomes. In the multivariable model, the presence of B symptoms was associated with shorter PFS. Rituximab maintenance was associated with longer PFS (hazard ratio = 0.16; 95% CI, 0.04-0.71; P = .016) but did not impact OS. BR is a highly effective upfront regimen in EMZL, providing durable remissions and overcoming known adverse prognosis factors. This regimen is associated with occurrence of herpes zoster; thus, prophylactic treatment may be considered.

Cellular Therapy Advances in Chronic Lymphocytic Leukemia and Richter's Syndrome.

Over the past 10 years, there have been great treatment advances for chronic lymphocytic leukemia (CLL) with the development of small molecule inhibitors. However, there remains an area of unmet need for patients who progress on novel therapies. The development of cellular therapies in CLL has been hindered by CLL induced immunosuppression. Fortunately, recent progress in various methods in immunomodulation may help overcome this limitation in CLL. These advances have spurred ongoing interest in the development of cellular therapies for CLL, including chimeric antigen receptor (CAR) T cell therapies, bi-specific antibodies, and use of natural killer cells. These novel treatment modalities may hold promise for patients with refractory, and potentially transformed disease. Here, we discuss the development of CAR-T cell therapy in CLL and the impact of combining CAR-T and small molecule inhibitors on treatment outcomes, the evolving role of bi-specific antibodies and natural killer cells, and comment on the use of cellular therapies for Richter's syndrome.

Pretherapy metabolic tumor volume is associated with response to CD30 CAR T cells in Hodgkin lymphoma.

Our group has recently demonstrated that chimeric antigen receptor T-cell therapy targeting the CD30 antigen (CD30.CAR-T) is highly effective in patients with relapsed and refractory (r/r) classical Hodgkin lymphoma (cHL). Despite high rates of clinical response, relapses and progression were observed in a subset of patients. The objective of this study was to characterize clinical and correlative factors associated with progression-free survival (PFS) after CD30.CAR-T cell therapy. We evaluated correlatives in 27 patients with r/r cHL treated with lymphodepletion and CD30.CAR-T cells. With a median follow-up of 9.5 months, 17 patients (63%) progressed, with a median PFS of 352 days (95% confidence interval: 116-not reached), and 2 patients died (7%) with a median overall survival of not reached. High metabolic tumor volume (MTV, >60 mL) immediately before lymphodepletion and CD30.CAR-T cell infusion was associated with inferior PFS (log rank, P = .02), which persisted after adjusting for lymphodepletion and CAR-T dose (log rank, P = .01 and P = .006, respectively). In contrast, receiving bridging therapy, response to bridging therapy, CD30.CAR-T expansion/persistence, and percentage of CD3+PD-1+ lymphocytes over the first 6 weeks of therapy were not associated with differences in PFS. In summary, this study reports an association between high baseline MTV immediately before lymphodepletion and CD30.CAR-T cell infusion and worse PFS in patients with r/r cHL. This trial was registered at www.clinicaltrials.gov as #NCT02690545.

Single-route CNS prophylaxis for aggressive non-Hodgkin lymphomas: real-world outcomes from 21 US academic institutions.

Prophylaxis is commonly used to prevent central nervous sy stem (CNS) relapse in diffuse large B-cell lymphoma (DLBCL), with no clear standard of care. We retrospectively evaluated 1162 adult patients across 21 US academic centers with DLBCL or similar histologies who received single-route CNS prophylaxis as part of frontline therapy between 2013 and 2019. Prophylaxis was administered intrathecally(IT) in 894 (77%) and using systemic high-dose methotrexate (HD-MTX) in 236 (20%); 32 patients (3%) switched route due to toxicity and were assessed separately. By CNS-International Prognostic Index (IPI), 18% were considered low-risk, 51% moderate, and 30% high. Double-hit lymphoma (DHL) was confirmed in 243 of 866 evaluable patients (21%). Sixty-four patients (5.7%) had CNS relapse after median 7.1 months from diagnosis, including 15 of 64 (23%) within the first 6 months. There was no significant difference in CNS relapse between IT and HD-MTX recipients (5.4% vs 6.8%, P = .4), including after propensity score matching to account for differences between respective recipient groups. Weighting by CNS-IPI, expected vs observed CNS relapse rates were nearly identical (5.8% vs 5.7%). Testicular involvement was associated with high risk of CNS relapse (11.3%) despite most having lower CNS-IPI scores. DHL did not significantly predict for CNS relapse after single-route prophylaxis, including with adjustment for treatment regimen and other factors. This large study of CNS prophylaxis recipients with DLBCL found no significant difference in CNS relapse rates between routes of administration. Relapse rates among high-risk subgroups remain elevated, and reconsideration of prophylaxis strategies in DLBCL is of critical need.

Multicenter analysis of geriatric fitness and real-world outcomes in older patients with classical Hodgkin lymphoma.

We performed a multicenter retrospective analysis across 10 US academic medical centers to evaluate treatment patterns and outcomes in patients age ≥60 years with classic Hodgkin lymphoma (cHL) from 2010-2018. Among 244 eligible patients, median age was 68, 63% had advanced stage (III/IV), 96% had Eastern Cooperative Oncology Group performance status (PS) 0-2, and 12% had documented loss of ≥1 activity of daily living (ADL). Medical comorbidities were assessed by the Cumulative Illness Rating Scale-Geriatric (CIRS-G), where n = 44 (18%) had total scores ≥10. Using multivariable Cox models, only ADL loss predicted shorter progression-free (PFS; hazard ratio [HR] 2.13, P = .007) and overall survival (OS; HR 2.52, P = .02). Most patients (n = 203, 83%) received conventional chemotherapy regimens, including doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD; 56%), AVD (14%), and AVD with brentuximab vedotin (BV; 9%). Compared to alternative therapies, conventional regimens significantly improved PFS (HR 0.46, P = .0007) and OS (HR 0.31, P = .0003). Survival was similar following conventional chemotherapy in those ages 60-69 vs ≥70: PFS HR 0.88, P = .63; OS HR 0.73, P = .55. Early treatment discontinuation due to toxicity was more common with CIRS-G ≥10 (28% vs 12%, P = .016) or documented geriatric syndrome (28% vs 13%, P = .02). A competing risk analysis demonstrated improved disease-related survival with conventional therapy (HR 0.29, P = .02) and higher mortality from causes other than disease or treatment with high CIRS-G or geriatric syndromes. This study suggests conventional chemotherapy regimens remain a standard of care in fit older patients with cHL, and highlights the importance of geriatric assessments in defining fitness for cHL therapy going forward.

Identification of high-risk monomorphic post-transplant lymphoproliferative disorder following solid organ transplantation.

Monomorphic post-transplant lymphoproliferative disorder (M-PTLD) occurring after solid organ transplant histologically resembles aggressive non-Hodgkin lymphomas, with diffuse large B-cell lymphoma being the most common. In a cohort of 40 patients with DLBCL-type M-PTLD, inferior progression free survival (PFS) was observed for Revised International Prognostic Index (R-IPI) >2 (p = 0.01) and high-risk pathologic features (p = 0.02), defined by double expressor lymphoma, MYC rearrangement, or increased copy number of either MYC or BCL2. Overall survival (OS) was inferior in R-IPI >2 (p = 0.002) and high-risk pathologic features (p = 0.003). Combining both R-IPI >2 and high-risk pathologic features resulted in well-delineated good, intermediate, and poor risk groups of DLBCL-type M-PTLD with respect to both PFS and OS (p < 0.001). Our results demonstrate a prognostic role for both the R-IPI score and presence of high-risk pathologic features in DLBCL-type M-PTLD.

Therapeutic Updates for Relapsed and Refractory Classical Hodgkin Lymphoma.

Hodgkin lymphoma (HL) is a B-cell malignancy representing approximately one in ten lymphomas diagnosed in the United States annually. The majority of patients with HL can be cured with chemotherapy; however, 5-10% will have refractory disease to front-line therapy and 10-30% will relapse. For those with relapsed or refractory (r/r) HL, salvage chemotherapy followed by autologous stem cell transplant (ASCT) is standard of care, but half of patients will subsequently have disease progression. Relapse following ASCT has been associated with exceedingly poor prognosis with a median survival of only 26 months. However, in recent years, novel agents including brentuximab vedotin (BV) and programmed cell death protein 1 monoclonal antibodies (anti-PD-1, nivolumab and pembrolizumab) have been shown to extend overall survival in r/r HL. With the success of novel agents in relapsed disease after ASCT, these therapies are beginning to show clinically meaningful response rates prior to ASCT. Finally, a new investigation in r/r HL continues to produce promising treatment options even after ASCT including CD30 directed chimeric antigen receptor T-cell therapy. In this review, we will discuss the recent advances of BV and anti-PD-1 therapy prior to ASCT, novel approaches in r/r HL after ASCT, and review active clinical trials.

Allogeneic stem cell transplantation for chronic lymphocytic leukemia in the era of novel agents.

Although novel agents (NAs) have improved outcomes for patients with chronic lymphocytic leukemia (CLL), a subset will progress through all available NAs. Understanding outcomes for potentially curative modalities including allogeneic hematopoietic stem cell transplantation (alloHCT) following NA therapy is critical while devising treatment sequences aimed at long-term disease control. In this multicenter, retrospective cohort study, we examined 65 patients with CLL who underwent alloHCT following exposure to ≥1 NA, including baseline disease and transplant characteristics, treatment preceding alloHCT, transplant outcomes, treatment following alloHCT, and survival outcomes. Univariable and multivariable analyses evaluated associations between pre-alloHCT factors and progression-free survival (PFS). Twenty-four-month PFS, overall survival (OS), nonrelapse mortality, and relapse incidence were 63%, 81%, 13%, and 27% among patients transplanted for CLL. Day +100 cumulative incidence of grade III-IV acute graft-vs-host disease (GVHD) was 24%; moderate-severe GVHD developed in 27%. Poor-risk disease characteristics, prior NA exposure, complete vs partial remission, and transplant characteristics were not independently associated with PFS. Hematopoietic cell transplantation-specific comorbidity index independently predicts PFS. PFS and OS were not impacted by having received NAs vs both NAs and chemoimmunotherapy, 1 vs ≥2 NAs, or ibrutinib vs venetoclax as the line of therapy immediately pre-alloHCT. AlloHCT remains a viable long-term disease control strategy that overcomes adverse CLL characteristics. Prior NAs do not appear to impact the safety of alloHCT, and survival outcomes are similar regardless of number of NAs received, prior chemoimmunotherapy exposure, or NA immediately preceding alloHCT. Decisions about proceeding to alloHCT should consider comorbidities and anticipated response to remaining therapeutic options.

Assessment of the Efficacy of Therapies Following Venetoclax Discontinuation in CLL Reveals BTK Inhibition as an Effective Strategy.

PURPOSE: Venetoclax-based therapy is a standard-of-care option in first-line and relapsed/refractory chronic lymphocytic leukemia (CLL). Patient management following venetoclax discontinuation remains nonstandard and poorly understood. EXPERIMENTAL DESIGN: To address this, we conducted a large international study to identify a cohort of 326 patients who discontinued venetoclax and have been subsequently treated. Coprimary endpoints were overall response rate (ORR) and progression-free survival for the post-venetoclax treatments stratified by treatment type [Bruton's tyrosine kinase inhibitor (BTKi), PI3K inhibitor (PI3Ki), and cellular therapies]. RESULTS: We identified patients with CLL who discontinued venetoclax in the first-line (4%) and relapsed/refractory settings (96%). Patients received a median of three therapies prior to venetoclax; 40% were BTKi naïve (n = 130), and 81% were idelalisib naïve (n = 263). ORR to BTKi was 84% (n = 44) in BTKi-naïve patients versus 54% (n = 30) in BTKi-exposed patients. We demonstrate therapy selection following venetoclax requires prior novel agent exposure consideration and discontinuation reasons. CONCLUSIONS: For BTKi-naïve patients, selection of covalently binding BTKis results in high ORR and durable remissions. For BTKi-exposed patients, covalent BTK inhibition is not effective in the setting of BTKi resistance. PI3Kis following venetoclax do not appear to result in durable remissions. We conclude that BTKi in naïve or previously responsive patients and cellular therapies following venetoclax may be the most effective strategies.See related commentary by Rogers, p. 3501.