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.

Comorbidities Predict Inferior Survival in Patients Receiving Chimeric Antigen Receptor T Cell Therapy for Diffuse Large B Cell Lymphoma: A Multicenter Analysis

Chimeric antigen receptor T cell (CAR-T) therapy is approved for treatment of relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL). Here we evaluate whether comorbidities, calculated using the Cumulative Illness Rating Scale (CIRS), predict survival for these patients. A retrospective chart review was performed at 4 academic institutions. All patients who underwent leukapheresis for commercial CAR-T therapy for R/R DLBCL were included. CIRS scores were calculated at the time of leukapheresis. High comorbidity was defined as either CIRS ≥7 or the presence of severe impairment (CIRS 3/4 in ≥1 system; CIRS-3+). Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method, and differences in curves were detected by the log-rank test. A total of 130 patients were analyzed, 56.9% with CIRS ≥7 and 56.2% with CIRS-3+. After a median follow-up of 13 months, the median PFS was 6.7 months, and the median OS was not reached. On univariable analysis, Eastern Cooperative Oncology Group (ECOG) performance status (PS) was associated with inferior PFS (hazard ratio [HR], 1.45; 95% confidence interval [CI], 1.03-2.05; P = .03) and OS (HR, 1.76; 95% CI, 1.17-2.64; P = .007). Higher CIRS (CIRS ≥7 or CIRS-3+) was associated with inferior OS (HR, 2.12; 95%, CI, 1.06-4.22; P = .03) and a nonsignificant trend in worse PFS (HR, 1.45; 95% CI, .87-2.44; P = .16). In multivariable analyses, CIRS ≥7 or CIRS-3+ and ECOG PS maintained independent prognostic significance. Comorbidities as determined by CIRS and ECOG PS predict inferior survival in patients receiving CAR-T therapy for R/R DLBCL.

Cardiovascular Toxicities of BTK Inhibitors in Chronic Lymphocytic Leukemia: JACC: CardioOncology State-of-the-Art Review

Over the past decade, the treatment landscape of chronic lymphocytic leukemia (CLL) has dramatically changed, shifting from cytotoxic chemotherapy to targeted therapies. Bruton's tyrosine kinase (BTK) inhibitors have revolutionized the treatment of CLL and are increasingly applied in many other malignancies. However, ibrutinib, the first BTK inhibitor approved, is associated with serious toxicities, including atrial fibrillation in up to 38% of patients, ventricular arrhythmias, and other cardiovascular toxicities. Emerging data suggest several newer BTK inhibitors (eg, acalabrutinib, zanubrutinib) are still associated with cardiotoxic risks. This review examines the current state of evidence, including incidence rates, risk factors, mechanisms, and management strategies of cardiovascular toxicities with BTK inhibitors and other CLL therapies. We specifically focus on atrial fibrillation, ventricular arrhythmias/sudden death, hypertension, heart failure, bleeding, and stroke. We also touch on other emerging BTK therapies (eg, pirtobrutinib). Finally, we highlight key unanswered questions and future directions of research.

A validated composite comorbidity index predicts outcomes of CAR T-cell therapy in patients with diffuse large B-cell lymphoma

Chimeric antigen receptor T-cell therapy (CART) has extended survival of patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL). However, limited durability of response and prevalent toxicities remain problematic. Identifying patients who are at high risk of disease progression, toxicity, and death would inform treatment decisions. Although the cumulative illness rating scale (CIRS) has been shown to correlate with survival in B-cell malignancies, no prognostic score has been independently validated in CART recipients. We retrospectively identified 577 patients with relapsed/refractory DLBCL indicated for CART at 9 academic centers to form a learning cohort (LC). Random survival forest modeling of overall survival (OS) and progression-free survival (PFS) was performed to determine the most influential CIRS organ systems and severity grades. The presence of a severe comorbidity (CIRS score ≥ 3) in the respiratory, upper gastrointestinal, hepatic, or renal system, herein termed "Severe4," had the greatest impact on post-CART survival. Controlling for other prognostic factors (number of prior therapies, Eastern Cooperative Oncology Group performance status, BCL6 translocation, and molecular subtype), Severe4 was strongly associated with shorter PFS and OS in the LC and in an independent single-center validation cohort (VC). Severe4 was also a significant predictor of grade ≥3 cytokine release syndrome in the LC, while maintaining this trend in the VC. Thus, our results indicate that adverse outcomes for patients with DLBCL meant to receive CART can be predicted using a simplified CIRS-derived comorbidity index.

A Novel CDK2/9 Inhibitor CYC065 Causes Anaphase Catastrophe and Represses Proliferation, Tumorigenesis, and Metastasis in Aneuploid Cancers

Cyclin-dependent kinase 2 (CDK2) antagonism inhibits clustering of excessive centrosomes at mitosis, causing multipolar cell division and apoptotic death. This is called anaphase catastrophe. To establish induced anaphase catastrophe as a clinically tractable antineoplastic mechanism, induced anaphase catastrophe was explored in different aneuploid cancers after treatment with CYC065 (Cyclacel), a CDK2/9 inhibitor. Antineoplastic activity was studied in preclinical models. CYC065 treatment augmented anaphase catastrophe in diverse cancers including lymphoma, lung, colon, and pancreatic cancers, despite KRAS oncoprotein expression. Anaphase catastrophe was a broadly active antineoplastic mechanism. Reverse phase protein arrays (RPPAs) revealed that along with known CDK2/9 targets, focal adhesion kinase and Src phosphorylation that regulate metastasis were each repressed by CYC065 treatment. Intriguingly, CYC065 treatment decreased lung cancer metastases in in vivo murine models. CYC065 treatment also significantly reduced the rate of lung cancer growth in syngeneic murine and patient-derived xenograft (PDX) models independent of KRAS oncoprotein expression. Immunohistochemistry analysis of CYC065-treated lung cancer PDX models confirmed repression of proteins highlighted by RPPAs, implicating them as indicators of CYC065 antitumor response. Phospho-histone H3 staining detected anaphase catastrophe in CYC065-treated PDXs. Thus, induced anaphase catastrophe after CYC065 treatment can combat aneuploid cancers despite KRAS oncoprotein expression. These findings should guide future trials of this novel CDK2/9 inhibitor in the cancer clinic.

Peri-CAR-T practice patterns and survival predictors for all CAR-T patients and post-CAR-T failure in aggressive B-NHL

Most patients receiving chimeric antigen receptor T-cell therapy (CAR-T) for aggressive B-cell non-Hodgkin lymphoma (B-NHL) do not experience a durable remission. Several novel agents are approved to treat relapsed, refractory aggressive B-NHL; however, it remains unclear how to sequence these therapies pre- and post-CAR-T. We conducted a multicenter retrospective analysis to describe peri-CAR-T practice patterns and survival predictors for patients receiving CD19-directed CAR-T. Patients (n = 514) from 13 centers treated with CAR-T for B-NHL between 2015-2021 were included in the study. Survival curves were constructed using Kaplan-Meier method. Multivariate Cox regression analysis was used to determine the impact of the variables on survival outcomes. For all patients receiving CAR-T, a greater number of lines of therapy pre-CAR-T apheresis and bridging therapy were predictive of inferior progression-free survival (PFS) and overall survival (OS). The median PFS and OS from the time of CAR-T cell infusion were 7.6 and 25.6 months, respectively. From the time of progression post-CAR-T, the median OS was 5.5 months. The median PFS of treatments administered in the first-line post-CAR-T failure was 2.8 months. Patients with refractory disease on day 30 had inferior OS and were less likely to receive subsequent treatment(s) than other patients with CAR-T failure. Allogeneic hematopoietic cell transplantation for selected patients at any time following CAR-T failure led to durable responses in over half of patients at 1 year. These data provide a benchmark for future clinical trials in patients with post-CAR-T cell progression, which remains an unmet clinical need.

Patient characteristics that predict Richter's transformation in patients with chronic lymphocytic leukemia treated with ibrutinib

Chronic lymphocytic leukemia (CLL) transformation to aggressive lymphoma, known as Richter's Transformation (RT), has a dismal prognosis. There are limited data evaluating risk of RT in patients treated with ibrutinib. We performed a retrospective analysis to determine prognostic variables associated with development of RT and overall survival (OS) at progression after treatment with ibrutinib. We identified 559 patients with CLL treated with ibrutinib from 2010-2019. After a median follow-up of 44.5 months from ibrutinib start, 179 patients progressed and were included in our analysis. After a median follow-up of 20.8 months from progression, 54 out of 179 patients developed RT. Progression on treatment (hazard ratio [HR] 4.01 [1.60-10.00], p = .003), higher LDH (HR 1.80 for 2-fold increase [1.33-2.43], p = .0001), and lymphadenopathy without lymphocytosis (HR 2.88 [1.15-7.20], p = .02) were independent prognostic variables for the development of RT at progression. Progression with lymphadenopathy without lymphocytosis continued to be an independent prognostic variable of worse OS post-progression. In a subset analysis of 50 patients who obtained a PET-CT at progression, the median SUV_max for patients who would develop RT was 15.2 (n = 30, range: 4.0-46.3) versus those patients who did not develop RT with a SUV_max of 7.7 (n = 20, range: 2.3-27.2) (p = .0030). Median OS from date of RT was 4.0 months, suggesting that prognosis for RT remains poor. A lymph node biopsy to rule out RT should be considered in patients who received ibrutinib who progress on treatment, have an elevated LDH, or progress with lymphadenopathy without lymphocytosis.

NEDD8-activating enzyme inhibition induces cell cycle arrest and anaphase catastrophe in malignant T-cells

Peripheral T-cell lymphoma (PTCL) is characterized by poor outcomes. We and others have shown that targeting the NEDD8-activating enzyme (NAE) with an investigational inhibitor pevonedistat deregulates cell cycle and mitosis in lymphoma and leukemia. Here, we report that PTCL is characterized by increased rate of chromosomal instability. NAE inhibition promotes cell cycle arrest and induces multipolar anaphases in T-cell lymphoma cell lines, resulting in apoptosis, also observed in primary malignant PTCL cells treated with pevonedistat. We identified p27^Kip1 as a mediator of anaphase catastrophe in these cells. Targeting neddylation with pevonedistat may be a promising approach to treatment of PTCL.

Richter's Transformation

PURPOSE OF REVIEW

Richter's transformation (RT) occurs when chronic (CLL) transforms into an aggressive lymphoma. Despite improvements in the treatment of CLL, prognosis for RT remains poor. Here, we review current literature of RT, with a focus on novel treatment options.

RECENT FINDINGS

Efforts are underway to improve outcomes for patients with RT. While small molecule inhibitors have limited efficacy as monotherapy, recent developments combining them with chemo-immunotherapy show promise. Studies exploring the use of cellular therapies including chimeric antigen receptor T-cells and bispecific antibodies are ongoing. The current treatment paradigm for RT is to enroll these patients on a clinical trial when available, together with consultation for a consolidative allogeneic stem cell transplant. Trials investigating novel combinations and cellular therapy are ongoing. Determining predictive variables of transformation is imperative to design studies that allow for early identification and intervention for patients with RT.

Assessment of Salvage Regimens Post CAR-T Cell Therapy for Patients with Diffuse Large B-Cell Lymphoma

BACKGROUND

Anti-CD19 chimeric antigen receptor T-cell therapy (CAR19) represents a critical treatment modality for patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL). However, the majority of patients will subsequently experience disease progression following CAR19 and there is limited data assessing the best salvage regimen for these patients.

OBJECTIVE

To evaluate outcomes in DLBCL patients with progressive disease post CAR19 and to assess variables that predict response to salvage therapy.

STUDY DESIGN

We performed a retrospective analysis of all patients with DLBCL who received CAR19 at our institution from January 2018 to February 2021. Demographics, disease characteristics, best response to CAR19, date of relapse or progression, and first salvage therapy and response to salvage were also collected. We analyzed patients according to whether they responded to CAR19 (responders) or did not (non-responders). Salvage regimens were classified into 6 groups for analysis. Primary endpoints included overall survival (OS) and progression free survival (PFS), calculated using the Kaplan Meier method. Cox models were fit to evaluate the effect of prognostic factors.

RESULTS

Of the 120 patients who received CAR19 during the analysis period, 69 patients achieved a CR/PR to CAR19 (responders), 44 patients achieved SD/PD to CAR19, and 7 died before assessment (51 non-responders). 30 responders relapsed and 26 received salvage therapy, while 24 non-responders received salvage. The primary salvage regimens that were utilized included lenalidomide-based regimens (n=17, 34%), BTKi (n=10, 20%), checkpoint inhibitor based (n=7, 14%), chemo-immunotherapy (n=5, 10%), allo (n=5, 10%), and other (n=6, 12%). There was no significant difference in OS based on salvage regimen (p=0.4545). Responders who received salvage had significantly longer OS compared to non-responders (median OS not reached vs. 10.9 months; p=0.0187), and response to CAR19 and elevated lactate dehydrogenase (LDH) level at time of salvage treatment were the only two statistically significant prognostic factors after accounting for other variables.

CONCLUSION

Outcomes for responders to CAR19 are significantly better with salvage therapy as compared to non-responders to CAR19. There was no significant difference in outcomes seen based on salvage regimen in our study. Future research is needed to assess the best salvage regimen post CAR19 failure.

A matching-adjusted indirect comparison of acalabrutinib versus zanubrutinib in relapsed or refractory chronic lymphocytic leukemia

Video Abstract

A novel somatic PLCG2 variant associated with resistance to BTK and SYK inhibition in chronic lymphocytic leukemia

The treatment of chronic lymphocytic leukemia (CLL) has been transformed by the use of targeted small molecules inhibiting components of the B cell receptor (BCR) signaling pathway (Haematologica, 103, 2018 and e204; Curr Hematol Malig Rep, 14, 2019, 302). Chief among these is ibrutinib, an irreversible inhibitor of Bruton tyrosine kinase (BTK), which produces deep, durable responses in CLL with good tolerability (Haematologica, 103, 2018 and e204). Though prolonged exposure to the drug can exert selective pressure on CLL cells and allow for the emergence of drug-resistant clones, primary ibrutinib treatment failure is rare (Expert Rev Hematol, 11 and 2018, 185; N Engl J Med, 370, 2014 and 2352; N Engl J Med, 373, 2015 and 25, 2425; Blood, 128, 2016 and 2199). Activating mutations in the gene PLCG2, which encodes a downstream target of BTK, appear to enable constitutive BCR signaling and have been associated with ibrutinib resistance (Int J Cancer, 146 and 2020, 85; J Clin Oncol, 35, 2017 and 1437; Blood, 126, 2015 and 61). In recent years, novel investigational agents have targeted other components of the BCR pathway. Among these is entospletinib, an orally bioavailable, selective inhibitor of splenic tyrosine kinase (SYK) (Blood, 126, 2015 and 1744), which lies upstream of the enzyme phospholipase C-gamma-2 (PLCG2). Here, we describe a patient who was found to harbor a novel somatic variant of PLCG2 and experienced a lack of treatment response to both ibrutinib and entospletinib.

Anti-CD19 Chimeric Antigen Receptor T-Cell Therapy for Richter Transformation: An International, Multicenter, Retrospective Study

PURPOSE

Outcomes for Richter transformation (RT) are poor with current therapies. The efficacy and safety of anti-CD19 chimeric antigen receptor T-cell therapy (CAR-T) for RT are not established.

METHODS

We performed an international multicenter retrospective study of patients with RT who received CAR-T. Patient, disease, and treatment characteristics were summarized using descriptive statistics, and modeling analyses were used to determine association with progression-free survival (PFS) and overall survival (OS). PFS and OS were estimated from the date of CAR-T infusion.

RESULTS

Sixty-nine patients were identified. The median age at CAR-T infusion was 64 years (range, 27-80). Patients had a median of four (range, 1-15) previous lines of therapy for CLL and/or RT, including previous Bruton tyrosine kinase inhibitor and/or BCL2 inhibitor therapy in 58 (84%) patients. The CAR-T product administered was axicabtagene ciloleucel in 44 patients (64%), tisagenlecleucel in 17 patients (25%), lisocabtagene maraleucel in seven patients (10%), and brexucabtagene autoleucel in one patient (1%). Eleven patients (16%) and 25 patients (37%) experienced grade ≥3 cytokine release syndrome and immune effector cell-associated neurotoxicity syndrome, respectively. The overall response rate was 63%, with 46% attaining a complete response (CR). After a median follow-up of 24 months, the median PFS was 4.7 months (95% CI, 2.0 to 6.9); the 2-year PFS was 29% (95% CI, 18 to 41). The median OS was 8.5 months (95% CI, 5.1 to 25.4); the 2-year OS was 38% (95% CI, 26 to 50). The median duration of response was 27.6 months (95% CI, 14.5 to not reached) for patients achieving CR.

CONCLUSION

CAR-T demonstrates clinical efficacy for patients with RT.

Utilizing risk factors to guide treatment decisions in chronic lymphocytic leukemia

INTRODUCTION

In the era of chemo-immunotherapy, high-risk factors unequivocally predicted inferior outcomes for patients with CLL. The widespread adoption of BTK inhibitors has challenged the practical implications of such testing, as many patients have improved outcomes despite the presence of high-risk features. The impact of adverse prognostic factors, such as unmutated IGHV, on survival has been ameliorated by continuous treatment with BTK inhibitors, but not by finite-duration therapy with venetoclax-based combinations. Furthermore, TP53 abnormalities continue to be associated with worse outcomes in the era of novel agents. New treatment modalities, such as pirtobrutinib, lisocabtagene maraleucel, and ongoing studies combining BTK inhibitors with venetoclax, raise new questions on the significance of prognostic factors of survival for patients with CLL.

AREAS COVERED

Herein, we summarized the available literature on patients with CLL harboring high-risk biomarkers, with a focus on data from key clinical trials.

EXPERT OPINION

Testing for prognostic biomarkers will remain relevant to identify patients who may have increased benefit from novel therapeutic strategies, such as combination therapies and novel agents. Patients with high-risk disease should be encouraged to participate in clinical trials.

Treatment of Richter's Transformation with Novel Therapies

PURPOSE OF REVIEW

This review presents recently published clinical trial data and ongoing investigations regarding the treatment of Richter's transformation (RT).

RECENT FINDINGS

Recently, numerous approaches have been investigated for the treatment of RT including: traditional chemoimmunotherapy regimens combined with targeted agents such as BTKi and BCL2i; immunotherapy combined with targeted agents; non-covalent BTKis; bispecific T cell engagers; and CART therapy. In addition, various novel targeted agents are currently being studied for the treatment of RT in phase 1 and 2 clinical trials. Standard of care treatment with chemoimmunotherapy for RT has limited efficacy in achieving durable remissions. Here, we review recent data on the use of combination treatments and targeted agents in RT. Although some progress has been made in the investigation to optimize treatment of RT, further study is needed to evaluate long term outcomes of recently published trials and test efficacy of upcoming novel agents.

Gonadotropin-Releasing Hormone Antagonists in Prostate Cancer

Androgen deprivation therapy (ADT) comes in several forms, such as surgical castration or medical castration using gonadotropin-releasing hormone (GnRH) agonist or GnRH antagonist therapy. ADT is a critical treatment for high-risk and metastatic prostate cancer. There are important differences between GnRH agonists and antagonists. Here we review the mechanism of action between GnRH agonists and antagonists and the studies that led to the approval of degarelix. We also comment on the potential risks and benefits of degarelix, particularly when it comes to cardiovascular health. Finally, we describe an oral GnRH antagonist, which is not currently used in prostate cancer, but is included for completeness.

Postinfusion PD-1+ CD8+ CAR T cells identify patients responsive to CD19 CAR T-cell therapy in non-Hodgkin lymphoma

ABSTRACT

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized treatment for relapsed/refractory B-cell non-Hodgkin lymphoma (NHL). Robust biomarkers and a complete understanding of CAR T-cell function in the postinfusion phase remain limited. Here, we used a 37-color spectral flow cytometry panel to perform high dimensional single-cell analysis of postinfusion samples in 26 patients treated with CD28 costimulatory domain containing commercial CAR T cells for NHL and focused on computationally gated CD8+ CAR T cells. We found that the presence of postinfusion Programmed cell death protein 1 (PD-1)+ CD8+ CAR T cells at the day 14 time point 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+ T cell factor 1 (TCF1)+ stem-like CAR T cells and PD-1+ T-cell immunoglobulin and mucin-domain containing-3 (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 cells and highlight the importance of PD-1 positivity in CD8+ CAR T cells after infusion in achieving CR.

Outcomes of CD19 CAR T in Transformed Indolent Lymphoma Compared to De Novo Aggressive Large B-Cell Lymphoma

Chimeric antigen receptor (CAR) T-cell therapy has revolutionized treatment of aggressive large B-cell lymphoma (aLBCL). Patients with transformed indolent non-Hodgkin lymphoma (tiNHL) were included in key CAR trials, but outcomes of CAR for this distinct, historically high-risk group are poorly understood. We conducted a multicenter retrospective study of 1182 patients with aLBCL receiving standard-of-care CAR T between 2017 and 2022, including 338 (29%) with tiNHL. Rates of grade ≥ 3 cytokine release syndrome (CRS) were similar between tiNHL and de novo cohorts (7% vs. 8%, p = 0.6), while grade ≥ 3 immune effector cell-associated neurotoxicity syndrome was lower in tiNHL (21% vs. 27%, p = 0.02). Overall response rate was similar in both cohorts (83% vs. 81%, p = 0.3), while complete response rate was higher in tiNHL (67% vs. 59%, p = 0.017). With a median follow-up of 22.3 months, the progression/relapse-free (PFS) and overall survival (OS) were similar between the tiNHL and de novo cohorts (24-month PFS 41% [95% CI: 35%-46%] vs. 38% [95% CI: 35%-42%]; 24-month OS 58% [95% CI: 52%-63%] vs. 52% [95% CI: 48%-56%], respectively). After adjusting for key risk factors, there was a trend toward a lower hazard of disease progression, relapse or death post-CAR for tiNHL patients compared to de novo aLBCL patients (HR: 0.84 [95% CI: 0.69-1.0], p = 0.07). Elevated LDH, advanced stage, prior bendamustine within 12 months of CAR, receipt of bridging therapy, CNS involvement, and ≥ 3 prior lines of therapy were each associated with inferior PFS. In conclusion, CAR T therapy is highly effective with an acceptable toxicity profile in patients with tiNHL.