Updated Results of Rituximab Pre- and Post-BEAM with or without 90Yttrium Ibritumomab Tiuxetan during Autologous Transplant for Diffuse Large B-cell Lymphoma

Radioligand Therapy in Lymphoma: Past, Present, and Future

In the1980s, radiolabeled cells helped understand the pathology of hemato-oncology. In the 1990s, preclinical trials evaluated radiolabeled immunotherapy with monoclonal antibodies (MoAbs) such as anti-CD20 agents labeled with Iodine-131 (Bexxar) or Yttrium-90 (Zevalin). Due to the safe and durable responses of radiolabeled MoAbs, the Food and Drug Administration approved these agents in the 2000s. Despite radioimmunotherapy's long journey, its application has recently decreased. This review will discuss the historical timeline of radioimmunotherapy, debate on advantages and difficulties, and explore trials. We will examine future directions of radioligand therapy in hemato-oncology, considering emerging molecules that may become the next theragnostic trend.

A paradox of choice: Sequencing therapy in relapsed/refractory diffuse large B-cell lymphoma

The available treatments for relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) have experienced a dramatic change since 2017. Incremental advances in basic and translational science over several decades have led to innovations in immune-oncology. These innovations have culminated in eight separate approvals by the US Food and Drug Administration for the treatment of patients with R/R DLBCL over the last 10 years. High-dose therapy and autologous stem cell transplant (HDT-ASCT) remains the standard of care for transplant-eligible patients who relapse after an initial remission. For transplant-ineligible patients or for those who relapse following HDT-ASCT, multiple options exist. Monoclonal antibodies targeting CD19, antibody-drug conjugates, bispecific antibodies, immune effector cell products, and other agents with novel mechanisms of action are now available for patients with R/R DLBCL. There is increasing use of chimeric antigen receptor (CAR) T-cells as second-line therapy for patients with early relapse of DLBCL or those who are refractory to initial chemoimmunotherapy. The clinical benefits of these strategies vary and are influenced by patient and disease characteristics, as well as the type of prior therapy administered. Therefore, there are multiple clinical scenarios that clinicians might encounter when treating R/R DLBCL. An optimal sequence of drugs has not been established, and there is no evidence-based consensus on how to best order these agents. This abundance of choices introduces a paradox: proliferating treatment options are initially a boon to patients and providers, but as choices grow further they no longer liberate. Rather, more choices make the management of R/R DLBCL more challenging due to lack of direct comparisons among agents and a desire to maximize patient outcomes. Here, we provide a review of recently-approved second- and subsequent-line agents, summarize real-world data detailing the use of these medicines, and provide a framework for sequencing therapy in R/R DLBCL.

Clinical relevance of MYC/BCL2 expression and cell of origin in patients with diffuse large b-cell lymphoma treated with autologous transplant

Dual expression of MYC and BCL2 proteins (double-expressor lymphoma [DEL]) as well as cell of origin (COO) are important prognostic factors in patients with diffuse large B-cell lymphoma (DLBCL) after conventional chemotherapy. We studied the prognostic impact of DEL and COO in patients with relapsed DLBCL treated with autologous stem cell transplant (ASCT). Three-hundred and three patients with stored tissue samples were identified. Classification was successful in 267 patients: 161 (60%) were DEL/non-double hit (DHL), 98 (37%) were non-DEL/non-DHL, and 8 (3%) were DEL/DHL. Compared to non-DEL/non-DHL, DEL/DHL had worse overall survival while DEL/non-DHL did not significantly differ in overall survival. On multivariable analysis, DEL/DHL, age >60 years, and >2 prior therapies, but not COO, were important prognostic factors for overall survival. When we explored the interaction of COO and BCL2 expression, patients with germinal center B-cell (GCB)/BCL2 (+) had inferior progression-free survival (PFS) compared to GCB/BCL2 (-) patients (HR, 4.97; P = 0.027). We conclude that the DEL/non-DHL and non-DEL/non-DHL subtypes of DLBCL have similar survival after ASCT. The negative impact of GCB/BCL2 (+) on PFS warrants future trials targeting BCL2 after ASCT. The inferior outcomes in DEL/DHL need to be verified in a larger number of patients.

Results of a Phase II Trial of Allogeneic Hematopoietic Stem Cell Transplantation Using 90Y-Ibritumomab Tiuxetan (Zevalin) in Combination With Fludarabine and Melphalan in Patients With High-Risk B-Cell Non-Hodgkin's Lymphoma

BACKGROUND

Allogeneic hematopoietic stem cell transplantation (alloHCT) is potentially curative for relapsed/refractory (r/r) B-cell non-Hodgkin's lymphoma (B-cell NHL). However, relapse remains a major cause of treatment failure, especially in patients with either positron emission tomography (PET)-positive and/or chemoresistant disease prior to alloHCT. 90Y-ibritumomab tiuxetan (Zevalin) is a radiolabeled anti-CD20 antibody which is a safe and effective therapy in multiple histologic subtypes of B-cell NHL and has also been incorporated in both autologous HCT (autoHCT) and alloHCT conditioning regimens.

OBJECTIVES

The purpose of this study was to evaluate the efficacy and confirm the safety of the radiolabeled anti-CD20 antibody ibritumomab tiuxetan (Zevalin) combined with the reduced intensity conditioning (RIC) regimen of fludarabine and melphalan (Flu/Mel) in patients with high-risk B-cell NHL.

STUDY DESIGN

We conducted a phase II trial (NCT00577278) of Zevalin with Flu/Mel in patients with high-risk B-cell NHL. We enrolled 41 patients from October 2007 to April 2014, all of whom had either a fully matched sibling or 8/8 or 7/8 matched unrelated donor (MUD). Patients received 111In-Zevalin (5.0 mCi) on day -21 pre-HCT, followed by 90Y-Zevalin (0.4 mCi/kg) on day -14. Fludarabine (25 mg/m2 daily) was given from days -9 to -5 and melphalan (140 mg/m2) was administered on day -4. All patients received rituximab 250 mg/m2 on day +8 and an additional dose on either day +1 or -21 depending on the baseline rituximab level. Patients with a low rituximab level were given rituximab on days -21 and -15. All patients received tacrolimus/sirolimus (T/S) with or without methotrexate (MTX) for graft-versus-host disease (GVHD) prophylaxis starting on day -3, and stem cells were infused on day 0.

RESULTS

The 2-year overall survival (OS) and progression-free survival (PFS) for all patients were 63% and 61%, respectively. The incidence of relapse at 2 years was 20%. Nonrelapse mortality (NRM) at day +100 and 1 year were 5% and 12%, respectively. The overall cumulative incidence of grade II-IV and III-IV acute GVHD (aGVHD) were 44% and 15%, respectively. Extensive chronic GVHD (cGVHD) occurred in 44% of patients. On univariate analysis, histology (diffuse large B cell lymphoma (DLBCL) vs. others) was negatively predictive for OS (P = .0013) and PFS (P = .0004), while histology (DLBCL vs. others, P = .0128) predicted for relapse. PET positivity pre-HCT did not correlate with any of the efficacy endpoints.

CONCLUSION

Addition of Zevalin to Flu/Mel is safe and effective in high-risk NHL and met the prespecific endpoint. Results were suboptimal in patients with DLBCL.

Chimeric antigen receptor T-cell therapy is superior to standard of care as second-line therapy for large B-cell lymphoma: A systematic review and meta-analysis

Treatment with high-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is considered standard of care (SOC) second-line treatment for relapsed or refractory large B-cell lymphoma (LBCL). However, outcomes remain suboptimal. A systematic review and meta-analysis of randomised controlled trials comparing efficacy and safety of SOC versus chimeric antigen receptor T-cell (CAR-T) therapy as second-line for patients with LBCL refractory or relapsing within 12 months. Outcomes included overall survival (OS), event-free survival (EFS), overall response rate (ORR) and safety. Three trials published in 2021 (involving 865 participants) fulfilled the eligibility criteria. EFS as well as OS were significantly improved with CAR-T therapy as compared to SOC, hazard ratio (HR) 0.57 (95% confidence interval [CI] 0.49-0.68) and HR 0.77 (95% CI 0.60-0.98) respectively. CAR-T therapy was associated with significantly better ORR, relative risk (RR) 1.55 (95% CI 1.12-2.13, p = 0.001). The risk of Grade III/IV adverse event was comparable between the two arms, RR 1.03 (95% CI 0.93-1.14). In summary, CAR-T therapy has superior outcomes as compared to SOC in patients with LBCL refractory or relapsing within 12 months, without excess of toxicity. Longer follow-up is needed to confirm these results and determine the optimal sequencing of CAR-T therapy in the management of LBCL.

Nine-Year Follow-up of Patients with Relapsed Follicular Lymphoma after Nonmyeloablative Allogeneic Stem Cell Transplant and Autologous Transplant

PURPOSE

To compare outcomes between patients with relapsed follicular lymphoma who received a nonmyeloablative allogeneic stem cell transplant (alloSCT) and those who received an autologous transplant (autoSCT).

PATIENTS AND METHODS

We evaluated 194 patients with follicular lymphoma who received an alloSCT (n = 98) or autoSCT (n = 96) at MD Anderson Cancer Center (Houston, TX). The transplant type used was based on donor availability and by Medicare reimbursement guidelines. Patients who received an alloSCT were enrolled in four consecutive trials in which they received fludarabine, cyclophosphamide (or bendamustine), and rituximab conditioning. autoSCT patients received R-BEAM (rituximab, carmustine, etoposide, cytarabine, and melphalan).

RESULTS

The median follow-up of survivors was 108 months for the alloSCT group and 102 months for the autoSCT group. Overall survival was significantly better for patients who received an alloSCT compared with those who received an autoSCT (62% vs. 46%; P = 0.048). Similarly, progression-free survival rates were 52% in patients who received an alloSCT and 31% in those who received an autoSCT (P < 0.001), and the 8-year relapse rates were 11% and 43%, respectively (P < 0.0001). Only three patients in the alloSCT group relapsed beyond 3.5 years. In the alloSCT group, the rates for grade 2 to 4 acute graft-versus-host disease (GVHD), grade 3 to 4 acute GVHD, and extensive chronic GVHD were 22%, 9%, and 38%, respectively. In the autoSCT group, the 8-year incidence of secondary myelodysplasia was 11%. Nonrelapse mortality was similar between the two groups (15% vs. 11% at 8 years; P = 0.27).

CONCLUSIONS

This study shows that alloSCT is curative and confers superior survival compared with autoSCT in patients with follicular lymphoma.

Strategies to improve outcomes of autologous hematopoietic cell transplant in lymphoma

High-dose chemotherapy and autologous hematopoietic cell transplantation (HDT-AHCT) remains an effective therapy in lymphoma. Over the past several decades, HDT with BEAM (carmustine, etoposide, cytarabine, and melphalan) and CBV (cyclophosphamide, carmustine, and etoposide) have been the most frequently used preparatory regimens for AHCT in Hodgkin (HL) and non-Hodgkin lymphoma (NHL). This article reviews alternative combination conditioning regimens, as well as novel transplant strategies that have been developed, to reduce transplant-related toxicity while maintaining or improving efficacy. These data demonstrate that incorporation of maintenance therapy posttransplant might be the best way to improve outcomes.

Allogeneic Transplantation after Myeloablative Rituximab/BEAM ± Bortezomib for Patients with Relapsed/Refractory Lymphoid Malignancies: 5-Year Follow-Up Results

Although bortezomib and rituximab have synergistic activity in patients with lymphoma and both can attenuate graft-versus-host disease (GVHD), the drugs have not been used together in patients undergoing allogeneic stem cell transplantation (alloSCT). In this phase I/II trial, we assessed the safety and activity of bortezomib added to the rituximab (R) plus BEAM (carmustine, etoposide, cytarabine, melphalan) regimen in patients with relapsed lymphoma undergoing alloSCT. Primary GVHD prophylaxis consisted of tacrolimus and methotrexate. Bortezomib (1 to 1.3 mg/m² per dose) was administered i.v. on days -13, -6, -1, and +2. We performed inverse probability weighting analysis to compare GVHD and survival results with an historical control group that received R-BEAM without bortezomib. Thirty-nine patients were assessable for toxic effects and response. The median age was 54 years. The most common diagnosis was diffuse large B cell lymphoma (41%). Twenty-two patients (56%) and 17 patients (44%) received their transplants from matched related and matched unrelated donors, respectively. The maximum tolerated bortezomib dose was 1 mg/m². The weighted cumulative incidences of grades II to IV and III or IV acute GVHD were 50% and 34%, respectively; these incidences and survival rates were not significantly different from those of the control group. Median survival was not reached in patients age ≤ 50 years and with a long follow-up time of 60.7 months. The R-BEAM regimen has a survival benefit in lymphoma patients age ≤ 50 years undergoing alloSCT. The addition of bortezomib has no impact on survival or incidence of GVHD.