Fludarabine-melphalan as a preparative regimen for reduced-intensity conditioning allogeneic stem cell transplantation in relapsed and refractory Hodgkin's lymphoma: the updated M.D. Anderson Cancer Center experience

Immunotherapy in hematologic malignancies: achievements, challenges and future prospects

The immune-cell origin of hematologic malignancies provides a unique avenue for the understanding of both the mechanisms of immune responsiveness and immune escape, which has accelerated the progress of immunotherapy. Several categories of immunotherapies have been developed and are being further evaluated in clinical trials for the treatment of blood cancers, including stem cell transplantation, immune checkpoint inhibitors, antigen-targeted antibodies, antibody-drug conjugates, tumor vaccines, and adoptive cell therapies. These immunotherapies have shown the potential to induce long-term remission in refractory or relapsed patients and have led to a paradigm shift in cancer treatment with great clinical success. Different immunotherapeutic approaches have their advantages but also shortcomings that need to be addressed. To provide clinicians with timely information on these revolutionary therapeutic approaches, the comprehensive review provides historical perspectives on the applications and clinical considerations of the immunotherapy. Here, we first outline the recent advances that have been made in the understanding of the various categories of immunotherapies in the treatment of hematologic malignancies. We further discuss the specific mechanisms of action, summarize the clinical trials and outcomes of immunotherapies in hematologic malignancies, as well as the adverse effects and toxicity management and then provide novel insights into challenges and future directions.

Improved survival after single-unit cord blood transplantation using fludarabine and melphalan-based reduced-intensity conditioning for malignant lymphoma: impact of melphalan dose and graft-versus-host disease prophylaxis with mycophenolate mofetil

We evaluated 413 adult patients with lymphoma who underwent unrelated cord blood transplantation (UCBT) with fludarabine and melphalan (FM)-based reduced-intensity conditioning between 2002 and 2017 to investigate longitudinal changes in outcomes and the optimal melphalan dose and graft-versus-host disease (GVHD) prophylaxis regimen. Outcomes were compared between FM80/100 (melphalan dose: 80 or 100 mg/m²) and FM140 (melphalan dose: 140 mg/m²), as well as between calcineurin inhibitor (CNI) plus methotrexate (MTX), CNI plus mycophenolate mofetil (MMF), and CNI alone. The 3-year overall survival (OS) and non-relapse mortality (NRM) rates improved over time (OS: 27% in 2000s vs. 42% in 2010s, p < 0.001; NRM: 43% in 2000s vs. 26% in 2010s, p < 0.001). Multivariable analysis showed that in the 2000s, melphalan dose and GVHD prophylaxis regimen did not affect any outcomes. In the 2010s, FM80/100 (vs. FM140) related to better OS (hazard ratio [HR] 0.62, p = 0.01) and NRM (HR 0.52, p = 0.016). MTX + CNI and CNI alone (vs. CNI + MMF) related to worse OS (CNI + MTX, HR 2.01, p < 0.001; CNI alone, HR 2.65, p < 0.001) and relapse/progression (CNI + MTX, HR 2.40, p < 0.001; CNI alone, HR 2.13, p = 0.023). In recent years, the use of FM80/100 and CNI + MMF significantly reduced the risk of NRM and relapse/progression, respectively, and resulted in better OS after UCBT for lymphoma.

Favorable outcomes of allogeneic hematopoietic stem cell transplantation with fludarabine-bendamustine conditioning and posttransplantation cyclophosphamide in classical Hodgkin lymphoma

INTRODUCTION

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative treatment for patients with relapsed and refractory classic Hodgkin lymphoma (rrHL). However, the optimal conditioning regimen and GVHD prophylaxis for rrHL remain undetermined. The aim of this study was to investigate outcomes of allo-HSCT with a fludarabine plus bendamustine (FluBe) conditioning regimen and GVHD prophylaxis with posttransplantation cyclophosphamide (PTCY) in patients with rrHL.

METHODS

Allo-HSCT results in 58 adult patients with rrHL were analyzed retrospectively.

RESULTS

Three-year overall survival and event-free survival were 81% (95% CI 65-91) and 55% (95% CI 38-72), respectively. The cumulative incidence of relapse (CIR) at 3 years was 33% (95% CI 13-51). The cumulative incidence of aGVHD grade II-IV and severe aGVHD grade III-IV was 36% (95% CI 22-48) and 22% (95% CI 9-33), respectively. The cumulative incidence of cGVHD was 32% (95% CI 17-45), including moderate or severe cGVHD in 17% (95% CI 4-28). Patients who developed aGVHD after allo-HSCT had significantly lower CIR (24% vs 49%, p = 0.004). The use of PBSC as a graft source also significantly reduced CIR (4% vs 61%, p = 0.002).

CONCLUSIONS

FluBe-PTCY allo-HSCT facilitates favorable outcomes, low toxicity, and mortality in rrHL.

Reappraising the Role of Allogeneic Hematopoietic Stem Cell Transplantation in Relapsed and Refractory Hodgkin’s Lymphoma: Recent Advances and Outcomes

Hodgkin’s lymphoma is a rare yet highly curable disease in the majority of patients treated with modern chemotherapy regimens. For patients who fail to respond to or relapse after initial systemic therapies, treatment with high-dose chemotherapy and autologous hematopoietic stem cell transplantation can provide a cure for many with chemotherapy-responsive lymphoma. Patients who relapse after autologous transplant or those with chemorefractory disease have poor prognosis and represent a high unmet need. Allogeneic hematopoietic stem cell transplantation provides a proven curative therapy for these patients and should be considered, especially in young and medically fit patients. The use of newer agents in this disease such as brentuximab vedotin and immune checkpoint inhibitors can help bring more patients to transplantation and should be considered as well.

Haploidentical Hematopoietic Stem Cell Transplant Using Post-transplant Cyclophosphamide: A Single-Center Initial Experience in Vietnam

AIMS AND OBJECTIVES

Haploidentical transplants constitute a potential alternative therapy for patients who urgently need transplantation in the absence of human leukocyte antigen-matched donors. We report a single-center experience regarding the initial results of haploidentical peripheral blood stem cell transplantation (haplo-PBSCT) using post-transplant cyclophosphamide (PTCy) at the HCMC Blood Transfusion Hematology (BTH) Hospital.

METHODS

We conducted a retrospective case series study of 23 patients who underwent haplo-PBSCT using PTCy at the HCMC BTH Hospital between January 2014 and January 2021. The refined disease risk index (DRI) was used to stratify the outcomes. We evaluated the engraftment rate, graft-versus-host disease (GVHD), and complications during haploidentical transplantation. Overall survival (OS), disease-free survival (DFS), and GVHD-free relapse-free survival (GRFS) were assessed.

RESULTS

The majority of the patients in the present study were diagnosed with acute myeloid leukemia. All patients received reduced-intensity conditioning regimens. The engraftment rate was 86.9%. The median times to neutrophil and platelet engraftment were 17 and 31 days, respectively. Two patients (8.7%) reported severe acute GVHD (grade III-IV), while two patients (8.7%) had grade I-II acute GVHD. Three patients experienced limited chronic GVHD of the skin, requiring topical steroids. The most common complication was bloodstream infection (60.9%). Cytomegalovirus reactivation occurred in 19 patients (82.6%) and 17.4% developed hemorrhagic cystitis. The 1-year relapse rate was 32.5%. The cumulative incidence of non-relapse mortality at 1 year was 17.3%. The 1-year OS and DFS rates were 66.3% and 55.7%, respectively. The 1-year GRFS rate was 49.2%. A high/very high DRI score was associated with worse OS after haplo-PBSCT (P=0.038).

CONCLUSION

Haploidentical transplant using PTCy is a feasible therapy for patients without suitably matched donors in Vietnam. Infection after transplantation remains a challenge and requires effective management.

Allogeneic Stem Cell Transplantation for Relapsed and Refractory Hodgkin Lymphoma: Real World Experience of a Single Center

Introduction: Refractory and relapsed Hodgkin lymphoma (R/R HL) is associated with poor prognosis, and allogeneic stem cell transplantation (allo-SCT) remains the only potentially curative approach.

Aim: The aim of the study was to evaluate the feasibility of allotransplantation in R/R HL setting.

Material: Overall, 24 patients (17 men and 7 women) at a median age of 27 years (range 18–44) underwent allo-SCT between 2002 and 2020.

Results: Nineteen patients received prior autologous stem cell transplantation (ASCT1) whereas eight patients received second ASCT (ASCT2) after failure of ASCT1. Six patients received only brentuximab vedotin (BV; n = 4) or BV followed by checkpoint inhibitors (CPI; n = 2) before entering allo-SCT. Median time from ASCT1 to allo-SCT was 17.1 months. Fifteen patients received grafts from unrelated donors. Peripheral blood was a source of stem cells for 16 patients. Reduced-intensity conditioning was used for all patients. Disease status at transplant entry was as follows: complete remission (CR; n = 4), partial response (PR; n = 10), and stable disease (SD; n = 10). Acute and chronic graft-versus-host disease (GVHD) developed in 13 (54%) and 4 (16%) patients, respectively. Median follow-up for the entire cohort was 13.3 months. At the last follow-up, 17 (71%) patients died. The main causes of death were disease progression (n = 10), infectious complications (n = 6), and steroid-resistant GVHD (n = 1). Non-relapse mortality at 12 months was 25%. At the last follow-up, seven patients were alive; six patients were in CR, and one had PR. The 2-year overall survival (OS) was 40%.

Conclusion: Chemosensitive disease at transplant was associated with better outcome. Allo-SCT allows for long-term survival in refractory and relapsed HL.

Salvage Therapy for Hodgkin's Lymphoma: A Review of Current Regimens and Outcomes

Relapse/refractory Hodgkin lymphoma patients are still a clinical concern. Indeed, despite more effective first-line chemotherapy regimens and better stratification of unresponsive patients by clinical factors and use of early PET, roughly one-third of such patients need salvage chemotherapy and consolidation with high-dose chemotherapy. In this paper, the authors review the different salvage treatments, with special emphasis on newer combinations with brentuximab vedotin or check point inhibitors. The overall response rate is constantly increasing, with a complete remission rate approaching 80%. Functional response evaluation by PET imaging is a strong predictive factor of longer survival, and more sophisticated tools, such as detection of circulating tumour DNA, are emerging to refine the disease-status assessment after treatment. Consolidation by high-dose chemotherapy is still considered the standard of care in chemosensitive patients, leading to a high fraction of patients towards long-term disease control. Maintenance therapy with BV is now approved, reducing disease relapse/progression. An increasing number of Hodgkin lymphoma patients will be cured after first- and second-line therapy, and long-term toxicity needs to be continuously assessed and avoided.

Second autologous stem cell transplantation for relapsed/refractory Hodgkin lymphoma after a previous autograft: a study of the lymphoma working party of the EBMT

The purpose of this study was to analyze the results of second autologous hematopoietic stem cell transplantation (ASCT2) for patients with relapsed/refractory Hodgkin lymphoma (HL) after a first transplantation (ASCT1). Outcomes for 56 patients receiving an ASCT2 registered in the EBMT database were analyzed. The 4-year cumulative incidences of non-relapse mortality and disease relapse/progression were 5% and 67%, respectively. The 4-year overall survival (OS) and progression-free survival (PFS) were 62% and 28%. In univariate analysis, relapse of HL within 12 months of ASCT1 was associated with a worse OS (35% versus 76%, p = 0.01) and PFS (19% versus 29%, p = 0.059). Chemosensitivity at ASCT2 predicted better outcomes (4-year OS 72% versus 29%, p = 0.002; PFS 31% versus 12%, p = 0.015). This series shows that ASCT2 is a safe procedure and a relatively effective option for patients with late relapses after ASCT1 and with chemosensitive disease who are not eligible for an allogeneic transplant.

Relapse of Hodgkin lymphoma after autologous hematopoietic cell transplantation: A current management perspective

Hodgkin lymphoma (HL) is a highly responsive disease with nearly 70% of patients experiencing cure after front-line chemotherapy. Patients who experience disease relapse receive salvage chemotherapy followed by consolidation with autologous hematopoietic cell transplantation (auto-HCT). Nearly 50% of patients relapse after an auto-HCT and constitute a subgroup with poor prognosis. Novel treatments such as immune checkpoint inhibitors and an anti-CD30 monoclonal antibody are currently approved for patients relapsing after auto-HCT; however, the duration of remission with these therapies remains limited. Allogeneic HCT is currently the only potentially curative treatment modality for patients relapsing after a prior auto-HCT. Early clinical trials with chimeric antigen receptor T-cell therapy targeting CD30 are underway for patients with relapsed/refractory HL and are already demonstrating safety and promising efficacy.

Relapsing/refractory HL after autotransplantation: which treatment?

For advanced-stage Hodgkin lymphoma (HL), front-line chemotherapy, alone or in combination with radiotherapy, leads to 5-year progression-free survival (PFS) rates and freedom-from-treatment failure (FFTF) rates of 70-85%, regardless of the chemotherapy regimen applied. Patients with HL experiencing disease progression during or within 3 months of front-line therapy (primary refractory) and patients whose disease relapses after a complete response have a second chance of treatment. The standard of care for relapsed or refractory HL is second-line chemotherapy followed by autologous stem cell transplantation (ASCT), which can induce long-term remission in approximately 40-50% of patients. However, HL recurrence occurs in about 50% of patients after ASCT, usually within the first year, and represents a significant therapeutic challenge. Allogeneic transplantation from HLA-matched donors represents the standard of care for patients with HL relapsing after- or refractory to ASCT.

Changes in patients population and characteristics of hematopoietic stem cell transplantation for relapsed/refractory Hodgkin lymphoma: an analysis of the Lymphoma Working Party of the EBMT

Indications for autologous (auto-HCT) and allogeneic transplantation (allo-HCT) in relapsed/refractory Hodgkin lymphoma (rrHL) have been long established. The expectation is that long-term outcomes have significantly improved over time with increased experience in these procedures. The objective of this study was to assess whether this is the case and to identify further areas of improvement. A total of 13,639 adult patients receiving an auto-HCT or allo-HCT for rrHL were reported to the European Society for Blood and Marrow Transplantation (EBMT) over a 25-year period. Regarding auto-HCT, recipients are younger, interval between diagnosis and transplant shorter, peripheral blood has become the universal stem cell source and the use of total body irradiation is almost non-existent in recent years. Allo-HCT is currently mostly used as a second transplant; recipients are younger, fitter and less frequently, chemorefractory. Reduced intensity conditioning protocols have vastly replaced myeloablative protocols. Increasing numbers of haplo-HCT have been reported. Both in auto-HCT and allo-HCT, NRM, PFS and OS have significantly improved but relapse remains the main cause of treatment failure. A better selection of patients and improvements in the supportive care has resulted in a reduction in the NRM. Relapse after HCT remains unchanged and further research is needed.

Outcome after autologous stem cell transplantation in primary refractory or relapsed Hodgkin lymphoma-a long-term follow-up single center experience

Autologous stem cell transplantation (autoSCT) can achieve long-term remission in primary refractory or relapsed Hodgkin lymphoma (r/r HL); however, still up to 50% of patients relapse after autoSCT. In this retrospective analysis, we investigated the impact of autologous stem cell transplantation in a consecutive, unselected cohort of primary refractory and relapsed Hodgkin lymphoma patients (n = 66) with the majority of patients treated in the pre-brentuximab vedotin and immune checkpoint inhibitor era. In our cohort, a 5-year overall survival (OS) from autoSCT of 59.5% and a 5-year progression-free survival (PFS) after autoSCT of 46.1% was achieved. Multivariate analysis revealed primary refractory disease and early relapse (< 12 months) after initial therapy as well as the presence of B symptoms at relapse as independent risk factors associated with a higher risk for relapse and an inferior PFS and OS. Several other clinical factors, including the presence of extranodal disease at relapse and failure to achieve a complete response to salvage chemotherapy, were associated with a trend towards an inferior survival. Patients relapsing after autoSCT had a particularly poor outcome, regardless of eligibility to undergo allogeneic stem cell transplantation (alloSCT). We further evaluated recently published prognostic models for r/r HL patients undergoing autoSCT and could validate several risk scores in our independent "real world" cohort.

ESMO Consensus Conference on malignant lymphoma: management of 'ultra-high-risk' patients

The European Society for Medical Oncology (ESMO) consensus conference on malignant lymphoma was held on 20 June 2015 in Lugano, Switzerland, and included a multidisciplinary panel of 25 leading experts. The aim of the conference was to develop recommendations on critical subjects difficult to consider in detail in the ESMO Clinical Practice Guidelines. The following areas were identified: (1) the elderly patient, (2) prognostic factors suitable for clinical use and (3) the 'ultra-high-risk' group. Before the conference, the expert panel was divided into three working groups; each group focused on one of these areas in order to address clinically relevant questions relating to that topic. All relevant scientific literature, as identified by the experts, was reviewed in advance. During the consensus conference, each working group developed recommendations to address each of the questions devised by their group. These recommendations were then presented to the entire multidisciplinary panel and a consensus was reached. This manuscript presents recommendations regarding the management of the following 'ultra-high-risk' situations: (1) early central nervous system relapse of diffuse large B-cell lymphoma, (2) primary refractory Hodgkin lymphoma and (3) plasmablastic lymphoma. Results, including a summary of evidence supporting each recommendation, are detailed in this manuscript. All expert panel members approved this final article.

Allogeneic stem cell transplantation improves survival in relapsed Hodgkin lymphoma patients achieving complete remission after salvage treatment

Allogeneic stem cell transplant (alloSCT) is a current treatment option for patients with refractory/relapsed classic Hodgkin lymphoma (CHL), including those who have failed an autologous transplantation. We performed a retrospective multicenter analysis of 113 patients (median age 28 years; range 14-56; 54% males) with refractory/relapsed (R/R) CHL who had undergone alloSCT in Argentina. Kaplan-Meier was used to estimate overall (OS) and progression-free survival (PFS). Relapse rate (RR) and non-relapse mortality (NRM) were estimated with cumulative incidence analysis. Disease status at transplant was complete remission (CR) in 39%, partial remission (PR) in 44%, and stable/progressed disease (S/PD) in 17% of the patients. Donor type was matched related (MRD) in 60%, unrelated (URD) in 19%, and haploidentical (HID) in 21% of the patients. OS and PFS at 2 years were 43% and 27%, respectively, for all the cohort. In the univariate analysis, patients in CR showed better OS (p ≤ 0.001) and PFS (p ≤ 0.001), and lower NRM (p = 0.04). HID had better PFS (p = 0.04) and lower RR (p = 0.02). In the multivariate analysis, CR showed a significant impact on OS and PFS, and HID on PFS. AlloSCT is a feasible procedure in patients with CHL. Those in CR at the time of the transplant had better outcomes. Haploidentical transplantation is associated with better PFS in these patients with poor prognosis.

Allogeneic transplantation for relapsed and refractory Hodgkin lymphoma: long-term outcomes and graft-versus-host disease-free/relapse-free survival

This monocentric retrospective study included 70 consecutive relapsed/refractory Hodgkin lymphoma (RR-HL) patients receiving reduced-intensity allogeneic stem cell transplantation (alloSCT). We evaluated overall and progression-free survival (OS, PFS), graft-versus host disease/relapse-free survival (GFRS), and chronic GVHD-free OS (cGVHD-free OS) defined as OS without moderate-to-severe cGVHD. Patients had a median age of 33 years (range, 18-60 years), 23% had refractory disease (SD/PD). Donors were HLA identical (39%), unrelated (30%), or haploidentical (31%). Median follow-up was 6.2 years. Five-year OS was 59% and PFS was 49%. NRM was 16% at 1 year. 44% of patients had cGVHD, and 14% moderate-to-severe cGVHD at last follow-up. GFRS and cGVHD-free OS were 26 and 48% at 5 years. In multivariate analysis, resistant disease at alloSCT impacted survival and GFRS. In conclusion, disease response before alloSCT impacts survival and GFRS. GVHD outcomes may help comparing the long-term effects of the new salvage treatments that bridge patients to alloSCT.

Tandem Autologous Hematopoietic Cell Transplantation for Patients with Primary Progressive or Recurrent Hodgkin Lymphoma: A SWOG and Blood and Marrow Transplant Clinical Trials Network Phase II Trial (SWOG S0410/BMT CTN 0703)

Based on promising pilot data a phase II tandem autologous hematopoietic stem cell transplant (AHSCT) trial for relapsed/refractory Hodgkin lymphoma (HL) was performed in the US intergroup setting to determine if long-term progression-free survival (PFS) could be improved. Patients were enrolled after salvage therapy and stem cell collection. Sensitivity to salvage was defined by 1999 Standardized Response Criteria and did not include fluorodeoxyglucose-positron emission tomography. Cycle 1 consisted of melphalan 150 mg/m² with half of the stem cells. For stable disease or better, patients received cycle 2 consisting of single doses of etoposide 60 mg/kg and cyclophosphamide 100 mg/kg and either total body radiation 12 Gy in 8 fractions over 4 days or BCNU 150 mg/m²/day for 3 days with the remaining stem cells. Of 98 enrolled patients, 89 were eligible and treated: 82 completed both cycles of AHSCT, 47 (53%) had primary refractory HL, and 72 (81%) were resistant to salvage therapy. There were no treatment-related deaths in the first year after AHSCT. With a median follow-up of 6.2 years (range, 2 to 7.7) for eligible patients who remained alive, the 2-year and 5-year PFS were 63% (95% CI, 52% to 72%) and 55% (95% CI, 44% to 64%) respectively; the 2-year and 5-year overall survival were 91% (95% CI, 83% to 95%) and 84% (95% CI, 74% to 90%), respectively. Univariate Cox regression analysis showed Zubrod performance status and lactate dehydrogenase levels > 1 times upper limit of normal at the time of enrollment were significantly associated with PFS. The observed 5-year PFS of 55% suggests the tandem approach appears to be effective in treating HL patients demonstrated to have poor prognosis in prior single AHSCT trials. This trial was registered at www.clinicaltrials.gov as NCT00233987.

How to Approach a Hodgkin Lymphoma Patient With Relapse After Autologous SCT: Allogeneic SCT

Hodgkin lymphoma (HL) is a highly curable B-cell lymphoma, and ∼90% of patients who present with early-stage (stage I-II) disease and 70% of patients who present with late-stage disease will be cured with standard frontline treatment. For patients with relapsed or refractory (r/r) disease after initial therapy, the standard of care is salvage chemotherapy, followed by autologous transplantation (autoSCT). Although this approach will cure a significant proportion of patients, upto 50% of patients will experience disease progression after autoSCT, and this population has historically had a very poor prognosis. In the past, further salvage chemotherapy, followed by allogeneic transplantation (alloSCT), has been the only option associated with a significant probability of long-term survival, owing to a graft-versus-lymphoma effect. However, this approach has been complicated by high rates of treatment-related morbidity and mortality and a high risk of disease relapse. Furthermore, many patients have been unable to proceed to alloSCT because of disease refractoriness, poor performance status, or the lack of a donor. However, significant therapeutic advances in recent years have greatly expanded the options for patients with post-autoSCT r/r HL. These include the anti-CD30 antibody-drug conjugate brentuximab vedotin and the checkpoint inhibitors nivolumab and pembrolizumab, as well as increasing experience with alternative donor alloSCT, especially from haploidentical donors. In the present review, we discuss the current role of alloSCT in the treatment of HL after autoSCT relapse.

[Preventative and therapeutic relapse strategies after allogeneic hematopoietic stem cell transplantation: Guidelines from the Francophone society of bone marrow transplantation and cellular therapy (SFGM-TC)]

Disease relapse remains the first cause of mortality of hematological malignancies after allogeneic hematopoietic stem cell transplantation (allo-HCT). The risk of recurrence is elevated in patients with high-risk cytogenetic or molecular abnormalities, as well as when allo-HCT is performed in patients with refractory disease or with persistent molecular or radiological (PET-CT scan) residual disease. Within the frame of the 7th annual workshops of the francophone society for bone marrow transplantation and cellular therapy, the working group reviewed the literature in order to elaborate unified guidelines for the prevention and treatment of relapse after allo-HCT. For high risk AML and MDS, a post transplant maintenance strategy is possible, using hypomethylating agents or TKI anti-FLT3 when the target is present. For Philadelphia positive ALL, there was a consensus for the use of post-transplant TKI maintenance. For lymphomas, there are no strong data on the use of post-transplant maintenance, and hence a preemptive strategy is recommended based on modulation of immunosuppression, close follow-up of donor chimerism, and donor lymphocytes infusion. For multiple myeloma, even though the indication of allo-HCT is controversial, our recommendation is post transplant maintenance using bortezomib, due to its a good toxicity profile without increasing the risk of GVHD.

Post-Transplantation Cyclophosphamide-Based Haploidentical Transplantation as Alternative to Matched Sibling or Unrelated Donor Transplantation for Hodgkin Lymphoma: A Registry Study of the Lymphoma Working Party of the European Society for Blood and Marrow Transplantation

Purpose

To compare the outcome of patients with Hodgkin lymphoma who received post-transplantation cyclophosphamide–based haploidentical (HAPLO) allogeneic hematopoietic cell transplantation with the outcome of patients who received conventional HLA-matched sibling donor (SIB) and HLA-matched unrelated donor (MUD).

Patients and Methods

We retrospectively evaluated 709 adult patients with Hodgkin lymphoma who were registered in the European Society for Blood and Marrow Transplantation database who received HAPLO (n = 98), SIB (n = 338), or MUD (n = 273) transplantation.

Results

Median follow-up of survivors was 29 months. No differences were observed between groups in the incidence of acute graft-versus-host disease (GVHD). HAPLO was associated with a lower risk of chronic GVHD (26%) compared with MUD (41%; P = .04). Cumulative incidence of nonrelapse mortality at 1 year was 17%, 13%, and 21% in HAPLO, SIB, and MUD, respectively, and corresponding 2-year cumulative incidence of relapse or progression was 39%, 49%, and 32%, respectively. On multivariable analysis, relative to SIB, nonrelapse mortality was similar in HAPLO ( P = .26) and higher in MUD ( P = .003), and risk of relapse was lower in both HAPLO ( P = .047) and MUD ( P < .001). Two-year overall survival and progression-free survival were 67% and 43% for HAPLO, 71% and 38% for SIB, and 62% and 45% for MUD, respectively. There were no significant differences in overall survival or progression-free survival between HAPLO and SIB or MUD. The rate of the composite end point of extensive chronic GVHD and relapse-free survival was significantly better for HAPLO (40%) compared with SIB (28%; P = .049) and similar to MUD (38%; P = .59).

Conclusion

Post-transplantation cyclophosphamide–based HAPLO transplantation results in similar survival outcomes compared with SIB and MUD, which confirms its suitability when no conventional donor is available. Our results also suggest that HAPLO results in a lower risk of chronic GVHD than MUD transplantation.

Advances in the pathophysiology and treatment of relapsed/refractory Hodgkin's lymphoma with an emphasis on targeted therapies and transplantation strategies

Hodgkin’s lymphoma (HL) is highly curable with first-line therapy. However, a minority of patients present with refractory disease or experience relapse after completion of frontline treatment. These patients are treated with salvage chemotherapy followed by autologous stem cell transplantation (ASCT), which remains the standard of care with curative potential for refractory or relapsed HL. Nevertheless, a significant percentage of such patients will progress after ASCT, and allogeneic hematopoietic stem cell transplantation remains the only curative approach in that setting. Recent advances in the pathophysiology of refractory or relapsed HL have provided the rationale for the development of novel targeted therapies with potent anti-HL activity and favorable toxicity profile, in contrast to cytotoxic chemotherapy. Brentuximab vedotin and programmed cell death-1-based immunotherapy have proven efficacy in the management of refractory or relapsed HL, whereas several other agents have shown promise in early clinical trials. Several of these agents are being incorporated with transplantation strategies in order to improve the outcomes of refractory or relapsed HL. In this review we summarize the current knowledge regarding the mechanisms responsible for the development of refractory/relapsed HL and the outcomes with current treatment strategies, with an emphasis on targeted therapies and hematopoietic stem cell transplantation.

Relapse of Hodgkin lymphoma after autologous transplantation: Time to rethink treatment?

Relapse of Hodgkin lymphoma after autologous hematopoietic cell transplantation (autologous HCT) is a major therapeutic challenge. Its management, at least in younger patients, traditionally involves salvage chemotherapy aiming to achieve disease remission followed by consolidation with allogeneic hematopoietic cell transplantation (allogeneic HCT) in eligible patients. The efficacy of salvage therapy is variable and newer combination chemotherapy regimens have improved the outcomes. Factors such as shorter time to relapse after autologous HCT and poor performance status have been identified as predictors of poor outcome. Newer agents such as immunoconjugate brentuximab vedotin, checkpoint inhibitors (e.g., pembrolizumab, nivolumab), lenalidomide, and everolimus are available for the treatment of patients relapsing after autologous HCT. With the availability of reduced intensity conditioning allogeneic HCT, more patients are eligible for this therapy with lesser toxicity and better efficacy due to graft versus lymphoma effects. Alternative donor sources such as haploidentical stem cell transplantation and umbilical cord blood transplantation are expanding this procedure to patients without HLA-matched donors. However, strategies aimed at reduction of disease relapse after reduced intensity conditioning allogeneic HCT are needed to improve the outcomes of this treatment. This review summarizes the current data on salvage chemotherapy and HCT strategies used to treat patients with relapsed Hodgkin lymphoma after prior autologous HCT.

Improving outcomes after allogeneic hematopoietic cell transplantation for Hodgkin lymphoma in the brentuximab vedotin era

Allogeneic hematopoietic cell transplantation (allo HCT) remains a valuable alternative for relapsed/refractory (R/R) Hodgkin lymphoma (HL). Data on allo HCT outcomes in the era of new HL therapies are needed. We evaluated 72 R/R HL patients who received reduced intensity conditioning (RIC) allo HCT and compared the time periods 2009-2013 (n=20) to 2000-2008 (n=52). Grafts included HLA-matched sibling (35%), unrelated donor (8%) and umbilical cord blood (UCB, 56%). In recent period, patients more often received brentuximab vedotin (BV, 60% vs 2%), had fewer comorbidities (Sorror index 0: 60% vs 12%) and were in complete remission (50% vs 23%). Median follow-up was 4.4 years. Three-year progression-free survival (PFS) improved for patients treated between 2009-2013 (49%, 95% CI 26-68%) as compared to the earlier era (23%, 95% CI 13-35%, p=0.02). Overall survival (OS) at 3-years was 84% (95% CI 57-94%) vs 50% (95% CI 36-62%, p=0.01), reflecting lower non-relapse mortality and relapse rates. In multivariate analysis mortality was higher among those with chemoresistance (HR 3.83, 95% CI 1.38-10.57), while treatment during the recent era was associated with better OS (HR for period 2009-2013: 0.24, 95% CI 0.07-0.79) and PFS (HR 0.46, 95% CI 0.23-0.92). Allo HCT in patients with R/R HL is now a more effective treatment.

Reduced-intensity and non-myeloablative allogeneic stem cell transplantation from alternative HLA-mismatched donors for Hodgkin lymphoma: a study by the French Society of Bone Marrow Transplantation and Cellular Therapy

Allogeneic stem cell transplantation (allo-SCT) following a non-myeloablative (NMA) or reduced-intensity conditioning (RIC) is considered a valid approach to treat patients with refractory/relapsed Hodgkin lymphoma (HL). When an HLA-matched donor is lacking a graft from a familial haploidentical (HAPLO) donor, a mismatched unrelated donor (MMUD) or cord blood (CB) might be considered. In this retrospective study, we compared the outcome of patients with HL undergoing a RIC or NMA allo-SCT from HAPLO, MMUD or CB. Ninety-eight patients were included. Median follow-up was 31 months for the whole cohort. All patients in the HAPLO group (N=34) received a T-cell replete allo-SCT after a NMA (FLU-CY-TBI, N=31, 91%) or a RIC (N=3, 9%) followed by post-transplant cyclophosphamide. After adjustment for significant covariates, MMUD and CB were associated with significantly lower GvHD-free relapse-free survival (GRFS; hazard ratio (HR)=2.02, P=0.03 and HR=2.43, P=0.009, respectively) compared with HAPLO donors. In conclusion, higher GRFS was observed in Hodgkin lymphoma patients receiving a RIC or NMA allo-SCT with post-transplant cyclophosphamide from HAPLO donors. Our findings suggest they should be favoured over MMUD and CB in this setting.

Gemcitabine, Fludarabine, and Melphalan for Reduced-Intensity Conditioning and Allogeneic Stem Cell Transplantation for Relapsed and Refractory Hodgkin Lymphoma

Forty patients (median age, 31 years; range, 20 to 63) with Hodgkin lymphoma underwent an allogeneic stem cell transplant with the gemcitabine-fludarabine-melphalan reduced-intensity conditioning regimen. Thirty-one patients (77%) had undergone a prior autologous stem cell transplant, with a median time to progression after transplant of 6 months (range, 1 to 68). Disease status at transplant was complete remission/complete remission, undetermined (n = 23; 57%), partial remission (n = 14; 35%), and other (n = 3; 8%). Twenty-six patients (65%) received brentuximab vedotin before allotransplant. The overall complete response rate before allotransplant was 65% in brentuximab-treated patients versus 42% in brentuximab-naive patients (P = .15). At the latest follow-up (October 2015) 31 patients were alive. The median follow-up was 41 months (range, 5 to 87). Transplant-related mortality rate at 3 years was 17%. Pulmonary, skin toxicities, and nausea were seen in 13 (33%), 11 (28%), and 37 (93%) patients, respectively. At 3 years, estimates for overall and progression-free survival were 75% (95% CI, 57% to 86%) and 54% (95% CI, 36% to 70%). Overall incidence for disease progression was 28% (95% CI, 16% to 50%). We believe the gemcitabine-fludarabine-melphalan regimen allows moderate dose intensification with acceptable morbidity and mortality. The inclusion of gemcitabine affected nausea, pulmonary, and likely skin toxicity. Exposure to brentuximab vedotin allowed more patients to reach allogeneic stem cell transplantation in complete remission. With over 50% of patients progression-free at 3 years, allogeneic stem cell transplantation with reduced-intensity conditioning remains an effective and relevant treatment option for Hodgkin lymphoma in the brentuximab vedotin era.

Donor lymphocyte infusion after allogeneic stem cell transplantation

Allogeneic stem cell transplantation (allo-SCT) is considered the cornerstone in the treatment of several malignant and not malignant hematological diseases. However, relapse of hematological disease after allo-SCT is considered the most challenging point in the field. The risk can be reduced through optimal patients, donor and disease selection before allo-SCT, but harnessing donor immune system is an appealing way to treat or avoid disease relapse. Donor lymphocyte infusion (DLI) is a simple and effective therapy after allo-SCT. In this paper, the efficacy of DLI will be analyzed in different hematological diseases, focusing also on their therapeutic or pre-emptive use.

Impact of Pretransplantation (18)F-Fluorodeoxyglucose-Positron Emission Tomography on Survival Outcomes after T Cell-Depleted Allogeneic Transplantation for Hodgkin Lymphoma

Pretransplant (18)F-fluorodeoxyglucose (FDG) positron emission tomography status is an important prognostic factor for outcomes after autologous stem cell transplantation (SCT) in Hodgkin lymphoma (HL), but its impact on outcomes after allogeneic SCT remains unclear. We retrospectively evaluated outcomes after T cell-depleted allogeneic SCT of 116 patients with nonprogressive HL according to pretransplant Deauville scores. Endpoints were overall survival (OS), progression-free survival (PFS), relapse rate (RR), and nonrelapse-related mortality (NRM). OS, PFS, and RR did not differ significantly between the Deauville 1 to 2 and Deauville 3 to 5 cohorts (OS: 77.5% versus 67.3%, P = .49; PFS: 59.4% versus 55.7%, P = .43; RR: 20.9% versus 22.6%, P = .28 at 4 years). Differences in PFS remained statistically nonsignificant when comparisons were made between Deauville 1 to 3 and Deauville 4 to 5 cohorts (60.9% versus 51.4%, P = .10), and RR remained very similar (21.5% versus 23.8%, P = .42). Multivariate analyses demonstrated trends toward significance for an effect of Deauville score on PFS (hazard ratio 1.82 for Deauville 4 to 5, P = .06) and for number of lines of prior therapy on OS (hazard ratio 2.34 for >5 lines, P = .10). The latter effect appeared to be driven by higher NRM rather than increased RR. Our findings suggest that Deauville score before allogeneic SCT in patients with nonprogressive HL has a relatively modest impact on survival outcomes in comparison with the impact in autologous SCT and that predictive values for the individual patient remain low, indicating that residual FDG-avid disease should not preclude allogeneic SCT. Furthermore, our findings bring into question the importance of attainment of metabolic complete response in this setting if it is at the expense of increasing NRM risk.

Alemtuzumab-BEAM as conditioning for allogeneic hematopoietic stem cell transplantation in relapsed/refractory Hodgkin lymphoma: a single-center analysis

Purpose

Treatment of refractory Hodgkin disease deserves specific considerations. Recently, alemtuzumab-BEAM has been introduced in allogeneic hematopoietic stem cell transplantation (HSCT) in these patients.

Methods

We retrospectively analyzed the outcome of 20 patients with relapsed/refractory Hodgkin’s lymphoma (HL) who received allogeneic HSCT following conditioning therapy with alemtuzumab-BEAM.

Results

Treatment-related toxicity was tolerable. Half of the patients (50 %) had infections. Of these, 50 % were found to have pneumonia or catheter-related infections. In 20 %, an oral mucositis was observed. Acute graft-versus-host disease (GvHD) (≥grade 2) was seen in three patients. Complete remission (CR) could be achieved in 17 patients (85 %), 2 patients had persistent Hodgkin disease, and 1 patient died from infection prior to CR evaluation. Median progression-free survival and overall survival were 17.9 and 67.5 months, respectively. From the 17 CR patients, 8 had a relapse after a median of 10 months. Notably, of the eight patients relapsing after HSCT, all patients received another salvage treatment and four patients are still alive, whereas the other four patients died due to further progress. Six out of the remaining nine patients are still in CR, whereas the other three died from chronic GvHD and multi-organ failure. Overall, seven patients experienced chronic GvHD.

Conclusion

In summary, alemtuzumab-BEAM is a well-tolerated conditioning therapy for allogeneic HSCT with high response rates in refractory HL.

Allogeneic hematopoietic stem cell transplantation in Hodgkin lymphoma: a systematic review and meta-analysis

Allogeneic stem cell transplantation (allo-SCT) outcomes in patients with Hodgkin lymphoma (HL) remain poorly defined. We performed a meta-analysis of allo-SCT studies in HL patients. The primary endpoints were 6-month, 1-year, 2-year and 3-year relapse-free survival (RFS) and overall survival (OS). A total of 42 reports (1850 patients) was included. The pooled estimates (95% confidence interval) for 6-month, 1-year, 2-year and 3-year RFS were 77 (59-91)%, 50 (42-57)%, 37 (31-43)% and 31 (25-37)%, respectively. The corresponding numbers for OS were 83 (75-91)%, 68 (62-74)%, 58 (52-64)% and 50 (41-58)%, respectively. There was statistical heterogeneity among studies in all outcomes. In meta-regression, accrual initiation year in 2000 or later was associated with higher 6-month (P=0.012) and 1-year OS (P=0.046), and pre-SCT remission with higher 2-year OS (P=0.047) and 1-year RFS (P=0.016). In conclusion, outcomes of allo-SCT in HL have improved over time, with 5-10% lower non-relapse mortality and relapse rates, and 15-20% higher RFS and OS in studies that initiated accrual in 2000 or later compared with earlier studies. However, there is no apparent survival plateau, demonstrating the need to improve on current allo-SCT strategies in relapsed/refractory HL.

Double umbilical cord blood transplant is effective therapy for relapsed or refractory Hodgkin lymphoma

A sub-group of patients with Hodgkin Lymphoma (HL) who relapse after autologous stem cell transplant can achieve long-term disease-free-survival after allogeneic stem cell transplant (alloSCT). There is limited information regarding the tolerability and efficacy of double umbilical cord blood transplant (dUCBT) for relapsed/refractory HL. We analyzed 27 consecutive, heavily pre-treated patients receiving dUCBT for relapsed/refractory HL at two centers from 2003-2014. The majority of patients relapsed <6 months after autologous stem cell transplant. A total of 15 patients received myeloablative (most commonly melphalan, fludarabine, thiotepa and anti-thymocyte globulin [ATG]) and 12 non-myeloablative conditioning regimens (fludarabine, cyclophosphamide, 200cGy total body irradiation +/- ATG). All patients engrafted; median time to neutrophil and platelet engraftment was 17 and 37 days, respectively. Overall response rate was 68%; 58% achieved complete remission. Median progression-free survival (PFS) was 12.2 months; median overall survival was 27 months. Cumulative incidences of relapse and of non-relapse mortality at 5 years were 30% and 37.9%, respectively; 5-year PFS was 31.3% (95%CI 10.1-52.5). There was a trend toward inferior PFS in patients with lymph node size ≥2 cm at the time of alloSCT (p = 0.07) and toward inferior survival in patients with chemorefractory disease pre-alloSCT (p = 0.12). dUCBT is feasible in patients with heavily pre-treated HL and can achieve long-term disease-free survival in approximately 30% of patients.

Salvage treatment for relapsed/refractory Hodgkin lymphoma: role of allografting, brentuximab vedotin and newer agents

INTRODUCTION

Second-line, salvage chemotherapy followed by high-dose chemotherapy and autologous stem cell transplantation (AUTO-SCT) is the standard of care for patients with relapsed/refractory (R/R) Hodgkin lymphoma (HL). Approximately 50% of patients relapse after AUTO-SCT and their prognosis is generally poor. Brentuximab Vedotin (BV) has demonstrated efficacy in this setting and allogeneic (ALLO)-SCT represents an option with curative potential in this subgroup of patients.

AREAS COVERED

A systematic review has been conducted to explore the actual knowledge on ALLO-SCT, BV and newer agents in R/R HL.

EXPERT OPINION

The introduction of BV in clinical practice has significantly improved the management of post-AUTO-SCT relapses and the drug can induce durable remissions in a subset of R/R HL. Allografting select patients has been used to improve clinical outcomes and recent case series have begun to explore BV as a potential 'bridge' to allo-SCT, even though the optimal timing of ALLO-SCT after BV response remains undetermined. However, reduced tumor burden at the time of ALLO-SCT is a key factor to decrease relapse risk. Based on the unique composition of the tumor, more recently new agents such as PD-1 inhibitors have been developed. The potential role of PD-1 inhibitors with ALLO-SCT remains to be explored.

Pushing the envelope-nonmyeloablative and reduced intensity preparative regimens for allogeneic hematopoietic transplantation

Allogeneic hematopoietic cell transplantation (HCT) was originally developed to allow delivery of myeloablative doses of chemotherapy and radiotherapy. With better understanding of disease pathophysiology, the graft vs malignancy (GVM) effect of allogeneic hematopoietic transplantation and toxicities associated with myeloablative conditioning (MAC) regimens, the focus shifted to developing less toxic conditioning regimens to reduce treatment-related morbidity without compromising survival. Although HCT with MAC is preferred to reduced intensity conditioning (RIC) for most patients ⩽60 years with AML/myelodysplastic syndrome and ALL, RIC and nonmyeloablative (NMA) regimens allow HCT for many otherwise ineligible patients. Reduced intensity preparative regimens have produced high rates of PFS for diagnoses, which are highly sensitive to GVM. Relapse of the malignancy is the major cause of treatment failure with RIC/NMA HCT. Incorporation of novel agents like bortezomib or lenalidomide, addition of cellular immunotherapy and use of targeted radiation therapies could further improve outcome. In this review, we discuss commonly used RIC/NMA regimens and promising novel regimens.

Umbilical cord blood transplantation in adults with advanced hodgkin's disease: high incidence of post-transplant lymphoproliferative disease

We report the outcome of 30 consecutive patients with Hodgkin disease (HD) who underwent single-unit UCBT. Most (90%) patients had failed previous autologous hematopoietic stem cell transplantation. The conditioning regimens were based on combinations of thiotepa, busulfan, cyclophosphamide or fludarabine, and antithymocyte globulin. The cumulative incidence (CI) of myeloid engraftment was 90% [95% confidence interval (C.I.), 74-98%] with a median of 18 d (range, 10-48). CI of acute graft-versus-host disease (GvHD) grades II-IV was 30% (95% C.I., 17-44%), while the incidence of chronic GVHD was 42% (95% C.I., 23-77%). The non-relapse mortality (NRM) at 100 d and 4 yr was 30% (95% C.I., 13-46%) and 47% (95% C.I., 29-65%), respectively. EBV-related post-transplant lymphoproliferative disease (EBV-PTLD) accounted for more than one-third of transplant-related death, with an estimate incidence of 26% (95% C.I., 9-44). The incidence of relapse at 4 yr was 25% (95% C.I., 9-42%). Four-year event-free survival (EFS) and overall survival (OS) were 28% and 30%, respectively. Despite a high NRM and an unexpected high incidence of EBV-PTLD, UCBT in heavily pretreated HD patients is an option for patients lacking a suitable adult donor, provided the disease is not in refractory relapse.

Role of cytotoxic therapy with hematopoietic cell transplantation in the treatment of Hodgkin lymphoma: guidelines from the American Society for Blood and Marrow Transplantation

The role of hematopoietic cell transplantation (HCT) in the therapy of Hodgkin lymphoma (HL) in pediatric and adult patients is reviewed and critically evaluated in this systematic evidence-based review. Specific criteria were used for searching the published literature and for grading the quality and strength of the evidence and the strength of the treatment recommendations. Treatment recommendations based on the evidence are included and were reached unanimously by a panel of HL experts. Both autologous and allogeneic HCT offer a survival benefit in selected patients with advanced or relapsed HL and are currently part of standard clinical care. Relapse remains a significant cause of failure after both transplant approaches, and strategies to decrease the risk of relapse remain an important area of investigation.

Current role of autologous and allogeneic stem cell transplantation for relapsed and refractory hodgkin lymphoma

Classical Hodgkin lymphoma (cHL) is a relatively rare disease, with approximately 9,200 estimated new cases and 1,200 estimated deaths per year in the United States. First-line chemo-radiotherapy leads to cure rates approaching 80% in patients with advanced-stage disease. However, 25 to 30% of these patients are not cured with chemotherapy alone (i.e., the ABVD regimen) and show either primary refractoriness to chemotherapy, early disease relapse or late disease relapse. Second-line salvage high-dose chemotherapy (HDC) and autologous stem cell transplantation (SCT) have an established role in the management of refractory/relapsed cHL, leading to durable responses in approximately 50% of relapsed patients and a minority of refractory patients. However, due to the poor responses to second-line salvage chemotherapy and dismal long-term disease control of primary refractory and early relapsed patients, their treatment represents an unmet medical need. Allogeneic SCT represents, by far, the only strategy with a curative potential for these patients; however, as discussed in this review, it’s role in cHL remains controversial. Despite a general consensus that early relapsed and primary refractory patients represent a clinical challenge requiring effective treatments to achieve long-term disease control, there has been no consensus on the optimal therapy that should be offered to these patients. This review will briefly discuss the clinical results and the main issues regarding autologous SCT as well as the current role of allogeneic SCT.

Brentuximab vedotin in patients with Hodgkin lymphoma and a failed allogeneic stem cell transplantation: results from a named patient program at four Italian centers

BACKGROUND

Brentuximab vedotin (BV) has demonstrated an extraordinary efficacy in heavily pretreated classical Hodgkin lymphoma (cHL) patients, targeting CD30-positive cells; however, limited data have been reported on the efficacy of BV in cHL patients failing allogeneic stem cell transplantation (allo-SCT). The aim of this study was to retrospectively evaluate the efficacy and safety of BV in a multicenter setting of cHL relapsing or progressing after allo-SCT.

METHODS

Sixteen BV-naïve patients with recurrent cHL after allo-SCT were included in a compassionate use program and treated with intravenous BV at the dose of 1.8 mg/kg of body weight every 3 weeks for a maximum of 16 cycles.

RESULTS

The objective response rate was 69%. Five patients (31%) had complete remission, and 6 (37%) had partial remission. Stable disease was observed in 4 patients (25%), and progressive disease was observed in 1 (6%). After median follow-up of 26 months (range: 5-30 months), median progression-free survival (PFS), overall survival (OS), and duration of response were 7, 25, and 5 months, respectively. The 2-year PFS and OS were 20% and 61%, respectively. Grade 3-4 hematological adverse events included anemia (15%), thrombocytopenia (12%), and neutropenia (18%). Grade 3 peripheral sensory neuropathy occurred in 2 patients (12%).

CONCLUSION

BV therapy is an effective and safe approach for achieving transient disease control in cHL patients with failed allo-SCT. To improve disease control, future studies should explore the combination of BV with targeted agents.

Brentuximab vedotin compared with other therapies in relapsed/refractory Hodgkin lymphoma post autologous stem cell transplant: median overall survival meta-analysis

OBJECTIVE

This meta-analysis compared the median overall survival (mOS) of brentuximab vedotin reported in the pivotal phase 2 study with published results of other therapies for the treatment of relapsed/refractory (R/R) Hodgkin lymphoma (HL) post autologous stem cell transplant (ASCT).

RESEARCH DESIGN AND METHODS

A systematic literature review identified studies that reported survival outcomes following conventional/experimental therapies in R/R HL patients, with ≥50% having failed ≥1 ASCT. Kaplan-Meier curves were used to reconstruct individual patient level survival data. Patients were grouped by treatment type and reconstructed data were used to estimate the mOS. Censored median regression modeling was used to compare mOS in each group with the mOS in the pivotal brentuximab vedotin trial. All patients in the pivotal trial had undergone ASCT, therefore a sensitivity analysis was conducted among studies with a 100% post-ASCT patient population.

RESULTS

The mOS reported for brentuximab vedotin was 40.5 (95% CI 30.8-NA) compared with 26.4 months (95% CI 23.5-28.5) across all 40 studies identified (n = 2518 excluding the brentuximab vedotin trial) (p < 0.0001). The difference in mOS between brentuximab vedotin and chemotherapy, allogeneic stem cell transplant (allo-SCT), and other therapies, was 17.7 (95% CI 10.6-24.7; p < 0.0001), 12.5 (95% CI 8.2-16.9; p < 0.0001), and 15.2 months (95% CI 4.9-25.5; p = 0.0037), respectively. For the 11 studies reporting a 100% prior-ASCT rate (n = 662 excluding the brentuximab vedotin trial), the mOS was 28.1 months (95% CI 23.9-34.5), and the difference in mOS between brentuximab vedotin, chemotherapy, allo-SCT, and other therapies was 19.0 (95% CI 12.9-25.1; p < 0.0001), 9.4 (p > 0.05), and 6.8 months (95% CI 1.2-12.5; p = 0.0018), respectively.

CONCLUSIONS

While some selection bias may occur when comparing trials with heterogeneous eligibility criteria, in the absence of randomized controlled trial data these results suggest brentuximab vedotin improves long-term survival and is associated with longer mOS in R/R HL post-ASCT compared with other therapies.

Durable remissions in a pivotal phase 2 study of brentuximab vedotin in relapsed or refractory Hodgkin lymphoma

We present response and survival outcomes of a pivotal phase 2 trial of the antibody-drug conjugate brentuximab vedotin in patients with relapsed/refractory Hodgkin lymphoma following autologous stem cell transplant (N = 102) after a median observation period of approximately 3 years. Median overall survival and progression-free survival were estimated at 40.5 months and 9.3 months, respectively. Improved outcomes were observed in patients who achieved a complete remission (CR) on brentuximab vedotin, with estimated 3-year overall survival and progression-free survival rates of 73% (95% confidence interval [CI]: 57%, 88%) and 58% (95% CI: 41%, 76%), respectively, in this group (medians not reached). Of the 34 patients who obtained CR, 16 (47%) remain progression-free after a median of 53.3 months (range, 29.0 to 56.2 months) of observation; 12 patients remain progression-free without a consolidative allogeneic stem cell transplant. Younger age, good performance status, and lower disease burden at baseline were characteristic of patients who achieved a CR and were favorable prognostic factors for overall survival. These results suggest that a significant proportion of patients who respond to brentuximab vedotin can achieve prolonged disease control. The trial was registered at www.clinicaltrials.gov as #NCT00848926.

Brentuximab vedotin is associated with improved progression-free survival after allogeneic transplantation for Hodgkin lymphoma

We previously reported that brentuximab vedotin (BV) enabled successful reduced-intensity allogeneic hematopoietic cell transplantation (RIC-alloHCT) in patients with relapsed Hodgkin lymphoma, after a median follow-up of 14.4 months. We now provide an updated report on 21 patients who were treated from 2009 to 2012 with BV before RIC-alloHCT with a uniform fludarabine/melphalan conditioning regimen and donor source after a median follow-up of 29.9 months. We have also retrospectively compared the patient characteristics and outcomes of these BV-pretreated patients to 23 patients who received fludarabine/melphalan RIC-alloHCT without prior BV, in the time period before the drug was available (2003 to 2009). Patients who were treated with BV before RIC-alloHCT had a lower median hematopoietic cell transplantation-specific comorbidity index and a reduced number of peri-transplantation toxicities. There were also improvements in 2-year progression-free survival (59.3% versus 26.1%) and cumulative incidence of relapse/progression (23.8% versus 56.5%).

Nonmyeloablative conditioning, unmanipulated haploidentical SCT and post-infusion CY for advanced lymphomas

Allo-SCT is regularly performed in advanced lymphoma. Haploidentical family donors are a valuable source of hematopoietic stem cells and transplants from these donors, using T-repleted grafts, has recently been successfully reported. We report on 49 patients with refractory lymphoma who received T-repleted haploidentical SCT with a non-myeloablative regimen and post-transplant CY. The median time to recover ANC >0.5 × 10e9/L and transfusion independent plt count >20 × 10e9/L was 20 days (range 14-38) and 26 days (range 14-395). The probability to reach ANC >0.5 × 10e9/L at 30 days was 87% and transfusion independent plt count >20 × 10e9/L at 100 days was 87%. The cumulative incidence of grade 2-4 acute GVHD (aGVHD) was 25.6% (95% confidence interval (CI): 12.9-38.3%) and the cumulative incidence of chronic GVHD (cGVHD) was 5.2% (95% CI: 0-12.4%). The median follow-up is 20.6 months (range 12-54), and the projected 2-year OS and PFS were 71 and 63%. The relapse rate was 18.7% (95% CI: 7.6-29.8%) and the median time to relapse was 4.4 months (range 1.1-8.3). At 2 years, cumulative incidence of NRM was 16.3% (95% CI: 5.9-26.8%). T-repleted Haploidentical transplantation with post-infusion CY is a feasible and effective therapy in the poor prognosis of advanced lymphoma patients.