Allogeneic Hematopoietic Cell Transplantation as Curative Therapy for Patients with Non-Hodgkin Lymphoma: Increasingly Successful Application to Older Patients

Long-term survival and clinical implications of allogeneic stem cell transplantation in relapse/refractory lymphoma: A 20-year Singapore experience

Introduction

Allogeneic haematopoietic stem cell transplantation (allo-HSCT) is a curative option for relapse/refractory (R/R) lymphomas that have failed autologous transplantation or for high-risk lymphomas in the upfront setting. We conducted a retrospective analysis on consecutive lymphoma patients who underwent allo-HSCT over a 20-year period (2003- 2022) at Singapore General Hospital and National University Hospital Singapore.

Method

A total of 121 patients were included in the study. Median age was 41 years. Diagnoses include Hodgkin lymphoma (HL, 15%), B-cell non- Hodgkin lymphoma (B-NHL, 34%), T-cell non-Hodgkin lymphoma (T-NHL, 31%) and natural killer T-cell lymphoma (NKTL, 20%). Moreover, 27% of patients had prior auto-haematopoietic stem cell transplanta-tion (auto-HSCT), and 84% received reduced intensity conditioning (RIC). Donor types were matched sibling donor (45%), matched unrelated donor (29%), haploidentical donor (19%) and cord blood (CB, 7%).

Results

After median follow-up of 56 months, estimated 4-year progression-free survival (PFS) and overall survival (OS) for all patients were 38% and 45%, respectively. Non-relapse mortality (NRM) was 15% at day 100 and 24% at 1 year. On univariate analysis, complete remission status at transplant and RIC confers superior OS. On multivariate analysis, HL was associated with superior OS compared to NHL, whereas matched unrelated donor transplant was associated with significantly inferior OS compared to matched sibling donor.

Conclusion

Long-term curative durability was observed with allo-HSCT for patients with relapsed/ refractory lymphomas. This real-world data serves as a valuable historical benchmark for future studies on lymphomas in Singapore and the Asia Pacific region.

High-Dose Chemotherapy and Autologous or Allogeneic Transplantation in Aggressive B-Cell Lymphoma-Is There Still a Role?

Novel therapies such as CAR-T, BTK inhibitors and PD-1 inhibitors have changed the management of aggressive B-cell lymphomas. Nonetheless, these novel therapies have their own risk of late toxicities including second malignancies. They also create a subgroup of patients with relapse, treatment failure, or indefinite maintenance. We discuss the current role of autologous and allogeneic stem cell transplantation in this context. In patients with recurrent diffuse large B-cell lymphoma, CAR-T cell treatment has largely replaced autologous transplant. Autologous transplant should be considered in patients with late relapses and in selected patients with T-cell-rich B-cell lymphoma, where CAR-T cell therapy may be less effective. It also remains the treatment of choice for consolidation of patients with primary CNS lymphoma. In mantle cell lymphoma, intensive chemotherapy combined with BTK inhibitors and rituximab results in excellent outcomes, and the role of autologous transplantation is declining. In Hodgkin's lymphoma, autologous transplant consolidation remains the standard of care for patients who failed initial chemotherapy. Allogeneic transplantation has lower relapse rates but more complications and higher non-relapse mortality than autologous transplantation. It is usually reserved for patients who fail autologous transplantation or in whom autologous stem cells cannot be collected. It may also have an important role in patients who fail CAR-T therapies. The increasing complexity of care and evolving sequencing of therapies for patients with aggressive B-cell lymphomas only emphasizes the importance of appropriate patient selection and optimal timing of stem cell transplantation.

PTCY-Based Haploidentical Donor Transplantation versus HLA-Matched Related and Unrelated Donor Transplantations in Patients with Refractory or Relapsed Lymphoma-A Matched-Pair Analysis

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) has demonstrated its potential as a curative option for patients with r/r lymphoma. With the introduction of post-transplant cyclophosphamide-based (PTCY) graft-versus-host disease (GvHD) prophylaxis, allo-HCT using haploidentical related donors (Haplo-HSCT) has emerged as a valuable alternative for patients without an available HLA-matched donor. In this study, we compared intermediate and long-term outcomes between Haplo-HSCT and HLA-matched related donor (MRD) and unrelated donor (URD) transplantations in 16 matched pairs using age, disease status, lymphoma classification and performance status as matching criteria. Of note, 88% of patients in each group presented with active disease at the time of conditioning. After a median follow-up of >10 years, 10-year overall and progression-free survival and non-relapse mortality incidence after Haplo-HSCT were 31%, 25% and 38%, respectively, and did not differ compared to the values observed in MRD-HSCT and URD-HSCT. A remarkable lower incidence of acute GvHD ≥ II and moderate and severe chronic GvHD was observed after Haplo-HSCT compared to MRD-HSCT (50%/50%, p = 0.03/0.03) and URD-HSCT (44%/38%, p = 0.04/0.08), resulting in slightly higher 10-year GvHD-free and relapse-free survival (25%) and chronic GvHD-free and relapse-free survival (25%) in the Haplo-HSCT group. In conclusion, Haplo-HSCT is an effective treatment in patients with non-remission NHL. Given its advantage of immediate availability, haploidentical donors should be preferably used in patients with progressive disease lacking an HLA-matched related donor.

The salvage role of allogeneic hematopoietic stem-cell transplantation in relapsed/refractory diffuse large B cell lymphoma

To clarify the role of allogeneic hematopoietic stem-cell transplantation (allo-HSCT) in the chimeric antigen receptor T-cell therapy era, we analyzed the clinical characteristics and outcomes of 52 patients treated with allo-HSCT with relapsed/refractory diffuse large B cell lymphoma. Most enrolled patients had previously undergone intensive treatments, the median number of chemotherapy lines was 4, and the median time from diagnosis to allo-HSCT was 27.1 months. Patients were divided into remission-achieved (n = 30) and active-disease (n = 22) groups before allo-HSCT. Over a median follow-up period of 38.3 months, overall survival (OS) and event-free survival (EFS) rates were 38.4% and 30.6%, respectively. The cumulative incidence of relapse (CIR) and the non-relapsed mortality (NRM) were 36.7% and 32.7%, respectively. OS, EFS, and graft-versus-host disease-free, relapse-free survival (GRFS) outcomes were significantly superior in the remission-achieved group with lower CIR. In a multivariate analysis, a shorter interval from diagnosis to allo-HSCT reflected relatively rapid disease progression and showed significantly poor OS and EFS with higher CIR. Patients with active disease had significantly lower EFS, GRFS, and higher CIR. Previous autologous stem-cell transplantation was associated with better GRFS. Allo-HSCT is an established modality with a prominent group of cured patients and still has a role in the CAR T-cell era, particularly given its acceptable clinical outcomes in young patients with chemo-susceptible disease.

Population-based real-world registry study to evaluate clinical outcomes of chronic graft-versus-host disease

INTRODUCTION

Chronic graft-versus-host disease (cGVHD) is a serious immune-mediated complication after allogeneic haematopoietic stem cell transplantation (HSCT), but in patients with malignancy, cGVHD development is associated with superior survival. Lack of reliable biomarkers and clinical underreporting means there is insufficient understanding of cGVHD clinical outcomes and balance between cGVHD treatment and maintaining beneficial graft-versus-tumour effects.

METHODS

We performed a Swedish population-wide registry study following patients who underwent allogeneic HSCT 2006-2015. cGVHD status was retrospectively classified using a real-world method based on the timing and extent of systemic immunosuppressive treatment.

RESULTS

cGVHD incidence among patients surviving ≥6 months post-HSCT (n = 1246) was 71.9%, significantly higher than previously reported. 5-year overall survival in patients surviving ≥6 months post-HSCT was 67.7%, 63.3%, and 65.3%, in non-, mild, and moderate-severe cGVHD, respectively. Non-cGVHD patients had a mortality risk almost five-fold higher compared to moderate-severe cGVHD patients 12-months post-HSCT. Moderate-severe cGVHD patients had greater healthcare utilization compared with mild and non cGVHD patients.

CONCLUSION

cGVHD incidence was high among HSCT survivors. Non-cGVHD patients had higher mortality during the first 6 months of follow-up; however, moderate-severe cGVHD patients had more comorbidities and healthcare utilization. This study highlights the urgent need for new treatments and real-time methods to monitor effective immunosuppression after HSCT.

Enhancement of effector functions of anti-CD20 monoclonal antibody by increased afucosylation in CHO cell line through cell culture medium optimization

Background

Recombinant therapeutic anti-CD20 monoclonal antibody (mAb) is used for the treatment of non-Hodgkin’s lymphoma, a common B cell lymphoma constituting 80% of all lymphomas. Anti-CD20 mAb contains an Fc-linked biantennary glycan. Although, anti-CD20 monoclonal antibodies are being increasingly used for immunotherapy, their efficacy is limited in a section of patients with drug resistance to immunotherapy. There is a need to improve the efficacy by increasing the effector functions, such as the antibody-dependent cellular cytotoxicity (ADCC) activity of anti-CD20 monoclonal antibodies.

Results

We developed a simple and cost-effective approach to enhance ADCC effector activity in an in-house developed clone of anti-CD20 monoclonal antibody by increasing afucosylation in a new clone of Chinese Hamster Ovary (CHO) cells using 8X uridine, manganese, and galactose (UMG) to modulate the osmolality of the medium. The purified anti-CD20 monoclonal antibody from 8X UMG-containing medium showed a 2-fold increase in afucose content and 203% ADCC activity in comparison to control antibody.

Conclusions

Our study reports enhanced ADCC activity by modulating afucosylation using osmolality by altering simple feed additives in the culture medium.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43141-022-00421-5.

Impact of donor types on reduced-intensity conditioning allogeneic stem cell transplant for mature lymphoid malignancies

We retrospectively compared the outcomes of reduced-intensity conditioning (RIC) transplantation from matched related donors (MRD; n = 266), matched unrelated donors (MUD; n = 277), and umbilical cord blood (UCB; n = 513) for mature lymphoid malignancies. The 3-year overall survival rates for the MRD, MUD, and UCB groups were 54%, 59%, and 40%, respectively (P < 0.001). Multivariate analysis showed no differences in survival between the MRD group and the MUD or UCB group. However, survival was significantly affected by the conditioning regimen and graft-versus-host disease (GVHD) prophylaxis in the UCB group, but not in the MRD and MUD groups. Notably, multivariate analysis showed that the risk of overall mortality in the UCB recipients who received the optimal conditioning regimen and GVHD prophylaxis (n = 116) was lower than that in the MRD group (relative risk [RR], 0.69; P = 0.03) and tended to be lower than that in the MUD group (RR, 0.75; P = 0.09). Our results suggest that UCB transplantation performed with the optimal conditioning regimen and GVHD prophylaxis is highly effective. Moreover, UCB is readily available. Thus, UCB transplantation with the optimal conditioning regimen and GVHD prophylaxis is preferable to MUD transplantation when MRD are not available in the setting of RIC transplantation for mature lymphoid malignancies.

CAR-T in B-Cell Lymphomas: The Past, Present, and Future

Aggressive B-cell lymphomas including diffuse large B-cell lymphoma make up the majority of non-Hodgkin's lymphoma globally. While more than half of these patients can be cured with modern chemoimmunotherapy regimens, the outcomes of relapsed or refractory disease continue to be very poor. Despite significant developments in targeted cancer therapies and immuno-oncology, the attainability of a cure remained an elusive goal outside of incorporating high doses of chemotherapy followed by hematopoietic stem cell transplantation, for patients who have chemosensitive disease. The development of chimeric antigen receptor T-cell therapy changed that paradigm and introduced a new field of therapeutic possibilities for these patients. In this review, we will discuss the current state of this therapeutic modality in B-cell lymphomas and provide opinions on where future efforts need to focus in order to further improve their clinical utility.

Advances in Immunotherapy for Diffuse Large B Cell Lymphoma

Diffuse large B cell lymphoma (DLBCL) is a heterogeneous disease that is normally treated with combination chemotherapy combined with the anti-CD20 monoclonal antibody rituximab. Although about two-thirds of patients are cured with initial chemo-immunotherapy, a sizable minority of patients will have relapsed or refractory (r/r) DLBCL. Standard therapy for r/r DLBCL is salvage chemotherapy followed by autologous stem cell transplantation (ASCT); however, a minority of patients have long-term remission with this approach. In recent years, there has been a proliferation of immunotherapies for the treatment of DLBCL that have expanded our treatment options for these patients, providing the opportunity for durable remissions that were not previously possible. In this review, we discuss these novel immunotherapies, including monoclonal antibodies, antibody-drug conjugates, bispecific antibodies and chimeric antigen receptor (CAR) T cells. The plethora of novel agents leaves patients with more therapeutic options, but leaves the practitioner faced with challenging decisions regarding the timing and indications for use of these immunotherapies. Although studies are ongoing, no agents have been verified as alternatives to standard salvage therapy followed by ASCT at first relapse. The opportunity for durable response and broad age range eligibility makes a strong case for CAR T cells to be used as third-line therapy. The remainder of the agents discussed can be useful in specific clinical scenarios including in patients who are not candidates for ASCT or CAR T cells, as bridging therapy to CAR T cells, or in the r/r setting after CAR T cell therapy failure.

Allogeneic stem cell transplantation as a curative option in relapse/refractory diffuse large B cell lymphoma: Spanish multicenter GETH/GELTAMO study

We performed a retrospective multicenter study including 140 patients with relapsed/refractory (R/R) diffuse large B cell lymphoma (DLBCL) who underwent allogeneic hematopoietic stem cell transplantation (allo-SCT) from March 1995 to November 2018. Our objective was to analyze long term outcomes. Seventy-four percent had received a previous auto-SCT (ASCT) and the median number of lines pre-allo-SCT was 3 (range 1-9). Three year-event free survival (EFS) and overall survival (OS) were 38% and 44%, respectively. Non-relapse mortality (NRM) at day 100 was 19%. Cumulative incidence of grade III-IV acute graft versus host disease (GVHD) at day 100 was 16% and moderate/severe chronic GVHD at 3 years 34%. Active disease at allo-SCT (HR 1.95, p = 0.039) (HR 2.19, p = 0.019), HCT-CI ≥ 2 (2.45, p = 0.002) (HR 2.33, p = 0.006) and donor age >37 years (HR 2.75, p = 0.014) (HR 1.98, p = 0.043) were the only independent variables both for PFS and OS, respectively. NRM was significantly modified by HCT-CI ≥ 2 (HR 4.8, p = 0.008), previous ASCT (HR 4.4, p = 0.048) and grade III-IV acute GVHD on day 100 (HR 6.13, p = 0.016). Our data confirmed that allo-SCT is a curative option for patients with R/R DLBCL, displaying adequate results for fit patients with chemosensitive disease receiving an allo-SCT from a young donor.

Recent advances in cellular therapy for malignant lymphoma

Cellular therapies for malignant lymphoma include autologous or allogeneic hematopoietic stem cell transplantation (HSCT) and adaptive cellular therapy using EBV-specific T cells, cytokine-induced killer (CIK) cells, NKT cells, NK cells, chimeric antigen receptor T (CAR-T) cells and chimeric antigen receptor NK (CAR-NK) cells. In this review we discusses recent advances of these cellular therapies and consider ways to optimize these therapies. Not only a single strategy using one of these cellular therapies, but also multi-disciplinary treatment combines with antibodies, such as an anti-tumor antibody and an immune checkpoint antibody, may be more effective for relapsed and refractory lymphoma.

Outpatient Haploidentical Stem Cell Transplantation Using Post-Transplant Cyclophosphamide Is Safe and Feasible

BACKGROUND

Hematopoietic stem cell transplantation (HSCT) feasibility has increased in the last decades because of haplo-HSCT, changes in chemotherapy schedules, and the possibility of an outpatient-based HSCT. The main barriers remain in low-middle income countries. There is a lack of information regarding haplo-HSCT with a myeloablative (MAC) regimen on an outpatient basis.

OBJECTIVES

Our primary objective was to determine if outpatient haplo-HSCT was feasible.

STUDY DESIGN

Single center, retrospective cohort, n=60 adult patients undergoing Haplo-HSCT. Descriptive statistical analysis, univariate and multivariate comparison.

PATIENTS AND METHOD

We analyzed 60 adult patients transplanted with an intended haplo-HSCT on an outpatient basis from 2015 to 2019 in our unit. A multivariate analysis was performed on risk factors for hospitalization.

RESULTS

Median age was 27 years (15-64). All patients underwent conditioning as outpatients, and none required hospitalization before day 0. Thirteen patients (21.6%) were followed completely in the outpatient clinic and 47 (78.3%) required hospitalization in a median of 3 days after infusion (range, 1-14). The median length of stay (LOS) was 8 days (IQR, 3-17). Fever secondary to cytokine release syndrome (CRS) was the most common reason for hospitalization occurring in 43/47 (91.5%), 4 were related to infection and 36 were related to CRS. In the univariate analysis, CRS, slower engraftment, and female sex were associated with the need for hospitalization. In the multivariate analysis, only CRS remained significant (OR 9.14 [95%CI, 1.58-56.46]). The 2-year overall survival (OS) was 41.7% for ambulatory transplant vs. 38% for those requiring hospitalization (P = 0.12). The 2-year event-free survival (EFS) was 33% for outpatient patients and 16.7% for those hospitalized (log-rank, P = 0.062).

CONCLUSIONS

We demonstrated the feasibility and safety of carrying out an outpatient haplo-HSCT, potentially resulting in cost savings and perhaps a higher quality of life.

Immunotherapy with cells

Both older and newer cell therapies have demonstrated impressive responses in otherwise poor-prognosis lymphomas. Consequently, cellular therapy now plays a major role in the management of many non-Hodgkin lymphomas. In this article, we examine the role of chimeric antigen receptor (CAR) T cells, allogeneic stem cell transplantation, and virus-directed T cells for treatment of lymphomas. We review the current indications for CAR T cells and discuss our clinical approach to selecting and treating patients with aggressive B-cell lymphomas to receive CD19-directed CAR T cells. In addition, we highlight newer cell therapies and provide an overview of promising future approaches that have the potential to transform immunotherapy with cells to treat lymphomas.

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

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

Isolation of a Highly Purified HSC-enriched CD34+CD90+CD45RA- Cell Subset for Allogeneic Transplantation in the Nonhuman Primate Large-animal Model

Allogeneic hematopoietic stem cell transplantation (allo-HCT) is a common treatment for patients suffering from different hematological disorders. Allo-HCT in combination with hematopoietic stem cell (HSC) gene therapy is considered a promising treatment option for millions of patients with HIV+ and acute myeloid leukemia. Most currently available HSC gene therapy approaches target CD34-enriched cell fractions, a heterogeneous mix of mostly progenitor cells and only very few HSCs with long-term multilineage engraftment potential. As a consequence, gene therapy approaches are currently limited in their HSC targeting efficiency, very expensive consuming huge quantities of modifying reagents, and can lead to unwanted side effects in nontarget cells. We have previously shown that purified CD34⁺CD90⁺CD45RA⁻ cells are enriched for multipotent HSCs with long-term multilineage engraftment potential, which can reconstitute the entire hematopoietic system in an autologous nonhuman primate transplant model. Here, we tested the feasibility of transplantation with purified CD34⁺CD90⁺CD45RA⁻ cells in the allogeneic setting in a nonhuman primate model.

Impact of type of reduced-intensity conditioning regimen on the outcomes of allogeneic haematopoietic cell transplantation in classical Hodgkin lymphoma

Reduced-intensity conditioning (RIC) allogeneic haematopoietic cell transplantation (allo-HCT) is a curative option for select relapsed/refractory Hodgkin lymphoma (HL) patients; however, there are sparse data to support superiority of any particular conditioning regimen. We analyzed 492 adult patients undergoing human leucocyte antigen (HLA)-matched sibling or unrelated donor allo-HCT for HL between 2008 and 2016, utilizing RIC with either fludarabine/busulfan (Flu/Bu), fludarabine/melphalan (Flu/Mel140) or fludarabine/cyclophosphamide (Flu/Cy). Multivariable regression analysis was performed using a significance level of <0·01. There were no significant differences between regimens in risk for non-relapse mortality (NRM) (P = 0·54), relapse/progression (P = 0·02) or progression-free survival (PFS) (P = 0·14). Flu/Cy conditioning was associated with decreased risk of mortality in the first 11 months after allo-HCT (HR = 0·28; 95% CI = 0·10-0·73; P = 0·009), but beyond 11 months post allo-HCT it was associated with a significantly higher risk of mortality, (HR = 2·46; 95% CI = 0·1.32-4·61; P = 0·005). Four-year adjusted overall survival (OS) was similar across regimens at 62% for Flu/Bu, 59% for Flu/Mel140 and 55% for Flu/Cy (P = 0·64), respectively. These data confirm the choice of RIC for allo-HCT in HL does not influence risk of relapse, NRM or PFS. Although no OS benefit was seen between Flu/Bu and Flu/Mel 140; Flu/Cy was associated with a significantly higher risk of mortality beyond 11 months from allo-HCT (possibly due to late NRM events).

The economic burden to payers of patients with diffuse large B-cell lymphoma during the treatment period by line of therapy

We retrospectively analyzed treatment patterns and healthcare costs among patients diagnosed with diffuse large B-cell lymphoma (DLBCL) during each line of therapy (LOT) using data from the IBM^® MarketScan^® Commercial and Medicare Supplemental Databases from January 2011 to May 2017. Patients were included if they had a diagnosis of DLBCL, ≥12 months of disease-free continuous enrollment prediagnosis, and ≥1 month of postdiagnosis follow-up. Of 2066 eligible patients receiving first-line treatment, 17% (n = 340) received second-line treatment; of these, 23% (n = 77) received third-line treatment. Mean healthcare expenditures (treatment duration) for first, second, and third LOTs were $111,314 (124.5 days), $88,472 (80.8 days), and $103,365 (70.9 days), respectively. When adjusted to 30-day period costs, first, second, and third LOT healthcare expenditures increased to $26,825, $32,857, and $43,854, respectively. Patients with newly diagnosed and relapsed/refractory DLBCL incur a significant cost burden (for payers), and such costs increase as patients proceed through subsequent LOTs.

Allogeneic transplantation in elderly patients ≥65 years with non-Hodgkin lymphoma: a time-trend analysis

Allogeneic hematopoietic cell transplantation (allo-HCT) is a curative therapy for relapsed/refractory and high-risk non-Hodgkin lymphoma (NHL). However, no large studies have evaluated allo-HCT utilization in elderly NHL patients (≥65 years). Using the CIBMTR registry, we report a time-trend analysis of 727 NHL patients (≥65 years) undergoing the first allo-HCT from 2000 to 2015 in the United States (US). Study cohorts were divided by time period: 2000-2005 (N = 76) vs. 2006-2010 (N = 238) vs. 2011-2015 (N = 413). Primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), relapse/progression (R/P), and non-relapse mortality (NRM). Median age at transplant, use of reduced-intensity conditioning, and graft source remained stable, while use of unrelated donors increased in the most current era. The 1-year probabilities of NRM from 2000 to 2005 vs. 2006-2010 vs. 2011-2015 were 24% vs. 19% vs. 21%, respectively (p = 0.67). Four-year probability of R/P was similar among the three cohorts: 48% (2000-2005), 40% (2006-2010), and 40% (2011-2015) (p = 0.39). The 4-year probabilities of PFS and OS (2000-2005 vs. 2006-2010 vs. 2011-2015) showed significantly improved outcomes in more recent time periods: 17% vs. 31% vs. 30% (p = 0.02) and 21% vs. 42% vs. 44% (p < 0.001), respectively. Utilization of allo-HCT increased in elderly NHL patients in the US since 2000 with improving survival outcomes.

Hematopoietic-cell transplantation for lymphoma in the era of genetically engineered cellular therapy: it's not quite time to scrap the old vehicle for the new car

PURPOSE OF REVIEW

Second-line platinum-based salvage chemotherapy followed by high-dose chemotherapy and autologous hematopoietic-cell transplantation (AHCT) has remained the standard of care (SOC) for relapsed and primary refractory (r/r) diffuse large B-cell lymphoma (DLBCL) for greater than 2 decades. In the postrituximab era, this strategy has yielded disappointing outcomes for r/r patients with curability in less one-quarter of the patients by intention-to-treat.

RECENT FINDINGS

Given the Food and Drug Administration (FDA) approval of chimeric antigen receptor (CAR) modified T cells directed against CD19 (CD19 CAR T) for DLBCL following two lines of therapy and/or failed AHCT, encouragement with this therapy in the second line for r/r patients has naturally prompted randomized phase III studies against the aforementioned SOC. The predominant hurdle to procession to AHCT is chemotherapy sensitivity after platinum-based salvage therapy.

SUMMARY

In this review, we will discuss recent investigations to improve response rates in r/r DLBCL with the intent of proceeding to potentially curative AHCT, as well as investigations to decrease progression post-AHCT. In addition, data regarding currently FDA approved CD19 CAR T cells will be reviewed. Within 2-3 years, we will know if the multicenter/multinational studies of CD19 CAR T will replace SOC salvage therapy and AHCT in the second-line. The role of allogeneic HCT will also be briefly reviewed in the context of these therapies.

Risk factors predicting graft-versus-host disease and relapse-free survival after allogeneic hematopoietic stem cell transplantation in relapsed or refractory non-Hodgkin's lymphoma

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is still considered a definitive curative modality for refractory or relapsed non-Hodgkin’s lymphoma (NHL). However, transplant-related morbidity and mortality remain a considerable challenge. The graft-versus-host disease (GVHD)–free with relapse-free survival (GRFS) rate and GRFS-related prognostic factors have not been fully examined for NHL alone. We evaluated 104 consecutive patients with refractory or relapsed aggressive NHL receiving allo-HSCT at a single institution. With a median follow-up of 31.5 months, the estimated 3-year overall survival (OS), disease-free survival (DFS), the cumulative incidence rates of relapse, and non-relapse mortality were 45.9%, 45.9%, 36.0%, and 17.0%, respectively. The patients with overall grades III–IV acute GVHD had markedly inferior OS and DFS (p = 0.040 for OS and p = 0.028 for DFS). However, patients with more than mild stage chronic GVHD showed superior OS and DFS (p = 0.004 and p = 0.008, respectively). The 1- and 3-year GRFS rates were 44.5% and 36.9%, respectively. The negative bone marrow involvement at diagnosis, chemosensitive disease status, and fewer exposure lines of chemotherapy before transplantation significantly increased the GRFS incidence. However, no transplant-associated factors were related to GRFS incidence. Furthermore, applying dynamic GRFS method which excepted patients whose chronic GVHD was fully resolved within short-period, survival rate significantly increased over time (36.9% vs. 41.9%, p = 0.045 for conventional GRFS vs. dynamic GRFS at 3 years after transplantation). In conclusion, these results suggest that GRFS is also a useful endpoint to assess transplant outcomes, and the dynamic GRFS calculation, including rapidly manageable chronic GVHD, is a more practical method for patients with refractory or relapsed heterogenous subtypes of NHL.

Impact of Donor Type and Melphalan Dose on Allogeneic Transplantation Outcomes for Patients with Lymphoma

We analyzed 186 patients with lymphoma who underwent allogeneic stem cell transplantation (ASCT) with fludarabine-melphalan (FM) conditioning and different types of donors (25 haploidentical [HD], 98 matched unrelated [MUD], and 63 matched related [MRD]) at our institution between September 2009 and January 2018. Patients received fludarabine 160 mg/m² (40 mg/m²/day for 4 days) in combination with 1 dose of melphalan 140 mg/m² (FM140) or 100 mg/m² (FM100). Engraftment was similar among the 3 groups (92%, 89%, and 98%, respectively; P = .7). The 6-month cumulative incidence of grade III-IV acute graft-versus-host disease (GVHD) was 4% in the HD group, 14% in the MUD group, and 8% in the MRD group (P not significant), and the respective 3-year cumulative incidence of chronic GVHD was 5%, 16%, and 26% (P not significant). The respective 3-year nonrelapse mortality and relapse rates were 31%, 32%, and 10% (HD versus MUD, P = .9; HD versus MRD, P = .02) and 15%, 21%, and 39% (HD versus MUD, P = .4; HD versus MRD, P = .04). At 3 years, progression-free survival (PFS) was 59%, 44%, and 46% (P not significant); overall survival (OS) was 52%, 54%, and 67% (P not significant); and GVHD-free, relapse-free survival was 39%, 31%, and 24% (P not significant). No differences in the 3-year PFS (57% versus 43%; P = .3) and OS (64% versus 58%; P = .7) were seen between patients receiving FM100 and those receiving FM140. Our data demonstrate that in patients with lymphoma, ASCT with HD transplants have similar outcomes as ASCT with HLA-matched transplants, and the FM100 conditioning regimen appears to be at least as effective as the FM140 regimen.

Outcomes of Patients with Recurrent and Refractory Lymphoma Undergoing Allogeneic Hematopoietic Cell Transplantation with BEAM Conditioning and Sirolimus- and Tacrolimus-Based GVHD Prophylaxis

The current standard of care for patients with Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL) is high-dose conditioning followed by autologous stem cell transplantation (ASCT). For some patients (ie, those with highest-risk disease, insufficient stem cell numbers after mobilization, or bone marrow involvement) allogeneic hematopoietic cell transplantation (alloHCT) offers the potential for cure. However, the majority of patients undergoing alloHCT receive reduced-intensity conditioning as a preparative regimen, and studies assessing outcomes of patients after alloHCT with myeloablative conditioning are limited. In this retrospective study, we reviewed outcomes of 22 patients with recurrent and refractory NHL who underwent alloHCT with myeloablative BEAM conditioning and received tacrolimus/sirolimus as graft-versus-host disease (GVHD) prophylaxis at City of Hope between 2005 and 2018. With a median follow-up of 2.6 years (range, 1.0 to 11.2 years), the probabilities of 2-year overall survival and event-free survival were 58.3% (95% confidence interval [CI], 35.0% to 75.8%) and 45.5% (95% CI, 24.4% to 64.3%), respectively. The cumulative incidence of grade II to IV acute GVHD was 45.5% (95% CI, 23.8% to 64.9%), with only 1 patient developing grade IV acute GVHD. However, chronic GVHD was seen in 55% of the patients (n = 12). Of the 22 eligible patients, 2 had undergone previous ASCT and 2 had undergone previous alloHCT. Both patients with previous ASCT developed severe regimen-related toxicity. Patients who underwent alloHCT with chemorefractory disease had lower survival rates, with 1-year OS and EFS of 44.4% and 33.0%, respectively. In conclusion, alloHCT with a BEAM preparative regimen and tacrolimus/sirolimus-based GVHD should be considered as an alternative option for patients with highest-risk lymphoma whose outcomes are expectedly poor after ASCT.

The Impact of Advanced Patient Age on Mortality after Allogeneic Hematopoietic Cell Transplantation for Non-Hodgkin Lymphoma: A Retrospective Study by the European Society for Blood and Marrow Transplantation Lymphoma Working Party

More than 60% of patients with non-Hodgkin lymphoma (NHL) are age >60 years at presentation. The purpose of this study was to compare the potential risks and benefits of allogeneic hematopoietic cell transplantation (alloHCT) in elderly patients with NHL with younger patients in a large sample, also taking into account comorbidity information. All patients age ≥18 years who had undergone alloHCT from a matched sibling or unrelated donor for NHL between 2003 and 2013 and were registered with the European Society for Blood and Marrow Transplantation were eligible for the study. The primary study endpoint was 1-year nonrelapse mortality (NRM). A total of 3919 patients were eligible and were categorized by age: young (Y), 18 to 50 y (n = 1772); middle age (MA), 51 to 65 y (n = 1967); or old (O), 66 to 77 y (n = 180). Follicular lymphoma was present in 37% of the patients; diffuse large B cell lymphoma, in 30%; mantle cell lymphoma, in 21%, and peripheral T cell lymphoma, in 11%. At the time of alloHCT, 85% of the patients were chemosensitive and 15% were chemorefractory. With a median follow-up of 4.5 years in survivors, NRM at 1 year was 13% for the Y group. 20% for the MA group, and 33% for the O group (P <.001), whereas relapse incidence and overall survival (OS) at 3 years in the 3 groups were 30%, 31%, and 28% (P = .355) and 60%, 54%, and 38% (P <.001), respectively. Multivariable adjustment for confounders, including sex, NHL subset, time from diagnosis, chemosensitivity, donor, and conditioning, confirmed older age as a significant predictor for NRM and OS, but not for relapse risk. Although comorbidity was a significant predictor of NRM in a subset analysis restricted to the 979 patients with comorbidity information available, age retained its significant impact on NRM. In conclusion, our data show that alloHCT in patients age >65 y provides similar NHL control as seen in younger patients but is associated with a higher NRM that is not fully explained by comorbidity. Thus, although alloHCT is feasible and effective in very old patients, the increased NRM risk must be taken into account when assessing the indication for alloHCT for NHL in this age group.

Translating anti-CD19 CAR T-cell therapy into clinical practice for relapsed/refractory diffuse large B-cell lymphoma

Chimeric antigen receptor T cells demonstrate efficacy in B-cell malignancies, leading to US Food and Drug Administration approval of axicabtagene ciloleucel (October 2017) and tisagenlecleucel (May 2018) for large B-cell lymphomas after 2 prior lines of therapy. Durable remissions are seen in 30% to 40% of study-treated patients, but toxicities of cytokine release syndrome and neurotoxicity require administration in specialized centers. This article reviews data of current diffuse large B-cell lymphoma management, focusing on axicabtagene ciloleucel, tisagenlecleucel, and lisocabtagene maraleucel.

Current Approaches to Mantle Cell Lymphoma: Diagnosis, Prognosis, and Therapies

Mantle cell lymphoma (MCL) is a unique lymphoma subtype, both biologically and clinically. Virtually all cases are characterized by a common genetic lesion, t(11;14), resulting in overexpression of cyclin D1. The clinical course is moderately aggressive, and the disease is considered incurable. Considerable biologic and clinical heterogeneity exists, with some patients experiencing a rapidly progressive course, while others have disease that is readily managed. New tools exist for risk stratification and may allow for a more personalized approach in the future. Landmark studies have been completed in recent years and outcomes appear to be improving. Randomized clinical trials have clarified the role of high-dose cytarabine (Ara-C) for younger patients and have demonstrated a role for maintenance rituximab therapy. Multiple areas of uncertainty remain, however, and are the focus of ongoing research. This review focuses on (1) strategies to differentiate between aggressive and less aggressive cases, (2) understanding who should receive hematopoietic stem cell transplantation, and (3) the role for maintenance therapy in MCL.

[Allogeneic haematopoietic cell transplantation for diffuse large B cell lymphoma: Guidelines from the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC)]

Despite great improvements in the outcome of patients with lymphoma, some may still relapse or present with primary refractory disease. In these situations, allogeneic hematopoietic cell transplantation is a potentially curative option, this is true particularly in the case of after autologous stem cell transplantation if remission can be achieved. Recently, novel agents such as anti-PD1 and BTK inhibitors have started to challenge the use of allogeneic hematopoietic cell transplantation for relapsed or refractory lymphoma. During the 2016 annual workshop of the Francophone Society of Bone Marrow Transplantation and Cellular Therapy (SFGM-TC), we performed a comprehensive review of the literature published in the last 10 years and established guidelines to clarify the indications and transplant modalities in this setting. This section specifically reports on our conclusions regarding diffuse large B cell lymphoma.

PD-1 blockade for relapsed lymphoma post-allogeneic hematopoietic cell transplant: high response rate but frequent GVHD

Given the limited treatment options for relapsed lymphoma post-allogeneic hematopoietic cell transplantation (post-allo-HCT) and the success of programmed death 1 (PD-1) blockade in classical Hodgkin lymphoma (cHL) patients, anti-PD-1 monoclonal antibodies (mAbs) are increasingly being used off-label after allo-HCT. To characterize the safety and efficacy of PD-1 blockade in this setting, we conducted a multicenter retrospective analysis of 31 lymphoma patients receiving anti-PD-1 mAbs for relapse post-allo-HCT. Twenty-nine (94%) patients had cHL and 27 had ≥1 salvage therapy post-allo-HCT and prior to anti-PD-1 treatment. Median follow-up was 428 days (range, 133-833) after the first dose of anti-PD-1. Overall response rate was 77% (15 complete responses and 8 partial responses) in 30 evaluable patients. At last follow-up, 11 of 31 patients progressed and 21 of 31 (68%) remain alive, with 8 (26%) deaths related to new-onset graft-versus-host disease (GVHD) after anti-PD-1. Seventeen (55%) patients developed treatment-emergent GVHD after initiation of anti-PD-1 (6 acute, 4 overlap, and 7 chronic), with onset after a median of 1, 2, and 2 doses, respectively. GVHD severity was grade III-IV acute or severe chronic in 9 patients. Only 2 of these 17 patients achieved complete response to GVHD treatment, and 14 of 17 required ≥2 systemic therapies. In conclusion, PD-1 blockade in relapsed cHL allo-HCT patients appears to be highly efficacious but frequently complicated by rapid onset of severe and treatment-refractory GVHD. PD-1 blockade post-allo-HCT should be studied further but cannot be recommended for routine use outside of a clinical trial.

Development of a modified prognostic index for patients with aggressive adult T-cell leukemia-lymphoma aged 70 years or younger: possible risk-adapted management strategies including allogeneic transplantation

Adult T-cell leukemia-lymphoma is a distinct type of peripheral T-cell lymphoma caused by human T-cell lymphotropic virus type I. Although allogeneic stem cell transplantation after chemotherapy is a recommended treatment option for patients with aggressive adult T-cell leukemia-lymphoma, there is no consensus about indications for allogeneic stem cell transplantation because there is no established risk stratification system for transplant eligible patients. We conducted a nationwide survey of patients with aggressive adult T-cell leukemia-lymphoma in order to construct a new, large database that includes 1,792 patients aged 70 years or younger with aggressive adult T-cell leukemia-lymphoma who were diagnosed between 2000 and 2013 and received intensive first-line chemotherapy. We randomly divided patients into two groups (training and validation sets). Acute type, poor performance status, high soluble interleukin-2 receptor levels (> 5,000 U/mL), high adjusted calcium levels (≥ 12 mg/dL), and high C-reactive protein levels (≥ 2.5 mg/dL) were independent adverse prognostic factors used in the training set. We used these five variables to divide patients into three risk groups. In the validation set, median overall survival for the low-, intermediate-, and high-risk groups was 626 days, 322 days, and 197 days, respectively. In the intermediate- and high-risk groups, transplanted recipients had significantly better overall survival than non-transplanted patients. We developed a promising new risk stratification system to identify patients aged 70 years or younger with aggressive adult T-cell leukemia-lymphoma who may benefit from upfront allogeneic stem cell transplantation. Prospective studies are warranted to confirm the benefit of this treatment strategy.

PD-1-PD-L1 immune-checkpoint blockade in B-cell lymphomas

Cancer cells can escape T-cell-mediated cellular cytotoxicity by exploiting the inhibitory programmed cell-death protein 1 (PD-1)/programmed cell death 1 ligand 1 (PD-L1) immune checkpoint. Indeed, therapeutic antibodies that block the PD-1-PD-L1 axis induce durable clinical responses against a growing list of solid tumours. B-cell lymphomas also leverage this checkpoint to escape immune recognition, although the outcomes of PD-1-PD-L1 blockade, and the correlations between PD-L1 expression and treatment responses, are less-well elucidated in these diseases than in solid cancers. Nevertheless, in patients with Hodgkin lymphoma, amplification of the gene encoding PD-L1 is commonly associated with increased expression of this protein on Reed-Sternberg cells. Correspondingly, PD-1 blockade with nivolumab has been demonstrated to result in response rates as high as 87% in unselected patients with relapsed and/or refractory Hodgkin lymphoma, leading to the FDA approval of nivolumab for this indication in May 2016. The PD-1/PD-L1 axis is probably also important for immune evasion of B-cell lymphomas with a viral aetiology, including those associated with human immunodeficiency virus (HIV) and Epstein-Barr virus (EBV). This Review is focused on the role of PD-1-PD-L1 blockade in unleashing host antitumour immune responses against various B-cell lymphomas, and summarizes the clinical studies of this approach performed to date.

Allogeneic Transplantation for Relapsed Waldenström Macroglobulinemia and Lymphoplasmacytic Lymphoma

Waldenström macroglobulinemia/lymphoplasmacytic lymphoma (WM/LPL) is characterized by lymphoplasmacytic proliferation, lymph node and spleen enlargement, bone marrow involvement, and IgM production. Treatment varies based on the extent and biology of disease. In some patients, the use of allogeneic hematopoietic cell transplantation (alloHCT) may have curative potential. We evaluated long-term outcomes of 144 patients who received adult alloHCT for WM/LPL. Data were obtained from the Center for International Blood and Marrow Transplant Research database (2001 to 2013). Patients received myeloablative(n = 67) or reduced-intensity conditioning (RIC; n = 67). Median age at alloHCT was 53 years, and median time from diagnosis to transplantation was 41 months. Thirteen percent (n = 18) failed prior autologous HCT. About half (n = 82, 57%) had chemosensitive disease at the time of transplantation, whereas 22% had progressive disease. Rates of progression-free survival, overall survival, relapse, and nonrelapse mortality at 5 years were 46%, 52%, 24%, and 30%, respectively. Patients with chemosensitive disease and better pretransplant disease status experienced significantly superior overall survival. There were no significant differences in progression-free survival based on conditioning (myeloablative, 50%, versus RIC, 41%) or graft source. Conditioning intensity did not impact treatment-related mortality or relapse. The most common causes of death were primary disease and graft-versus-host disease (GVHD). AlloHCT yielded durable survival in select patients with WM/LPL. Strategies to reduce mortality from GVHD and post-transplant relapse are necessary to improve this approach.