Outcome of autologous hematopoietic stem cell transplant in older patients with B cell lymphoma when selected for fitness and chemosensitive disease

How can we improve the successful identification of patients suitable for CAR-T cell therapy?

INTRODUCTION

In recent years, chimeric antigen receptor T (CAR-T) cell therapy has resulted in a breakthrough in the treatment of patients with refractory or relapsed hematological malignancies. However, the identification of patients suitable for CAR-T cell therapy needs to be improved.

AREAS COVERED

CAR-T cell therapy has demonstrated excellent efficacy in hematological malignancies; however, views on determining when to apply CAR-T cells in terms of the evaluation of patient characteristics remain controversial.

EXPERT OPINION

We reviewed the current feasibility and challenges of CAR-T cell therapy in the most common hematological malignancies and classified them according to the disease type and treatment priority, to guide clinicians and researchers in applying and investigating CAR-T cells furtherly.

Busulfan, Melphalan, and Etoposide (BuME) Showed an Equivalent Effect to Busulfan, Cyclophosphamide, and Etoposide (BuCE) as Conditioning Therapy for Autologous Stem Cell Transplantation in Patients with Relapsed or High-Risk Non-Hodgkin's Lymphoma: A Multicenter Randomized Phase II Study bythe Consortium for Improving Survival of Lymphoma (CISL)

PURPOSE

High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is the standard management for relapsed or high-risk non-Hodgkin's lymphoma (NHL). We reported the busulfan, melphalan, and etoposide (BuME) conditioning regimen was effective in patients with relapsed or high-risk NHL. Moreover, the busulfan, cyclophosphamide, and etoposide (BuCE) conditioning regimen has been used widely in ASCT for NHL. Therefore, based on these encouraging results, this randomized phase II multicenter trial compared the outcomes of BuME and BuCE as conditioning therapies for ASCT in patients with NHL.

MATERIALS AND METHODS

Patients were randomly assigned to receive either BuME (n=36) or BuCE (n=39). The BuME regimen was comprised of busulfan (3.2 mg/kg/day, intravenously) administered on days -7, -6, and -5, etoposide (400 mg/m2 intravenously) on days -5 and -4, and melphalan (50 mg/m2/day intravenously) on days -3 and -2. The BuCE regimen was comprised of busulfan (3.2 mg/kg/day intravenously) on days -7, -6, and -5, etoposide (400 mg/m2/day intravenously) on days -5 and -4, and cyclophosphamide (50 mg/kg/day intravenously) on days -3 and -2. The primary endpoint was 2-year progression-free survival (PFS).

RESULTS

Seventy-five patients were enrolled. Eleven patients (30.5%) in the BuME group and 13 patients (33.3%) in the BuCE group had disease progression or died. The 2-year PFS rate was 65.4% in the BuME group and 60.6% in the BuCE group (p=0.746). There were no non-relapse mortalities within 100 days after transplantation.

CONCLUSION

There were no significant differences in PFS between the two groups. Therefore, busulfan-based conditioning regimens, BuME and BuCE, may be important treatment substitutes for the BCNU-containing regimens.

Impact of Implementing a Bendamustine-Based Conditioning Regimen on Outcomes of Autologous Stem Cell Transplantation in Lymphoma while Novel Cellular Therapies Emerge

With the advent of new cellular and targeted therapies, treatment options for relapsed and refractory (r/R) lymphomas have multiplied, and the optimal approach offering the best outcomes remains a matter of passionate debate. High-dose chemotherapy followed by autologous stem cell transplantation (ASCT) is still considered a treatment option for patients with chemosensitive lymphoma when cure is the expected goal. The myeloablative conditioning regimen preceding the stem cell infusion is considered the effective component of this approach. Carmustine (BCNU)-based preparative regimens, such as BEAM and BEAC, are considered the standard of care and have shown efficacy and low nonrelapse mortality (NRM). Comparative studies between conditioning regimens have failed to identify a better option. After a BCNU drug shortage in Canada followed by a steep increase in price, we elected to substitute BCNU for bendamustine (benda) in the preparative regimen. The purpose of this substitution was to improve response while preserving safety and controlling costs. From May 2015 to May 2018, a total of 131 consecutive lymphoma patients received benda-EAM conditioning. These patients were compared with 96 consecutive patients who received BCNU-based conditioning from January 2012 to May 2015. Apart from conditioning, supportive care measures were the same in the 2 groups. Patients receiving benda were older (55.7 years versus 51.1 years; P = .002). The development of grade ≥3 mucositis was more frequent with benda conditioning (39.5% versus 7.8%; P < .001) leading to a greater requirement for parenteral nutrition (48.9% versus 21.9%; P < .001). A transient creatinine increase >1.5 times the upper limit of normal (15.3% versus 4.2%; P < .008) and intensive care unit admission (6.9% versus 1.1%; P < .029) were more frequent with benda; however, there were no between-group differences in cardiac, pulmonary, or liver toxicity and NRM. With a median follow-up of 48 months for the benda group and 60 months for the BCNU group, benda was associated with significantly better progression-free survival (71% versus 61%; P = .040; hazard ratio [HR], 1.6; 95% confidence interval [CI], 1.0 to 2.7) and overall survival (86% vs 71%; P = .0066; HR, 2.6; 95% CI, 1.3 to 5.4) compared with BCNU-based conditioning regimens. While novel therapies emerge, our study demonstrates that benda-EAM is safe and effective and should be considered a valid alternative to BCNU conditioning to improve outcomes of patients with chemosensitive r/R lymphomas undergoing ASCT.

Transplant-ineligible but chimeric antigen receptor T-cells eligible: a real and relevant population

Autologous stem cell transplantation (ASCT) and chimeric antigen receptor (CAR) T-cells are two therapeutic options for relapsed/refractory diffuse large B-cell lymphoma. Both are intensive and potentially curative therapies but differ in their efficacy and toxicity. ASCT may be offered to 'fit' patients (i.e. usually young with limited comorbidities) with chemosensitive disease. On the other hand, real world studies have shown that CAR T-cells may be safely administered to less fit and older patients. Thus, there is a potentially significant population of patients who may be offered CAR T-cell therapy despite not being eligible for ASCT. As the relative role of ASCT and CAR T-cells evolves, recognising and defining this population may be increasingly relevant. Here, we review criteria which may help identify this 'ASCT-ineligible but CAR T-cells eligible' population of patients.

Evaluation of the Impact of Autologous Hematopoietic Stem Cell Transplantation on the Quality of Life of Older Patients with Lymphoma

High-dose chemotherapy (HDT) followed by autologous hematopoietic stem cell transplantation (AHSCT) improves survival in patients with chemosensitive non-Hodgkin lymphoma (NHL). Determination of the Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI) has contributed to improve patient selection while allowing for prediction of nonrelapse mortality. We previously demonstrated the efficacy and safety of AHSCT in a cohort of older patients with chemosensitive NHL. Quality of life following AHSCT still has not been widely evaluated. The goal of this study was to assess the long-term quality of life of elderly patients surviving AHSCT. This single-center, Research and Ethics Committee-approved study investigated QoL in survivors of AHSCT for the treatment of NHL in a cohort of older patients. Inclusion criteria were defined as patients age ≥60 years who underwent AHSCT for NHL between January 1, 2008, and January 1, 2015, at our center. Fifty-nine patients from the original cohort of 90 survived at a median of 50 months post-AHSCT. Forty-seven (79.7%) of those patients agreed to complete the QoL assessment questionnaires after the transplantation and are included in this report. All patients provided signed informed consent. We used the EQ-5D instrument to assess mobility, self-care, usual activities, pain/discomfort, and anxiety/depression and the Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT) questionnaire to assess physical, social/family, emotional, and functional well-being and BMT-specific concerns. With both tools, a higher score indicates better QoL. Fifteen percent of patients were in relapse at the time of the QoL assessment. In the EQ-5D, few patients (9%) reported severe impairment, which requires significant negative effects in 4 or 5 domains. Lower Karnofsky Performance Status (KPS) score at the time of transplantation was negatively correlated with mobility (P= .001), self-care (P= .001), and usual activities (P= .007) dysfunction. Anxiety was significant for patients in relapsed after transplantation (P= .002). FACT-BMT questionnaire results demonstrated that physical, social, and emotional well-being were all well preserved after the transplantation, whereas functional well-being was more variable among patients. Relapse was associated with impaired functional well-being (P= .007) and lower total FACT-BMT score (P= .014). Other comparators, including the conditioning regimen, sex, age subgroups (<65 or ≥65 years), HCT-CI score, and disease status at transplantation, did not impact any of these outcomes. This study demonstrates that physical, social, and functional well-being are preserved in older patients following AHSCT. Low KPS score before AHSCT is a predictor of disability at distance from AHSCT. Relapse following AHSCT remains the most significant impediment to maintaining a good QoL. Innovative interventions to improve performance status before transplantation and measures to prevent relapse thereafter should be investigated to improve survival and QoL.