Phase II study of bendamustine combined with rituximab in relapsed/refractory mantle cell lymphoma: efficacy, tolerability, and safety findings

Real-World Evidence of Relapsed/Refractory Mantle Cell Lymphoma Patients and Treatments: A Systematic Review

Introduction

Mantle cell lymphoma (MCL) is an incurable disease with an aggressive clinical course, and most patients eventually relapse after chemotherapy. Targeted therapies developed for relapsed/refractory MCL have been approved based on clinical trial data. However, real-world setting data are scarce and scattered.

Areas Covered

This systematic review aimed to collect, synthesize, and describe the characteristics and treatment outcomes of patients with relapsed/refractory MCL after receiving a second or subsequent line of therapy in the real-world setting.

Expert Opinion

R/R MCL is clinically and biologically heterogeneous and still represents a therapeutic challenge, with high-risk and early relapsed patients remaining an unmet medical need. This systematic review is limited by the quality of the available data and the difficulty of comparing outcomes in R/R MCL due to the heterogeneity of the disease, but the results suggest that covalent BTKis should be positioned as second-line therapy, followed by CAR T-cells in BTK-i-relapsed patients. Chemo-free and combination therapies with established chemoimmunotherapy backbones in the relapsed and front-line settings have been recently developed, and front-line options are being improved to move targeted and cellular therapies to earlier lines, including front-line therapy, in elderly and younger fit patients. In the upcoming years, many new targeted agents will play an important role and will be incorporated to the routine practice as their sequence, and outcomes in unselected patients are determined.

Post-marketing risk analysis of bendamustine: a real-world approach based on the FAERS database

Objective: Bendamustine was approved for treating chronic lymphocytic leukemia and indolent B-cell non-Hodgkin lymphoma. Despite its therapeutic benefits, the long-term safety of bendamustine in a large population remains inadequately understood. This study evaluates the adverse events (AEs) associated with bendamustine, using a real-world pharmacovigilance database to support its clinical application. Methods: We conducted a post-marketing risk analysis to assess the association between bendamustine and its AEs. Data were extracted from the US FDA's Adverse Event Reporting System (FAERS), covering the period from January 2017 to September 2023. The characteristics of bendamustine-associated AEs and the onset time were further analyzed. Statistical analysis was performed using MYSQL 8.0, Navicat Premium 15, Microsoft EXCEL 2016, and Minitab 21.0. Results: 9,461,874 reports were collected from the FAERS database, 9,131 identified bendamustine as the "primary suspected" drug. We identified 331 significant disproportionality preferred terms (PTs). Common AEs included pyrexia, neutropenia, infusion site reaction, progressive multifocal leukoencephalopathy (PML), injection site vasculitis, and pneumonia-all documented on bendamustine's label. Notably, 16 unexpected and significant AEs were discovered, including hypogammaglobulinemia, which is concerning due to its potential to increase infection susceptibility following bendamustine treatment. Other significant findings were anaphylactic reactions, PML, and cutaneous malignancies, suggesting updates to the drug's label may be necessary. Physicians should monitor for neurological and skin changes in patients and discontinue treatment if PML is suspected. Moreover, the median onset time for bendamustine-associated AEs was 13 days, with an interquartile range [IQR] of 0-59 days, predominantly occurring on the first day post-initiation. The β of bendamustine-related AEs suggested risk reduction over time. Conclusion: Our study uncovered some potential pharmacovigilance signals for bendamustine, providing important insights for its safe and effective clinical use.

Management of relapsed/refractory mantle cell lymphoma

In this review we summarize the current evidence describing the management of patients with relapsed/refractory MCL and outline the various novel therapeutics that have been developed over the past two decades. We also describe how overall response rates, complete response rates, duration of responses, and life expectancy have dramatically increased with the introduction of novel therapies, particularly covalent Bruton Tyrosine Kinase inhibitors (BTKi) and chimeric antigen receptor T-cell (CAR-T) therapy. The most recent emerging options for patients with progressive disease following BTKi or CAR-T, including non-covalent BTKi, antibody-drug conjugates, Bcl-2 inhibitors, and bispecific antibodies, may further improve response rates and outcomes. Future directions should focus on identifying the best sequencing and/or combinations of the increasingly available treatment options while prioritizing strategies with curative potential.

Acute leukemias and complicated lymphomas: pearls to optimize management when patients stay local

Hematologic malignancies often present acutely with a constellation of infectious complications, pancytopenia, tumor lysis, and renal dysfunction. Acute leukemias and aggressive lymphomas often require hospitalization for rapid diagnostic evaluation, urgent management of complicating presentations, and timely management of intensive systemic therapies. There is an emerging paradigm whereby complex cancer care can be safely and effectively provided in the community, where the majority of cancer is treated. A substantive and effective network between local oncologists and their academic counterparts will enhance care for the patient, advance research, and help bring complicated therapies to local centers, thereby improving access. Here we present several cases that highlight a collaborative approach to complicated hematologic malignancies in the community.

Stem cell transplant for mantle cell lymphoma in Taiwan

Mantle cell lymphoma (MCL) is a B-cell lymphoma featuring an aggressive course and a progressive relapsing pattern. International guidelines recommend early consolidative autologous stem cell transplant (auto-SCT) for eligible patients while reserving allogeneic SCT (allo-SCT) as therapy for refractory cases. Since data describing the implementation of transplants in the Asian population with MCL are limited, we aimed to analyze post-SCT outcomes of 99 MCL patients from the Taiwan Bone Marrow Transplant Registry database. The median age was 56 years, and 11% of the patients had blastoid variant MCL. Ninety-four patients received auto-SCT, while 13 patients received allo-SCT, eight of which received allo-SCT after failing auto-SCT. Before auto-SCT, 52% of the patients were in their first complete remission (CR1). Overall, 37 patients (39%) relapsed after auto-SCT. The median post-auto-SCT progression-free survival and overall survival (OS) were 43.6 months and not reached, respectively. Blastoid variant MCL, transplant not received in CR1, and disease progression within 12 months post-auto-SCT independently predicted inferior OS in multivariable analysis. The median post-allo-SCT OS was 74 months. Two patients (15%) died of MCL recurrence post-allo-SCT. Three patients with refractory diseases were salvaged with ibrutinib or venetoclax to allo-SCT. Treatment strategies incorporating novel agents warrant further optimization.

Bendamustine-induced rash is associated with a favorable prognosis in patients with indolent B-cell lymphoma

Bendamustine is now recognized as a key drug for indolent B-cell lymphoma (iBCL), mantle cell lymphoma (MCL) and chronic lymphocytic leukemia (CLL). Skin toxicity associated with bendamustine is one of the characteristic adverse effects. We retrospectively examined the relationship between bendamustine-associated drug rashes and disease prognosis of iBCL and MCL at our institution. Between January 2011 and August 2019, 65 patients (39 men and 26 women, median age 68, range 41-84 years) were treated with bendamustine alone (n=11, 120 mg/m² on days 1 and 2) or a combination of rituximab and bendamustine (n=54, 90 mg/m² on days 1 and 2). Of these patients, 47 had follicular lymphoma (FL), 10 had MCL and 8 had other iBCLs. Drug rash occurred in 27 (41.5%). Eight cases (29.6%) were grade 1, 5 (18.5%) were grade 2 and 14 (51.9%) were grade 3. The onset was in the first course in 17 (63.0%), 2nd course in 5 (18.5%), 3rd course in 2 (7.4%), 4th course in 1 (3.7%) and 5th course in 2 (7.4%). No treatment was administered in 1 case (3.7%), topical steroid was applied in 10 (37.0%), antiallergic drug was administered in 2 (7.4%), topical steroid and antiallergic drug were administered in 5 (18.5%), and oral and topical steroid and antiallergic drug were administered in 9 (33.3%). The 3-year progression-free survival (PFS) and overall survival (OS) in patients with rash development were 80.0% and 85.5%, respectively, and those in patients without development were 36.4% and 54.0%, respectively (p=0.009 and 0.02, respectively). By multivariate analysis, the development of rash was associated with a better PFS and a diagnosis of iBCL was associated with a better OS. This study revealed that bendamustine-induced rash is associated with a favorable prognosis among patients with iBCL.

Current Knowledge in Genetics, Molecular Diagnostic Tools, and Treatments for Mantle Cell Lymphomas

Mantle Cell lymphoma (MCL) is a mature B-cell lymphoma with a well-known hallmark genetic alteration in most cases, t (11,14)(q13q32)/CCND1-IGH. However, our understanding of the genetic and epigenetic alterations in MCL has evolved over the years, and it is now known that translocations involving CCND2, or cryptic insertion of enhancer elements of IGK or IGL gene, can also lead to MCL. On a molecular level, MCL can be broadly classified into two subtypes, conventional MCL (cMCL) and non-nodal MCL (nnMCL), each with different postulated tumor cell origin, clinical presentation and behavior, mutational pattern as well as genomic complexity. This article reviews both the common and rare alterations in MCL on a gene mutational, chromosomal arm, and epigenetic level, in the context of their contribution to the lymphomagenesis and disease evolution in MCL. This article also summarizes the important prognostic factors, molecular diagnostic tools, and treatment options based on the most recent MCL literature.

PET/CT-Based Response Evaluation in Cancer-a Systematic Review of Design Issues

Positron emission tomography/x-ray computed tomography (PET/CT) has long been discussed as a promising modality for response evaluation in cancer. When designing respective clinical trials, several design issues have to be addressed, especially the number/timing of PET/CT scans, the approach for quantifying metabolic activity, and the final translation of measurements into a rule. It is unclear how well these issues have been tackled in quest of an optimised use of PET/CT in response evaluation. Medline via Ovid and Science Citation Index via Web of Science were systematically searched for articles from 2015 on cancer patients scanned with PET/CT before and during/after treatment. Reports were categorised as being either developmental or evaluative, i.e. focusing on either the establishment or the evaluation of a rule discriminating responders from non-responders. Of 124 included papers, 112 (90 %) were accuracy and/or prognostic studies; the remainder were response-curve studies. No randomised controlled trials were found. Most studies were prospective (62 %) and from single centres (85 %); median number of patients was 38.5 (range 5-354). Most (69 %) of the studies employed only one post-baseline scan. Quantification was mainly based on SUVmax (91 %), while change over time was most frequently used to combine measurements into a rule (79 %). Half of the reports were categorised as developmental, the other half evaluative. Most development studies assessed only one element (35/62, 56 %), most frequently the choice of cut-off points (25/62, 40 %). In summary, the majority of studies did not address the essential open issues in establishing PET/CT for response evaluation. Reasonably sized multicentre studies are needed to systematically compare the many different options when using PET/CT for response evaluation.

Outcomes in first relapsed-refractory younger patients with mantle cell lymphoma: results from the MANTLE-FIRST study

Patients with mantle cell lymphoma (MCL) that fail induction treatment represent a difficult-to-treat population, where no standard therapy exists. We evaluated outcomes in patients with first relapsed-refractory (r/r) MCL after upfront high dose cytarabine including standard regimens. Overall survival (OS-2) and progression-free survival (PFS-2) were estimated from the time of salvage therapy. The previously described threshold of 24 months was used to define patients as early- or late-progressors (POD). Overall, 261 r/r MCL patients were included. Second-line regimens consisted of rituximab-bendamustine (R-B, 21%), R-B and cytarabine (R-BAC, 29%), ibrutinib (19%), and others (31%). The four groups were balanced in terms of clinicopathological features. Adjusting for age and early/late-POD, patients treated with R-BAC had significantly higher complete remission (63%) than comparators. Overall, Ibrutinib and R-BAC were associated with improved median PFS-2 [24 and 25 months, respectively], compared to R-B (13) or others (7). In patients with early-POD (n = 127), ibrutinib was associated with inferior risk of death than comparators (HR 2.41 for R-B, 2.17 for others, 2.78 for R-BAC). In patients with late-POD (n = 134), no significant differences were observed between ibrutinib and bendamustine-based treatments. Ibrutinib was associated with improved outcome in early-POD patients.

Correlative analysis of overall survival with clinical characteristics in 127 patients with mantle cell lymphoma: a multi-institutional cohort in Taiwan

Mantle cell lymphoma (MCL) is a B-cell non-Hodgkin lymphoma often with extranodal involvement at diagnosis, and yet how this feature correlates with survival awaits elucidation. To address this issue, a correlative analysis between clinical features of 127 MCL patients and their overall survival (OS) was conducted. In this cohort, the median age at MCL diagnosis was 62 years and 81% were males. Eighty-four percent of patients were Ann Arbor stage 4, and 15% were blastoid variants. In patients with gastrointestinal MCL, approximately 40% had gastric involvement. In treatment, CHOP-based induction chemotherapy was given to 61.1% of patients. One-third of patients undertook autologous stem cell transplant (SCT), and 4.7% had allogeneic SCT. The median OS was 82 months and well-stratified in MIPI risk groups. In the multivariate analysis for OS, blastoid variants and gastric involvement were both independent risk factors whereas auto-SCT had a protective effect. Overall, this study corroborated with the current understandings and international therapeutic standards for MCL. Auto-SCT associated with a better OS while allo-SCT remained an option for blastoid variants and those who failed Auto-SCT. Interestingly, patients with gastric involvement tended to have worse survival, a finding that spawns more studies to investigate the mechanism.

18F-FDG PET or PET/CT in Mantle Cell Lymphoma

The aim of this systematic review was to examine published data about the potential role of Fluorine-18-fluorodeoxyglucose positron emission tomography or positron emission tomography/computed tomography (¹⁸F-FDG PET or PET/CT) in patients affected by mantle cell lymphoma (MCL). A comprehensive computer literature search of Scopus, PubMed/MEDLINE, and Embase databases was conducted, including articles indexed up to November, 2019; 25 studies or subsets in studies analyzing the value of ¹⁸F-FDG PET or PET/CT in patients with MCL were eligible for inclusion. From the analyses of the selected studies, the following main findings are described: (1) MCL are ¹⁸F-FDG-avid in most of cases, especially nodal lesions, but bone marrow and gastrointestinal disease localizations have low ¹⁸F-FDG avidity; (2) ¹⁸F-FDG PET/CT seems to be helpful in staging setting, showing a better diagnostic performance than conventional imaging and a positive impact on clinical stage; (3) ¹⁸F-FDG PET/CT is useful in evaluating treatment response, especially after chemotherapy and transplantation; and (4) metabolic response after therapy seems to have a prognostic role. Despite several limitations affecting this analysis, especially related to the heterogeneity of the studies included, MCL is an ¹⁸F-FDG-avid lymphoma in most of the cases, with the exception of bone marrow and gastrointestinal disease. Moreover, ¹⁸F-FDG PET/CT seems to be useful in evaluating treatment response and prognosis.

Bendamustine-EAM versus BEAM regimen in patients with mantle cell lymphoma undergoing autologous stem cell transplantation in the frontline setting: a multicenter retrospective study from Lymphoma Study Association (LYSA) centers

The combination of carmustine, etoposide, cytarabine, and melphalan (BEAM) as conditioning regimen prior to autologous stem-cell transplantation (ASCT) remains the standard of care for patients with mantle cell lymphoma (MCL) who are eligible for transplantation. The replacement of carmustine with bendamustine (BeEAM) was described as a promising alternative in non-Hodgkin lymphoma. The aim of this retrospective study was to compare the BeEAM with the BEAM regimen in MCL patients in the frontline setting. Sixty and 108 patients were included in the BeEAM and the BEAM groups, respectively. At 3 years, progression-free survival (PFS) was significantly higher in the BeEAM than in the BEAM group (84% [73-96] vs. 63% [51-79], p = 0.03). The overall survival was not statistically different between the two groups (p = 0.2). In multivariable analysis, BeEAM regimen remained associated with higher PFS (HR = 0.377, 95% CI, 0.146-0.970; p = 0.043). Subgroup analyses in patients treated with prior rituximab-aracytine induction alone showed that BeEAM improved the PFS compared with BEAM regimen (p = 0.04). Despite the high rate of acute renal failure KDIGO III (32%), treatment-related mortality was not increased with the BeEAM regimen. A prospective randomized trial will be necessary to confirm the beneficial effect of the BeEAM regimen in MCL patients undergoing ASCT.

The Role of 18F-FDG PET/CT in Staging and Prognostication of Mantle Cell Lymphoma: An Italian Multicentric Study

Mantle cell lymphoma (MCL) is an aggressive lymphoma subtype with poor prognosis in which 18F-FDG-PET/CT role in treatment response evaluation and prediction of outcome is still unclear. The aim of this multicentric study was to investigate the role of 18F-FDG-PET/CT in staging MCL and the prognostic role of Deauville criteria (DC) in terms of progression-free survival (PFS) and overall survival (OS). We retrospectively enrolled 229 patients who underwent baseline and end-of-treatment (eot) 18F-FDG-PET/CT after first-line therapy. EotPET/CT scans were visually interpreted according to DC. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of PET/CT for evaluation of bone marrow (BM) were 27%, 100%, 100%, 48% and 57%, respectively. The sensitivity, specificity, positive predictive value, negative predictive value and accuracy of PET/CT for evaluation of the gastrointestinal (GI) tract were 60%, 99%, 93%, 90% and 91%, respectively. At a median follow-up of 40 months, relapse occurred in 104 cases and death in 49. EotPET/CT results using DC significantly correlated with PFS, not with OS. Instead, considering OS, only MIPI score was significantly correlated. In conclusion, we demonstrated that MCL is an FDG-avid lymphoma and 18F-FDG-PET/CT is a useful tool for staging purpose, showing good specificity for BM and GI evaluation, but suboptimal sensitivity. EotPET/CT result was the only independent significant prognostic factor that correlated with PFS.

Matching-adjusted Indirect Comparisons of the Efficacy and Safety of Acalabrutinib Versus Other Targeted Therapies in Relapsed/Refractory Mantle Cell Lymphoma

PURPOSE

Mantle cell lymphoma (MCL) is a rare subtype of B-cell non-Hodgkin lymphoma that can be either aggressive or indolent. Although MCL usually responds well to initial treatment with chemotherapy-based regimens, the disease often relapses or becomes refractory within a few years. Acalabrutinib is a highly selective, potent, covalent Bruton tyrosine kinase inhibitor with minimal off-target activity. WIthout head-to-head clinical trial data, estimation of the comparative efficacy and safety of new therapeutic entities provides valuable information for patients, clinicians, and health care payers. The objective of this analysis was to compare the efficacy and safety of acalabrutinib versus other targeted therapies employed for the treatment of relapsed/refractory MCL by using matching-adjusted indirect comparisons.

METHODS

Individual data from 124 patients treated with acalabrutinib in the Phase II ACE-LY-004 trial were adjusted to match average baseline characteristics of populations from studies using alternative targeted treatment regimens for relapsed/refractory MCL (for monotherapy: ibrutinib, bortezomib, lenalidomide, and temsirolimus; for combination therapies: ibrutinib + rituximab, bendamustine + rituximab, and lenalidomide + rituximab). Patient populations were matched on age, sex, race, Eastern Cooperative Oncology Group performance status, Simplified MCL International Prognostic Index score, tumor bulk, lactate dehydrogenase concentration, extranodal disease, bone marrow involvement, and number of previous treatment regimens. Outcomes assessed included overall response rate (ORR), complete response (CR) rate, overall survival (OS), progression-free survival (PFS), and adverse events.

FINDINGS

After matching, acalabrutinib was associated with significant increases in ORR and CR rate (estimated treatment difference [95% CI]) versus ibrutinib (ORR, 9.3% [0.3-18.3]; CR, 14.9% [5.4-24.3]), bortezomib (ORR, 50.6% [40.2-61.0]; CR, 18.8% [9.1-28.5]), lenalidomide (ORR, 38.1% [27.1-49.1]; CR, 43.5% [34.8-52.3]), and temsirolimus (ORR, 40.7% [31.0-50.4]; CR, 27.1% [19.2-35.0]). PFS (hazard ratio [95% CI]) with acalabrutinib was significantly increased versus bortezomib (0.36 [0.26-0.51]), lenalidomide (0.65 [0.48-0.89]), lenalidomide + rituximab (0.57 [0.35-0.93]), and temsirolimus (0.33 [0.24-0.45]). Acalabrutinib was associated with significantly increased OS (hazard ratio) versus bortezomib (0.36 [0.22-0.61]) and temsirolimus (0.32 [0.23-0.44]). The overall safety profile of acalabrutinib was similar or better compared with the monotherapies; however, infection risk increased versus bendamustine + rituximab, and anemia increased risk versus lenalidomide + rituximab and ibrutinib + rituximab.

IMPLICATIONS

This comparison of targeted therapies used in the treatment of relapsed/refractory MCL showed that acalabrutinib has the potential to provide increased response rates, with trends for increased PFS and OS, and an improved safety profile.

Adverse events, resource use, and economic burden associated with mantle cell lymphoma: a real-world assessment of privately insured patients in the United States

In view of recent therapeutic advances in mantle cell lymphoma (MCL), the aim of this retrospective cohort analysis was to assess treatment patterns, adverse events (AEs), resource utilization, and health care costs in patients with MCL in a US-based commercial claims database. A total of 783 patients with MCL (median age = 65 years) were selected. Among patients receiving systemic therapy (n = 457), the most common treatment regimens were bendamustine/rituximab (BR) (41.1%), rituximab/cyclophosphamide/doxorubicin/vincristine (RCHOP) (26.7%), rituximab monotherapy (20.4%), and ibrutinib monotherapy (14.2%). Mean monthly costs during treatments with BR, RCHOP, rituximab, and ibrutinib were $12,958, $24,719, $13,153, and $21,690, respectively. Mean monthly cost during follow-up was $13,650 among patients with ≥6 AEs versus $5131 among those without AEs. The costs of MCL varied considerably by treatment regimen and care setting. The overall economic burden of managing patients with MCL can be substantially affected by costs associated with managing AEs occurring during treatment.

First-Line Treatment of Patients With Indolent Non-Hodgkin Lymphoma or Mantle-Cell Lymphoma With Bendamustine Plus Rituximab Versus R-CHOP or R-CVP: Results of the BRIGHT 5-Year Follow-Up Study

PURPOSE

The BRIGHT study ( ClinicalTrials.gov identifier: NCT00877006) was initiated to compare the efficacy and safety of bendamustine plus rituximab (BR) with either rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) or rituximab plus cyclophosphamide, vincristine, and prednisone (R-CVP) for treatment-naive patients with indolent non-Hodgkin lymphoma or mantle-cell lymphoma. This publication provides long-term follow-up data.

PATIENTS AND METHODS

Patients were monitored for a minimum of 5 years after completion of study treatment for the time-to-event end points of progression-free survival (PFS), event-free survival, duration of response, and overall survival per investigator assessment. Data on the number of patients who received second-line anticancer treatment and the occurrence of other malignancies were also collected.

RESULTS

The medians were not reached for any of the time-to event end points for either the BR or R-CHOP/R-CVP study treatment groups by study completion. PFS rates at 5 years were 65.5% in the BR treatment group and 55.8% in the R-CHOP/R-CVP group. The difference in PFS was considered significant with a hazard ratio of 0.61 (95% CI, 0.45 to 0.85; P = .0025). The hazard ratio for event-free survival and duration of response (P = .0020 and .0134, respectively) also favored the BR regimen over R-CHOP/R-CVP. However, no significant difference in overall survival was observed. The overall safety profiles of BR, R-CHOP, and R-CVP were as expected; no new safety data were collected during long-term follow-up. A higher number of secondary malignancies was noted in the BR treatment group.

CONCLUSION

Overall, BR demonstrated better long-term disease control than R-CHOP/R-CVP and should be considered as a first-line treatment option for patients with indolent and mantle-cell lymphoma.

Study of gene polymorphisms as predictors of treatment efficacy and toxicity in patients with indolent non-hodgkin lymphomas and mantle cell lymphoma receiving bendamustine and rituximab

Bendamustine is used in combination with rituximab (BR) to treat indolent non-Hodgkin lymphomas (iNHL) and mantle cell lymphoma (MCL). The variability in treatment efficacy and toxicity could be related to single nucleotide polymorphisms (SNPs) in immune response genes. We would like to show a correlation between SNPs and treatment outcome in iNHL and MCL patients receiving BR. We investigated some SNPs that had already been associated with NHL outcome. Samples were genotyped for the IL2 (rs2069762), IL10 (rs1800890, rs10494879), VEGFA (rs3025039), IL8 (rs4073), CFH (rs1065489) and MTHFR (rs1801131) SNPs by allelic discrimination assays. We enrolled 70 patients that received rituximab 375 mg/m² and bendamustine 90 mg/m² every 28 days, both as first-line treatment and ≥ second-line regimens. Overall response rate was 97·1% (complete response [CR] rate 73·9%). Treatment toxicity included grade 3-4 neutropenia (24/70 patients), infections (21/70 patients; 1/70 grade 3), skin rash (26/70 patients; 2/70 grade 3). After a median follow-up of 24 months we did find any correlation between the analysed SNPs, CR rate and PFS. However, we demonstrated an association between the SNP in IL2 (rs2069762) and the onset of skin rash (P = 0·0001). Our study suggests a role for cytokine SNPs in bendamustine-related toxicity, which could represent a promising research field.

Pseudo-autologous stem cell transplantation for donor-derived mantle cell lymphoma 12 years after allogeneic transplantation

Donor-derived malignancy is a rare morbidity after allogeneic hematopoietic stem cell transplantation (HSCT), in which most previous cases have presented as acute leukemia or myelodysplastic syndrome. There have, however, been very few reports of donor-derived lymphoma. Here, we present a case of donor-derived mantle cell lymphoma 12 years after allogeneic HSCT, which was successfully treated with chemotherapy followed by pseudo-autologous HSCT (pASCT), i.e., an autologous HSC transplant following allogeneic HSCT in which the infused stem cell is considered to be derived from the donor cells. Although pASCT carries the risk of graft-versus-host disease (GVHD) due to the reinfusion of donor-derived peripheral blood cells, the present case did not develop GVHD without prophylaxis. The current case and a small number of previous reports suggest that the duration between allogeneic HSCT and pASCT may be important to the induction of immune tolerance, but further study in a larger number of cases is needed.

The PARP Inhibitor Veliparib Can Be Safely Added to Bendamustine and Rituximab and Has Preliminary Evidence of Activity in B-Cell Lymphoma

Purpose: The PARP inhibitor veliparib enhances the cytotoxicity of alkylating agents. This phase I study evaluated veliparib with the bifunctional alkylator bendamustine (VB) in patients with relapsed/refractory lymphoma, multiple myeloma, and solid malignancies, with a cohort expansion of VB with rituximab (VBR) in patients with B-cell lymphomas.Experimental Design: This dose-escalation study evaluated safety, pharmacokinetics, and preliminary efficacy of veliparib (20-400 mg twice a day, days 1-7 of 28-day cycle) and bendamustine (70 and 90 mg/m² intravenously, days 1 and 2). A cohort expansion was conducted, which combined veliparib and bendamustine at the maximum tolerated dose (MTD) with rituximab (375 mg/m², day 1) in patients with B-cell lymphomas. Thirty-four patients were treated in seven dose-escalation cohorts and seven patients in the dose-expansion cohort.Results: The MTD was veliparib 300 mg twice daily plus bendamustine 90 mg/m² Dose-limiting toxicities (DLT) were anemia, nausea, hypertension, and hyperhidrosis. Grade ≥3 toxicities included lymphopenia (87.8%), anemia (19.5%), neutropenia (12.2%), thrombocytopenia (9.8%), leukopenia (9.8%), nausea (7.3%), and hypophosphatemia (7.3%). Apparent veliparib clearance was slightly lower than previously reported. Of 14 patients with lymphoma evaluable for response, five of seven (71%) on VB and six of seven (86%) on VBR achieved objective response. One patient with multiple myeloma achieved partial response.Conclusions: VB and VBR were generally well-tolerated. VBR had preliminary clinical activity in patients with B-cell lymphoma, which warrants further investigation in a phase II trial. This trial was registered at www.clinicaltrials.gov as NCT01326702 Clin Cancer Res; 23(15); 4119-26. ©2017 AACR.