Rituximab as adjuvant to high-dose therapy and autologous hematopoietic cell transplantation for aggressive non-Hodgkin lymphoma

Cisplatin as a Viable and Secure Alternative to Carmustine in BEAM-Based Conditioning for Autologous Hematopoietic Stem Cell Transplantation in Patients with Lymphoma

BACKGROUND

High-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (auto-HSCT) is a standard treatment for relapsed/refractory lymphoma patients. Yet, the widespread use of BEAM is hindered by carmustine accessibility. This study evaluates the efficacy and safety of PEAM (Cisplatin, Etoposide, Cytarabine, and Melphalan) versus BEAM in auto-HSCT for Hodgkin (HL) and non-Hodgkin lymphoma (NHL) patients.

METHODS

We conducted a retrospective single-center study of adult lymphoma patients who received PEAM or BEAM pretransplant conditioning between January 2004 to December 2022, comparing efficacy and safety outcomes.

RESULTS

Among 143 patients (median age of 33 years, 58% males), 55 had HL, and 88 had NHL. The overall response rate (ORR) was 86.7% for PEAM and 72.3% for BEAM, and the relapse rate (RR) was lower for PEAM than BEAM (22.9% vs 45.6%). Median time to relapse (TTR) and overall survival (OS) were not reached for either group. PEAM exhibited a shorter time to both neutrophil (NE) and platelet (PE) engraftment compared to BEAM (10 vs 12 days), with a more tolerable gastrointestinal (GI) toxicity profile.

CONCLUSIONS

Both BEAM and PEAM showed similar outcomes, demonstrating comparable efficacy in terms of ORR, TTR, and OS for both HL and NHL patients. However, PEAM-conditioning was associated with a shorter time to engraftment and fewer GI adverse events.

Management of vaccinations in patients with non-Hodgkin lymphoma

Vaccinations are fundamental tools in preventing infectious diseases, especially in immunocompromised patients like those affected by non-Hodgkin lymphomas (NHLs). The COVID-19 pandemic made clinicians increasingly aware of the importance of vaccinations in preventing potential life-threatening SARS-CoV-2-related complications in NHL patients. However, several studies have confirmed a significant reduction in vaccine-induced immune responses after anti-CD20 monoclonal antibody treatment, thus underscoring the need for refined immunization strategies in NHL patients. In this review, we summarize the existing data about COVID-19 and other vaccine's efficacy in patients with NHL and propose multidisciplinary team-based recommendations for the management of vaccines in this specific group of patients.

An inducible Cd79b mutation confers ibrutinib sensitivity in mouse models of Myd88-driven diffuse large B-cell lymphoma

ABSTRACT

Diffuse large B-cell lymphoma (DLBCL) is the most common aggressive lymphoma and constitutes a highly heterogenous disease. Recent comprehensive genomic profiling revealed the identity of numerous molecularly defined DLBCL subtypes, including a cluster which is characterized by recurrent aberrations in MYD88, CD79B, and BCL2, as well as various lesions promoting a block in plasma cell differentiation, including PRDM1, TBL1XR1, and SPIB. Here, we generated a series of autochthonous mouse models to mimic this DLBCL cluster and specifically focused on the impact of Cd79b mutations in this setting. We show that canonical Cd79b immunoreceptor tyrosine-based activation motif (ITAM) mutations do not accelerate Myd88- and BCL2-driven lymphomagenesis. Cd79b-mutant murine DLBCL were enriched for IgM surface expression, reminiscent of their human counterparts. Moreover, Cd79b-mutant lymphomas displayed a robust formation of cytoplasmic signaling complexes involving MYD88, CD79B, MALT1, and BTK. These complexes were disrupted upon pharmacological BTK inhibition. The BTK inhibitor-mediated disruption of these signaling complexes translated into a selective ibrutinib sensitivity of lymphomas harboring combined Cd79b and Myd88 mutations. Altogether, this in-depth cross-species comparison provides a framework for the development of molecularly targeted therapeutic intervention strategies in DLBCL.

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

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

Vaccinations in hematological patients in the era of target therapies: Lesson learnt from SARS-CoV-2

Novel targeting agents for hematologic diseases often exert on- or off-target immunomodulatory effects, possibly impacting on response to anti-SARS-CoV-2 vaccinations and other vaccines. Agents that primarily affect B cells, particularly anti-CD20 monoclonal antibodies (MoAbs), Bruton tyrosine kinase inhibitors, and anti-CD19 chimeric antigen T-cells, have the strongest impact on seroconversion. JAK2, BCL-2 inhibitors and hypomethylating agents may hamper immunity but show a less prominent effect on humoral response to vaccines. Conversely, vaccine efficacy seems not impaired by anti-myeloma agents such as proteasome inhibitors and immunomodulatory agents, although lower seroconversion rates are observed with anti-CD38 and anti-BCMA MoAbs. Complement inhibitors for complement-mediated hematologic diseases and immunosuppressants used in aplastic anemia do not generally affect seroconversion rate, but the extent of the immune response is reduced under steroids or anti-thymocyte globulin. Vaccination is recommended prior to treatment or as far as possible from anti-CD20 MoAb (at least 6 months). No clearcut indications for interrupting continuous treatment emerged, and booster doses significantly improved seroconversion. Cellular immune response appeared preserved in several settings.

Distinct Genetically Determined Origins of Myd88/BCL2-Driven Aggressive Lymphoma Rationalize Targeted Therapeutic Intervention Strategies

Genomic profiling revealed the identity of at least 5 subtypes of diffuse large B-cell lymphoma (DLBCL), including the MCD/C5 cluster characterized by aberrations in MYD88, BCL2, PRDM1, and/or SPIB. We generated mouse models harboring B cell-specific Prdm1 or Spib aberrations on the background of oncogenic Myd88 and Bcl2 lesions. We deployed whole-exome sequencing, transcriptome, flow-cytometry, and mass cytometry analyses to demonstrate that Prdm1- or Spib-altered lymphomas display molecular features consistent with prememory B cells and light-zone B cells, whereas lymphomas lacking these alterations were enriched for late light-zone and plasmablast-associated gene sets. Consistent with the phenotypic evidence for increased B cell receptor signaling activity in Prdm1-altered lymphomas, we demonstrate that combined BTK/BCL2 inhibition displays therapeutic activity in mice and in five of six relapsed/refractory DLBCL patients. Moreover, Prdm1-altered lymphomas were immunogenic upon transplantation into immuno-competent hosts, displayed an actionable PD-L1 surface expression, and were sensitive to antimurine-CD19-CAR-T cell therapy, in vivo.

SIGNIFICANCE

Relapsed/refractory DLBCL remains a major medical challenge, and most of these patients succumb to their disease. Here, we generated mouse models, faithfully recapitulating the biology of MYD88-driven human DLBCL. These models revealed robust preclinical activity of combined BTK/BCL2 inhibition. We confirmed activity of this regimen in pretreated non-GCB-DLBCL patients. See related commentary by Leveille et al., p. 8. This article is highlighted in the In This Issue feature, p. 1.

Secondary rituximab-associated versus primary immunodeficiencies: The enigmatic border

Rituximab (RTX), a chimeric monoclonal antibody targeting CD20-positive cells, is a valuable treatment option for malignant and benign immune-related disorders. The rationale of targeting the CD20 antigen relies on depletion of both healthy and autoreactive/malignant CD20-espressing cells, but normal B-cell reconstitution is expected within months after treatment. Nevertheless, a number of recent studies have documented prolonged B-cell deficiency associated with new-onset hypogammaglobulinemia in patients receiving RTX. Awareness of post-RTX hypogammaglobulinemia has become wider among clinicians, with a growing number of reports about the increased incidence, especially in children. Although these patients were previously regarded as affected by secondary/iatrogenic immunodeficiency, atypical clinical and immunological manifestations (e.g., severe or opportunistic infections; prolonged B-cell aplasia) raise concerns of delayed manifestations of genetic immunological disorders that have been unveiled by B-cell perturbation. As more patients with undiagnosed primary immune deficiency receiving RTX have been identified, it remains the challenge in discerning those that might display a higher risk of persistent RTX-associated hypogammaglobulinemia and need a tailored immunology follow-up. In this review, we summarize the principal evidence regarding post-RTX hypogammaglobulinemia and provide a guideline for identifying patients at higher risk of RTX-associated hypogammaglobulinemia that could harbor an inborn error of immunity.

Late onset neutropenia after rituximab and obinutuzumab treatment - characteristics of a class-effect toxicity

Late onset neutropenia (LON) after rituximab is a previously described complication. We aimed to assess and characterize LON after obinutuzumab, a novel anti-CD20 antibody, in the real-world setting and compare it to LON after rituximab therapy. We retrospectively analyzed 330 consecutive patients with lymphoproliferative neoplasms (rituximab-treated n = 283; obinutuzumab-treated n = 47). LON occurred in 23% patients with similar incidence in rituximab (n = 66, 23%) or obinutuzumab (n = 10, 21%) groups (p = 0.853). Patients treated for CLL and post-transplantation lymphoproliferative disease (PTLD) were at higher risk to develop LON (multivariate analysis: HR for CLL - 6.62 CI 95% 1.33-32.92; HR for PTLD 15.82 CI 95% 2.04-122.4). Febrile neutropenia was uncommon during LON and occurred in 15 patients (4.5%; rituximab (n = 14) and obinutuzumab (n = 1).These data suggest that LON after obinutuzumab treatment is as common as with rituximab. The similarities in LON after rituximab and obinutuzumab argue for a possible class effect for anti-CD20 monoclonal antibodies.

Vaccine response following anti-CD20 therapy: a systematic review and meta-analysis of 905 patients

The objective of this study was to perform a systematic review of the literature on vaccine responsiveness in patients who have received anti-CD20 therapy. PubMed and EMBASE were searched up to 4 January 2021 to identify studies of vaccine immunogenicity in patients treated with anti-CD20 therapy, including patients with hematologic malignancy or autoimmune disease. The primary outcomes were seroprotection (SP), seroconversion (SC), and/or seroresponse rates for each type of vaccine reported. As the pandemic influenza vaccine (2009 H1N1) has standardized definitions for SP and SC, and represented a novel primary antigen similar to the COVID-19 vaccine, meta-analysis was conducted for SC of studies of this vaccine. Pooled estimates, relative benefit ratios (RBs), and 95% confidence intervals (CIs) were calculated using a random-effects model. Thirty-eight studies (905 patients treated with anti-CD20 therapy) were included (19 studies of patients with hematologic malignancies). Patients on active (<3 months since last dose) anti-CD20 therapy had poor responses to all types of vaccines. The pooled estimate for SC after 1 pandemic influenza vaccine dose in these patients was 3% (95% CI, 0% to 9%), with an RB of 0.05 (95% CI, 0-0.73) compared with healthy controls and 0.22 (95% CI, 0.09-0.56) compared with disease controls. SC compared with controls seems abrogated for at least 6 months following treatment (3-6 months post anti-CD20 therapy with an RB of 0.50 [95% CI, 0.24-1.06] compared with healthy and of 0.44 [95% CI, 0.23-0.84] compared with disease controls). For all vaccine types, response to vaccination improves incrementally over time, but may not reach the level of healthy controls even 12 months after therapy.

Efficacy of the BNT162b2 mRNA COVID-19 vaccine in patients with chronic lymphocytic leukemia

Patients with chronic lymphocytic leukemia (CLL) have an increased risk for severe COVID-19 disease and mortality. The goal of this study was to determine the efficacy of COVID-19 vaccine in patients with CLL. We evaluated humoral immune responses to the BNT162b2 messenger RNA (mRNA) COVID-19 vaccine in patients with CLL and compared responses with those obtained in age-matched healthy control subjects. Patients received 2 vaccine doses, 21 days apart, and antibody titers were measured by using the Elecsys Anti-SARS-CoV-2 S assay after administration of the second dose. In a total of 167 patients with CLL, the antibody response rate was 39.5%. A comparison between 52 patients with CLL and 52 sex- and aged-matched healthy control subjects revealed a significantly reduced response rate among patients (52% vs 100%, respectively; adjusted odds ratio, 0.010; 95% confidence interval, 0.001-0.162; P < .001). The response rate was highest in patients who obtained clinical remission after treatment (79.2%), followed by 55.2% in treatment-naive patients and 16.0% in patients under treatment at the time of vaccination. In patients treated with either Bruton's tyrosine kinase inhibitors or venetoclax ± anti-CD20 antibody, response rates were considerably low (16.0% and 13.6%). None of the patients exposed to anti-CD20 antibodies <12 months before vaccination responded. In a multivariate analysis, the independent predictors of response were younger age, female sex, lack of currently active treatment, immunoglobulin G levels ≥550 mg/dL, and immunoglobulin M levels ≥40 mg/dL. In conclusion, antibody-mediated response to the BNT162b2 mRNA COVID-19 vaccine in patients with CLL is markedly impaired and affected by disease activity and treatment. This trial was registered at www.clinicaltrials.gov as #NCT04746092.

Pneumococcal Vaccination in Immunocompromised Hosts: An Update

Infections with the pathogen, Streptococcus pneumoniae, are a common cause of morbidity and mortality worldwide. It particularly affects those at the extremes of age and immunocompromised individuals. Preventing pneumococcal disease is paramount in at risk individuals, and pneumococcal vaccination should be offered. Here, we discuss the role of pneumococcal vaccination in specific groups of immunocompromised hosts.

Acute Immune Signatures and Their Legacies in Severe Acute Respiratory Syndrome Coronavirus-2 Infected Cancer Patients

Given the immune system's importance for cancer surveillance and treatment, we have investigated how it may be affected by SARS-CoV-2 infection of cancer patients. Across some heterogeneity in tumor type, stage, and treatment, virus-exposed solid cancer patients display a dominant impact of SARS-CoV-2, apparent from the resemblance of their immune signatures to those for COVID-19+ non-cancer patients. This is not the case for hematological malignancies, with virus-exposed patients collectively displaying heterogeneous humoral responses, an exhausted T cell phenotype and a high prevalence of prolonged virus shedding. Furthermore, while recovered solid cancer patients' immunophenotypes resemble those of non-virus-exposed cancer patients, recovered hematological cancer patients display distinct, lingering immunological legacies. Thus, while solid cancer patients, including those with advanced disease, seem no more at risk of SARS-CoV-2-associated immune dysregulation than the general population, hematological cancer patients show complex immunological consequences of SARS-CoV-2 exposure that might usefully inform their care.

An Autochthonous Mouse Model of Myd88- and BCL2-Driven Diffuse Large B-cell Lymphoma Reveals Actionable Molecular Vulnerabilities

Based on gene expression profiles, diffuse large B cell lymphoma (DLBCL) is sub-divided into germinal center B cell-like (GCB) and activated B cell-like (ABC) DLBCL. Two of the most common genomic aberrations in ABC-DLBCL are mutations in MYD88, as well as BCL2 copy number gains. Here, we employ immune phenotyping, RNA-Seq and whole exome sequencing to characterize a Myd88 and Bcl2-driven mouse model of ABC-DLBCL. We show that this model resembles features of human ABC-DLBCL. We further demonstrate an actionable dependence of our murine ABC-DLBCL model on BCL2. This BCL2 dependence was also detectable in human ABC-DLBCL cell lines. Moreover, human ABC-DLBCLs displayed increased PD-L1 expression, compared to GCB-DLBCL. In vivo experiments in our ABC-DLBCL model showed that combined venetoclax and RMP1-14 significantly increased the overall survival of lymphoma bearing animals, indicating that this combination may be a viable option for selected human ABC-DLBCL cases harboring MYD88 and BCL2 aberrations.

New murine models of aggressive lymphoma

Diffuse large B cell lymphoma (DLBCL) is the most common type of aggressive lymphoma and has traditionally been subdivided into germinal center B cell-like and activated B cell-like DLBCL, using transcriptome profiling. The recent characterization of the genomic landscape of DLBCL revealed the identity of at least five molecularly-defined subclusters of DLBCL. Intriguingly, these different clusters display a different response to frontline, anthracycline-based chemo-immune therapy. Moreover, multiple, potentially actionable genomic aberrations have been identified in these clusters, including EZH2, CREBBP/EP300, and KMT2D mutations, BCL2 overexpression, PTEN inactivation, CD274 rearrangements and others. With this genomic understanding, it is possible to develop autochthonous mouse models, which capture this genomic complexity. These models can serve as pre-clinical platforms to devise molecularly targeted therapeutic intervention strategies. Here, we review the available mouse models of aggressive lymphoma and indicate which compound-mutant mice may be desirable tools to further advance the field of translational lymphoma research.

Vaccination of haemopoietic stem cell transplant recipients: guidelines of the 2017 European Conference on Infections in Leukaemia (ECIL 7)

Infection is a main concern after haemopoietic stem cell transplantation (HSCT) and a major cause of transplant-related mortality. Some of these infections are preventable by vaccination. Most HSCT recipients lose their immunity to various pathogens as soon as the first months after transplant, irrespective of the pre-transplant donor or recipient vaccinations. Vaccination with inactivated vaccines is safe after transplantation and is an effective way to reinstate protection from various pathogens (eg, influenza virus and Streptococcus pneumoniae), especially for pathogens whose risk of infection is increased by the transplant procedure. The response to vaccines in patients with transplants is usually lower than that in healthy individuals of the same age during the first months or years after transplant, but it improves over time to become close to normal 2-3 years after the procedure. However, because immunogenic vaccines have been found to induce a response in a substantial proportion of the patients as early as 3 months after transplant, we recommend to start crucial vaccinations with inactivated vaccines from 3 months after transplant, irrespectively of whether the patient has or has not developed graft-versus-host disease (GvHD) or received immunosuppressants. Patients with GvHD have higher risk of infection and are likely to benefit from vaccination. Another challenge is to provide HSCT recipients the same level of vaccine protection as healthy individuals of the same age in a given country. The use of live attenuated vaccines should be limited to specific situations because of the risk of vaccine-induced disease.

Characteristics of pulmonary complications in non-Hodgkin's lymphoma patients treated with rituximab-containing chemotherapy and impact on survival

Patients with non-Hodgkin’s lymphoma (NHL) receiving rituximab-containing chemotherapy are at risk of developing respiratory complications, but comprehensive information on these complications and their impact on survival is lacking. We performed a retrospective cohort analysis on 123 NHL patients who received rituximab-containing chemotherapy between 2009 and 2016 in order to describe the incidence, etiologies and effect on survival of respiratory complications defined by new or worsening respiratory symptoms requiring diagnostic work-up or hospitalization. Thirty patients (24%) developed respiratory complications during a follow-up time of 825 (555–1338) days after chemotherapy. They had a higher prevalence of congestive heart failure and lung or pleural involvement at diagnosis as compared to patients who did not develop complications. Overall, 58 episodes of pulmonary complications were observed after median (interquartile) times from the first and last rituximab doses of 205 (75–580) days and 27 (14–163) days respectively. Infectious etiologies accounted for 75% of the respiratory complications, followed by heart failure exacerbation, lymphomatous involvement, and ARDS. Two Pneumocystis jirovecii pneumonias were observed, and no complication was ascribed to rituximab toxicity. Respiratory complications required ICU admission in 19 cases (33%) and invasive mechanical ventilation in 14 cases (24%). Using a time-dependent Cox regression analysis, we observed that the occurrence of respiratory complications was associated with a 170% increase in death hazard (hazard ratio 2.65, 95% CI 1.60–4.40, p = 0.001). In conclusion, respiratory complications in NHL patients receiving chemotherapy are relatively frequent, severe, and mostly infectious and are associated with increased mortality.

Clinical and microbiological characteristics of the infections in patients treated with rituximab for autoimmune and/or malignant hematological disorders

INTRODUCTION

Rituximab is commonly used for the treatment of hematological malignancies and autoimmune diseases. Despite a reputation for good tolerance, case-series and registries reported rituximab-related infections of variable severity including opportunistic infections. We aimed at describing the natural history of infectious events (IE) after treatment by rituximab providing clinical and microbiological features and outcome.

PATIENTS AND METHODS

We retrospectively analyzed the medical records of patients treated with rituximab in an internal medicine department of a tertiary hospital between 2007 and 2015, and identified all IE after this therapy. Events' severity was assessed using the Common Terminological Criteria of Adverse Events (version 4.3) definitions.

RESULTS

Among 101 patients treated with rituximab, we identified 228 IE in 74 (73.3%) of these patients (median follow-up 30.4months). Indication for rituximab was either autoimmune disease (AID) (52.5% of patients), or monoclonal hematological disease (MHD) (47.5%). Patients received an overall median number of 5 rituximab infusions [interquartile range: 4-8], representing a cumulative dose of 4340mg [2620-6160]. After last rituximab infusion, IE occurred after 3.1months [0.7-9.4]. Respectively, IE were severe in 28.1% of cases in patients treated for AID vs 58.0% in patients treated for MHD (p<0.001), due to opportunistic pathogens in 7.8% vs 11.0% (p=0.49) and fatal in 4.7% vs 13.0% (p=0.044). Factor associated with mortality were polymicrobial infection (p<0.001), monoclonal hematological disease (p=0.035), use of steroids over 10mg/d within the last two weeks (p=0.003), and rituximab cumulative dose (p<0.001). We identified a group of 10 patients (9.9%) showing life-threatening, polymicrobial, and opportunistic infections constituting a 'catastrophic infectious syndrome', which was lethal in 7 cases.

CONCLUSION

IE after treatment by rituximab can be extremely severe, especially in patients immunocompromised by several other drugs. Further studies should focus on the group with life-threatening polymicrobial infections.

Comparative efficacy of different chemotherapies for non-Hodgkin lymphoma: a network-meta analysis

This network meta-analysis (NMA) was conducted to integrate different chemotherapeutic regimens for non-Hodgkin lymphoma (NHL) patients. Overall survival (OS) and complete remission (CR) were considered as main outcome indicators to evaluate the efficacy of NHL chemotherapies. OS and CR data were extracted from included studies and represented by hazard ratio and odds ratio separately. Network structure and forest plots were further included to visually present the relative efficacy among different regimens. A total of 14 qualified publications with 4,167 patients were included. In OS results, no significant difference was observed from the 1-year OS. For 2-year, 3-year and 5-year OS, patients treated by CNOP exhibited the least favorable results. Moreover, significant advantages of R-CHOP treatment over CHOP and VMP were recognized in view of 3-year OS. In respect of CR, R-HDS presented significantly better outcomes than CNOP and VMP, and no significant difference was identified when compared to CHOP in forest plot. ProMACE-CytaBOM and R-HDS possessed the compelling cumulative ranking probability in OS or CR, indicating their competitive performance in NHL treatment while R-CHOP and I-CHOP yielded desirable in terms of long-term survival and short-term survival, respectively. To conclude, ProMACE-CytaBOM, I-CHOP, R-HDS and R-CHOP were recommended to go through further evaluation to confirm their superiority in NHL treatment. CNOP and VMP were discouraged after comprehensively analyzing OS and CR from NMA results.

Risk factors predisposing to the development of hypogammaglobulinemia and infections post-Rituximab

Rituximab (RTX) is a monoclonal antibody against CD20, commonly used in the treatment of hematological malignancies and autoimmune diseases. The use of RTX is related to the development of hypogammaglobulinemia and infections. Aim of this review is to summarize the evidence supporting the association of specific risk factors with the development of hypogammaglobulinemia and infections post-RTX. Immunological complications are more common in patients with malignant diseases as compared to non-malignant diseases. Moreover, the use of more than one dose of RTX, maintenance regimens, low pre-treatment basal immunoglobulin levels and the association with Mycophenolate and purine analogues represent risk factors for the development of hypogammaglobulinemia. The number of RTX courses, the evidence of low IgG levels for more than 6 months, the use of G-CSF, the occurrence of chronic lung disease, cardiac insufficiency, extra-articular involvement in patients with rheumatoid arthritis, low levels of IgG and older age have been correlated with a higher risk of infections. Even though the heterogeneity of the studies in terms of study population age and underlying disease, RTX schedules as well as differences in pre-treatment or concomitant therapy doesn't allow drawing definitive conclusions, the study of the literature highlight the association of specific risk factors with the occurrence of hypogammaglobulinemia and/or infections. A long term randomized controlled clinical trial could be useful to define a personalized evidence-based risk management plan for patients treated with RTX.

A randomized phase II study of standard-dose versus high-dose rituximab with BEAM in autologous stem cell transplantation for relapsed aggressive B-cell non-hodgkin lymphomas: long term results

High-dose rituximab (HD-R) combined with carmustine, cytarabine, etoposide and melphalan (BEAM) and autologous stem cell transplant (ASCT) was effective and tolerable in a single-arm prospective study of relapsed aggressive B-cell non-Hodgkin lymphoma (R-NHL). We performed a randomized phase 2 study comparing HD-R versus standard-dose rituximab (SD-R) in R-NHL. Ninety-three patients were randomized to HD-R (1000 mg/m² ) (n = 42) or SD-R (375 mg/m² ) (n = 51) administered on post-transplant days +1 and +8, using a Bayesian adaptive algorithm. The 2 treatment arms were balanced in regards to patient demographic and clinical characteristics. At a median follow-up of 7·92 years, the 5-year disease-free survival (DFS) and overall survival (OS) were 40% and 48%, respectively. We found no statistically significant differences between HD-R and SD-R in 5-year DFS (36% vs. 43%; P = 0·205) and OS (43% vs. 52%; P = 0·392). In multivariate analyses, only disease status before ASCT [residual disease versus complete remission (CR)] (hazard ratio [HR] 1·79, 95% confidence interval [CI]: 1·08-2·95) and number of prior treatments received (>2 vs. ≤2 lines of treatment) (HR 1·89, 95% CI: 1·13-3·18) were associated with worse DFS and OS. Patients who had SCT while in CR or who received ≤2 lines of treatment prior to SCT had better 5-year OS (57% vs. 35%; P = 0·02 and 54% vs. 30%, P = 0·001, respectively) in both arms. No differences in engraftments or adverse events were noted in the 2 arms. When combined with BEAM and ASCT in relapsed aggressive B-cell NHL, HD-R provided no DFS or OS advantage over SD-R. In patients who have been exposed to rituximab in the frontline or salvage setting, the addition of rituximab in the peri-transplant setting remains controversial.

Targeted Drugs as Maintenance Therapy after Autologous Stem Cell Transplantation in Patients with Mantle Cell Lymphoma

The treatment landscape for mantle cell lymphoma (MCL) is rapidly evolving toward the incorporation of novel and biologically targeted pharmaceuticals with improved disease activity and gentler toxicity profiles compared with conventional chemotherapeutics. Upfront intensive treatment of MCL includes autologous stem cell transplantation (SCT) consolidation aimed at deepening and lengthening disease remission, but subsequent relapse occurs. Maintenance therapy after autologous SCT in patients with MCL in remission features lower-intensity treatments given over extended periods to improve disease outcomes. Targeted drugs are a natural fit for this space, and are the focus of considerable clinical investigation. This review summarizes recent advances in the field and their potential impact on treatment practices for MCL.

Rituximab and protection from vaccine preventable diseases: applying the evidence to pediatric patients

INTRODUCTION

This article analyses and highlights the challenge of immunization and preventing vaccine preventable diseases in pediatric patients on rituximab. Rituximab is a chimeric anti-CD 20 monoclonal antibody that is an immunosuppressant affecting both cellular and humoral immunity. Children and adolescents on rituximab are at increased risk of infection and vaccine preventable diseases, and require additional strategies to optimize and maximize their protection against such illnesses. Areas covered: This article provides a comprehensive MEDLINE and Pubmed review of existing literature regarding vaccine immunogenicity and safety in patients on rituximab, and assists in providing an evidence base to develop immunization guidelines. Of particular note, the use of live-attenuated vaccines and optimum timing of vaccines post rituximab is considered and discussed. Expert commentary: The increasing use of rituximab in a variety of novel areas within pediatrics must be accompanied by informed discussion around mitigating the risks. These include immunosuppression, and potential susceptibility to infection. Optimizing vaccine status by establishing adequate antibody titers prior to commencement remains the best preventative strategy.

Role of Maintenance Therapy after High-Dose Chemotherapy and Autologous Hematopoietic Cell Transplantation in Aggressive Lymphomas: A Systematic Review

Significant uncertainty exists in regard to the efficacy of maintenance therapy after high-dose chemotherapy (HDC) as well as autologous stem cell transplantation (ASCT) for the treatment of patients with aggressive lymphoma. A systematic review was performed to evaluate the effectiveness of post-ASCT maintenance therapy in patients with relapsed/refractory lymphoma. A comprehensive literature search yielded 4476 studies and a total of 42 studies (11 randomized controlled trials [RCT], 9 retrospective comparative studies, and 22 single-arm studies) were included in the systematic review. There was significant heterogeneity in study design, chemotherapeutic regimens, post-ASCT maintenance strategies, patient enrollment criteria, and study endpoints. Our findings suggest that post-ASCT maintenance immune-targeting strategies, including PD-1/PD-L1 blocking antibodies, rituximab, and brentuximab, may improve progression-free survival but not overall survival. Collectively, the results indicate a need for testing new strategies with well-designed and adequately powered RCTs to better address the role of post-ASCT maintenance in relapsed/refractory lymphomas.

Rituximab as consolidation therapy did not improve outcome in patients with diffuse large B-cell lymphoma at complete response after dose-dense chemotherapy (CHOP-14)

The authors started a clinical trial to assess the efficacy and toxicity of rituximab (R) as consolidation in patients with diffuse large B-cell lymphoma, with poor prognostic factors, who were in complete response (CR) after dose-dense chemotherapy (CHOP-14). Four hundred sixty-five untreated patients, with advanced stages (III and IV), older (median age >60 years old), and high clinical risk, were treated with dose-dense CHOP-14 (cyclophosphamide 1500 mg/m(2), i.v., day 1; vincristine 2 mg, i.v., standard dose, day 1; epirubicin 120 mg/m(2), i.v., day 1; and prednisone 60 mg/m(2), p.o., days 1-5) every 14 days for six cycles. If CR was achieved, the patients were allocated to receive R (375 mg/m(2), days 1, 8, 15, and 22) at 3 and 9 months after chemotherapy. Three hundred twenty-five patients achieved CR (70%) and were allocated to receive R (151 patients) or not (174 patients). Actuarial curves at 5 years showed that progression-free survival (PFS) was 51% (95% confidence interval [CI]: 44%-58%) in the R group and 53% (95% CI: 47%-59%) in the observation group (p=0.8). Overall survival (OS) was 65% (95% CI: 58%-71%) and 66% (95% CI: 59%-72%), respectively (p=0.78). Late toxicities were more frequent in the R group. The authors showed that the use of R as a consolidation treatment was not useful to improve PFS and OS and toxicity secondary to R was frequent. They did not recommend the use of R as consolidation in this patient setting.

Maintenance rituximab after autologous stem cell transplantation in patients with mantle cell lymphoma

BACKGROUND

High-dose therapy and autologous stem cell transplantation (ASCT) improves outcomes for patients with mantle cell lymphoma (MCL), but relapse ultimately occurs in most patients. Recently presented interim results from a phase III prospective trial suggest maintenance rituximab (MR) after ASCT for MCL improves progression-free survival (PFS). The maturation of these data and any benefit of MR on overall survival (OS) remain to be defined.

PATIENTS AND METHODS

In this retrospective study, we examined a cohort of consecutive patients with MCL that underwent ASCT for MCL at our center and evaluated their outcomes according to whether they received MR after ASCT (n = 50) or did not (n = 107). MR was treated as a time-dependent covariate to account for variation in timing of its initiation.

RESULTS

MR was associated with an improved PFS [hazard ratio (HR) 0.44; confidence interval (CI) (0.24-0.80), P = 0.007] and overall survival (OS; HR 0.46; CI 0.23-0.93, P = 0.03) following a multivariate adjustment for confounding factors with a median follow-up of ∼5 years. Grade 4 neutropenia was increased (34% versus 18%, P = 0.04) in the MR group, but no effect on the rate of mortality unrelated to relapse was observed.

CONCLUSIONS

These data support that MR after ASCT for MCL confers a benefit in PFS and additionally suggest it may improve OS. General application of this strategy will require confirmation of benefit in prospective randomized trials.

The importance of radiotherapy on diffuse large B cell lymphoma treatment: a current review

Diffuse large B cell lymphoma is recognized as a heterogeneous group of hematological malignancies; two main subtypes germinal center B and activated B cells are well defined although 15% of patients remain with unclassifiable disease. R-CHOP treatment has proven to provide very effective results in limited or advanced stage of the disease. However, treatment solely involving R-CHOP submits the patient to possible chemotherapy-induced toxicities, which may be avoided with the use of radiotherapy. Patients with early stage localized disease or who are particularly unresponsive to chemotherapy may be more suitable for mixed modality treatment with R-CHOP and consolidative radiotherapy. Although radiotherapy is being slowly phased out by other treatment strategies including chemotherapy and therapeutic drugs, it is still a highly important method of treatment. The different forms of radiotherapy can be used alongside these "new-age" treatment strategies to further improve prognostic outcomes and overall survival rates. The establishment of radiotherapy as a treatment strategy provides a highly beneficial prognostic advantage in early stage, localized disease.

Rituximab after autologous stem cell transplantation enhances survival of B-cell lymphoma patients: a meta-analysis and systematic review

BACKGROUND

Numerous studies have demonstrated the efficacy of rituximab before autologous stem cell transplantation (ASCT) for the treatment of B-cell non-Hodgkin lymphoma, but the few studies on rituximab treatment after ASCT have not established conclusively the clinical benefits of this particular treatment regimen.

PATIENTS AND METHODS

We conducted a metaanalysis of 3 comparative studies encompassing 407 lymphoma patients treated with rituximab after ASCT.

RESULTS

Combined results revealed a significantly higher event-free survival (EFS) in the rituximab-treated (R+) group compared with the R- group (P = .003 at 1 year; P = .03 at 3 years; P = .001 at 4 years). Moreover, the R+ group also demonstrated higher overall survival (OS) and complete remission (CR) rates (P = .0006 and P < .0001, respectively, at 1 year) without a significant increase in adverse events.

CONCLUSIONS

According to the included articles, there were no differences in CR, overall response, 3-year EFS, or 3-year OS between rituximab-naïve patients and patients previously treated with rituximab before ASCT. Post-ASCT maintenance regimens including rituximab show increased EFS, OS, and CR.

Autologous stem cell transplantation with in vivo purged progenitor cells shows long-term efficacy in relapsed/refractory follicular lymphoma

High-dose chemotherapy with autologous stem cell transplantation (ASCT) has been shown effective in the control of relapsed/refractory follicular lymphoma. We evaluate the long-term outcome of patients with relapsed or refractory follicular lymphoma treated with ASCT with in vivo purged progenitors cells. We report the long-term results of a prospective multicenter phase 2 trial on 124 relapsed/refractory follicular lymphoma patients treated with a program of anthracycline-based debulking chemotherapy, immunochemotherapy, mobilization of in vivo purged PBSC followed by ASCT. Median age was 52 years; 14% of patients had grade 3A histology. Debulking chemotherapy produced CR in 16% and PR in 71%, while 13% of patients progressed. After rituximab, cyclophosphamide, vincristine, prednisone (R-COP), CR was obtained in 60% and PR in 35%; 118 patients successfully mobilized PBSC and 117 proceeded to ASCT. The harvest in all the 32 molecularly informative patients was bcl-2 negative. TRM was 0%. The 5-year PFS was 54% and the 5-year OS was 83%. After a median f-up of 6.7 years (range 1.5-13.6), 54% are still in CR. These data show that prolonged PFS is achievable in relapsed/refractory patients with high dose autologous transplantation of in vivo purged progenitor cells.

Immunreconstitution and infectious complications after rituximab treatment in children and adolescents: what do we know and what can we learn from adults?

Rituximab, an anti CD20 monoclonal antibody, is widely used in the treatment of B-cell malignancies in adults and increasingly in pediatric patients. By depleting B-cells, rituximab interferes with humoral immunity. This review provides a comprehensive overview of immune reconstitution and infectious complications after rituximab treatment in children and adolescents. Immune reconstitution starts usually after six months with recovery to normal between nine to twelve months. Extended rituximab treatment results in a prolonged recovery of B-cells without an increase of clinically relevant infections. The kinetic of B-cell recovery is influenced by the concomitant chemotherapy and the underlying disease. Intensive B-NHL treatment such as high-dose chemotherapy followed by rituximab bears a risk for prolonged hypogammaglobulinemia. Overall transient alteration of immune reconstitution and infections after rituximab treatment are acceptable for children and adolescent without significant differences compared to adults. However, age related disparities in the kinetic of immune reconstitution and the definitive role of rituximab in the treatment for children and adolescents with B-cell malignancies need to be evaluated in prospective controlled clinical trials.

[Vaccination in adult patients with chronic inflammatory rheumatic diseases]

Patients with chronic inflammatory rheumatic diseases often have an intrinsic and therapy associated increased susceptibility to infections which substantially contributes to morbidity and mortality of the patients. A large proportion of these infections are preventable by vaccination. For this reason in 2005 the standing vaccination committee (STIKO) recommended for patients with immunosuppression vaccination against pneumococcus, influenza, Haemophilus influenza b and meningococcus in addition to standard vaccinations, independent of age. Every patient should therefore be informed about a possible increase in susceptibility to infections and the recommended prevention by vaccination before implementation of immunosuppressive therapy.

Subcutaneous immunoglobulin in lymphoproliferative disorders and rituximab-related secondary hypogammaglobulinemia: a single-center experience in 61 patients

Intravenous immunoglobulin replacement therapy represents the standard treatment for hypogammaglobulinemia secondary to B-cell lymphoproliferative disorders. Subcutaneous immunoglobulin infusion is an effective, safe and well-tolerated treatment approach in primary immunodeficiencies but no extensive data are available on their use in secondary hypogammaglobulinemia, a frequent phenomenon occurring after treatment with anti-CD20 monoclonal antibodies in lymphoproliferative disorders. In this retrospective study we evaluated efficacy (serum IgG trough levels, incidence of infections per year, need for antibiotics) and safety (number of adverse events) of intravenous (300 mg/kg/4 weeks) versus subcutaneous (75 mg/kg/week) immunoglobulin replacement therapy in 61 patients. In addition, the impact of the infusion methods on quality of life was compared. All patients were treated with subcutaneous immunoglobulin, and 33 out of them had been previously treated with intravenous immunoglobulin. Both treatments appeared to be effective in replacing Ig production deficiency and in reducing the incidence of infectious events and the need for antibiotics. Subcutaneous immunoglobulin obtained a superior benefit when compared to intravenous immunoglobulin achieving higher IgG trough levels, lower incidence of overall infection and need for antibiotics. The incidence of serious bacterial infections was similar with both infusion ways. As expected, a lower number of adverse events was registered with subcutaneous immunoglobulin, compared to intravenous immunoglobulin, with no serious adverse events. Finally, we observed an improvement in health-related quality of life parameters after the switch to subcutaneous immunoglobulin. Our results suggest that subcutaneous immunoglobulin is safe and effective in patients with hypogammaglobulinemia associated to lymphoproliferative disorders.

A phase II study of a nonmyeloablative allogeneic stem cell transplant with peritransplant rituximab in patients with B cell lymphoid malignancies: favorably durable event-free survival in chemosensitive patients

The aim of this prospective phase II trial was to determine the safety and efficacy of a nonmyeloablative conditioning program incorporating peritransplant rituximab in patients with CD20+ B cell non-Hodgkin lymphoma (B-NHL) receiving an allogeneic stem cell transplant (allo-SCT). Fifty-one adult B-NHL patients, with a median age of 54 years, were treated with cyclophosphamide, fludarabine, and 200 cGy of total body irradiation. Rituximab 375 mg/m(2) was given on day -8 and in 4 weekly doses beginning day +21. Equine antithymocyte globulin was given to recipients of volunteer unrelated donor grafts. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and mycophenolate mofetil and tacrolimus, sirolimus, and methotrexate in 8 and 43 patients, respectively. Thirty-three patients received grafts from unrelated donors, and 18 received grafts from matched related donors. All patients engrafted. Full donor chimerism in bone marrow and peripheral T cells was seen in 92% and 89% of patients, respectively, at 3 months after allo-SCT. The cumulative incidence of grades II to IV acute GVHD at 6 months was 25% (95% confidence interval [CI], 13% to 38%) and grades III to IV was 11% (95% CI, 2% to 20%). The 2-year cumulative incidence of chronic GVHD was 29% (95% CI, 15% to 44%). The 2-year event-free and overall survival for all patients was 72% (95% CI, 59% to 85%) and 78% (95% CI, 66% to 90%), respectively. The 2-year event-free survival for chemosensitive patients was 84% (95% CI, 72% to 96%) compared with 30% (95% CI, 2% to 58%) for chemorefractory patients before allo-SCT (P < .001). This nonmyeloablative regimen, with peritransplant rituximab, is safe and effective in patients with B-NHL.

2013 IDSA clinical practice guideline for vaccination of the immunocompromised host

An international panel of experts prepared an evidenced-based guideline for vaccination of immunocompromised adults and children. These guidelines are intended for use by primary care and subspecialty providers who care for immunocompromised patients. Evidence was often limited. Areas that warrant future investigation are highlighted.

Multiple infusions of CD20-targeted T cells and low-dose IL-2 after SCT for high-risk non-Hodgkin's lymphoma: a pilot study

A pilot phase I clinical trial involving 15 infusions of anti-CD3 × anti-CD20 bispecific Ab (CD20Bi)-armed anti-CD3-activated T cells (aATC) and low-dose IL-2 was conducted in three non-Hodgkin's lymphoma (NHL) patients (two high-risk and one refractory) after autologous SCT. The feasibility of T-cell expansion, safety of aATC infusions, cytotoxic immune responses and trafficking of aATC were evaluated. Three NHL patients received 15 infusions of 5 × 10(9) aATC (three infusions/week for 3 weeks and one infusion/week for 6 weeks) between days 1 and 65 after SCT with IL-2. There were no dose-limiting toxicities. Chills, fever, hypotension and malaise were the common side effects. Engraftment was delayed in one patient with a low stem cell dose. CD20Bi aATC infusions induced specific cytotoxicity directed at lymphoma targets. Endogenous peripheral blood mononuclear cells from two patients mediated anti-lymphoma cytotoxicity above preSCT background (P<0.001). (111)In labeled aATC trafficked to the lungs at 1 h and accumulated in the liver and bone marrow after 24 h. aATC infusions given over 69 days in combination with IL-2 were safe, did not inhibit engraftment, and induced endogenous cytotoxic responses directed at lymphoma targets.

The effect of rituximab on vaccine responses in patients with immune thrombocytopenia

B-cell depletion may impair vaccine responses and increase infection risk in patients with immune thrombocytopenia (ITP). We investigated the effects of rituximab on antibody and cellular responses to Streptococcus pneumoniae polysaccharide and Haemophilus influenzae type b (Hib) vaccines in ITP patients. Of 60 patients in the main trial, 24 patients received both vaccines 6 months after rituximab (n = 17) or placebo (n = 7). Among 20 evaluable patients, 3 of 14 (21%) in the rituximab group and 4 of 6 (67%) in the placebo group achieved a fourfold increase in anti-pneumococcal antibodies (P = .12). For anti-Hib antibodies, 4 of 14 (29%) and 5 of 6 (83%), respectively, achieved a fourfold increase (P < .05). Fewer patients in the rituximab group demonstrated Hib killing (2 of 14 [14%], 5 of 6 [83%], P < .05). Three of 14 rituximab-treated patients failed to respond to vaccines by any criteria. After vaccinations, preplasma cell blasts and interferon-γ-secreting T cells were reduced in rituximab-treated patients. Antibody responses were impaired for at least 6 months after rituximab. Cellular immunity was reduced in parallel with depleted B-cell pools. These findings have implications for the timing of vaccinations and the mechanism of infection after rituximab in ITP patients.

Monoclonal antibodies in conditioning regimens for hematopoietic cell transplantation

Monoclonal antibodies are increasingly being incorporated in conditioning regimens for autologous or allogeneic hematopoietic cell transplantation (HCT). The benefit of adding rituximab to autologous HCT regimens is purportedly related to in vivo purging of clonal B cells. Randomized trials comparing the addition (or not) of rituximab to high-dose therapy regimens are lacking. No benefit of standard-dose radioimmunotherapy-based regimens for autografting in aggressive lymphomas was seen in a randomized controlled study. The incorporation of rituximab into allogeneic HCT regimens aims to improve responses while reducing nonrelapse mortality resulting from acute graft-versus-host disease. The optimal dose and administration schedule of rituximab in this setting are unknown, and potentially serious complications from increased infections owing to prolonged (and profound) cytopenias or persistent hypogammaglobulinemia are of concern. Radioimmunotherapy-based conditioning for allografting holds promise as a modality to optimize tumor control and synergize adoptive immunotherapy effects, but it remains experimental at this time. The addition of alemtuzumab to allogeneic HCT regimens is associated with prolonged lymphopenia and impaired immune reconstitution, high relapse rates, and serious infections. The optimal dose and schedule of alemtuzumab to avoid prolonged immune paresis remain elusive. It is anticipated that additional monoclonal antibodies will soon become available that can be incorporated into HCT regimens after safety and clinical efficacy are demonstrated.

A new approach for eradication of residual lymphoma cells by host nonreactive anti-third-party central memory CD8 T cells

Generation of T cells endowed with graft-versus-leukemia (GVL) and depleted of graft-versus-host (GVH) activity represents a highly desirable goal in bone marrow transplantation (BMT). Here, we demonstrate that donor anti-third-party CD8 T cells with central memory phenotype (Tcm) exhibit marked GVL reactivity through a unique T-cell receptor-independent mechanism. Thus, in a residual disease mouse model, Tcm therapy following autologous BMT led to significant survival prolongation, with 30% to 40% of the treated mice displaying long-term tumor-free survival. A more impressive finding was that infusion of donor Tcm in an allogeneic model rapidly eliminated residual lymphoma cells and led to long-term survival of 100% in the absence of GVH disease. Collectively, the strong GVL reactivity of anti-third-party Tcm, coupled with their demonstrated enhancement of bone marrow allografting, suggests that the use of Tcm therapy in conjunction with allogeneic T-cell-depleted BMT could be of particular benefit in patients with B-cell malignancies who cannot tolerate intensive myeloablative conditioning.

CD20-targeted T cells after stem cell transplantation for high risk and refractory non-Hodgkin's lymphoma

A phase I trial of infusing anti-CD3 × anti-CD20 bispecific antibody (CD20Bi) armed activated T cells (aATC) was conducted in high-risk/refractory non-Hodgkin's lymphoma patients to determine whether aATC infusions are safe, affect immune recovery, and induce an antilymphoma effect. Ex vivo expanded ATC from 12 patients were armed with anti-CD20 bispecific antibody, cryopreserved, and infused after autologous stem cell transplantation (SCT). Patients underwent SCT after high-dose chemotherapy, and aATC infusions were started on day +4. The patients received 1 infusion of aATC per week for 4 weeks after SCT with doses of 5, 10, 15, and 20 × 10(9). aATC infusions were safe and did not impair engraftment. The major side effects were chills, fever, hypotension, and fatigue. The mean number of IFN-γ Enzyme-linked Immunosorbent Spots (ElSpots) directed at CD20 positive lymphoma cells (DAUDI, P = .0098) and natural killer cell targets (K562, P < .0051) and the mean specific cytotoxicity directed at DAUDI (P = .037) and K562 (P = .002) from pre-SCT to post-SCT were significantly higher. The increase in IFN-γ EliSpots from pre-SCT to post-SCT in patients who received armed ATC after SCT were significantly higher than those in patients who received SCT alone (P = .02). Serum IL-7, IL-15, Macrophage inflammatory protein (MIP)-1 beta, IP-10, MIP-1α, and Monokine induced by gamma interferone increased within hours after infusion. Polyclonal and specific antibodies were near normal 3 months after SCT. aATC infusions were safe and increased innate and specific antilymphoma cell immunity without impairing antibody recovery after SCT.

Incidence of hypogammaglobulinemia in patients receiving rituximab and the use of intravenous immunoglobulin for recurrent infections

Rituximab targets normal B cells and tumor B cells. We used a unique data-mining tool to identify patients with lymphoma who were treated with rituximab and who had serial pre and post rituximab immunoglobulin concentrations evaluated. After treatment, 39% (69/179) of patients had low levels of immunoglobulin G. Recurrent sinopulmonary infections were seen in 6.6% (14/211). Intravenous immune globulin appeared to reduce the frequency of infection.

BACKGROUND

Rituximab has altered the treatment approach to B-cell malignancies and other diseases. Reports consider that rituximab had limited impact on serum immunoglobulins. However, anecdotes suggest that rituximab can cause symptomatic hypogammaglobulinemia. This retrospective study examined the relationship among rituximab, hypogammaglobulinemia, and treatment of symptomatic hypogammaglobulinemia with intravenous immune globulin (IVIG).

METHODS

Patients with serial quantitative serum immunoglobulin (SIgG) concentrations before and subsequent to rituximab administration at Memorial Sloan-Kettering Cancer Center were identified. Information regarding rituximab administration, SIgG concentrations, frequency of infection, and administration of IVIG were recorded.

RESULTS

Between December 1998 and April 2009, 211 patients with B-cell lymphoma treated with rituximab and with serial SIgG concentrations were identified. One hundred seventy-nine (85%) patients had normal SIgG before rituximab, 32 (15%) had low SIgG. After rituximab use, hypogammaglobulinemia was identified in 38.54% of patients with initially normal SIgG. The risk was greater in patients who received maintenance rituximab. Symptomatic hypogammaglobulinemia that prompted IVIG administration developed in 6.6% of patients.

CONCLUSIONS

In this data set, rituximab administration was associated with a high frequency of hypogammaglobulinemia, particularly symptomatic hypogammaglobulinemia, among patients who received multiple courses of rituximab. Baseline and periodic monitoring of SIgGs is appropriate in patients who receive rituximab.

Is there any role for transplantation in the rituximab era for diffuse large B-cell lymphoma?

Salvage chemotherapy followed by high-dose therapy and autologous stem cell transplantation is the standard of treatment for chemosensitive relapses in diffuse large B-cell lymphoma. The addition of rituximab to chemotherapy has improved the response rate and failure-free survival after first-line treatment and relapses. Fewer relapses are expected, although there is no consensus on the best salvage regimen. The intergroup Collaborative Trial in Relapsed Aggressive Lymphoma (CORAL) set the limits for this standard of treatment after first comparing 2 salvage regimens: rituximab, ifosfamide, etoposide, and carboplatin (R-ICE) and rituximab, dexamethasone, aracytine, and cisplatin (R-DHAP). There was no difference in response rates or survivals between these salvage regimens. Several factors affected survival: prior treatment with rituximab, early relapse (< 12 months), and a secondary International Prognostic Index score of 2-3. For patients with 2 factors, the response rate to salvage was only 46%, which identified easily a group with poor outcome. Moreover, patients with an ABC subtype or c-MYC translocation responded poorly to treatment. More than 70% of patients will not benefit from standard salvage therapy, and continued progress is needed. Studies evaluating immunotherapy after transplantation, including allotransplantation, new conditioning regimens with radioimmunotherapy and other combinations of chemotherapy based on diffuse large B-cell lymphoma subtype, are discussed herein. Early relapses and/or patients refractory to upfront rituximab-based chemotherapy have a poor response rate and prognosis. A better biological understanding of these patients and new approaches are warranted.

Rituximab maintenance therapy after autologous stem-cell transplantation in patients with relapsed CD20(+) diffuse large B-cell lymphoma: final analysis of the collaborative trial in relapsed aggressive lymphoma

PURPOSE

The standard treatment for relapsed diffuse large B-cell lymphoma (DLBCL) is salvage chemotherapy followed by high-dose therapy and autologous stem-cell transplantation (ASCT). The impact of maintenance rituximab after ASCT is not known.

PATIENTS AND METHODS

In total, 477 patients with CD20(+) DLBCL who were in their first relapse or refractory to initial therapy were randomly assigned to one of two salvage regimens. After three cycles of salvage chemotherapy, the responding patients received high-dose chemotherapy followed by ASCT. Then, 242 patients were randomly assigned to either rituximab every 2 months for 1 year or observation.

RESULTS

After ASCT, 122 patients received rituximab, and 120 patients were observed only. The median follow-up time was 44 months. The 4-year event-free survival (EFS) rates after ASCT were 52% and 53% for the rituximab and observation groups, respectively (P = .7). Treatment with rituximab was associated with a 15% attributable risk of serious adverse events after day 100, with more deaths (six deaths v three deaths in the observation arm). Several factors affected EFS after ASCT (P < .05), including relapsed disease within 12 months (EFS: 46% v 56% for relapsed disease after 12 months), secondary age-adjusted International Prognostic Index (saaIPI) more than 1 (EFS: 37% v 61% for saaIPI < 1), and prior treatment with rituximab (EFS: 47% v 59% for no prior rituximab). A significant difference in EFS between women (63%) and men (46%) was also observed in the rituximab group. In the Cox model for maintenance, the saaIPI was a significant prognostic factor (P < .001), as was male sex (P = .01).

CONCLUSION

In relapsed DLBCL, we observed no difference between the control group and the rituximab maintenance group and do not recommend rituximab after ASCT.

Rituximab-treated patients have a poor response to influenza vaccination

The efficacy of influenza vaccination in patients treated with rituximab is a clinically important question. Rheumatology clinics are populated with patients receiving rituximab for a broad array of disorders. Although several studies have explored the efficacy of other vaccines in rituximab-treated populations, results have been conflicting. We wished to define influenza vaccine efficacy in a rituximab-treated cohort. We examined 17 evaluable subjects treated with rituximab for rheumatologic conditions. T cell subsets, B cells subsets, T cell function, and B cell function were evaluated at specific time points along with hemagglutinination inhibition titers after receiving the standard inactivated influenza vaccine. T cell subset counts were significantly different than controls but did not change with rituximab. B cells depleted in all patients but were in various stages of recovery at the time of vaccination. Influenza vaccine responsiveness was poor overall, with only 16 % of subjects having a four-fold increase in titer. Pre-existing titers were retained throughout the study, however. The ability to respond to the influenza vaccine appeared to be related to the degree of B cell recovery at the time of vaccination. This study emphasizes that antibody responses to vaccine are impaired in subjects treated with rituximab and supports the concept that B cell recovery influences influenza vaccine responsiveness.

Phase II trial of 131-Iodine tositumomab with high-dose chemotherapy and autologous stem cell transplantation for relapsed diffuse large B cell lymphoma

The purpose of this study was to evaluate the standard outpatient dose of 131-Iodine tositumomab (75 cGy) combined with high-dose carmustine, etoposide, cytarabine, and melphalan (BEAM) followed by autologous stem cell rescue for the treatment of chemotherapy-sensitive relapsed or refractory, or high-risk first complete remission (CR) patients with diffuse large B cell non-Hodgkin's lymphoma (DLBCL). Forty patients with chemotherapy-sensitive persistent or relapsed or high/intermediate or high international prognostic index DLCBL were treated in a phase II trial combining 75 cGy 131-Iodine tositumomab with high-dose BEAM followed by autologous stem cell transplantation. The CR rate after transplantation was 78%, and the overall response rate was 80%. Short-term and long-term toxicities were similar to historical control patients treated with BEAM alone. With a median follow-up of 6 years (range, 3-10 years), the 5-year overall survival (OS) was 72% (95% confidence interval [CI], 55%-83%), and the 5-year progression-free survival (PFS) rate was 70% (95% CI, 53%-82%). The PFS and OS were encouraging in this group of chemotherapy-sensitive persistent, relapsed, or high-risk patients with DLBCL. A follow-up phase III trial with 131-Iodine tositumomab/BEAM vs rituximab/BEAM was planned based on this information.

Hematopoietic cell transplantation for B-cell lymphoma: an update

BACKGROUND

B-cell lymphoma comprises the majority of non-Hodgkin lymphomas worldwide. Hematopoietic cell transplantation (HCT) is used for patients with high-risk, relapsed, or refractory B-cell lymphoma.

METHODS

The current medical literature and the results of recently published trials were reviewed to provide an update on the most common indications for HCT in B-cell lymphoma.

RESULTS

Autologous HCT has evolving and new roles in the treatment of patients with high-risk diffuse large B-cell cell lymphoma, mantle cell lymphoma, and HIV-related lymphoma. Reduced-intensity conditioning has largely replaced older myeloablative conditioning regimens, making allogeneic transplantation safer for more patients with lymphoma.

CONCLUSIONS

The indication and timing of HCT depend on the patient's histology, age, and response to previous therapies. HCT is an essential component in the armamentarium to treat B-cell lymphoma.

Prophylactic rituximab after allogeneic transplantation decreases B-cell alloimmunity with low chronic GVHD incidence

B cells are involved in the pathogenesis of chronic GVHD (cGVHD). We hypothesized that prophylactic anti-B-cell therapy delivered 2 months after transplantation would decrease allogeneic donor B-cell immunity and possibly the incidence of cGVHD. Therefore, in the present study, patients with high-risk chronic lymphocytic leukemia (n = 22) and mantle-cell lymphoma (n = 13) received a total lymphoid irradiation of 80 cGy for 10 days and antithymocyte globulin 1.5 mg/kg/d for 5 days. Rituximab (375 mg/m(2)) was infused weekly on days 56, 63, 70, and 77 after transplantation. The incidence of acute GVHD was 6%. The cumulative incidence of cGVHD was 20%. Nonrelapse mortality was 3%. Rituximab treatment after allogeneic transplantation significantly reduced B-cell allogeneic immunity, with complete prevention of alloreactive H-Y Ab development in male patients with female donors (P = .01). Overall survival and freedom from progression at 4 years for chronic lymphocytic leukemia patients were 73% and 47%, respectively; for mantle-cell lymphoma patients, they were 69% and 53%, respectively.