Late-onset neutropenia after treatment with rituximab for rheumatoid arthritis and other autoimmune diseases: data from the AutoImmunity and Rituximab registry

Utilizing temporal pattern of adverse event reports to identify potential late-onset adverse events

OBJECTIVES

Through the use of FDA adverse event reporting system (FAERS) dataset, this study analyzes the pattern of time-to-event (TTE) for drugs and adverse events, and suggest ways to identify candidate late-onset events for monitoring.

METHODS

The duration between administration date of the drug and the onset of adverse events was explored with using FAERS data from 2012-2021. The fold change of proportional reporting ratios or reporting odds ratios were calculated to identify enriched events in the later period and to suggest the late-onset events for further monitoring. To compare the findings, we used the claims database of the Korean National Health Insurance Service (NHIS).

RESULTS

A total of 1,426,781 reports were included. The median TTE was 10 days (interquartile range [IQR]: 0-98 days), with 11.5% (n = 164,093) reporting events that occurred at least one year after administration. TTE and fold change analysis captured historical cases of late-onset events, while generating an additional less-explored list of events. The results for tumor necrosis factor (TNF) inhibitors were compared using the NHIS dataset.

CONCLUSION

Our study provides a comprehensive analysis of the FAERS dataset, focusing on TTE data. Periodic summarization of reports would be helpful in monitoring the late-onset events.

A Systematic Review and Meta-analysis of Rituximab-Associated Infections Among Children and Adolescents With Glomerular Disease: Focus on the Risk of Infections

OBJECTIVE

This systematic review and meta-analysis aimed to explore rituximab (RTX) associated infectious complications in children with glomerular disease.

METHODS

We performed an electronic search of PubMed, International Scientific Information (ISI), Scopus, and EMBASE between January 2010 and July 2021. Infection rates and total drug-related adverse events were the outcomes. Statistical heterogeneity was evaluated by using the I2 statistic. When there was statistical evidence of heterogeneity (I2 > 50%, p > 0.1), a random-effect model was adopted. Data analysis was performed with Stata17.0 software.

RESULTS

A total of 7 studies with 668 patients (136 with lupus nephritis [LN] and 532 with nephrotic syndrome were included in the meta-analysis. The pooled risk ratio showed that the administration of RTX was significantly associated with lower risk of infectious complications in patients with LN and nephrotic syndrome (0.72 [95% CI 0.58, 0.85]) when compared with population data of patients without glomerular disease (p = 0.2). There was no significant difference between the LN and nephrotic syndrome groups in terms of total serious adverse events or the occurrence of infections. There was significant heterogeneity among the reported studies (Q = 42.39, p < 0.001, I2 = 81%).

CONCLUSION

Administration of RTX in children with glomerular disease is associated with a lower rate of infections when compared with population data of patients without LN or nephrotic syndrome. Additional high-quality randomized controlled trials with long-term follow-up are needed to identify the long-term potential complications. Trial registration PROPERO ID: CRD42021274869 (https://www.crd.york.ac/prospero/display_record.php?).

Hypogammaglobulinemia, late-onset neutropenia, and infections following rituximab

Rituximab is a chimeric anti-CD20 monoclonal antibody that targets CD20-expressing B lymphocytes, has a well-defined efficacy and safety profile, and is broadly used to treat a wide array of diseases. In this review, we cover the mechanism of action of rituximab and focus on hypogammaglobulinemia and late-onset neutropenia-2 immune effects secondary to rituximab-and subsequent infection. We review risk factors and highlight key considerations for immunologic monitoring and clinical management of rituximab-induced secondary immune deficiencies. In patients treated with rituximab, monitoring for hypogammaglobulinemia and infections may help to identify the subset of patients at high risk for developing poor B cell reconstitution, subsequent infections, and adverse complications. These patients may benefit from early interventions such as vaccination, antibacterial prophylaxis, and immunoglobulin replacement therapy. Systematic evaluation of immunoglobulin levels and peripheral B cell counts by flow cytometry, both at baseline and periodically after therapy, is recommended for monitoring. In addition, in those patients with prolonged hypogammaglobulinemia and increased infections after rituximab use, immunologic evaluation for inborn errors of immunity may be warranted to further risk stratification, increase monitoring, and assist in therapeutic decision-making. As the immunologic effects of rituximab are further elucidated, personalized approaches to minimize the risk of adverse reactions while maximizing benefit will allow for improved care of patients with decreased morbidity and mortality.

Anti-CD20 therapies in multiple sclerosis: From pathology to the clinic

The immune system plays a significant role in multiple sclerosis. While MS was historically thought to be T cell-mediated, multiple pieces of evidence now support the view that B cells are essential players in multiple sclerosis pathogenic processes. High-efficacy disease-modifying therapies that target the immune system have emerged over the past two decades. Anti-CD20 monoclonal antibodies selectively deplete CD20+ B and CD20+ T cells and efficiently suppress inflammatory disease activity. These monotherapies prevent relapses, reduce new or active magnetic resonance imaging brain lesions, and lessen disability progression in patients with relapsing multiple sclerosis. Rituximab, ocrelizumab, and ofatumumab are currently used in clinical practice, while phase III clinical trials for ublituximab have been recently completed. In this review, we compare the four anti-CD20 antibodies in terms of their mechanisms of action, routes of administration, immunological targets, and pharmacokinetic properties. A deeper understanding of the individual properties of these molecules in relation to their efficacy and safety profiles is critical for their use in clinical practice.

Rituximab dose-dependent infection risk in rheumatoid arthritis is not mediated through circulating immunoglobulins, neutrophils or B cells

OBJECTIVES

Rituximab (RTX) is a safe and effective treatment for RA. A dose-dependent infection risk was found in the REDO trial. Some studies associate RTX use with higher infection risks, possibly explained by low immunoglobulin levels and/or neutropenia. Additionally, a higher infection risk shortly after RTX infusion is reported. The objectives of this study were (i) to compare incidence rates of infections between doses and over time, and (ii) to assess B-cell counts, immunoglobulin levels, neutrophil counts and corticosteroid/disease modifying rheumatic drug use as mediating factors between RTX study dose and infection risk.

METHODS

Post hoc analyses of the REDO trial were performed. Infection incidence rates between RTX dosing groups and between time periods were compared using Poisson regression. A step-wise mediation analysis was performed to investigate if any of the factors mentioned above act as a mediator in the observed dose-dependent difference in infection risk.

RESULTS

The potential mediators that were investigated (circulating B-cell counts, immunoglobulin levels, neutrophil counts and drug use) did not explain the dose-dependent infection risk observed in the REDO trial. Additionally, a trend towards a time-dependent infection risk was found, with higher infection rates shortly after RTX infusion.

CONCLUSIONS

These secondary analyses of the REDO trial confirmed the observed dose-dependent infection risk. Additionally, we found that infection risks were higher shortly after RTX infusion. However, a mediating pathway was not found.

Real world safety of CT-P10 (anti-CD 20 monoclonal antibodies biosimilar) in rheumatic and autoimmune diseases

BACKGROUND

Rituximab (RTX), anti-CD 20 monoclonal antibodies, has been approved for many rheumatic and autoimmune diseases, the use of RTX is still limited due to financial constrain. Biosimilar RTX may increase access by offering patients a more affordable option, lead to improved patient outcomes. However, real-world data related to its immediate and short-term safety is scarce. This study aimed to evaluate the real-world immediate and short-term safety profiles of CT-P10, a biosimilar of Rituximab, in patients with rheumatic and autoimmune diseases.

METHODS

This prospective study included patients diagnosed with rheumatic or autoimmune diseases, aged ≥ 18 years, who were treated with biosimilar RTX at Siriraj or Ramathibodi Hospital during February 2019 to May 2019. Patients were followed up through 6 months after the infusions.

RESULTS

Of the 74 patients, with 124 infusions, 84% were females with mean age (SD) of 49.4 (15.7) years. The most common rheumatic and autoimmune disease included in this study was systemic lupus erythematosus (26%). All immediate adverse events (AEs) (15 out of 124 infusions) were mild requiring only symptomatic and supportive treatment. Short-term AEs included infection (N = 35), hematologic abnormalities (N = 33), chylous ascites (N = 1), and others (N = 10). Two deaths were related to serious bacterial and viral infection. Hematologic AEs comprised anemia (N = 5), neutropenia (N = 10), lymphopenia (N = 15), and thrombocytopenia (N = 3).

CONCLUSION

In this real-world study, biosimilar RTX (CT-P10) has favorable immediate and short-term safety profiles. However, further studies with large sample size and long-term follow-up in real-world practice are still required to confirm the result.

Advancing Biologic Therapy for Refractory Autoimmune Hepatitis

Biologic agents may satisfy an unmet clinical need for treatment of refractory autoimmune hepatitis. The goals of this review are to present the types and results of biologic therapy for refractory autoimmune hepatitis, indicate opportunities to improve and expand biologic treatment, and encourage comparative clinical trials. English abstracts were identified in PubMed by multiple search terms. Full-length articles were selected for review, and secondary and tertiary bibliographies were developed. Rituximab (monoclonal antibodies against CD20 on B cells), infliximab (monoclonal antibodies against tumor necrosis factor-alpha), low-dose recombinant interleukin 2 (regulatory T cell promoter), and belimumab (monoclonal antibodies against B cell activating factor) have induced laboratory improvement in small cohorts with refractory autoimmune hepatitis. Ianalumab (monoclonal antibodies against the receptor for B cell activating factor) is in clinical trial. These agents target critical pathogenic pathways, but they may also have serious side effects. Blockade of the B cell activating factor or its receptors may disrupt pivotal B and T cell responses, and recombinant interleukin 2 complexed with certain interleukin 2 antibodies may selectively expand the regulatory T cell population. A proliferation-inducing ligand that enhances T cell proliferation and survival is an unevaluated, potentially pivotal, therapeutic target. Fully human antibodies, expanded target options, improved targeting precision, more effective delivery systems, and biosimilar agents promise to improve efficacy, safety, and accessibility. In conclusion, biologic agents target key pathogenic pathways in autoimmune hepatitis, and early experiences in refractory disease encourage clarification of the preferred target, rigorous clinical trial, and comparative evaluations.

An update on the incidence, risk factors and mechanisms of rituximab-associated neutropenia

With the increasing application of rituximab (RTB) in hematological diseases and autoimmune diseases (AIDs), we have gradually increased our awareness of the adverse reaction of rituximab-associated neutropenia (RAN), but little is known about its true incidence rate, susceptibility risk factors and exact pathogenesis. At present, research groups have conducted a large number of studies on different populations. The team found that age (> 60), advanced disease, systemic lupus erythematosus (SLE) and combined cyclophosphamide therapy were independent risk factors for RAN. However, its exact mechanism is not completely clear. Several hypotheses have been put forward to solve this question, including the production of anti-neutrophil antibodies after RTB, the generation disorder and neutrophil maturation stagnation caused by abnormal B-cell reconstruction, and the amplification of T-large granular lymphocyte population that may induce neutrophil apoptosis. However, there are still many unsolved problems in all aspects of RAN. This article is an update of the incidence rate, risk factors and mechanisms of RAN.

Derisking CD20-therapies for long-term use

Anti-CD20 have quickly become the mainstay in the treatment of multiple sclerosis (MS) and other neuroinflammatory conditions. However, when they are used as a maintenance therapy the balance between risks and benefits changes. In this review, we suggested six steps to derisk anti-CD20. Firstly and secondly, adequate infectious screening followed by vaccinations before starting anti-CD20 are paramount. Third, family planning needs to be discussed upfront with every woman of childbearing age. Fourth, infusion reactions should be adequately managed to avoid treatment interruption. After repeated infusions, it becomes important to detect and prevent anti-CD20-related adverse events. Fifth, we recommended measuring immunoglobulin levels and reviewing vaccinations annually as well as counselling adequate fever management. For female patients, we emphasised the importance to engage with the local breast cancer screening programs. Sixth, to fundamentally derisk anti-CD20 therapies, we need evidence-based approaches to reduce dosing intervals and guide retreatment.

Late-onset neutropenia after anti-CD20 therapy for multiple sclerosis, neuromyelitis optica spectrum disorders and MOG antibody-associated disease: A prospective study

Late-onset neutropenia (LON) after anti-CD20 therapy is a poorly described side effect in inflammatory disorders of the CNS. In this prospective study, patients treated with Rituximab or Ocrelizumab for MS, neuromyelitis optica spectrum disorders or MOG antibody-associated disease (MOGAD) were asked to perform complete blood count (CBC) every two weeks for six months, with the aim of identifying LON. Out of 152 patients, two (1,32%) had an absolute neutrophil count <1,000/mm³: one patient with MOGAD had agranulocytosis and one patient with MS had grade 3 neutropenia. Both were asymptomatic. These results confirm that LON after anti-CD20 therapy in inflammatory disorders of the CNS is not exceptional. Nevertheless, this biological complication remains too infrequent to justify close systematic CBC follow-up.

Drug-Induced Idiosyncratic Agranulocytosis - Infrequent but Dangerous

Drug-induced agranulocytosis is a life-threatening side effect that usually manifests as a severe form of neutropenia associated with fever or signs of sepsis. It can occur as a problem in the context of therapy with a wide variety of drug classes. Numerous drugs are capable of triggering the rare idiosyncratic form of agranulocytosis, which, unlike agranulocytosis induced by cytotoxic drugs in cancer chemotherapy, is characterised by “bizzare” type B or hypersensitivity reactions, poor predictability and a mainly low incidence. The idiosyncratic reactions are thought to be initiated by chemically reactive drugs or reactive metabolites that react with proteins and may subsequently elicit an immune response, particularly directed against neutrophils and their precursors. Cells or organs that exhibit specific metabolic and biotransformation activity are therefore frequently affected. In this review, we provide an update on the understanding of drug-induced idiosyncratic agranulocytosis. Using important triggering drugs as examples, we will summarise and discuss the chemical, the biotransformation-related, the mechanistic and the therapeutic basis of this clinically relevant and undesirable side effect.

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.

Incidence, Clinical Features, and Outcomes of Late-Onset Neutropenia From Rituximab for Autoimmune Disease

OBJECTIVE

Late-onset neutropenia (LON) is an underrecognized complication of rituximab treatment. We undertook this study to describe its incidence, risk factors, clinical features, management, and recurrence.

METHODS

We conducted a single-center retrospective cohort study of 738 adult patients with autoimmune disease who were treated with rituximab to induce continuous B cell depletion. The primary outcome measure was LON, defined as an unexplained absolute neutrophil count of <1,000 cells/µl during B cell depletion. Secondary outcome measures included incidental diagnosis, fever, sepsis, filgrastim use, and recurrent LON. We assessed predictors of LON using Cox proportional hazards regression models. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

We identified 107 episodes of LON in 71 patients. The cumulative incidence at 1 year of B cell depletion therapy was 6.6% (95% CI 5.0-8.7). The incidence rate during the first year was higher compared to thereafter (7.2 cases per 100 person-years [95% CI 5.4-9.6] versus 1.5 cases per 100 person-years [95% CI 1.0-2.3]). Systemic lupus erythematosus and combination therapy with cyclophosphamide were each independently associated with an increased risk of LON (adjusted HR 2.96 [95% CI 1.10-8.01] and 1.98 [95% CI 1.06-3.71], respectively). LON was not observed in minimal change disease or focal segmental glomerulosclerosis. The majority of episodes (59.4%) were asymptomatic. Fever and sepsis complicated 31.3% and 8.5% of episodes, respectively. Most patients (69%) were treated with filgrastim. Rituximab rechallenge occurred in 87% of patients, of whom 21% developed recurrent LON.

CONCLUSION

LON is common and often incidental. Most cases are reversible and respond well to filgrastim. However, LON can be associated with serious infections and thus warrants vigilant monitoring.

Hematological Manifestations among Patients with Rheumatic Diseases

BACKGROUND

Rheumatic diseases have many hematological manifestations. Blood dyscrasias and other hematological abnormalities are sometimes the first sign of rheumatic disease. In addition, novel antirheumatic biological agents may cause cytopenias.

SUMMARY

The aim of this review was to discuss cytopenias caused by systemic lupus erythematosus and antirheumatic drugs, Felty's syndrome in rheumatoid arthritis, and autoimmune hemolytic anemia, thrombosis, and thrombotic microangiopathies related to rheumatological conditions such as catastrophic antiphospholipid syndrome and scleroderma renal crisis. Key Message: The differential diagnosis of various hematological disorders should include rheumatic autoimmune diseases among other causes of blood cell and hemostasis abnormalities. It is crucial that hematologists be aware of these presentations so that they are diagnosed and treated in a timely manner.

Rituximab in people living with HIV affected by immune-mediated renal diseases: a case-series

Over the last two decades, rituximab (RTX) has played an important role in the treatment of some lymphoproliferative malignancies and immune-mediated diseases. RTX administration is generally safe and well-tolerated, but side effects including late-onset neutropenia, hypogammaglobulinemia, hepatitis B reactivation and rare cases of progressive multifocal leukoencephalopathy have been observed after its administration. Although there are no absolute contraindications regarding its use in people living with HIV (PLWH), the prescription of this drug has been principally limited in patients with oncohematological diseases. In this report, we described the outcome of four PLWH who underwent RTX therapy after the diagnosis of immune-mediated renal disease. The main RTX-associated adverse effects were leukopenia, late-onset neutropenia and decline of CD4+ and CD8+ T-cell counts. In addition, two of the four patients experienced pneumonia requiring hospitalization within six months from the last RTX infusion. We suggest that RTX should be used with caution in PLWH until further evidence emerges on its safety profile in this vulnerable population.

Prevention Strategies to Minimize the Infection Risk Associated with Biologic and Targeted Immunomodulators

The introduction of biologic and targeted immunomodulators is a significant breakthrough in the therapeutic area of various fields of medicine. The occurrence of serious infections, a complication of secondary immunosuppression associated with these agents, leads to increased morbidity and mortality. Implementing preventive strategies could minimize infection-related complications and improve therapeutic outcomes. The purpose of this review is to focus on current evident approaches regarding screening, monitoring, preventing (immunization and chemoprophylaxis), and management of infections in patients who are candidates for about 70 biologic and targeted immunomodulators. Recommendations are based on relevant guidelines, especially the ESCMID Study Group for Infections in Compromised Hosts (ESGICH) Consensus Document series published in 2018.

Predicting Severe Infection and Effects of Hypogammaglobulinemia During Therapy With Rituximab in Rheumatic and Musculoskeletal Diseases

OBJECTIVE

To evaluate predictors of serious infection events (SIEs) during rituximab (RTX) therapy and effects of hypogammaglobulinemia on SIE rates, and humoral response and its persistence after discontinuation of RTX in the treatment of rheumatic and musculoskeletal diseases (RMDs).

METHODS

A retrospective longitudinal study of 700 RMD patients treated with RTX in a single center was conducted. Immunoglobulin levels were measured at baseline and at 4-6 months after each treatment cycle. Baseline predictors of SIEs were assessed using multivariable logistic regression; for RTX cycles 2-4, a mixed-effects logistic regression model was used.

RESULTS

A total of 507 patients (72%) had rheumatoid arthritis, 94 (13%) had systemic lupus erythematosus, 49 (7%) had antineutrophil cytoplasmic antibody-associated vasculitis, and 50 (7%) had other RMDs. The number of SIEs recorded was 281 in 176 patients (9.8 per 100 person-years). Predictors of SIEs included non-RTX-specific comorbidities (previous history of SIE, cancer, chronic lung disease, diabetes mellitus, and heart failure), higher corticosteroid dose, and RTX-specific factors, including low IgG (<6 gm/liter) both at baseline and during treatment, RTX-associated neutropenia, higher IgM, and longer time to RTX re-treatment, but not B cell count or depletion status. Of 110 patients with low IgG, SIE rates were higher in those with low IgG at baseline (16.4 per 100 person-years) and in those who acquired low IgG during or after RTX treatment (21.3 per 100 person-years) versus those with normal IgG (9.7 per 100 person-years). Five of 8 patients (63%) had impaired humoral response to pneumococcus and hemophilus following vaccination challenge, and only 4 of 11 patients (36%) had IgG normalized after switching biologic disease-modifying antirheumatic drugs.

CONCLUSION

Immunoglobulin levels should be monitored at baseline and before each RTX cycle to identify patients at risk of SIEs. Individualized risk-benefit assessment should be undertaken in those with lower IgG as this is a consistent SIE predictor and may increase infection profiles when RTX is switched to different therapies.

State of Art of Idiosyncratic Drug-Induced Neutropenia or Agranulocytosis, with a Focus on Biotherapies

INTRODUCTION

Idiosyncratic drug-induced neutropenia and agranulocytosis is seldom discussed in the literature, especially for new drugs such as biotherapies outside the context of oncology. In the present paper, we report and discuss the clinical data and management of this relatively rare disorder, with a focus on biotherapies used in autoimmune and auto-inflammatory diseases.

MATERIALS AND METHODS

A review of the literature was carried out using the PubMed database of the US National Library of Medicine. We searched for articles published between January 2010 and May 2019 using the following key words or associations: "drug-induced neutropenia", "drug-induced agranulocytosis", and "idiosyncratic agranulocytosis". We included specific searches on several biotherapies used outside the context of oncology, including: tumor necrosis factor (TNF)-alpha inhibitors, anti-CD20 agents, anti-C52 agents, interleukin (IL) 6 inhibitors, IL 1 inhibitors, and B-cell activating factor inhibitor.

RESULTS

Idiosyncratic neutropenia remains a potentially serious adverse event due to the frequency of severe sepsis with severe deep tissue infections (e.g., pneumonia), septicemia, and septic shock in approximately two-thirds of all hospitalized patients with grade 3 or 4 neutropenia (neutrophil count (NC) ≤ 0.5 × 109/L and ≤ 0.1 × 109/L, respectively). Over the last 20 years, several drugs have been strongly associated with the occurrence of idiosyncratic neutropenia, including antithyroid drugs, ticlopidine, clozapine, sulfasalazine, antibiotics such as trimethoprim-sulfamethoxazole, and deferiprone. Transient grade 1-2 neutropenia (absolute blood NC between 1.5 and 0.5 × 109/L) related to biotherapy is relatively common with these drugs. An approximate 10% prevalence of such neutropenia has been reported with several of these biotherapies (e.g., TNF-alpha inhibitors, IL6 inhibitors, and anti-CD52 agents). Grade 3-4 neutropenia or agranulocytosis and clinical manifestations related to sepsis are less common, with only a few case reports to date for most biotherapies. Special mention should be made of late onset and potentially severe neutropenia, especially following anti-CD52 agent therapy. During drug therapy, several prognostic factors have been identified that may be helpful when identifying 'susceptible' patients. Older age (>65 years), septicemia or shock, renal failure, and a neutrophil count ≤0.1 × 109/L have been identified as poor prognostic factors. Idiosyncratic neutropenia should be managed depending on clinical severity, with permanent/transient discontinuation or a lower dose of the drug, switching from one drug to another of the same or another class, broad-spectrum antibiotics in cases of sepsis, and hematopoietic growth factors (particularly G-CSF).

CONCLUSION

Significant progress has been made in recent years in the field of idiosyncratic drug-induced neutropenia, leading to an improvement in their prognosis (currently, mortality rate between 5 and 10%). Clinicians must continue their efforts to improve their knowledge of these adverse events with new drugs as biotherapies.

Rituximab as Maintenance Treatment for Systemic Lupus Erythematosus: A Multicenter Observational Study of 147 Patients

OBJECTIVE

The efficacy of rituximab (RTX) in systemic lupus erythematosus (SLE) is a subject of debate. This study was undertaken to investigate the outcomes of RTX treatment in a European SLE cohort, with an emphasis on the role of RTX as a maintenance agent.

METHODS

All patients with SLE who were receiving RTX as induction therapy in 4 centers were included. Patients who received a single course of RTX and those who received RTX maintenance treatment (RMT) were followed up after treatment. Disease flares during the follow-up period were defined as an increase in disease activity and the number or dose of immunosuppressive drugs.

RESULTS

Of 147 patients, 27% experienced treatment failure at 6 months. In a multivariate analysis, a low number of previous immunosuppressive therapies (P = 0.034) and low C4 levels (P = 0.008) reduced the risk of treatment failure. Eighty patients received RMT over a median of 24.5 months during which 85 relapses, mainly musculoskeletal, were recorded (1.06 per patient). At the time of the last RTX course, 84% of the patients were in remission. Twenty-eight (35%) of 80 patients never experienced a flare during RMT and had low damage accrual. Active articular disease at the time of the first RTX administration was associated with a risk of flare during RMT (P = 0.011). After RMT, relapse-free survival was similar to that in patients receiving a single RTX course (P = 0.72).

CONCLUSION

RMT is a potential treatment option for patients with difficult-to-treat disease. Relapses occur during RMT and are more likely in those with active articular disease at the time of the first RTX administration. Relapse risk after RMT remains high and apparently comparable to that seen after a single RTX course.

Advances in Therapies and Imaging for Systemic Vasculitis

Vasculitis is a systemic disease characterized by immune-mediated injury of blood vessels. Current treatments for vasculitis, such as glucocorticoids and alkylating agents, are associated with significant side effects. Furthermore, the management of both small and large vessel vasculitis is challenging because of a lack of robust markers of disease activity. Recent research has advanced our understanding of the pathogenesis of both small and large vessel vasculitis, and this has led to the development of novel biologic therapies capable of targeting key cytokine and cellular effectors of the inflammatory cascade. In parallel, a diverse range of imaging modalities with the potential to monitor vessel inflammation are emerging. Continued expansion of combined structural and molecular imaging using positron emission tomography with computed tomography or magnetic resonance imaging may soon provide reliable longitudinal tracking of vascular inflammation. In addition, the emergence of radiotracers able to assess macrophage activation and immune checkpoint activity represents an exciting new frontier in imaging vascular inflammation. In the near future, these advances will allow more precise imaging of disease activity enabling clinicians to offer more targeted and individualized patient management.

Late-Onset Neutropenia after Rituximab Treatment for Adult-Onset Nephrotic Syndrome

A 41-year-old woman developed nephrotic syndrome at the age of 32 and was diagnosed with minimal change nephrotic syndrome based on a renal biopsy. Although remission was achieved with administration of prednisolone (PSL) and cyclosporine, the nephrotic syndrome recurred. She was also started on rituximab (RTX). She developed late-onset neutropenia after RTX treatment (R-LON) and improved 17 days later. Although the majority of R-LON cases undergo spontaneous remission, cases of death have been reported. This report is intended to warn about R-LON, since the use of RTX for adult-onset nephrotic syndrome is expected to increase in the future.

Rituximab in neurological disease: principles, evidence and practice

Rituximab is a widely used B-cell-depleting monoclonal antibody. It is unlicensed for use in neurological disorders and there are no treatment guidelines. However, as a rapidly acting, targeted therapy with growing evidence of efficacy and tolerability in several neuroinflammatory disorders, it is an attractive alternative to conventional immunomodulatory medications. This practical review aims to explain the basic principles of B-cell depletion with therapeutic monoclonal antibodies. We present the evidence for using rituximab in neurological diseases, and describe the practical aspects of prescribing, including dosing, monitoring, safety, treatment failure and its use in special circumstances such as coexisting viral hepatitis, pregnancy and lactation. We provide an administration guide, checklist and patient information leaflet, which can be adapted for local use. Finally, we review the safety data of rituximab and ocrelizumab (a newer and recently licensed B-cell-depleting therapy for multiple sclerosis) and suggest monitoring and risk reduction strategies.

Neutropaenia in early rheumatoid arthritis: frequency, predicting factors, natural history and outcome

Objectives

To determine the frequency, severity and natural history of neutropaenia in early rheumatoid arthritis (RA), explore its associations with clinical features and assess its impact on clinical management.

Methods

The Scottish Early Rheumatoid Arthritis inception cohort prospectively recruited patients with newly diagnosed RA and followed them up every 6 months. Patients with RA who developed at least one episode of neutropaenia (grade 1: <2.0×10^9/L; grade 2: <1.5×10^9/L; grade 3: <1.0×10^9/L; grade 4: <0.5×10^9/L) were compared with those who did not. Comparisons were also made between patients who experienced one or more episodes of neutropaenia and between patients with different neutropaenia grades.

Results

77 neutropaenia episodes were recorded in 58 of 771 (7.5%) patients with RA, who were followed up for a median (range) of 18 (6-48) months. Neutropaenia occurred at a median (range) of 12 (0-120) months after RA diagnosis. The majority had mild neutropaenia (grade 1: n=42; grade 2: n=14; grade 3: n=1; grade 4: n=1). Neutropaenia was transient (single episode) in the majority (44; 75.8%) of cases but led to treatment discontinuation in 14 (24.1%) patients. Patients who developed neutropaenia were more likely to be female (p=0.01) and non-smokers (p=0.007) and had lower baseline neutrophil levels (p<0.0001). Binomial regression analysis confirmed the latter (p<0.0001, B: -0.491) as neutropaenia predictor. The rate of infections did not differ between patients who developed neutropaenia and those who did not (p=0.878).

Conclusion

Neutropaenia was a common finding in this cohort. It was usually mild, transient and not associated with increased infection rates. Neutropaenia occurrence was associated with non-smoking, female gender and lower baseline neutrophil levels.

Stratification of Systemic Lupus Erythematosus Patients Into Three Groups of Disease Activity Progression According to Longitudinal Gene Expression

OBJECTIVE

The highly heterogeneous clinical presentation of systemic lupus erythematosus (SLE) is characterized by the unpredictable occurrence of disease flares and organ damage. Attempts to stratify lupus patients have been limited to classification based on clinical information, leading to unsuccessful clinical trials and controversial research results. This study was undertaken to develop and validate a robust method to stratify patients with lupus according to longitudinal disease activity and whole-genome gene expression data in order to establish subgroups of patients who share disease progression mechanisms.

METHODS

We used a cluster-based approach to stratify SLE patients based on the correlation between disease activity scores and longitudinal gene expression information. Clustering robustness was evaluated by the bootstrap method, and the clusters were characterized in terms of clinical and functional features.

RESULTS

We observed a clear partition into 3 different disease clusters in 2 independent sets of patients, one pediatric and one adult, which was not influenced by treatment, race, or other source of bias. Two of the clusters differentiated into a group showing a correlation between the percentage of neutrophils and disease activity progression and a group showing a correlation between the percentage of lymphocytes and disease activity progression. The third cluster, in which the percentage of neutrophils correlated to a lesser degree with disease activity, was functionally more heterogeneous. Patients in the neutrophil-driven clusters had an increased risk of developing proliferative nephritis.

CONCLUSION

Our findings indicate that SLE patients can be stratified into 3 subgroups of patients who show different mechanisms of disease progression and are clinically differentiated. Our results have important implications for treatment options, the design of clinical trials, our understanding of the etiology of the disease, and the prediction of severe glomerulonephritis.

Rituximab-mediated late-onset neutropenia in systemic lupus erythematosus – distinct roles of BAFF and APRIL

Objective

Rituximab-mediated late-onset neutropenia (LON) has been described in various diseases. We investigated its occurrence, consequences and contributing factors in patients with systemic lupus erythematosus (SLE).

Methods

Rituximab-treated patients from the Karolinska University Hospital ( n = 107) were surveyed. LON was defined as an absolute neutrophil count <1500 cells/μl, occurring four weeks to two years following rituximab treatment, or later during sustained B-cell depletion. Serum levels of B-cell-related cytokines and growth factors of the myeloid lineage were determined using enzyme-linked immunosorbent assay.

Results

Thirty-two patients (29.9%) developed LON after a median time of 201.5 days. Thirteen patients were admitted to the hospital; 10 due to fever. Three patients developed critical conditions. BAFF levels increased from baseline (median: 0.62 ng/ml) to the post-treatment evaluation (median: 1.16 ng/ml; p < 0.001); post-treatment levels were higher in the LON group ( p = 0.021). APRIL levels were higher in the LON group both at baseline (median: 1.54 versus 1.15 ng/ml; p = 0.027) and post-treatment (median: 2.39 versus 1.11 ng/ml; p = 0.011). IL-6 and GM-CSF levels decreased in the non-LON group ( p < 0.001), but not in LON patients. High baseline disease activity predicted LON development (OR: 4.1; 95% CI: 1.1–15.2 for SLEDAI-2K > 8). No association with neutropenia prior to rituximab treatment was documented.

Conclusion

Post-rituximab LON was a common complication. Although the phenomenon was predominantly self-limiting, several patients developed severe conditions. Distinct roles of BAFF and APRIL are implicated: BAFF may contribute to LON development, whereas high APRIL levels may be predictive. Rituximab-treated SLE patients should be monitored for neutrophil counts, fever and infections.

Late-onset neutropenia and neurological relapse, during long-term rituximab therapy in myelin oligodendrocyte glycoprotein-antibody spectrum disorder

Late-onset neutropenia after rituximab therapy (LONART) is defined as a fall in the absolute neutrophil count below 500/mm3 at least 3 weeks after rituximab infusion, in the absence of any other explanation. LONART is rare during dysimmune conditions but can be life-threatening. We report on two patients with LONART and associated neurological relapse occurring in myelin oligodendrocyte glycoprotein (MOG)-antibody spectrum disorders. Rituximab was reintroduced in one patient, while the second patient was switched to tocilizumab. LONART can occur during anti-MOG spectrum disorders. Neurologists should be aware of this rare and treatable complication. Regular monitoring of blood cell counts is needed, and patients should be informed of the need to consult their physician if symptoms of infection appear.

Cancer chemotherapeutics in rheumatoid arthritis: A convoluted connection

Chemotherapy is one of the most popular therapeutic strategies to treat cancer. However, cancer chemotherapeutics have often been associated with impairment of the immune system, which might consequently lead to an augmented risk of autoimmune disorders, such as rheumatoid arthritis. Though the accurate mechanistic facets of rheumatoid arthritis induction have not been interpreted yet, a conglomeration of genetic and environmental factors might promote its etiology. What makes the scenario more challenging is that patients with rheumatoid arthritis are at a significantly elevated risk of developing various types of cancer. It is intriguing to note that diverse cancer chemotherapy drugs are also commonly used to treat symptoms of rheumatoid arthritis. However, a colossal multitude of such cancer therapeutics has demonstrated highly varied results in rheumatoid arthritis patients, including both beneficial and adverse effects. Herein, we attempt to present a holistic account of the variegated modalities of this complex tripartite cross-talk between cancer, rheumatoid arthritis and chemotherapy drugs in order to decode the sinuous correlation between these two appalling pathological conditions.

Epstein-barr virus DNAemia monitoring for the management of post-transplant lymphoproliferative disorder

BACKGROUND

Post-transplant lymphoproliferative disorder (PTLD) is a potentially fatal complication of allogeneic hematopoietic cell transplantation (HCT). Epstein-Barr virus (EBV) reactivation (detectable DNAemia) predisposes to the development of PTLD.

METHODS

We retrospectively studied 306 patients monitored for EBV DNAemia after Thymoglobulin-conditioned HCT to determine the utility of the monitoring in the management of PTLD. DNAemia was monitored weekly for ≥12 weeks post-transplantation.

RESULTS

Reactivation was detected in 82% of patients. PTLD occurred in 14% of the total patients (17% of patients with reactivation). PTLD was treated with rituximab only when and if the diagnosis was established. This allowed us to evaluate potential DNAemia thresholds for pre-emptive therapy. We suggest 100,000-500,000 IU per mL whole blood as this would result in unnecessary rituximab administration to only 4-20% of patients and near zero mortality due to PTLD. After starting rituximab (for diagnosed PTLD), sustained regression of PTLD occurred in 25/25 (100%) patients in whom DNAemia became undetectable. PTLD progressed or relapsed in 12/17 (71%) patients in whom DNAemia was persistently detectable.

DISCUSSION

In conclusion, for pre-emptive therapy of PTLD, we suggest threshold DNAemia of 100,000-500,000 IU/mL. Persistently detectable DNAemia after PTLD treatment with rituximab appears to have 71% positive predictive value and 100% negative predictive value for PTLD progression/relapse.

Rituximab and lenalidomide combination treatment for rheumatoid arthritis complicated with myelodysplastic syndrome: A case report

Rheumatoid arthritis patients might experience several hematologic complications. The development of myelodysplastic syndrome is not clearly associated with RA, even though it has been described in some patients with pre-existing disease. There are only few data available in the literature concerning the therapeutic approach of such patients. Herein, we report a case of RA complicated with progressive MDS, successfully treated with rituximab and lenalidomide combination therapy.

Severe neutropenia after rituximab-treatment of multiple sclerosis

We present here the first MS-case where rituximab-treatment led to grade IV neutropenia, with hospitalization and treatment of a serious infection with broad-spectrum antibiotics. The neutropenia resolved promptly with granulocyte-colony stimulating factor-treatment and the patient recovered well. Due to risk of recurring neutropenia rituximab-treatment was not re-administered. We discuss the mechanisms and occurrence of neutropenia as a side effect to rituximab-treatment of MS, and remind of the importance of monitoring rituximab-treated MS-patients for this rare but potentially dangerous side effect.

Review of Routine Laboratory Monitoring for Patients with Rheumatoid Arthritis Receiving Biologic or Nonbiologic DMARDs

Safety concerns associated with many drugs indicated for the treatment of rheumatoid arthritis (RA) can be attenuated by the early identification of toxicity through routine laboratory monitoring; however, a comprehensive review of the recommended monitoring guidelines for the different available RA therapies is currently unavailable. The aim of this review is to summarize the current guidelines for laboratory monitoring in patients with RA and to provide an overview of the laboratory abnormality profiles associated with each drug indicated for RA. Recommendations for the frequency of laboratory monitoring of serum lipids, liver transaminases, serum creatinine, neutrophil counts, and platelet counts in patients with RA were compiled from a literature search for published recommendations and guidelines as well as the prescribing information for each drug. Laboratory abnormality profiles for each drug were compiled from the prescribing information for each drug and a literature search including meta-analyses and primary clinical trials data.

Zytopenien

Hematological alterations can often be observed during rheumatic diseases. The effects can be clinically severe, ranging from anemia of different grades of severity, through increased risk of hemorrhage due to thrombocytopenia up to severe infections as a result of high-grade leukocytopenia. The clinical sequelae for patients are predominantly determined by the extent of cytopenia. The underlying disease itself can initially be considered as the cause. Examples are anemia as a result of chronic inflammation, antibody-mediated thrombocytopenia as in systemic lupus erythematosus (SLE) or granulocytopenia within the framework of Felty's syndrome. Immunosuppressive treatment also often leads to alterations in the blood constituents. Although some substances, such as cyclophosphamide can suppress all three cell types, there are also selective effects, such as isolated thrombocytopenia under treatment with tocilizumab and JAK inhibitors. The differential diagnostic clarification of cytopenia can be difficult and necessitates a systematic work-up of the course of the disease and the subsequent treatment. The reviews of anemia, leukocytopenia and thrombocytopenia presented here summarize the most important components of the differentiation of hematological alterations in patients with rheumatic diseases.

Treatment of Juvenile Dermatomyositis: An Update

The idiopathic inflammatory myopathies of childhood consist of a heterogeneous group of autoimmune diseases characterised by proximal muscle weakness and pathognomonic skin rashes. The overall prognosis of juvenile myositis has improved significantly over recent years, but the long-term outcome differs substantially from patient to patient, suggestive of distinct clinical phenotypes with variable responses to treatment. High doses of corticosteroids remain the cornerstone of therapy along with other immunosuppressant therapies depending on disease severity and response. The advent of biological drugs has revolutionised the management of various paediatric rheumatologic diseases, including inflammatory myopathies. There are few data from randomised controlled trials to guide management decisions; thus, several algorithms for the treatment of juvenile myositis have been developed using international expert opinion. The general treatment goals now include elimination of active disease and normalisation of physical function, so as to preserve normal growth and development, and to prevent long-term damage and deformities. This review summarises the newer and possible future therapies of juvenile inflammatory myopathies, including evidence supporting their efficacy and safety.

Neutropenia in the Elderly: A Rheumatology Perspective

The majority of rheumatic diseases are chronic and require long-term use of disease-modifying agents to confer the best chance of controlling the disease. A significant proportion of these drugs have a risk, albeit small, of potentially serious side effects, such as neutropenia; therefore, there has been an understandable concern over the use of potentially toxic rheumatic drugs in the elderly. Factors that may contribute to this concern include age, pre-existing co-morbidities, polypharmacy, difficulty in monitoring side effects, and patient perception. The risk of using such medication needs to be balanced with their benefits in controlling chronic disease. This review discusses how rheumatic disease and anti-rheumatic medication are associated with neutropenia in an older age group. Of the rheumatic diseases, we give special focus to rheumatoid arthritis and the use of methotrexate, as well as touching on management considerations in neutropenia.

Infectious complications of rituximab therapy in renal disease

Rituximab, an anti-CD20 monoclonal antibody, was originally used to treat B-cell malignancies. Its use has significantly increased in recent years, as it is now also used to treat a variety of autoimmune diseases including rheumatoid arthritis and ANCA-associated vasculitis (AAV). Initial studies suggested that the adverse effects of rituximab were minimal. Though the risk of malignancy with rituximab-based immunosuppressive regimens appears similar to that of the general population, there are now concerns regarding the risk of infectious complications. Rituximab has been associated with serious infections, including Pneumocystis jiroveci pneumonia (PJP) and the reactivation of hepatitis B virus (HBV) and tuberculosis (TB). The risk of infection appears to be the result of a variety of mechanisms, including prolonged B-cell depletion, B-cell–T-cell crosstalk, panhypogammaglobulinaemia, late-onset neutropenia and blunting of the immune response after vaccination. Importantly, the risk of infectious complications is also related to individual patient characteristics and the indication for rituximab. Individualization of treatment is, therefore, crucial. Particular attention should be given to strategies to minimize the risk of infectious complications, including vaccinating against bacterial and viral pathogens, monitoring white cell count and immunoglobulin levels, prophylaxis against PJP and screening for HBV and TB.

Rituximab for immunologic renal disease: What the nephrologist needs to know

Rituximab (RTX), a chimeric, monoclonal anti-CD20 antibody, is increasingly used in immune-mediated renal diseases. While licensed in the induction treatment of ANCA-associated vasculitis, it represents one of the most commonly prescribed off-label drugs. Much of the information regarding its safety has been drawn from experience in hematology and rheumatology. Ample evidence illustrates the safety of RTX, however, rare but serious adverse events have emerged that include progressive multifocal leucoencephalopathy and hepatitis B reactivation. Moderate to severe hypogammaglobulinemia and late-onset neutropenia following RTX therapy confer an increased infectious risk and factors predicting these side effects (i.e. a genetic basis) need to be identified. Nephrologists initiating RTX need to bear in mind that long-term risks and optimal dosing for many renal indications remain unclear. Special considerations must be given when RTX is used in women of childbearing age. We summarize practical aspects concerning the use of RTX. This review will provide nephrologists with information to guide their use of RTX alerting them to safety risks and the need for patient counselling.

Effect of FCGR polymorphism on the occurrence of late-onset neutropenia and flare-free survival in rheumatic patients treated with rituximab

Background

The causes and mechanisms of late-onset neutropenia (LON) following rituximab treatment in patients with rheumatic diseases are not known. In this study, we aimed to investigate the role of established Fcγ receptor gene (FCGR) polymorphisms and B-cell-activating factor (BAFF) gene promoter polymorphisms for the development of LON and for the efficacy of rituximab in patients with rheumatic diseases.

Methods

A single-center case-control retrospective study was nested in a cohort of 214 consecutive patients with rheumatic diseases treated with rituximab. Eleven patients presented with LON. Fifty non-LON control subjects were matched by diagnosis, age, sex, and treatments. Single-nucleotide polymorphisms of FCGR (FCGR2A 131H/R, FCGR2B 232I/T, FCGR3A 158V/F) and BAFF promoter polymorphism −871C/T were analyzed with polymerase chain reaction-based techniques, and serum immunoglobulin M (IgM) and BAFF levels were analyzed by enzyme-linked immunosorbent assay. Flare-free survival was related to LON occurrence and polymorphisms.

Results

The FCGR3A V allele, but not other FCGR polymorphisms, correlated with the occurrence of LON; each V allele conferred a fourfold increased OR for LON (p = 0.017). FCGR3A 158V/V and presentation with LON were associated with a longer flare-free survival (p = 0.023 and p = 0.031, respectively). FCGR3A 158V/V was related to lower IgM levels (p = 0.016). Serum BAFF levels showed no relationship with LON and BAFF −871C/T promoter polymorphism. There was a tendency toward longer flare-free survival in patients with the BAFF −871T/T allotype compared with the C/T or C/C allotypes (p = 0.096).

Conclusions

The results of the present study suggest that presentation with LON may be a result of the intrinsic efficacy of rituximab in patients with rheumatic diseases. LON could indicate a longer biological and therapeutic activity of rituximab modulated by a certain genotypic polymorphism: the high-affinity FCGR3A V allele. This genotype and the occurrence of LON are both related to longer flare-free survival, suggestive of common mechanisms for LON and duration of response to rituximab. The role of the BAFF −871C/T promoter polymorphism in LON occurrence is unclear.

Drug-Induced Neutropenia: A Focus on Rituximab-Induced Late-Onset Neutropenia

Rituximab can cause late-onset neutropenia that may result in serious life-threatening complications. The author describes the pathophysiology, incidence, and management of this adverse reaction and presents two case histories.

Agranulocytosis under biotherapy in rheumatoid arthritis: three cases hypothesis of parvovirus B19 involvement in agranulocytosis observed under tocilizumab and rituximab for the treatment of rheumatoid arthritis

Leukopenia is a considerably common complication of tocilizumab [TCZ] and rituximab [RTX] therapy. RTX-induced leukopenia typically exhibits delayed onset. While agranulocytosis has been reported linked to RTX treatment of lymphoma, this complication rarely occurs in rheumatoid arthritis (RA) treatment and, to our knowledge, has never been reported in association with TCZ therapy. We herein report four agranulocytosis cases in three patients, with the first two cases suspected to be secondary to human parvovirus B19 (PVB19) infection. Agranulocytosis manifested in the first patient 2 months following a third RTX course. Bone marrow (BM) polymerase chain reaction (PCR) was positive for PVB19. The patient relapsed after three TCZ courses, with her PCR again positive for PVB19. Both episodes resolved under granulocyte-macrophage colony-stimulating factor (GM-CSF). In the second patient, agranulocytosis manifested after the 74th TCZ course. Bone marrow PCR was positive for PVB19, and the evolution was favorable under intravenous immunoglobulin administration. The third case was a 53-year-old female patient with seropositive RA who presented agranulocytosis after the first infusion of her fourth RTX course. Unfortunately, no PCR PVB19 was made on myelogram. Evolution was favorable after 5 days of GM-CSF. PVB19 infection should be investigated in patients suffering from agranulocytosis manifesting during biotherapy. In cases manifesting from the 15th day of RTX treatment onwards, hemogram must be conducted before readministering the infusion.

Rituximab in autoimmune diseases

Rituximab is a monoclonal antibody that depletes B cells from the circulation. It was originally used to treat lymphoma but is increasingly used for the treatment of autoimmune diseases. Rituximab was found to be effective in randomised controlled trials for rheumatoid arthritis, granulomatosis with polyangiitis and other antineutrophil cytoplasmic antibody-associated vasculitides. However, evidence of efficacy is very limited for many other autoimmune conditions. Before starting rituximab, it is important to check the patient's baseline immunoglobulins and immunisation status. Patients should also be screened for latent infections and other contraindications.