Update on the Application of Monoclonal Antibody Therapy in Primary Membranous Nephropathy

When first introduced, rituximab (RTX), a chimeric anti-CD20 monoclonal antibody, brought about an alternative therapeutic paradigm for primary membranous nephropathy (PMN). Rituximab was shown to be effective and safe in PMN patients with kidney dysfunction, with. patients receiving second-line rituximab therapy achieving remission as effectively as those patients who had not previously received immunotherapy. No safety issues were reported. The B cell-driven protocol seems to be as efficient as the 375 mg/m² × 4 regimen or 1 g × 2 regimen in achieving B cell depletion and remission, but patients with high M-type phospholipase A2 receptor (PLA2R) antibody levels may benefit from a higher dose of rituximab. While rituximab added another therapeutic option to the treatment regimen, it does have limitations as 20 to 40% of patients do not respond. Not all patients respond to RTX therapy for lymphoproliferative disorders either, therefore further novel anti-CD20 monoclonal antibodies have been developed and these may provide alternative therapeutic options for PMN. Ofatumumab, a fully human monoclonal antibody, specifically recognizes an epitope encompassing both the small and large extracellular loops of the CD20 molecule, resulting in increased complement-dependent cytotoxic activity. Ocrelizumab binds an alternative but overlapping epitope region to rituximab and displays enhanced antibody-dependent cellular cytotoxic (ADCC) activities. Obinutuzumab is designed to have a modified elbow-hinge amino acid sequence, leading to increased direct cell death induction and ADCC activities. In PMN clinical studies, ocrelizumab and obinutuzumab showed promising results, while ofatumumab displayed mixed results. However, there is a lack of randomized controlled trials with large samples, especially direct head-to-head comparisons. Alternative molecular mechanisms have been suggested in this context to explore novel therapeutic strategies. B cell activator-targeted, plasma cell-targeted and complement-directed treatments may lead to novel therapy paradigms for PMN. Exploratory strategies for the use of drugs with different mechanisms, such as a combination of rituximab and cyclophosphamide and a steroid, a combination of rituximab and a calcineurin inhibitor, may provide more rapid and efficient remission, but the combination of standard immunosuppression with rituximab could increase infection risk.

Atrial Fibrillation in Cancer Patients: Who is at Risk?

Cancer is the second leading cause of mortality in the world, second only to cardiovascular diseases. Simultaneously cancer mortality has been steadily decreasing due to the development  of new chemotherapy and targeted  drugs  and the improvement  of existing  treatment protocols.  Improving the prognosis of treatment of cancer patients leads to an unexpected  result - more patients are faced with side effects of cancer treatment. Cardiotoxicity, including  arrhythmia, has  become  a significant  factor  to reduce  the effectiveness  of cancer  patient’s  treatment.  Atrial  fibrillation  is frequent  and persistent a rhythm disorder, affecting  all categories  of patients, especially the elderly. An association  between these two conditions  can be expected, considering the fact that in old age the prevalence of malignant neoplasms  and comorbid pathology predisposing to the onset of AF is high. Therefore, AF may be an additional  factor negatively  influencing the prognosis and treatment tactics in patients with malignant neoplasms. A comprehensive search was conducted  using the keywords  “cancer”, “atrial fibrillation” and “cardiotoxicity” using the PubMed,  Scopus and Cohrane  databases. We reviewed publications having the relationship between AF and cancer. The literature review considered 61 publications on the prevalence of AF in cancer patients, classification, mechanisms of development, the effect of anticancer drugs and other treatment methods on this group of patients. Analyzed articles include clinical guidelines, consensus  expert opinions,  systematic  reviews,  meta-analyzes, and previously  published  reviews of the literature. The problem of cardiotoxic  complications diagnostics is evaluated separately,  incl. arrhythmias, and their monitoring in cancer patients. Therefore, the direction of medicine named "Cardio-oncology" comes to the fore. Interdisciplinary interaction will allow identify cardiotoxic  manifestations at the subclinical stage and optimize anticancer treatment.

Recommendations for managing the manifestations of severe and life-threatening mixed cryoglobulinemia syndrome

OBJECTIVE

Some of the manifestations of mixed cryoglobulinemia syndrome (MCS) can be severe or life-threatening, and should be rapidly contained but, as the therapeutic approaches to such conditions are largely based on anecdotal data, a consensus conference was organised by the Italian Group for the Study of Cryoglobulinemia (GISC) with the aim of providing a set of recommendations based on an in-depth survey of the available data and expert opinion.

METHODS

The consensus panel, which included specialists working in different medical fields involved in the management of MCS patients, was first asked to divide the manifestations of MCS into severe or life-threatening conditions on the basis of their own experience, after which a complete literature review was carried out in accordance with the Cochrane guidelines for systematic reviews.

RESULTS

Therapeutic plasma exchange (TPE) was considered the elective first-line treatment in the case of life-threatening manifestations of MCS (LT-MCS) and patients with severe clinical symptoms (S-MCS) who fail to respond to (or who are ineligible for) other treatments. The data supporting the combined use of cyclophosphamide and TPE were considered limited and inconclusive. High-dose pulsed glucocorticoid (GCS) therapy can be considered the first-line treatment of severe MCS, generally in association with TPE. Rituximab (RTX)-based treatments should be considered in patients with skin ulcers, peripheral neuropathy or glomerulonephritis, and in patients with persistent LT-MCS after TPE. In patients with hepatitis C virus-related MCS with S-MCS, viral eradication should be attempted as soon as a patient's condition allows the use of direct-acting antivirals.

Anticancer drugs-related QTc prolongation, torsade de pointes and sudden death: current evidence and future research perspectives

Anticancer drugs may have proarrhythmic effects including drug-induced QT interval prolongation, which is of particular importance because it can lead to a fatal polymorphic ventricular tachycardia termed torsade de pointes (TdP). QT interval prolongation and TdP are rare life-threatening untoward effects of anticancer therapy, particularly with arsenic trioxides and anthracyclines, and even some novel molecular targeted drugs touted as 'tumor specific'. Several factors that affect myocardial repolarization can further increase the risk of TdP. This article reviews the mechanism of QT interval prolongation, risk factors for TdP and the QT toxicity of anticancer drugs as well as its management. Specific attention should be paid to high-risk populations such as patients with underlying heart diseases, electrolyte imbalance and bradycardia. To minimize the occurrence of QT interval prolongation and TdP, it is advisable to conduct a careful risk factor assessment before antitumor therapy. To this end, several new biomarkers have been introduced to predict TdP triggering and recent studies have pointed out the potential clinical relevance of genetic testing.

Anticancer drug-induced cardiac rhythm disorders: Current knowledge and basic underlying mechanisms

Significant advances in cancer treatment have resulted in decreased cancer related mortality for many malignancies with some cancer types now considered chronic diseases. Despite these improvements, there is increasing recognition that many cancer patients or cancer survivors can develop cardiovascular diseases, either due to the cancer itself or as a result of anticancer therapy. Much attention has focused on heart failure; however, other cardiotoxicities, notably cardiac rhythm disorders, can occur without underlying cardiomyopathy. Supraventricular tachycardias occur in cancer patients treated with cytotoxic chemotherapy (anthracyclines, gemcitabine, cisplatin and alkylating-agents) or kinase-inhibitors (KIs) such as ibrutinib. Ventricular arrhythmias, with a subset of them being torsades-de-pointes (TdP) favored by QTc prolongation have been reported: this may be the result of direct hERG-channel inhibition or a more recently-described mechanism of phosphoinositide-3-kinase inhibition. The major anticancer drugs responsible for QTc prolongation in this context are KIs, arsenic trioxide, anthracyclines, histone deacetylase inhibitors, and selective estrogen receptor modulators. Anticancer drug-induced cardiac rhythm disorders remain an underappreciated complication even by experienced clinicians. Moreover, the causal relationship of a particular anticancer drug with cardiac arrhythmia occurrence remains challenging due in part to patient comorbidities and complex treatment regimens. For example, any cancer patient may also be diagnosed with common diseases such as hypertension, diabetes or heart failure which increase an individual's arrhythmia susceptibility. Further, anticancer drugs are generally usually used in combination, increasing the challenge around establishing causation. Thus, arrhythmias appear to be an underappreciated adverse effect of anticancer agents and the incidence, significance and underlying mechanisms are now being investigated.

Biologic drugs and arrhythmic risk in chronic inflammatory arthritis: the good and the bad

Increasing evidence indicates that patients with chronic inflammatory arthritis (CIA), including rheumatoid arthritis and spondyloarthropathies, have an increased risk of arrhythmic events, significantly contributing to the higher cardiovascular disease (CVD) morbidity and mortality observed in these subjects compared to the general population. Although the mechanisms accounting for such an arrhythmogenic substrate are not fully understood, the main role is probably played by chronic systemic inflammation, able to accelerate the development of structural CVD, as well as to directly affect cardiac electrophysiology. In the past decade, biologic therapies have revolutionized the treatment of CIA by highly enhancing the probability to effectively control disease activity and its systemic consequences, including cardiovascular involvement. Accordingly, accumulating data demonstrated that by potently inhibiting systemic inflammation, biologic drugs can reduce CVD progression and ameliorate arrhythmic risk parameters, with a putative beneficial impact on arrhythmia incidence. Nevertheless, a significant number of reports from clinical trials and postmarketing experience suggest that some of these medications, particularly TNF inhibitor monoclonal antibodies and rituximab, may in some circumstances precipitate arrhythmia occurrence, probably by acutely amplifying myocardial electric instability intrinsically associated with these diseases. In this review, we analyze the intricate link between biologic drugs and arrhythmias in CIA in the effort to identify which factors are involved in the fine-tuning of antiarrhythmic/pro-arrhythmic balance, and understand how this knowledge should be translated in the clinical practice to obtain the most favorable benefit-to-risk profile when biologic drugs are used in these patients.

Illuminating drug action by network integration of disease genes: a case study of myocardial infarction

Drug discovery has produced many successful therapeutic agents; however, most of these drugs were developed without a deep understanding of the system-wide mechanisms of action responsible for their indications. Gene-disease associations produced by molecular and genetic studies of complex diseases provide great opportunities for a system-level understanding of drug activity. In this study, we focused on acute myocardial infarction (MI) and conducted an integrative network analysis to illuminate drug actions. We integrated MI drugs, MI drug interactors, drug targets, and MI disease genes into the human interactome and showed that MI drug targets are significantly proximate to MI disease proteins. We then constructed a bipartite network of MI-related drug targets and MI disease proteins and derived 12 drug-target-disease (DTD) modules. We assessed the biological relevance of these modules and demonstrated the benefits of incorporating disease genes. The results indicate that DTD modules provide insights into the mechanisms of action of MI drugs and the cardiovascular (side) effects of non-MI drugs.

Cardiovascular risk and the use of biologic agents in rheumatoid arthritis

Although patients with rheumatoid arthritis (RA) are recognized to be disproportionately impacted by cardiovascular disease (CVD), effective approaches of primary and secondary CVD prevention have not been well defined in this population. Given their robust disease-modifying potential and effects on both pro-inflammatory and pro-atherogenic pathways, there has been substantial speculation that biologic treatments may serve as a means of providing highly effective RA disease control while simultaneously reducing CVD risk in this high risk group. In this review, we examine available evidence relevant to the associations of approved biologic treatments with CVD outcomes in the context of RA.