Being an ADVOCATE for People with ANCA Vasculitis

Targeting complement in kidney transplantation: Therapeutic approaches based on preclinical and experimental evidence

The complement system is implicated in various facets of kidney transplantation, including ischemia-reperfusion injury (IRI), delayed graft function, allograft rejection, and chronic allograft injury. IRI, prevalent in cadaveric renal transplantation, leads to acute tubular necrosis and engages innate immunity, including neutrophils and the complement system, fostering a cycle of inflammation and necrosis. Experimental and preclinical evidence suggest that targeting the complement system could offer therapeutic benefits in IRI during kidney transplantation. This article explores potential therapeutic approaches targeting complement pathways in kidney transplantation, drawing from experimental and preclinical research findings.

Avacopan as an add-on therapy for ANCA-associated vasculitis: a pharmacological overview

INTRODUCTION

ANCA-associated vasculitis (AAV) is a rare, life-threatening disease which may result in serious pulmonary and kidney damage. Cyclophosphamide or rituximab and high-dose glucocorticoids significantly improved patient outcomes, but at the expense of severe complications. Moreover, many patients still relapse and bear a significant burden of both disease- and treatment-related complications. Alternative complement pathway and C5a receptor signaling were demonstrated to play an important role in AAV pathogenesis. Avacopan is selective C5a receptor inhibitor successfully tested in renal AAV as glucocorticoid-sparing agent.

AREAS COVERED

Pharmacokinetic/pharmacodynamic properties, clinical efficacy and safety of avacopan, available clinical trials and real-world experience with avacopan.

EXPERT OPINION

In the phase 3 trial avacopan was shown to be non-inferior at six and superior at 12 months compared to high-dose glucocorticoids and either cyclophosphamide or rituximab in patients with active AAV. Treatment with avacopan was well tolerated and associated with improved quality of life. In patients with severe renal AAV, renal function improved more in avacopan-treated than in high-dose glucocorticoid-treated patients. Avacopan could thus replace high-dose glucocorticoids to avoid glucocorticoid-related toxicity and to improve long term renal outcome. As avacopan is CYP 3A4 inhibitor and substrate, drug-drug interactions must be considered during the treatment.

Avacopan's potential to decrease MPO-ANCA titres concurrent with ameliorated activity in ANCA-associated vasculitis

Avacopan, an orally administered C5a receptor antagonist, is effective in microscopic polyangiitis via the inhibition of neutrophil priming induced by C5a. However, the exact effect of avacopan on the production of myeloperoxidase antineutrophil cytoplasmic antibody (MPO-ANCA) is yet to be clearly established. This report presents a microscopic polyangiitis patient without major organ damage where high levels of MPO-ANCA persisted with high-dose steroid therapy and azathioprine, but the addition of avacopan led to a reduction in MPO-ANCA titres. The present case implies that avacopan-mediated inhibition of C5a may lead to a reduction in MPO-ANCA levels, thereby potentially ameliorating the pathophysiology of ANCA-associated vasculitis. Nevertheless, the impact of avacopan on MPO-ANCA production cannot be asserted solely based on this report; therefore, further examination is necessary through subgroup analysis using data from larger-scale studies.

Recent Advancements in the Management of Anti-neutrophil Cytoplasmic Antibody-Associated Vasculitis: A Systematic Review

Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is a rare multisystem autoimmune condition that causes inflammation of small and medium-sized blood vessels and is more commonly seen in the geriatric population. ANCA-associated vasculitis (AAV) is typically characterized as necrotizing vasculitis and includes granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). The mortality rate remains high, with especially cardiovascular disease, infections, and malignancies being the leading causes of death. Existing treatment options depend heavily on the use of glucocorticoids (GCs), often in combination with cyclophosphamide (CYC); however, as the multitude of adverse effects associated with these agents has increased, numerous studies are being conducted to reduce not only these harmful effects but also improve remission rates. Rituximab, avacopan, corticosteroids, including intravenous pulse methylprednisolone, plasma exchange, and immunological targeting are among the emerging treatments. The purpose of this review is to emphasize the pathogenesis and traditional treatment modalities and give insights into the recent advances in managing this disorder in an attempt to spare the adverse effects of conventional therapies while achieving better remission rates with combination therapies as well. The authors explored multiple databases, employing appropriate keywords, satisfying the quality appraisal, after which a total of 14 reports were included in this review. Upon overall analysis, it can be concluded that rituximab and CYC, when used in combination, provided a safer alternative to GCs while exhibiting equal, if not superior, effectiveness and results, thus, paving the way for additional in-depth research in a larger population of interest.