Targeting the Roots of Kidney Disease: Systematic Review of the Therapies Targeting the Complement System

Background/Objectives: The field of nephrology is increasingly embracing advanced treatments and clinical trials that focus on inhibiting specific components of the complement cascade, a key driver in complement-mediated kidney diseases. Materials and Methods: This review aims to summarize innovative therapies targeting various pathways, including the inhibition of the terminal part of the complement pathway (mainly C5), the alternative pathway (factor B inhibitors), and the lectin pathway (MASP inhibitors. C5 inhibitors play a critical role in preventing the formation of the membrane attack complex (MAC), offering effective solutions for conditions like atypical hemolytic uremic syndrome (aHUS) and paroxysmal nocturnal hemoglobinuria (PNH). Meanwhile, avacopan, a C5a receptor antagonist, addresses ANCA-associated vasculitis (AAV) by mitigating inflammation and enabling reduced reliance on corticosteroids. Similarly, narsoplimab, which inhibits MASP-2, targets the lectin pathway implicated in conditions such as aHUS. Iptacopan, a factor B inhibitor, focuses on the alternative pathway and demonstrates efficacy in managing C3 glomerulopathy (C3G). Results: A systematic review of complement-targeted therapies was conducted, analysing studies from 2013 to 2023 that address unmet medical needs in primary and secondary glomerular diseases. Conclusions: Our systematic review of complement-targeted therapies shows that these tailored and innovative treatments may specifically address unmet medical needs in primary and secondary glomerular diseases.