Endothelin receptor antagonists in kidney protection for diabetic kidney disease and beyond?

Drug repurposing for glomerular diseases: an underutilized resource

Drug repurposing in glomerular disease can deliver opportunities for steroid-free regimens, enable personalized multi-target options for resistant or relapsing disease and enhance treatment options for understudied populations (for example, children) and in resource-limited settings. Identification of drug-repurposing candidates can be data driven, which utilizes existing data on disease pathobiology, drug features and clinical outcomes, or experimental, which involves high-throughput drug screens. Information from databases of approved drugs, clinical trials and PubMed registries suggests that at least 96 drugs on the market cover 49 targets with immunosuppressive potential that could be candidates for drug repurposing in glomerular disease. Furthermore, evidence to support drug repurposing is available for 191 immune drug target-glomerular disease pairs. Non-immunological drug repurposing includes strategies to reduce haemodynamic overload, podocyte injury and kidney fibrosis. Recommended strategies to expand drug-repurposing capacity in glomerular disease include enriching drug databases with glomeruli-specific information, enhancing the accessibility of primary clinical trial data, biomarker discovery to improve participant selection into clinical trials and improve surrogate outcomes and initiatives to reduce patent, regulatory and organizational hurdles.

Combination therapy for kidney disease in people with diabetes mellitus

Diabetic kidney disease (DKD), defined as co-existing diabetes and chronic kidney disease in the absence of other clear causes of kidney injury, occurs in approximately 20-40% of patients with diabetes mellitus. As the global prevalence of diabetes has increased, DKD has become highly prevalent and a leading cause of kidney failure, accelerated cardiovascular disease, premature mortality and global health care expenditure. Multiple pathophysiological mechanisms contribute to DKD, and single lifestyle or pharmacological interventions have shown limited efficacy at preserving kidney function. For nearly two decades, renin-angiotensin system inhibitors were the only available kidney-protective drugs. However, several new drug classes, including sodium glucose cotransporter-2 inhibitors, a non-steroidal mineralocorticoid antagonist and a selective endothelin receptor antagonist, have now been demonstrated to improve kidney outcomes in people with type 2 diabetes mellitus. In addition, emerging preclinical and clinical evidence of the kidney-protective effects of glucagon-like-peptide-1 receptor agonists has led to the prospective testing of these agents for DKD. Research and clinical efforts are geared towards using therapies with potentially complementary efficacy in combination to safely halt kidney disease progression. As more kidney-protective drugs become available, the outlook for people living with DKD should improve in the next few decades.

Lessons learned from early-stage clinical trials for diabetic nephropathy

INTRODUCTION

The evolution of treatment for diabetic nephropathy illustrates how basic biochemistry and physiology have led to new agents such as SGLT2 inhibitors and mineralocorticoid blockers. Conversely, clinical studies performed with these agents have suggested new concepts for investigational drug development. We reviewed currently available treatments for diabetic nephropathy and then analyzed early clinical trials of new agents to assess the potential for future treatment modalities.

AREAS COVERED

We searched ClinicalTrials.gov for new agents under study for diabetic nephropathy in the past decade. Once we have identified investigation trials of new agents, we then used search engines and Pubmed.gov to find publications providing insight on these drugs. Current treatments have shown benefit in both cardiac and renal disease. In our review, we found 51 trials and 43 pharmaceuticals in a number of drug classes: mineralocorticoid blockers, anti-inflammatory, anti-fibrosis, nitric oxide stimulatory, and podocyte protection, and endothelin inhibitors.

EXPERT OPINION

It is difficult to predict which early phase treatments will advance to confirmatory clinical trials. Current agents are thought to improve hemodynamic function. However, the coincident benefit of both myocardial function and the glomerulus argues for primary effects at the subcellular level, and we follow the evolution of agents which modify fundamental cellular processes.

Chronic kidney disease in type 1 diabetes: translation of novel type 2 diabetes therapeutics to individuals with type 1 diabetes

Current management of chronic kidney disease (CKD) in type 1 diabetes centres on glycaemic control, renin-angiotensin system inhibition and optimisation of risk factors including blood pressure, lipids and body weight. While these therapeutic approaches have significantly improved outcomes among people with type 1 diabetes and CKD, this population remains at substantial elevated risk for adverse kidney and cardiovascular events, with limited improvements over the last few decades. The significant burden of CKD and CVD in type 1 diabetes populations highlights the need to identify novel therapies with the potential for heart and kidney protection. Over the last decade, sodium-glucose cotransporter-2 inhibitors, glucagon-like peptide 1 receptor agonists and non-steroidal mineralocorticoid receptor antagonists have emerged as potent kidney-protective and/or cardioprotective agents in type 2 diabetes. The consistent, substantial kidney and cardiovascular benefits of these agents has led to their incorporation into professional guidelines as foundational care for type 2 diabetes. Furthermore, introduction of these agents into clinical practice has been accompanied by a shift in the focus of diabetes care from a 'glucose-centric' to a 'cardiorenal risk-centric' approach. In this review, we evaluate the potential translation of novel type 2 diabetes therapeutics to individuals with type 1 diabetes with the lens of preventing the development and progression of CKD.

Expanding options of supportive care in IgA nephropathy

Immunoglobulin A nephropathy (IgAN) is the most common primary glomerulonephritis worldwide, with a potentially serious prognosis. At present, management of IgAN is primarily based on therapeutic lifestyle changes, and excellent blood pressure control and maximized supportive treatment with the combination of inhibition of the renin-angiotensin-aldosterone system with either inhibitors of angiotensin-converting enzyme or angiotensin II receptor blockers and inhibitors of sodium-glucose cotransporter-2, and possibly in the future also with endothelin antagonists. Supportive care currently represents the cornerstone of treatment of IgAN. Targeted-release formulation of budesonide should replace systemic corticosteroids in patients with higher proteinuria and active histological lesions. New treatment options are aimed at immunopathogenesis of IgAN including depletion or modulation of Galactose-deficient-Immunoglobulin A1-producing B cells, plasma cells, and the alternate and/or lectin pathway of complement. The exact place of monoclonal antibodies and complement inhibitors will need to be determined. This article reviews potential supportive therapies currently available for patients with IgAN.

Pathomechanisms of Diabetic Kidney Disease

The worldwide occurrence of diabetic kidney disease (DKD) is swiftly rising, primarily attributed to the growing population of individuals affected by type 2 diabetes. This surge has been transformed into a substantial global concern, placing additional strain on healthcare systems already grappling with significant demands. The pathogenesis of DKD is intricate, originating with hyperglycemia, which triggers various mechanisms and pathways: metabolic, hemodynamic, inflammatory, and fibrotic which ultimately lead to renal damage. Within each pathway, several mediators contribute to the development of renal structural and functional changes. Some of these mediators, such as inflammatory cytokines, reactive oxygen species, and transforming growth factor β are shared among the different pathways, leading to significant overlap and interaction between them. While current treatment options for DKD have shown advancement over previous strategies, their effectiveness remains somewhat constrained as patients still experience residual risk of disease progression. Therefore, a comprehensive grasp of the molecular mechanisms underlying the onset and progression of DKD is imperative for the continued creation of novel and groundbreaking therapies for this condition. In this review, we discuss the current achievements in fundamental research, with a particular emphasis on individual factors and recent developments in DKD treatment.