Dapagliflozin and Anemia in Patients with Chronic Kidney Disease

Is There a Role for SGLT2 Inhibitors in Patients with End-Stage Kidney Disease?

PURPOSE OF REVIEW

Chronic kidney disease and end-stage kidney disease (ESKD) are well-established risk factors for cardiovascular disease (CVD), the leading cause of mortality in the dialysis population. Conventional therapies, such as statins, blood pressure control, and renin-angiotensin-aldosterone system blockade, have inadequately addressed this cardiovascular risk, highlighting the unmet need for effective treatment strategies. Sodium-glucose transporter 2 (SGLT2) inhibitors have demonstrated significant renal and cardiovascular benefits among patients with type 2 diabetes, heart failure, or CKD at risk of progression. Unfortunately, efficacy data in dialysis patients is lacking as ESKD was an exclusion criterion for all major clinical trials of SGLT2 inhibitors. This review explores the potential of SGLT2 inhibitors in improving cardiovascular outcomes among patients with ESKD, focusing on their direct cardiac effects.

RECENT FINDINGS

Recent clinical and preclinical studies have shown promising data for the application of SGLT2 inhibitors to the dialysis population. SGLT2 inhibitors may provide cardiovascular benefits to dialysis patients, not only indirectly by preserving the remaining kidney function and improving anemia but also directly by lowering intracellular sodium and calcium levels, reducing inflammation, regulating autophagy, and alleviating oxidative stress and endoplasmic reticulum stress within cardiomyocytes and endothelial cells. This review examines the current clinical evidence and experimental data supporting the use of SGLT2 inhibitors, discusses its potential safety concerns, and outlines ongoing clinical trials in the dialysis population. Further research is needed to evaluate the safety and effectiveness of SGLT2 inhibitor use among patients with ESKD.

SGLT2 inhibitors across the spectrum of chronic kidney disease: a narrative review

Chronic kidney disease (CKD) is a growing public health concern, affecting at least 1 in 7 adults in the United States, and accounting for a large proportion of healthcare spending. The risk of mortality rises steeply with declining kidney function, mostly due to cardiovascular-related deaths. Since CKD is asymptomatic in the early stages, diagnosis is sometimes delayed. However, early diagnosis is important for timely initiation of interventions to reduce disease progression, and to avoid the need for hospitalizations, dialysis, or kidney transplantation. This review focuses on the impact of sodium glucose transporter 2 inhibitors (SGLT2i) on CKD based on mechanistic and clinical trial evidence. These agents affect the kidneys through changes in sodium transport and metabolic factors that interfere with the primary pathological mechanisms shared by most kidney diseases. Following clinical trials of SGLT2i in patients with type 2 diabetes which demonstrated reductions in the risk of major adverse CV events, death, and hospitalizations for heart failure (HHF), and in patients with heart failure (HF) with and without diabetes which showed reductions in death and HHF, recent trials in patients with CKD have provided overwhelming support for the use of SGLT2i as foundational therapy across a broad spectrum of patients with CKD, regardless of diabetes status, primary kidney disease (except polycystic kidney disease), or kidney function. While clinical trials in CKD generally recruit patients with a high risk of events, patients at lower risk could also benefit from SGLT2i in terms of reduction of CKD progression, HF, and death, as well as other beneficial effects including reductions in blood sugar, body weight, and blood pressure.

Design and Rationale of the Phase 2 Baricitinib Study in Apolipoprotein L1-Mediated Kidney Disease (JUSTICE)

Introduction

Individuals of recent West African ancestry develop focal segmental glomerulosclerosis (FSGS) and hypertension-attributed end-stage kidney disease (HTN-ESKD) at 4 times the rate of White Americans. Two protein-coding variants of the Apolipoprotein L1 (APOL1) gene, G1 and G2, explain 50% to 70% of the excess risk of HTN-ESKD and FSGS among this group. Increased expression of G1 and G2 in the kidney, mediated by Janus kinase/signal transducer and activator of transcription (JAK-STAT) signaling, drive pathogenesis of these kidney diseases. Baricitinib is an orally active inhibitor of JAK1/2 that blocks APOL1 synthesis. The Janus kinase-STAT Inhibition to Reduce APOL1-Associated Kidney Disease (JUSTICE) trial is evaluating the antiproteinuric efficacy and safety of baricitinib in patients with APOL1-associated FSGS and HTN-attributed chronic kidney disease (HTN-CKD).

Methods

JUSTICE is a single-center, randomized, double-blind, placebo-controlled, pilot phase 2 trial of baricitinib in patients with proteinuria, APOL1-associated FSGS or APOL1-associated HTN-CKD without diabetes. A total of 75 African American patients with APOL1-associated CKD, including 25 with FSGS and 50 with HTN-CKD, aged 18 to 70 years will be randomized 2:1 to daily treatment with baricitinib or placebo, respectively.

Results

The primary efficacy end point will be percent change in urine albumin-to-creatinine ratio (UACR) from baseline to end of month 6. The primary safety end point will be incidence of clinically significant decreases in hemoglobin of ≥ 1g/dl.

Conclusion

The phase 2 JUSTICE study will characterize the antiproteinuric efficacy and safety of JAK1/2 inhibition with baricitinib in patients with APOL1-associated FSGS and APOL1-associated HTN-CKD.

Inhibition of sodium-glucose cotransporter-2 improves anaemia in mice and humans with sickle cell disease, and reduces infarct size in a murine stroke model

Sodium-glucose cotransporter-2 (SGLT-2) is expressed in the kidney and may contribute to anaemia and cardiovascular diseases. The effect of SGLT-2 inhibition on anaemia and vascular endpoints in sickle cell disease (SCD) is unknown. A murine model of SCD was studied to determine the effects of the SGLT-2 inhibitor, empagliflozin, on anaemia and stroke size. The University of Michigan's Precision Health Database was used to evaluate the effect of SGLT-2 inhibitors on anaemia in humans with SCD. SCD mice treated with daily empagliflozin for 8 weeks demonstrated increases in haemoglobin, haematocrit, erythrocyte counts, reticulocyte percentage and erythropoietin compared to vehicle-treated mice. Following photochemical-induced thrombosis of the middle cerebral artery, mice treated with empagliflozin demonstrated reduced stroke size compared to vehicle treated mice. In the electronic health records analysis, haemoglobin, haematocrit and erythrocyte counts increased in human SCD subjects treated with an SGLT-2 inhibitor. SGLT-2 inhibitor treatment of humans and mice with SCD is associated with improvement in anaemic parameters. Empagliflozin treatment is also associated with reduced stroke size in SCD mice suggesting SGLT-2 inhibitor treatment may be beneficial with regard to both anaemia and vascular complications in SCD patients.

Impact of Empagliflozin on the Outcomes of β-Thalassemia Major in Patients With Type 2 Diabetes Mellitus: The THALEMPA Observational Study

OBJECTIVE

Beta-thalassemia major (β-TM) is a genetic disorder characterized by ineffective erythropoiesis and chronic hemolytic anemia, necessitating lifelong blood transfusions and leading to severe complications. This study, termed THALEMPA by the authors, investigated the effect of empagliflozin (EMPA) on β-TM outcomes in patients with type 2 diabetes mellitus (T2DM), focusing on disease severity and associated complications of iron overload and hyperuricemia.

METHODOLOGY

This study conducted a single-center prospective observational investigation involving adults diagnosed with β-TM and T2DM. A total of 20 carefully selected patients were stratified into two groups based on their medical condition: the EMPA group, receiving 10 mg of empagliflozin, and a control group, receiving standard care. This focused cohort size was chosen to ensure a detailed, in-depth analysis of the treatment effects within this specific patient population. Over three months, both groups were closely monitored for β-TM outcomes. The study assessed β-TM severity parameters such as hemoglobin levels, blood transfusion frequency, aspartate aminotransferase (AST), alanine aminotransferase (ALT), left ventricular ejection fraction percentage, and spleen size. Additionally, β-TM complications were evaluated through serum ferritin and uric acid levels.

RESULTS

Our analysis revealed that EMPA increased hemoglobin levels by up to 0.56 g/dL compared to baseline (P < 0.05). Liver enzyme levels significantly improved with EMPA by the third month. AST and ALT decreased by 36.22% and 33.36%, respectively, from baseline levels (P < 0.05), highlighting EMPA's potential benefits for β-TM severity. Serum ferritin and uric acid levels decreased by 27.93% and 21.29%, respectively, over three months on EMPA (P < 0.05). However, other parameters did not show significant changes post-EMPA.

CONCLUSIONS

This study demonstrates the significant impact of EMPA treatment over three months on β-TM patients with T2DM, evidenced by notable improvements in hemoglobin levels and reductions in liver enzymes, as well as in complications related to iron overload and hyperuricemia. Future research should confirm these benefits over longer durations and assess broader patient outcomes such as quality of life.

Effects of Sodium-Glucose Cotransporter 2 Inhibitors in Diabetic and Non-Diabetic Patients with Advanced Chronic Kidney Disease in Peritoneal Dialysis on Residual Kidney Function: In Real-World Data

Background and Objectives: Peritoneal dialysis (PD) is a renal replacement therapy modality in which the dialysis dose can be individually adapted according to the patients' residual kidney function (RKF). RKF is a crucial factor for technique and patient survival. Pharmacological strategies aimed at slowing the loss of RKF in patients on PD are limited. Therefore, we aimed to assess the potential effects and safety of sodium-glucose cotransporter 2 (SGLT-2) inhibitors on the preservation of RKF in patients with and without type 2 diabetes mellitus (T2DM) on PD during an average follow-up of 6 months. Materials and Methods: In this retrospective observational, single-center study on real-world data, we included patients from the Peritoneal Dialysis Unit of the Hospital General Universitario de Ciudad Real, who started treatment with SGLT-2 inhibitors during the period from December 2022 to December 2023. Data on analytical and clinical parameters, RKF, and peritoneal membrane transport function were retrospectively collected at months 0, 3, and 6. Results: Out of 31 patients in our unit, 16 prevalent patients initiated treatment with SGLT-2 inhibitors (13 empagliflozin and 3 dapagliflozin). A total of 62.5% were male and the mean age was 67.3 years. The baseline peritoneal ultrafiltration was higher in the non-diabetic patient (NDMP) group than in the diabetic patient (DMP) group. However, the residual diuresis volume, 24 h residual renal clearance rate of urea in urine, and 24 h proteinuria were higher in the DMP group than in the NDMP group. At the sixth month, patients in both groups preserved RKF and diuresis, with a trend towards a non-significant reduction in proteinuria and blood pressure. Only two patients of the DMP group presented adverse effects. Conclusions: The use of SGLT-2 inhibitors in our sample of patients with and without T2DM on PD appears to be safe and effective to preserve RKF.

Erythropoiesis and estimated fluid volume regulation following initiation of ipragliflozin treatment in patients with type 2 diabetes mellitus and chronic kidney disease: A post-hoc analysis of the PROCEED trial

AIMS

To analyse the changes in erythropoietic and estimated fluid volume parameters after the initiation of ipragliflozin, a sodium-glucose co-transporter 2 inhibitor, in patients with type 2 diabetes mellitus (T2DM) and chronic kidney disease (CKD).

METHODS

This was a post-hoc analysis of the PROCEED trial, which evaluated the effect of 24-week ipragliflozin treatment on endothelial dysfunction in patients with T2DM and CKD. We evaluated the changes in erythropoietic and estimated fluid volume parameters from baseline to 24 weeks post-treatment in 53 patients who received ipragliflozin (ipragliflozin group) and 55 patients with T2DM and CKD without sodium-glucose co-transporter 2 inhibitors (control group), a full analysis set of the PROCEED trial.

RESULTS

The increases in haemoglobin [estimated group difference, 0.5 g/dl; 95% confidence interval (CI), 0.3-0.8; p < .001], haematocrit (estimated group difference, 2.2%; 95% CI, 1.3-3.1; p < .001) and erythropoietin (estimated log-transformed group difference, 0.1; 95% CI, 0.01-0.3; p = .036) were significantly greater in the ipragliflozin group than those in the control group. Ipragliflozin treatment was significantly associated with an increase in erythropoietin, independent of the corresponding change in haemoglobin (β = 0.253, p < .001) or haematocrit (β = 0.278, p < .001). Reductions in estimated plasma volume (estimated group difference, -7.94%; 95% CI, -11.6 to -4.26%; p < .001) and estimated extracellular volume (estimated group difference, -181.6 ml; 95% CI, -275.7 to -87.48 ml; p < .001) were significantly greater in the ipragliflozin group than those in the control group.

CONCLUSIONS

Erythropoiesis was enhanced and estimated fluid volumes were reduced by ipragliflozin in patients with T2DM and CKD.

CLINICAL TRIAL

PROCEED trial (registration number: jRCTs071190054).

Drugs in Development to Treat IgA Nephropathy

IgA nephropathy is a common glomerulonephritis consequent to the autoimmune response to aberrant glycosylated immunoglobulin (Ig) A antibodies. Although it has historically been considered a benign disease, it has since become clear that a substantial percentage of patients reach end-stage kidney failure over the years. Several therapeutic attempts have been proposed, with systemic steroids being the most prevalent, albeit burdened by possible serious adverse events. Thanks to the more in-depth knowledge of the pathogenesis of IgA nephropathy, new treatment targets have been identified and new drugs developed. In this narrative review, we summarise the molecules under clinical development for the treatment of IgA nephropathy. As a search strategy, we used PubMed, Google, ClinicalTrials.gov and abstracts from recent international congresses. TRF budesonide and sparsentan are the two molecules at a more advanced stage, just entering the market. Other promising agents are undergoing phase III clinical development. These include anti-APRIL and anti-BLyS/BAFF antibodies and some complement inhibitors. Other new possible strategies include spleen tyrosine kinase inhibitors, anti-CD40 ligands and anti-CD38 antibodies. In an era increasingly characterised by 'personalised medicine' and 'precision therapy' approaches and considering that the potential therapeutic armamentarium for IgA nephropathy will be very broad in the near future, the identification of biomarkers capable of helping the nephrologist to select the right drug for the right patient should be the focus of future studies.

Use of SGLT2 Inhibitors vs GLP-1 RAs and Anemia in Patients With Diabetes and CKD

Importance

Sodium-glucose cotransporter 2 (SGLT2) inhibitors are associated with lower anemia risk, based on findings from post hoc analyses of the CREDENCE and DAPA-CKD trials; however, the effectiveness of SGLT2 inhibitors in a more generalizable type 2 diabetes (T2D) and chronic kidney disease (CKD) population, with active comparisons pertinent to current practice, is unknown.

Objective

To evaluate and compare anemia incidence between SGLT2 inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1 RAs) among patients with T2D and CKD stages 1 to 3.

Design, Setting, and Participants

This retrospective cohort study used target trial emulation of an expanded CREDENCE and DAPA-CKD study framework. The study was conducted among adults with T2D and CKD initiating SGLT2 inhibitors or GLP-1 RAs between January 1, 2016, and December 31, 2021, with follow-up until December 31, 2022. The study was conducted at the Chang Gung Medical Foundation, the largest multi-institutional hospital system in Taiwan.

Exposures

Initiation of SGLT2 inhibitors or GLP-1 RAs.

Main Outcomes and Measures

The primary outcome was a composite of anemia outcomes, including anemia event occurrence (hemoglobin level <12-13 g/dL or International Statistical Classification of Diseases, Tenth Revision, Clinical Modification diagnosis codes) or anemia treatment initiation. Changes in hematological parameters, including hemoglobin level, hematocrit level, and red blood cell count, were evaluated during the follow-up period for as long as 3 years.

Results

The cohort included a total of 13 799 patients with T2D and CKD, initiating SGLT2 inhibitors (12 331 patients; mean [SD] age, 62.4 [12.3] years; 7548 [61.2%] male) or GLP-1 RAs (1468 patients; mean [SD] age, 61.5 [13.3] years; 900 [61.3%] male). After the median follow-up period of 2.5 years, patients receiving SGLT2 inhibitors had lower incidence of composite anemia outcomes (hazard ratio [HR], 0.81; 95% CI, 0.73-0.90) compared with those receiving GLP-1 RAs. SGLT2 inhibitors were associated with a lower incidence of anemia events (HR, 0.79; 95% CI, 0.71-0.87) but not with a lower rate of anemia treatment initiation (HR, 0.99; 95% CI, 0.83-1.19). Changes in hematological parameters for SGLT2 inhibitors and GLP-1 RAs throughout the 3-year follow-up period supported the primary analyses.

Conclusions and Relevance

In this multi-institutional cohort study with target trial emulation, SGLT2 inhibitors were associated with a decreased risk of composite anemia outcomes, especially anemia event occurrences. SGLT2 inhibitors may be considered as an adjunct therapy to reduce anemia incidence in patients with T2D and CKD.

Effect of SGLT2 inhibitors on anemia and their possible clinical implications

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have demonstrated cardiovascular and renal benefits in patients with type 2 diabetes mellitus, heart failure, or chronic kidney disease. Since the first studies with these drugs, an initial increase in hemoglobin/hematocrit levels was observed, which was attributed to an increase in hemoconcentration associated with its diuretic effect, although it was early appearent that these drugs increased erythropoietin levels and erythropoiesis, and improved iron metabolism. Mediation studies found that the increase in hemoglobin was strongly associated with the cardiorenal benefits of these drugs. In this review, we discuss the mechanisms for improving erythropoiesis and the implication of the increase in hemoglobin on the cardiorenal prognostic benefit of these drugs.

Effects of dapagliflozin and dapagliflozin-saxagliptin on erythropoiesis, iron and inflammation markers in patients with type 2 diabetes and chronic kidney disease: data from the DELIGHT trial

BACKGROUND

This post-hoc analysis of the DELIGHT trial assessed effects of the SGLT2 inhibitor dapagliflozin on iron metabolism and markers of inflammation.

METHODS

Patients with type 2 diabetes and albuminuria were randomized to dapagliflozin, dapagliflozin and saxagliptin, or placebo. We measured hemoglobin, iron markers (serum iron, transferrin saturation, and ferritin), plasma erythropoietin, and inflammatory markers (urinary MCP-1 and urinary/serum IL-6) at baseline and week 24.

RESULTS

360/461 (78.1%) participants had available biosamples. Dapagliflozin and dapagliflozin-saxagliptin, compared to placebo, increased hemoglobin by 5.7 g/L (95%CI 4.0, 7.3; p < 0.001) and 4.4 g/L (2.7, 6.0; p < 0.001) and reduced ferritin by 18.6% (8.7, 27.5; p < 0.001) and 18.4% (8.7, 27.1; p < 0.001), respectively. Dapagliflozin reduced urinary MCP-1/Cr by 29.0% (14.6, 41.0; p < 0.001) and urinary IL-6/Cr by 26.6% (9.1, 40.7; p = 0.005) with no changes in other markers.

CONCLUSIONS

Dapagliflozin increased hemoglobin and reduced ferritin and urinary markers of inflammation, suggesting potentially important effects on iron metabolism and inflammation.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02547935.

Dapafliglozin and Correction of Anemia in Patients with CKD

Anemia of chronic kidney disease (CKD) develops as kidney function declines. Reduced erythropoietin production, iron deficiency, and inflammation are the most important causes of CKD anemia. Anemia in the healthy population is defined by World Health Organization (WHO) criteria: for women, a hemoglobin (Hb) of less than 12 g/dl, and for men, an Hb of less than 13 g/dl. However, for practical purposes, severe anemia in patients with CKD requiring treatment is defined by a threshold Hb of less than 10 g/dl.