Tenapanor: A Phosphate Absorption Inhibitor for the Management of Hyperphosphatemia in Patients with Kidney Failure.

Because of increased risks of cardiovascular disease and death, patients with hyperphosphatemia receiving maintenance dialysis are advised to limit phosphorus consumption and are prescribed phosphate binders in an effort to better control serum phosphate concentrations. Because of large pill size, pill burden, and tolerability issues, phosphate binder adherence is relatively poor. On ingestion, phosphate is absorbed from the intestine via transcellular or paracellular transport. Data show that inhibiting sodium-hydrogen exchanger 3 modulates paracellular phosphate absorption (the predominant pathway in humans). Tenapanor is a first-in-class, minimally absorbed, phosphate absorption inhibitor that selectively inhibits sodium-hydrogen exchanger 3, with a mechanism distinct from, and complementary to, that of phosphate binders. In phase 3 and postregistrational studies, tenapanor conferred statistically significant and clinically meaningful reductions in serum phosphate in patients receiving maintenance dialysis with hyperphosphatemia. Here, we review the available preclinical and clinical data on the effects of tenapanor on controlling intestinal phosphate absorption.

Tenapanor improves long-term control of high phosphate concentrations in the blood in patients receiving maintenance dialysis: a plain language summary of the NORMALIZE study.

What is this summary about?This is a summary of an article that was published in the medical journal Kidney360 describing results from the NORMALIZE study. The NORMALIZE study looked at how well tenapanor tablets reduced higher-than-normal levels of phosphate in the blood of persons with kidney disease who are on maintenance dialysis. These persons are unable to keep their blood phosphate levels in a normal range, and high levels of phosphate can contribute to several serious health consequences.Tenapanor is approved as an add-on treatment for high levels of phosphate in the blood of adults with chronic kidney disease who are on maintenance dialysis and whose disease does not respond adequately to treatment with phosphate binders or who are not able to take phosphate binders. In earlier clinical studies, tenapanor was studied alone or studied together with phosphate binders. In a 1-year clinical study called PHREEDOM, researchers learned that when tenapanor was used alone, it lowered blood phosphate levels, and treated patients experienced acceptable safety and tolerability as determined by the doctors running the study. In the NORMALIZE study, adult patients took a 30-mg tenapanor tablet twice a day, either alone or with sevelamer, for up to 18 months after they completed the PHREEDOM study.What were the main conclusions reported by the researchers?The researchers found that one-third of patients taking tenapanor, either alone or with sevelamer, achieved normal blood phosphate levels. This is an improvement from the current standard of care with sevelamer alone to reduce blood phosphate levels. As seen in the earlier studies of tenapanor, the most common adverse event experienced by patients was softer or loose stools. No new safety concerns were reported in the NORMALIZE study.What are the key takeaways?The researchers concluded that tenapanor, used alone or combined with sevelamer, can be used long-term by adult patients receiving maintenance dialysis to reduce the phosphate levels in their blood to within the normal range. Patients who take tenapanor may experience softer or loose stools.This summary was developed by the authors to help adult patients with chronic kidney disease receiving dialysis, and their family members and/or caregivers, better understand the effects of taking tenapanor.[Box: see text]Link to original article here.

Plasmapheresis in ANCA-Associated Vasculitis with Active Kidney Involvement in the United States (2016-2020): A Cross-Sectional Study.

INTRODUCTION: Plasmapheresis is currently recommended when antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) presents with severe kidney and/or lung involvement. This cross-sectional study aimed at describing characteristics of hospitalized patients diagnosed with AAV with severe kidney involvement undergoing plasmapheresis in the US. METHODS: We defined the study population as adults hospitalized for active kidney involvement with a new diagnosis of AAV (by subtype or unspecified). We established the cohort from the 2016-2020 National Inpatient Sample by ICD-10-CM codes. In this cross-sectional study, we described demographic and clinical characteristics, associated inpatient procedures, lengths of stay, hospital costs, and disposition at discharge comparing patients treated and not treated with plasmapheresis. RESULTS: We identified a total of 975 cases of hospitalized AAV with acute kidney involvement in the US treated by plasmapheresis over the 5-year period. Demographic characteristics of patients who received plasmapheresis were similar to those in patients who did not (n=5670). There were no regional differences in the proportion of patients who received plasmapheresis; however, plasmapheresis was deployed more frequently among patients admitted to urban teaching hospitals relative to rural and non-teaching hospitals. Cases treated with plasmapheresis were more likely to have had acute kidney injury (AKI) (96% vs. 90%, p=0.0007), AKI requiring dialysis (52% vs 16%, p<0.001), hypoxia (40% vs. 16%, p<0.0001), and respiratory failure requiring mechanical ventilation (13% vs. 3%, p=0.0003). CONCLUSION: During 2016-2020, plasmapheresis was deployed in approximately 20% of patients being admitted for AAV and acute kidney involvement in the US. As standards of care and practice evolve, the role of plasmapheresis in the management of AAV with acute kidney involvement will require further study.

The Legacy Effect of Intensive versus Standard Blood Pressure Control on the Incidence of Dialysis or Kidney Transplantation.

BACKGROUND: The Systolic Blood Pressure Intervention Trial (SPRINT) showed that intensive lowering of systolic blood pressure (BP) increased the risk of incident chronic kidney disease and episodes of acute kidney injury. Whether intensive treatment changes the risk of kidney failure is unknown. The goal of this study was to estimate the legacy effect of intensive versus standard systolic BP lowering on the longer-term incidence of kidney failure. METHODS: Secondary analysis of a randomized, open-label clinical trial with observational follow-up. Between 2010 and 2013, patients 50 years and older with hypertension and higher cardiovascular risk excluding those with diabetes mellitus, history of stroke, proteinuria >1g / day or polycystic kidney disease were recruited from 102 clinic sites in the United States and Puerto Rico. Participants were randomized to a systolic BP goal of <120 mm Hg (intensive treatment) or <140 mm Hg (standard treatment group). We linked participants with the US Renal Data System to ascertain kidney failure (initiation of dialysis therapy or transplantation) and the US National Death Index to ascertain all-cause mortality through 2020. RESULTS: Based on analysis of 9279 (99.1%) of 9361 randomized participants, 101 cases of kidney failure occurred over a median follow-up of 8.6 years (interquartile range 8.0 to 9.1 years), with the majority occurring in 74 (73.3%) participants with an eGFR<45 ml/min/1.73 m2 at baseline. Intensive treatment did not significantly increase the risk of kidney failure either overall (cause-specific Hazard Ratio (HR) = 1.20, 95% CI: 0.81 - 1.78) or in the subgroup of participants with baseline eGFR<45 ml/min/1.73 m2 (HR = 1.43, 95% CI: 0.89 - 2.30). CONCLUSIONS: Overall, and in patients with eGFR <45 ml/min/1.73 m2, there were higher rates of dialysis or transplantation among SPRINT participants randomized to intensive treatment, but the modest differences observed were not statistically significant.

Selonsertib in Patients with Diabetic Kidney Disease: A Phase 2b Randomized Active Run-In Clinical Trial.

BACKGROUND: Selonsertib is an apoptosis signal-regulating kinase 1 inhibitor that reduces inflammation, fibrosis, and apoptosis. The MOSAIC study evaluated whether selonsertib attenuated kidney function decline in patients with diabetic kidney disease. METHODS: We conducted a phase 2b study in adults with type 2 diabetes and eGFR 20 to <60 ml/min/1.73 m2 with UACR 150 to 5000 mg/g on maximum tolerated dose of ACE inhibitor or ARB. To account for an acute selonsertib-related decrease in eGFRcr, patients entered a 4-week selonsertib run-in period to establish treatment-specific baseline eGFRcr. Patients were randomized 1:1 to selonsertib 18 mg or matching placebo once daily. We followed all participants up until the last randomized participant completed 48 weeks follow-up. The primary efficacy outcome was the difference in eGFRcr slopes from treatment-specific baselines to week 84, evaluated at a prespecified two-sided P = 0.30. We also evaluated kidney clinical events (eGFRcr ≥40% decline from pre-run-in baseline, kidney failure, or death due to kidney disease) and adverse events. RESULTS: In total, 310 patients were randomized (selonsertib n=154, placebo n=156; 68% male, mean age 65 years, mean baseline eGFRcr 35 ml/min/1.73 m2). Mean difference between selonsertib and placebo eGFRcr slopes at week 84 was 1.20 ml/min/1.73 m2/year (95% CI, -0.41 to 2.81; P = 0.14). Kidney clinical events occurred in 17% (26/154) of patients randomized to selonsertib and 12% (19/156) of those randomized to placebo (difference 4.7%; 95% CI, -6.3% to 15.9%). The most common investigator-reported adverse event was acute kidney injury (selonsertib 11.0/100 and placebo 5.9/100 patient-years). CONCLUSIONS: Selonsertib attenuated the decline in eGFRcr over up to 84 weeks; however, it resulted in a numerically higher number of patients reaching a kidney clinical event and a numerically higher rate of investigator-reported acute kidney injury.

Projecting the clinical burden of chronic kidney disease at the patient level (Inside CKD): a microsimulation modelling study.

Background: Chronic kidney disease (CKD) is a global concern that presents significant challenges for disease management. Several factors drive CKD prevalence, including primary risk factors, such as type 2 diabetes and hypertension, and an ageing population. Inside CKD is an international initiative that aims to raise awareness of the substantial burden incurred by CKD. Methods: Using a peer-reviewed microsimulation method, the clinical burden of CKD was estimated from 2022 to 2027. Demographic data from the Americas, Europe, and Asia-Pacific/Middle East were used to generate virtual populations and to project the prevalence of CKD, kidney replacement therapy, associated cardiovascular complications, comorbid conditions, and all-cause mortality in the CKD population over the modelled time frame. Findings: Across the 31 participating countries/regions, the total prevalence of CKD was projected to rise to 436.6 million cases by 2027 (an increase of 5.8% from 2022), with most cases (∼80%) undiagnosed. Inside CKD projected a mean of 8859 cases of heart failure, 10,244 of myocardial infarction, and 7797 of stroke per 100,000 patients with CKD by 2027. Interpretation: The clinical impact of CKD is substantial and likely to increase; the high prevalence of undiagnosed cases and associated complications may benefit from the implementation of health policy interventions that promote screening, earlier diagnosis, and interventions to improve outcomes. Funding: AstraZeneca.

Patient Perspectives on Using Telemedicine During In-Center Hemodialysis: A Qualitative Study.

Rationale & Objective: In the wake of the coronavirus disease 2019 (COVID-19) pandemic, the United States federal government expanded originating telemedicine sites to include outpatient dialysis units. For the first time, nephrology practitioners across the United States could replace face-to-face visits with telemedicine for patients receiving in-center hemodialysis. This study describes patients' perspectives on the use of telemedicine during in-center hemodialysis. Study Design: A qualitative study. Setting & Participants: Thirty-two patients from underserved populations (older, less educated, unemployed, persons of color) receiving in-center hemodialysis who used telemedicine with their nephrologist during the COVID-19 pandemic. Analytical Approach: Telephone semistructured interviews were conducted in English or Spanish. Transcripts were thematically analyzed. Results: We identified 6 themes with subthemes: adapting to telemedicine (gaining familiarity and confidence, overcoming and resolving technical difficulties, and relying on staff for communication); ensuring availability of the physician (enabling an immediate response to urgent medical needs, providing peace of mind, addressing patient needs adequately, and enhanced attention and contact from physicians); safeguarding against infection (limiting COVID-19 exposures and decreasing use); straining communication and physical interactions (loss of personalized touch, limited physical examination, and unable to reapproach physicians about forgotten issues); maintaining privacy (enhancing privacy and projecting voice enables others to hear); and supporting confidence in telemedicine (requiring established rapport with physicians, clinical stabilty of health, and ability to have in-person visits when necessary). Limitations: Interviews were conducted later in the pandemic when some nephrology care providers were using telemedicine infrequently. Conclusions: Patients receiving in-center hemodialysis adapted to telemedicine visits by their nephrologists in the context of the COVID-19 pandemic and observed its benefits. However, further considerations regarding communication, privacy, and physical assessments are necessary. Integrating telemedicine into future in-center hemodialysis care using a hybrid approach could potentially build trust, optimize communication, and augment care.

This study describes patients' perspectives on the use of telemedicine while receiving in-center hemodialysis during the coronavirus disease 2019 (COVID-19) pandemic. Data are derived from semistructured interviews with thirty-two patients from underserved populations (older, less educated, unemployed, persons of color). We identified 6 major themes including adapting to telemedicine, ensuring availability of the physicians, safeguarding against infection, straining communication and physical interactions, maintaining privacy, and supporting confidence in telemedicine. These findings suggest that patients receiving in-center hemodialysis adapted to telemedicine visits by their nephrologists in the context of the COVID-19 pandemic and observed its benefits. However, further considerations regarding communication, privacy, and physical assessments are necessary. Integrating telemedicine into future in-center hemodialysis care using a hybrid approach could potentially build trust, optimize communication, and augment care.

The Medical Costs of Determining Eligibility and Waiting for a Kidney Transplantation.

BACKGROUND: Recent efforts to increase access to kidney transplant (KTx) in the United States include increasing referrals to transplant programs, leading to more pretransplant services. Transplant programs reconcile the costs of these services through the Organ Acquisition Cost Center (OACC). OBJECTIVE: The aim of this study was to determine the costs associated with pretransplant services by applying microeconomic methods to OACC costs reported by transplant hospitals. RESEARCH DESIGN, SUBJECTS, AND MEASURES: For all US adult kidney transplant hospitals from 2013 through 2018 (n=193), we crosslinked the total OACC costs (at the hospital-fiscal year level) to proxy measures of volumes of pretransplant services. We used a multiple-output cost function, regressing total OACC costs against proxy measures for volumes of pretransplant services and adjusting for patient characteristics, to calculate the marginal cost of each pretransplant service. RESULTS: Over 1015 adult hospital-years, median OACC costs attributable to the pretransplant services were $5 million. Marginal costs for the pretransplant services were: initial transplant evaluation, $9k per waitlist addition; waitlist management, $2k per patient-year on the waitlist; deceased donor offer management, $1k per offer; living donor evaluation, procurement and follow-up: $26k per living donor. Longer time on dialysis among patients added to the waitlist was associated with higher OACC costs at the transplant hospital. CONCLUSIONS: To achieve the policy goals of more access to KTx, sufficient funding is needed to support the increase in volume of pretransplant services. Future studies should assess the relative value of each service and explore ways to enhance efficiency.

IL-6 inhibition with clazakizumab in patients receiving maintenance dialysis: a randomized phase 2b trial.

Inflammation mediated by interleukin-6 (IL-6) is strongly associated with cardiovascular risk. Here we evaluated clazakizumab, a monoclonal antibody targeting the IL-6 ligand, in a phase 2b dose-finding study. Adults with cardiovascular disease and/or diabetes receiving maintenance dialysis with high-sensitivity C-reactive protein (hs-CRP) ≥ 2 mg l-1 at baseline were randomized to receive clazakizumab (2.5 mg, 5 mg or 10 mg, n = 32 per dose group) or placebo (n = 31) every 4 weeks. The primary endpoint was the change from baseline in hs-CRP to week 12, expressed as the geometric mean ratio. Clazakizumab treatment signficantly reduced serum hs-CRP concentrations at week 12 by 86%, 90% and 92% relative to placebo in patients randomized to 2.5 mg, 5 mg or 10 mg clazakizumab, respectively (all P < 0.0001), meeting the primary outcome. With regard to secondary endpoints, clazakizumab treatment reduced serum fibrinogen, amyloid A, secretory phospholipase A2, and lipoprotein(a) concentrations, as well as increased mean serum albumin concentrations at 12 weeks, relative to placebo. The proportion of patients who achieved hs-CRP < 2.0 mg l-1 was 79%, 82% and 79% in the 2.5 mg, 5 mg and 10 mg clazakizumab groups, respectively, compared with 0% of placebo-treated patients. With regard to safety, no cases of sustained grade 3 or 4 thrombocytopenia or neutropenia were observed. Serious infections were seen with similar frequency in the placebo, clazakizumab 2.5 mg and clazakizumab 5 mg groups, but were numerically more frequent in the clazakizumab 10 mg group. The results of this trial indicate that in patients receiving maintenance dialysis, clazakizumab reduced inflammatory biomarkers associated with cardiovascular events. ClinicalTrials.gov registration: NCT05485961 .

A Prospective Clinical Study to EvaluAte the AbiliTy of the CloudCath System to Detect Peritonitis During In-Home Peritoneal Dialysis (CATCH).

Introduction: Peritonitis is the leading complication of peritoneal dialysis (PD). Patients are instructed to seek care promptly for signs (cloudy effluent) or symptoms (abdominal pain), and earlier treatment improves outcomes. The CloudCath Peritoneal Dialysis Drain Set Monitoring (CloudCath) system monitors turbidity in dialysis effluent and sends notifications of changes signaling possible peritonitis. Methods: We conducted this single-arm, open-label, multicenter study of CloudCath system use during PD. We deactivated system notifications to participants and investigators, who followed standard-of-care for peritonitis signs and symptoms. Effectiveness endpoints measured time between CloudCath system notifications and peritonitis events using International Society of Peritoneal Dialysis (ISPD) criteria. Results: Two hundred forty-three participants used the CloudCath system for 178.8 patient-years. Of 71 potential peritonitis events, 51 events (0.29 per patient-year) met ISPD white blood cell (WBC) count criteria. The system triggered notifications for 41 of 51 events (80.4%), with a median lead time of 2.6 days (10%-90% range, -1.0 to 15.7; P < 0.0001). Excluding 6 peritonitis events that occurred when the system was not in use, the system triggered notifications for 41 of 45 events (91.1%), with a median lead time of 3.0 days (10%-90% range, -0.5 to 18.8; P < 0.0001). Of the 0.78 notifications per patient-year, the majority were peritonitis events or nonperitonitis events such as exit site and tunnel infections or catheter/cycler issues. Conclusion: The CloudCath system detected peritonitis events during PD several days earlier than the current standard-of-care and has the capacity to send notifications that could expedite peritonitis diagnosis and treatment.

MyPlate Awareness and Engagement and Perceived and Objective Diet Quality in US Adults With Chronic Kidney Disease.

OBJECTIVE: Awareness of federal dietary guidelines has been associated with better perceived and objective diet quality. Little is known about the awareness of federal dietary recommendations among persons with chronic kidney disease (CKD) and the associations between recognition of guidelines, perception of diet quality, and objective quality of the diet in this population. DESIGN AND METHODS: We compared awareness of, and engagement with, MyPlate (a representation of 5 food groups from the US Department of Agriculture) along with perceived and objective diet quality, the latter assessed via Dietary Approaches to Stop Hypertension index scores, among US adults with and without CKD during 2017-2020. RESULTS: Among noninstitutionalized adults in the United States, 8.3% had albuminuria with normal or near-normal kidney function, 4.0% had estimated glomerular filtration rate 45-59 mL/minute/1.73 m2 (CKD stage G3a) and 1.6% had estimated glomerular filtration rate <45 mL/minute/1.73 m2 (CKD stages G3b/G4/G5). MyPlate awareness was lower among persons with CKD compared with those without CKD (19.6% vs. 26.4%, P < .001) and was lower among persons with more advanced CKD stages: 20.8%, 18.2%, and 16.3% in persons with CKD stages G1/G2, G3a, and G3b/G4/G5, respectively (trend P < .001). Among persons aware of MyPlate, a numerically higher proportion with CKD attempted to follow MyPlate recommendations (43.9% vs. 32.3%, P = .10); the proportion was highest among persons with moderate-to-advanced CKD (41.9%, 42.9%, and 56.9% among persons with CKD stages G1/G2, G3a, and G3b/G4/G5, respectively (trend P < .001)). Perceived and objective dietary quality (the latter based on concordance with the Dietary Approaches to Stop Hypertension diet) were slightly higher among persons with CKD relative to those without CKD. CONCLUSIONS: Adults with CKD have lower MyPlate awareness than adults without CKD. Enhancing diet education to persons with CKD could improve diet quality and potentially ameliorate CKD-associated complications.

Effects of Sodium-Glucose Cotransporter 2 Inhibitors on Cause-Specific Cardiovascular Death in Patients with CKD: A Meta-Analysis of CKD Progression Trials.

Clinical Trial registry name and registration number: ClinicalTrials.gov Identifiers: NCT02065791 (CREDENCE), NCT03036150 (DAPA-CKD), NCT03594110 (EMPA-KIDNEY).

Ambient heat exposure and kidney function in patients with chronic kidney disease: a post-hoc analysis of the DAPA-CKD trial.

BACKGROUND: Higher temperatures are associated with higher rates of hospital admissions for nephrolithiasis and acute kidney injury. Occupational heat stress is also a risk factor for kidney dysfunction in resource-poor settings. It is unclear whether ambient heat exposure is associated with loss of kidney function in patients with established chronic kidney disease. We assessed the association between heat index and change in estimated glomerular filtration rate (eGFR) in participants from the DAPA-CKD trial in a post-hoc analysis. METHODS: DAPA-CKD was a randomised controlled trial of oral dapagliflozin 10 mg once daily or placebo that enrolled participants aged 18 years or older, with or without type 2 diabetes, with a urinary albumin-to-creatinine ratio of 200-5000 mg/g, and an eGFR of 25-75 mL/min per 1·73 m2. In this post-hoc analysis, we explored the association between time-varying daily centre-level heat index (ERA5 dataset) and individual-level change in eGFR in trial participants using linear mixed effect models and case-time series. The DAPA-CKD trial is registered with ClinicalTrials.gov, NCT03036150. FINDINGS: Climate and eGFR data were available for 4017 (93·3%) of 4304 participants in 21 countries (mean age: 61·9 years; mean eGFR: 43·3 mL per 1·73 m2; median 28 months follow-up). Across centres, a heat index of more than 30°C occurred on a median of 0·6% of days. In adjusted linear mixed effect models, within each 120-day window, each 30 days' heat index of more than 30°C was associated with a -0·6% (95% CI -0·9% to -0·3%) change in eGFR. Similar estimates were obtained using case-time series. Additional analyses over longer time-windows showed associations consistent with haemodynamic or seasonal variability, or both, but overall estimates corresponded to an additional 3·7 mL per 1·73 m2 (95% CI 0·1 to 7·0) loss of eGFR per year in a patient with an eGFR of 45 mL per 1·73 m2 located in a very hot versus a temperate environment. INTERPRETATION: Higher ambient heat exposure is associated with more rapid eGFR decline in those with established chronic kidney disease. Efforts to mitigate heat exposure should be tested as part of strategies to attenuate chronic kidney disease progression. FUNDING: None.

Effects of RBT-1 on preconditioning response biomarkers in patients undergoing coronary artery bypass graft or heart valve surgery: a multicentre, double-blind, randomised, placebo-controlled phase 2 trial.

Background: RBT-1 is a combination drug of stannic protoporfin (SnPP) and iron sucrose (FeS) that elicits a preconditioning response through activation of antioxidant, anti-inflammatory, and iron-scavenging pathways, as measured by heme oxygenase-1 (HO-1), interleukin-10 (IL-10), and ferritin, respectively. Our primary aim was to determine whether RBT-1 administered before surgery would safely and effectively elicit a preconditioning response in patients undergoing cardiac surgery. Methods: This phase 2, double-blind, randomised, placebo-controlled, parallel-group, adaptive trial, conducted in 19 centres across the USA, Canada, and Australia, enrolled patients scheduled to undergo non-emergent coronary artery bypass graft (CABG) and/or heart valve surgery with cardiopulmonary bypass. Patients were randomised (1:1:1) to receive either a single intravenous infusion of high-dose RBT-1 (90 mg SnPP/240 mg FeS), low-dose RBT-1 (45 mg SnPP/240 mg FeS), or placebo within 24-48 h before surgery. The primary outcome was a preoperative preconditioning response, measured by a composite of plasma HO-1, IL-10, and ferritin. Safety was assessed by adverse events and laboratory parameters. Prespecified adaptive criteria permitted early stopping and enrichment. This trial is registered with ClinicalTrials.gov, NCT04564833. Findings: Between Aug 4, 2021, and Nov 9, 2022, of 135 patients who were enrolled and randomly allocated to a study group (46 high-dose, 45 low-dose, 44 placebo), 132 (98%) were included in the primary analysis (46 high-dose, 42 low-dose, 44 placebo). At interim, the trial proceeded to full enrollment without enrichment. RBT-1 led to a greater preconditioning response than did placebo at high-dose (geometric least squares mean [GLSM] ratio, 3.58; 95% CI, 2.91-4.41; p < 0.0001) and low-dose (GLSM ratio, 2.62; 95% CI, 2.11-3.24; p < 0.0001). RBT-1 was generally well tolerated by patients. The primary drug-related adverse event was dose-dependent photosensitivity, observed in 12 (26%) of 46 patients treated with high-dose RBT-1 and in six (13%) of 45 patients treated with low-dose RBT-1 (safety population). Interpretation: RBT-1 demonstrated a statistically significant cytoprotective preconditioning response and a manageable safety profile. Further research is needed. A phase 3 trial is planned. Funding: Renibus Therapeutics, Inc.

The Use of Telemedicine by US Nephrologists for In-Center Hemodialysis Care During the Pandemic: An Analysis of National Medicare Claims.

Rationale & Objective: Because of coronavirus disease 2019 (COVID-19), the US government issued emergency waivers in March 2020 that removed regulatory barriers around the use of telemedicine. For the first time, nephrologists were reimbursed for telemedicine care delivered during in-center hemodialysis. We examined the use of telemedicine for in-center hemodialysis during the first 16 months of the pandemic. Study Design: We ascertained telemedicine modifiers on nephrologist claims. We used multivariable regression to examine time trends and patient, dialysis facility, and geographic correlates of telemedicine use. We also examined whether the estimated effects of predictors of telemedicine use changed over time. Setting & Participants: US Medicare beneficiaries receiving in-center hemodialysis between March 1, 2020, and June 30, 2021. Exposures: Patient, geographic, and dialysis facility characteristics. Outcomes: The use of telehealth for in-center hemodialysis care. Analytic Approach: Retrospective cohort analysis. Results: Among 267,434 Medicare beneficiaries identified, the reported use of telemedicine peaked at 9% of patient-months in April 2020 and declined to 2% of patient-months by June 2021. Telemedicine use varied geographically and was more common in areas that were remote and socioeconomically disadvantaged. Patients were more likely to receive care by telemedicine in areas with higher incidence of COVID-19, although the predictive value of COVID-19 diminished later in the pandemic. Patients were more likely to receive care using telemedicine if they were at facilities with more staff, and the use of telemedicine varied by facility ownership type. Limitations: Limited reporting of telemedicine on claims could lead to underestimation of its use. Reported telemedicine use was higher in an analysis designed to address this limitation by focusing on patients whose physicians used telemedicine at least once during the pandemic. Conclusions: Some US nephrologists continued to use telemedicine for in-center hemodialysis throughout the pandemic, even as the association between COVID-19 incidence and telemedicine use diminished over time. These findings highlight unique challenges and opportunities to the future use of telemedicine in dialysis care.

Emergency waivers issued during the coronavirus disease 2019 pandemic enabled reimbursement to US nephrologists for telemedicine care delivered during in-center hemodialysis. Using modifiers from Medicare claims, we examined telemedicine use in the first 16 months of the pandemic. Reported telemedicine use peaked early in the pandemic and declined subsequently. Telemedicine use was more common in areas that were remote and socioeconomically disadvantaged and at facilities with more staff. Telemedicine use also varied by facility ownership type. Some nephrologists continued to use telemedicine for in-center hemodialysis throughout the pandemic, even as the association between coronavirus disease 2019 incidence and telemedicine use diminished over time. These findings highlight unique challenges and opportunities to the future use of telemedicine in dialysis care.

Safety and Tolerability of the APOL1 Inhibitor, Inaxaplin, following Single- and Multiple-Ascending Doses in Healthy Adults.

Introduction: Toxic gain-of-function Apolipoprotein L1 (APOL1) variants contribute to the development of proteinuric nephropathies collectively referred to as APOL1-mediated kidney disease (AMKD). Despite standard-of-care treatments, patients with AMKD experience accelerated progression to end-stage kidney disease. The identification of two APOL1 variants as the genetic cause of AMKD inspired development of inaxaplin, an inhibitor of APOL1 channel activity that reduces proteinuria in patients with AMKD. Methods: We conducted two phase 1 studies evaluating the safety, tolerability, and pharmacokinetics of single-ascending doses (SAD) and multiple-ascending doses (MAD) of inaxaplin in healthy participants. In the SAD cohorts, participants were randomized to receive inaxaplin as a single dose (range, 7.5 mg to 165 mg) or placebo. In the MAD cohorts, participants were randomized to receive multiple doses of inaxaplin (range, 15 to 120 mg daily) or placebo for 14 days. We assessed safety and tolerability based on adverse events (AEs), clinical laboratory values, electrocardiograms (ECGs), and vital signs. Results: A total of 178 participants were randomized in the SAD/MAD cohorts of both studies (mean age: 36.7 years; 94.9% male). The proportion of participants with any AEs was similar in the inaxaplin (24.6%) and placebo (22.7%) groups. All AEs were mild or moderate in severity; there were no serious AEs. Headache was the most common AE: 10.4% and 2.3% in the inaxaplin and placebo groups, respectively. There were no drug-related treatment discontinuations and no clinically relevant trends in laboratory values, ECGs, or vital signs. Discussion/Conclusion: Inaxaplin is safe and well tolerated at single doses up to 165 mg and multiple doses up to 120 mg daily for 14 days. These results are consistent with the favorable safety profile of inaxaplin in a completed phase 2a proof-of-concept study. Together, these findings support continued evaluation of inaxaplin in an ongoing phase 2/3 pivotal trial as a potential precision medicine for patients with AMKD.