Retraction notice to "Pooled Analysis of Roxadustat for Anemia in Patients With Kidney Failure Incident to Dialysis." Kidney Int Rep. 2021;6:613-623.

[This retracts the article DOI: 10.1016/j.ekir.2020.12.018.].

Efficacy and Cardiovascular Safety of Roxadustat for Treatment of Anemia in Patients with Non-Dialysis-Dependent CKD: Pooled Results of Three Randomized Clinical Trials.

BACKGROUND AND OBJECTIVES: We evaluated the efficacy and cardiovascular safety of roxadustat versus placebo by analyzing data pooled from three phase 3 studies of roxadustat in patients with non-dialysis-dependent CKD and CKD-related anemia. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: In the three phase 3, double-blind studies of roxadustat versus placebo evaluating the treatment of CKD-related anemia in patients not requiring dialysis, the primary efficacy end point was mean change from baseline in hemoglobin averaged over weeks 28-52, regardless of rescue therapy. The primary cardiovascular safety end point was a composite measure of major adverse cardiovascular events (MACE; all-cause mortality, myocardial infarction, stroke). MACE plus (MACE+; MACE plus unstable angina and heart failure requiring hospitalization) and all-cause mortality were key secondary safety end points. These safety end points were adjudicated. RESULTS: A total of 4277 patients with non-dialysis-dependent CKD were randomized (roxadustat, n=2391; placebo, n=1886). Baseline characteristics were comparable between groups; the mean (SD) hemoglobin was 9.1 (0.7) g/dl and mean eGFR was 20 (12) ml/min per 1.73 m2. Patients treated with roxadustat versus those treated with placebo showed a mean change from baseline in hemoglobin averaged over weeks 28-52, regardless of rescue therapy, of 1.9 versus 0.2 g/dl, a treatment difference of 1.7 (95% confidence interval [95% CI], 1.7 to 1.8). Roxadustat reduced the need for red blood cell transfusion in the first 52 weeks versus placebo (6.1 versus 20.4 per 100 patient-exposure years, respectively; hazard ratio [HR], 0.26; 95% CI, 0.21 to 0.32). There were no increased risks of MACE (HR, 1.10; 95% CI, 0.96 to 1.27), MACE+ (HR, 1.07; 95% CI, 0.94 to 1.21), all-cause mortality (HR, 1.08; 95% CI, 0.93 to 1.26), or individual MACE+ components in patients treated with roxadustat versus those treated with placebo. CONCLUSIONS: Roxadustat was more effective than placebo at increasing hemoglobin in patients with non-dialysis-dependent CKD and anemia, while decreasing transfusion rate and being noninferior to placebo with respect to risk of MACE. CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER: A Study of FG-4592 for the Treatment of Anemia in Chronic Kidney Disease Patients Not Receiving Dialysis, NCT01750190; Roxadustat in the Treatment of Anemia in Chronic Kidney Disease Patients Not Requiring Dialysis (ALPS), NCT01887600; Safety and Efficacy Study of Roxadustat to Treat Anemia in Patients With Chronic Kidney Disease (CKD), Not on Dialysis, NCT02174627.

Pooled Analysis of Roxadustat for Anemia in Patients With Kidney Failure Incident to Dialysis.

INTRODUCTION: Erythropoiesis-stimulating agents are associated with increased cardiovascular risk when higher doses are used toward higher hematocrit targets. Patients new to dialysis are at higher risk for morbidity and mortality. Systematic evaluation of this population was predefined in the roxadustat clinical development program. Roxadustat is a hypoxia-inducible prolyl hydroxylase inhibitor. METHODS: Data were pooled from 3 phase 3, randomized, open-label, active-controlled trials. Eligible adults had kidney failure and initiated dialysis for 2 weeks to ≤ 4 months prior to randomization to roxadustat or epoetin alfa. Efficacy was assessed as mean change in hemoglobin from baseline averaged over weeks 28 to 52, regardless of rescue therapy. Key cardiovascular safety endpoints were major adverse cardiovascular events (MACE; all-cause mortality [ACM], myocardial infarction, and stroke), and MACE+ (MACE plus unstable angina or congestive heart failure requiring hospitalization), and ACM. RESULTS: This study included 1530 patients with kidney failure incident to dialysis. Mean (SD) changes in hemoglobin from baseline averaged over weeks 28 to 52, regardless of rescue therapy, were 2.12 (1.45) versus 1.91 (1.42) g/dl in the roxadustat and epoetin alfa groups (least-squares mean difference: 0.22; 95% CI, 0.05 to 0.40; P = 0.0130). Risks of MACE and MACE+ were lower in the roxadustat group (hazard ratio [HR], 0.70; 95% CI, 0.51 to 0.96) than the epoetin alfa group (HR, 0.66; 95% CI, 0.50 to 0.89); the HR for ACM was 0.76 (95% CI, 0.52 to 1.11). CONCLUSION: Roxadustat was at least as efficacious as epoetin alfa. Roxadustat had a lower risk of MACE/MACE+ in patients new to dialysis.

Roxadustat for anemia in patients with end-stage renal disease incident to dialysis.

BACKGROUND: We evaluated the efficacy and safety of roxadustat versus epoetin alfa for the treatment of chronic kidney disease-related anemia in patients new to dialysis. METHODS: HIMALAYAS was a Phase 3, open-label, epoetin alfa-controlled trial. Eligible adults were incident to hemodialysis/peritoneal dialysis for 2 weeks to ≤4 months prior to randomization and had mean hemoglobin (Hb) ≤10.0 g/dL. Primary endpoints were mean Hb (g/dL) change from baseline averaged over Weeks 28-52 regardless of rescue therapy [non-inferiority criterion: lower limit of 95% confidence interval (CI) for treatment difference >-0.75] and percentage of patients achieving an Hb response between Weeks 1 and 24 censored for rescue therapy (non-inferiority margin for between-group difference -15%). Adverse events were monitored. RESULTS: The intent-to-treat population included patients randomized to roxadustat (n = 522) or epoetin alfa (n = 521). Mean (standard deviation) Hb changes from baseline averaged over Weeks 28-52 were 2.57 (1.27) and 2.36 (1.21) in the roxadustat and epoetin alfa groups. Roxadustat was non-inferior [least squares mean difference: 0.18 (95% CI 0.08, 0.29)] to epoetin alfa. Percentages of patients with an Hb response were 88.2% and 84.4% in the roxadustat and epoetin alfa groups, respectively. Roxadustat was non-inferior to epoetin alfa [treatment-group difference 3.5% (95% CI -0.7%, 7.7%)]. Adverse event rates were comparable between treatment groups. CONCLUSIONS: Roxadustat was efficacious for correcting and maintaining Hb levels compared with epoetin alfa. Roxadustat had an acceptable safety profile.

Oral Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitor Roxadustat (FG-4592) for Treatment of Anemia in Chronic Kidney Disease: A Placebo-Controlled Study of Pharmacokinetic and Pharmacodynamic Profiles in Hemodialysis Patients.

Roxadustat (FG-4592), an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that stimulates erythropoiesis, was evaluated in a phase 1b study in patients with end-stage renal disease with anemia on hemodialysis. Seventeen patients, on epoetin-alfa maintenance therapy with stable hemoglobin levels ≥10 g/dL, had epoetin-alfa discontinued on day 3 and were enrolled in this double-blind placebo-controlled study. Two cohorts were randomized 3:1 (roxadustat: placebo). Patients received single doses of roxadustat (1 or 2 mg/kg) or placebo 1 hour after hemodialysis on day 1 and 2 hours before dialysis on day 8. Maximum plasma concentration and area under the plasma concentration-time curve for patients receiving roxadustat were slightly more than dose proportional and elimination half-life ranged from 14.7 to 19.4 hours. Roxadustat was highly protein bound (99%) in plasma, and dialysis contributed a small fraction of the total clearance: only 4.56% and 3.04% of roxadustat recovered from the 1 and 2 mg/kg dose groups, respectively. Roxadustat induced transient elevations of endogenous erythropoietin that peaked between 7 and 14 hours after dosing and returned to baseline by 48 hours after dosing. Peak median endogenous erythropoietin levels were 96 mIU/mL and 268 mIU/mL for the 1- and 2-mg/kg doses, respectively, within physiologic range of endogenous erythropoietin responses to hypoxia at high altitude or after blood loss. No serious adverse events were reported, and there were no treatment- or dose-related trends in adverse event incidence.

Nonclinical Characterization of the Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitor Roxadustat, a Novel Treatment of Anemia of Chronic Kidney Disease.

Anemia of chronic kidney disease (CKD) is a multifactorial disorder caused by impaired erythropoietin (EPO) production and altered iron homeostasis associated with inflammation. Hypoxia-inducible factor (HIF) is a transcription factor that stimulates erythropoiesis via a coordinated response involving increased EPO production and enhanced iron availability for Hb synthesis. HIF degradation is regulated by HIF-prolyl hydroxylase (HIF-PH) enzymes. We hypothesized that roxadustat, an orally available small-molecule inhibitor of HIF-PH, would increase EPO production and promote erythropoiesis in animal models of anemia. In cells, roxadustat increased both HIF-1α and HIF-2α proteins, leading to an increase in EPO production, even in the presence of EPO-suppressing inflammatory cytokines. Roxadustat administered intermittently to healthy rats and cynomolgus monkeys increased circulating EPO levels, reticulocytes, blood Hb, and hematocrit in a dose-dependent manner. Roxadustat corrected anemia in a rat model of CKD after five-sixth nephrectomy and in a rat model of anemia of inflammation with impaired iron metabolism induced by peptidoglycan-polysaccharide (PG-PS). In the PG-PS model, roxadustat significantly decreased hepatic expression of hepcidin, a hormone responsible for iron sequestration and functional iron deficiency, and increased expression of two genes involved in duodenal iron absorption: divalent metal transporter 1 and duodenal cytochrome b. In conclusion, by activating the HIF pathway, roxadustat increased EPO production, elevated Hb, corrected anemia, and improved iron homeostasis. The coordinated erythropoietic response stimulated by roxadustat, involving both EPO production and mobilization of iron stores, makes this compound a promising treatment of anemia of CKD and anemia associated with functional iron deficiency. SIGNIFICANCE STATEMENT: Roxadustat is a novel orally available small-molecule inhibitor of HIF prolyl hydroxylase enzymes that reversibly stabilizes HIF-α, thus activating transcription of HIF-dependent genes, including EPO and regulators of iron homeostasis. Activation of the HIF pathway by roxadustat induces erythropoiesis in healthy rats and monkeys and corrects experimentally induced anemia in rats. The coordinated erythropoietic response that increases EPO production and mobilizes iron stores makes roxadustat a promising treatment for anemia of chronic kidney disease and anemia associated with functional iron deficiency.

Phase 2 studies of oral hypoxia-inducible factor prolyl hydroxylase inhibitor FG-4592 for treatment of anemia in China.

BACKGROUND: FG-4592 (roxadustat) is an oral hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor (HIF-PHI) promoting coordinated erythropoiesis through the transcription factor HIF. Two Phase 2 studies were conducted in China to explore the safety and efficacy of FG-4592 (USAN name: roxadustat, CDAN name: ), a HIF-PHI, in patients with anemia of chronic kidney disease (CKD), both patients who were dialysis-dependent (DD) and patients who were not dialysis-dependent (NDD). METHODS: In the NDD study, 91 participants were randomized to low (1.1-1.75 mg/kg) or high (1.50-2.25 mg/kg) FG-4592 starting doses or to placebo. In the DD study, 87 were enrolled to low (1.1-1.8 mg/kg), medium (1.5-2.3 mg/kg) and high (1.7-2.3 mg/kg) starting FG-4592 doses or to continuation of epoetin alfa. In both studies, only oral iron supplementation was allowed. RESULTS: In the NDD study, hemoglobin (Hb) increase ≥1 g/dL from baseline was achieved in 80.0% of subjects in the low-dose cohort and 87.1% in the high-dose cohort, versus 23.3% in the placebo arm (P < 0.0001, both). In the DD study, 59.1%, 88.9% (P = 0.008) and 100% (P = 0.0003) of the low-, medium- and high-dose subjects maintained their Hb levels after 5- and 6-weeks versus 50% of the epoetin alfa-treated subjects. In both studies, significant reductions in cholesterol were noted in FG-4592-treated subjects, with stability or increases in serum iron, total iron-binding capacity (TIBC) and transferrin (without intravenous iron administration). In the NDD study, hepcidin levels were significantly reduced across all FG-4592-treated arms as compared with no change in the placebo arm. In the DD study, hepcidin levels were also reduced in a statistically significant dose-dependent manner in the highest dose group as compared with the epoetin alfa-treated group. Adverse events were similar for FG-4592-treated and control subjects. CONCLUSIONS: FG-4592 may prove an effective alternative for managing anemia of CKD. It is currently being investigated in a pivotal global Phase 3 program.

Induction of erythropoiesis by hypoxia-inducible factor prolyl hydroxylase inhibitors without promotion of tumor initiation, progression, or metastasis in a VEGF-sensitive model of spontaneous breast cancer.

The effects of pharmacological hypoxia-inducible factor (HIF) stabilization were investigated in the MMTV-Neundl-YD5 (NeuYD) mouse model of breast cancer. This study first confirmed the sensitivity of this model to increased vascular endothelial growth factor (VEGF), using bigenic NeuYD;MMTV-VEGF-25 mice. Tumor initiation was dramatically accelerated in bigenic animals. Bigenic tumors were also more aggressive, with shortened doubling times and increased lung metastasis as compared to NeuYD controls. In separate studies, NeuYD mice were treated three times weekly from 7 weeks of age until study end with two different HIF prolyl hydroxylase inhibitors (HIF-PHIs), FG-4497 or roxadustat (FG-4592). In NeuYD mice, HIF-PHI treatments elevated erythropoiesis markers, but no differences were detected in tumor onset or the phenotypes of established tumors.

Oral Hypoxia-Inducible Factor Prolyl Hydroxylase Inhibitor Roxadustat (FG-4592) for the Treatment of Anemia in Patients with CKD.

BACKGROUND AND OBJECTIVES: Roxadustat (FG-4592), an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that stimulates erythropoiesis, regulates iron metabolism, and reduces hepcidin, was evaluated in this phase 2b study for safety, efficacy, optimal dose, and dose frequency in patients with nondialysis CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: The 145 patients with nondialysis CKD and hemoglobin ≤10.5 g/dl were randomized into one of six cohorts of approximately 24 patients each with varying roxadustat starting doses (tiered weight and fixed amounts) and frequencies (two and three times weekly) followed by hemoglobin maintenance with roxadustat one to three times weekly. Treatment duration was 16 or 24 weeks. Intravenous iron was prohibited. The primary end point was the proportion of patients achieving hemoglobin increase of ≥1.0 g/dl from baseline and hemoglobin of ≥11.0 g/dl by week 17 (16 weeks of treatment). Secondary analyses included mean hemoglobin change from baseline, iron utilization, and serum lipids. Safety was evaluated by frequency/severity of adverse events. RESULTS: Of the 145 patients enrolled, 143 were evaluable for efficacy. Overall, 92% of patients achieved hemoglobin response. Higher compared with lower starting doses led to earlier achievement of hemoglobin response. Roxadustat-induced hemoglobin increases were independent of baseline C-reactive protein levels and iron repletion status. Overall, over the first 16 treatment weeks, hepcidin levels decreased by 16.9% (P=0.004), reticulocyte hemoglobin content was maintained, and hemoglobin increased by a mean (±SD) of 1.83 (±0.09) g/dl (P<0.001). Overall mean total cholesterol level was reduced by a mean (±SD) of 26 (±30) mg/dl (P<0.001) after 8 weeks of therapy, independent of the use of statins or other lipid-lowering agents. No drug-related serious adverse events were reported. CONCLUSIONS: In patients with nondialysis CKD who were anemic, various starting dose regimens of roxadustat were well tolerated and achieved anemia correction with reduced serum hepcidin levels. After anemia correction, hemoglobin was maintained by roxadustat at various dose frequencies without intravenous iron supplementation.

Roxadustat (FG-4592) Versus Epoetin Alfa for Anemia in Patients Receiving Maintenance Hemodialysis: A Phase 2, Randomized, 6- to 19-Week, Open-Label, Active-Comparator, Dose-Ranging, Safety and Exploratory Efficacy Study.

BACKGROUND: Roxadustat (FG-4592) is an oral hypoxia-inducible factor prolyl-hydroxylase inhibitor that promotes erythropoiesis through increasing endogenous erythropoietin, improving iron regulation, and reducing hepcidin. STUDY DESIGN: Phase 2, randomized (3:1), open-label, active-comparator, safety and efficacy study. SETTING & PARTICIPANTS: Patients with stable end-stage renal disease treated with hemodialysis who previously had hemoglobin (Hb) levels maintained with epoetin alfa. INTERVENTION: Part 1: 6-week dose-ranging study in 54 individuals of thrice-weekly oral roxadustat doses versus continuation of intravenous epoetin alfa. Part 2: 19-week treatment in 90 individuals in 6 cohorts with various starting doses and adjustment rules (1.0-2.0mg/kg or tiered weight based) in individuals with a range of epoetin alfa responsiveness. Intravenous iron was prohibited. OUTCOMES: Primary end point was Hb level response, defined as end-of-treatment Hb level change (ΔHb) of -0.5g/dL or greater from baseline (part 1) and as mean Hb level ≥ 11.0g/dL during the last 4 treatment weeks (part 2). MEASUREMENTS: Hepcidin, iron parameters, cholesterol, and plasma erythropoietin (the latter in a subset). RESULTS: Baseline epoetin alfa doses were 138.3±51.3 (SD) and 136.3±47.7U/kg/wk in part 1 and 152.8±80.6 and 173.4±83.7U/kg/wk in part 2, in individuals randomly assigned to roxadustat and epoetin alfa, respectively. Hb level responder rates in part 1 were 79% in pooled roxadustat 1.5 to 2.0mg/kg compared to 33% in the epoetin alfa control arm (P=0.03). Hepcidin level reduction was greater at roxadustat 2.0mg/kg versus epoetin alfa (P<0.05). In part 2, the average roxadustat dose requirement for Hb level maintenance was ∼1.7mg/kg. The least-squares-mean ΔHb in roxadustat-treated individuals was comparable to that in epoetin alfa-treated individuals (about -0.5g/dL) and the least-squares-mean difference in ΔHb between both treatment arms was -0.03 (95% CI, -0.39 to 0.33) g/dL (mixed effect model-repeated measure). Roxadustat significantly reduced mean total cholesterol levels, not observed with epoetin alfa. No safety concerns were raised. LIMITATIONS: Short treatment duration and small sample size. CONCLUSIONS: In this phase 2 study of anemia therapy in patients with end-stage renal disease on maintenance hemodialysis therapy, roxadustat was well tolerated and effectively maintained Hb levels.

Roxadustat (FG-4592): Correction of Anemia in Incident Dialysis Patients.

Safety concerns with erythropoietin analogues and intravenous (IV) iron for treatment of anemia in CKD necessitate development of safer therapies. Roxadustat (FG-4592) is an orally bioavailable hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor that promotes coordinated erythropoiesis through HIF-mediated transcription. We performed an open-label, randomized hemoglobin (Hb) correction study in anemic (Hb≤10.0 g/dl) patients incident to hemodialysis (HD) or peritoneal dialysis (PD). Sixty patients received no iron, oral iron, or IV iron while treated with roxadustat for 12 weeks. Mean±SD baseline Hb was 8.3±1.0 g/dl in enrolled patients. Roxadustat at titrated doses increased mean Hb by ≥2.0 g/dl within 7 weeks regardless of baseline iron repletion status, C-reactive protein level, iron regimen, or dialysis modality. Mean±SEM maximal change in Hb from baseline (ΔHb(max)), the primary endpoint, was 3.1±0.2 g/dl over 12 weeks in efficacy-evaluable patients (n=55). In groups receiving oral or IV iron, ΔHb(max) was similar and larger than in the no-iron group. Hb response (increase in Hb of ≥1.0 g/dl from baseline) was achieved in 96% of efficacy-evaluable patients. Mean serum hepcidin decreased significantly 4 weeks into study: by 80% in HD patients receiving no iron (n=22), 52% in HD and PD patients receiving oral iron (n=21), and 41% in HD patients receiving IV iron (n=9). In summary, roxadustat was well tolerated and corrected anemia in incident HD and PD patients, regardless of baseline iron repletion status or C-reactive protein level and with oral or IV iron supplementation; it also reduced serum hepcidin levels.

Randomized placebo-controlled dose-ranging and pharmacodynamics study of roxadustat (FG-4592) to treat anemia in nondialysis-dependent chronic kidney disease (NDD-CKD) patients.

BACKGROUND: Roxadustat (FG-4592) is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor that stimulates erythropoiesis. This Phase 2a study tested efficacy (Hb response) and safety of roxadustat in anemic nondialysis-dependent chronic kidney disease (NDD-CKD) subjects. METHODS: NDD-CKD subjects with hemoglobin (Hb) ≤11.0 g/dL were sequentially enrolled into four dose cohorts and randomized to roxadustat or placebo two times weekly (BIW) or three times weekly (TIW) for 4 weeks, in an approximate roxadustat:placebo ratio of 3:1. Efficacy was assessed by (i) mean Hb change (ΔHb) from baseline (BL) and (ii) proportion of Hb responders (ΔHb ≥ 1.0 g/dL). Pharmacodynamic evaluation was performed in a subset of subjects. Safety was evaluated by adverse event frequency/severity. RESULTS: Of 116 subjects receiving treatment, 104 completed 4 weeks of dosing and 96 were evaluable for efficacy. BL characteristics for roxadustat and placebo groups were comparable. In roxadustat-treated subjects, Hb levels increased from BL in a dose-related manner in the 0.7, 1.0, 1.5 and 2.0 mg/kg groups. Maximum ΔHb within the first 6 weeks was significantly higher in the 1.5 and 2.0 mg/kg groups than in the placebo subjects. Hb responder rates were dose dependent and ranged from 30% in the 0.7 mg/kg BIW group to 100% in the 2.0 mg/kg BIW and TIW groups versus 13% in placebo. CONCLUSIONS: Roxadustat transiently and moderately increased endogenous erythropoietin and reduced hepcidin. Adverse events were similar in the roxadustat and placebo groups. Roxadustat produced dose-dependent increases in blood Hb among anemic NDD-CKD patients in a placebo-controlled trial. CLINICAL TRIALS REGISTRATION: Clintrials.gov #NCT00761657.

Phase 1 study of anti-CTGF monoclonal antibody in patients with diabetes and microalbuminuria.

BACKGROUND AND OBJECTIVES: This report summarizes the first phase 1 trial treating patients with microalbuminuric diabetic kidney disease (DKD) using FG-3019, a human monoclonal antibody to connective tissue growth factor (CTGF). CTGF is critically involved in processes of progressive fibrosis, including DKD. This phase 1, open-label, dose-escalation trial evaluated safety, pharmacokinetics, and possible therapeutic effects of FG-3019 on albuminuria, proteinuria, and tubular proteins. DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS: Microalbuminuric subjects (n = 24) with type 2 (79%) or type 1 (21%) diabetes received 3 or 10 mg/kg FG-3019 dosed intravenously every 14 days for four doses. Albuminuria and safety follow-up were to days 62 and 365, respectively. RESULTS: No infusion was interrupted for symptoms, although 5 of 24 subjects had mild infusion-day adverse events thought to be possibly drug-related. No subject developed anti-FG-3019 antibodies. FG-3019 clearance was lower at 10 mg/kg than at 3 mg/kg, suggesting a saturable elimination pathway. Although this study was not designed for efficacy testing, it was notable that urinary albumin/creatinine ratio (ACR) decreased significantly from mean pretreatment ACR of 48 mg/g to mean post-treatment (day 56) ACR of 20 mg/g (P = 0.027) without evidence for a dose-response relationship. CONCLUSIONS: Treatment of microalbuminuric DKD subjects using FG-3019 was well tolerated and associated with a decrease in albuminuria. The data demonstrate a saturable pathway for drug elimination, minimal infusion adverse events, and no significant drug-attributable adverse effects over the year of follow-up. Changes in albuminuria were promising but require validation in a prospective, randomized, blinded study.