Effects of Bumetanide on Neurocognitive Functioning in Children with Autism Spectrum Disorder: Secondary Analysis of a Randomized Placebo-Controlled Trial.

We present the secondary-analysis of neurocognitive tests in the 'Bumetanide in Autism Medication and Biomarker' (BAMBI;EUDRA-CT-2014-001560-35) study, a randomized double-blind placebo-controlled (1:1) trial testing 3-months bumetanide treatment (≤ 1 mg twice-daily) in unmedicated children 7-15 years with ASD. Children with IQ ≥ 70 were analyzed for baseline deficits and treatment-effects on the intention-to-treat-population with generalized-linear-models, principal component analysis and network analysis. Ninety-two children were allocated to treatment and 83 eligible for analyses. Heterogeneous neurocognitive impairments were found that were unaffected by bumetanide treatment. Network analysis showed higher modularity after treatment (mean difference:-0.165, 95%CI:-0.317 to - 0.013,p = .034) and changes in the relative importance of response inhibition in the neurocognitive network (mean difference:-0.037, 95%CI:-0.073 to - 0.001,p = .042). This study offers perspectives to include neurocognitive tests in ASD trials.

Bumetanide oral solution for the treatment of children and adolescents with autism spectrum disorder: Results from two randomized phase III studies.

The efficacy and safety of bumetanide oral solution for the treatment of autism spectrum disorder (ASD) in children and adolescents was evaluated in two international, multi-center, randomized, double-blind, placebo-controlled phase III trials; one enrolled patients aged 7-17 years (SIGN 1 trial) and the other enrolled younger patients aged 2-6 years (SIGN 2). In both studies, patients were randomized to receive bumetanide oral solution twice daily (BID) or placebo BID during a 6-month double-blind treatment period. The primary endpoint was change in Childhood Autism Rating Scale 2 (CARS2) total raw score from baseline to Week 26. Key secondary endpoints included changes in Social Responsiveness Scale-2, Clinical Global Impression Scale, and Vineland Adaptive Behavior Scale. Each study enrolled 211 patients (bumetanide, n = 107; placebo, n = 104). Both studies were terminated early due to absence of any significant difference between bumetanide and placebo in the overall studied populations. In both studies, CARS2 total raw score decreased from baseline to Week 26 in the bumetanide and placebo groups, with no statistically significant difference between groups. No differences were observed between treatment groups for any of the secondary efficacy endpoints in either study. In both studies, treatment-emergent adverse events that occurred more frequently with bumetanide than placebo included thirst, polyuria, hypokalemia, and dry mouth. These large phase III trials failed to demonstrate a benefit of bumetanide for the treatment of pediatric ASD compared with placebo. Consequently, the sponsor has discontinued the development of bumetanide for the treatment of this condition. Trial registration: https://clinicaltrials.gov: SIGN 1: NCT03715166; SIGN 2: NCT03715153.

Effects of bumetanide on neonatal seizures: A systematic review of animal and human studies.

BACKGROUND: Bumetanide, an inhibitor of the sodium-potassium-chloride cotransporter-1, has been suggested as an adjunct to phenobarbital for treating neonatal seizures. METHODS: A systematic review of animal and human studies was conducted to evaluate the efficacy and safety of bumetanide for neonatal seizures. PubMed, Embase, CINAHL and Cochrane databases were searched in March 2023. RESULTS: 26 animal (rat or mice) studies describing 38 experiments (28 in-vivo and ten in-vitro) and two human studies (one RCT and one open-label dose-finding) were included. The study designs, methods to induce seizures, bumetanide dose, and outcome measures were heterogeneous, with only 4/38 experiments being in animal hypoxia/ischaemia models. Among 38 animal experiments, bumetanide was reported to have antiseizure effects in 21, pro-seizure in six and ineffective in 11. The two human studies (n = 57) did not show the benefits of bumetanide as an add-on agent to phenobarbital in their primary analyses, but one study reported benefit on post-hoc analysis. Overall, hearing impairment was detected in 5/37 surviving infants in the bumetanide group vs. 0/13 in controls. Four of the five infants with hearing impairment had received aminoglycosides concurrently. Other adverse effects reported were diuresis, mild-to-moderate dehydration, hypotension, and electrolyte disturbances. The studies did not report on long-term neurodevelopment. The certainty of the evidence was very low. CONCLUSION: Animal data suggest that bumetanide has inconsistent effects as an antiseizure medication in neonates. Data from human studies are scarce and raise some concerns regarding ototoxicity when given with aminoglycosides. Well conducted studies in animal models of hypoxic-ischaemic encephalopathy are urgently needed. Future RCTs, if conducted in human neonates, should have an adequate sample size, assess neurodevelopment, minimize using aminoglycosides, be transparent about the potential ototoxicity in the parent information sheet, conduct early hearing tests and have trial-stopping rules that include hearing impairment as an outcome.

A Phase III Study of Bumetanide Oral Liquid Formulation for the Treatment of Children and Adolescents Aged Between 7 and 17 Years with Autism Spectrum Disorder (SIGN 1 Trial): Participant Baseline Characteristics.

The efficacy of bumetanide (oral liquid formulation 0.5 mg bid) as a treatment for the core symptoms of autism spectrum disorders in children and adolescents aged 7-17 years is being investigated in an international, randomised, double-blind, placebo-controlled phase III study. The primary endpoint is the change in Childhood Autism Rating Scale 2 (CARS2) total raw score after 6 months of treatment. At baseline, the 211 participants analysed are broadly representative of autistic subjects in this age range: mean (SD) age, 10.4 (3.0) years; 82.5% male; 47.7% with intelligence quotient ≥ 70. Mean CARS2 score was 40.1 (4.9) and mean Social Responsiveness Scale score was 116.7 (23.4). Final study results will provide data on efficacy and safety of bumetanide in autistic children and adolescents.

Bumetanide in autism spectrum disorder / Bumetanida no transtorno do espectro autista / Bumetanida en el trastorno del espectro autista

Objectives: This study aimed to make a bibliographic update on the already published data on bumetanide, addressing the main information on its use in Autism Spectrum Disorder (ASD). Methods: This was an integrative narrative review in which the following databases were used: Web of Science, MEDLINE, ScienceDirect, and Scielo. The descriptors used were: Autism Spectrum Disorder, Autistic Disorder and Bumetanide. It was considered only articles published in English and French. Original articles, randomized clinical trials, case reports, and review articles were included. Results: The results show that the use of bumetanide alters regions of the brain linked to the positive development of language, improvement of visual contact, improvement in social interactions, among others. Studies are also concerned about the safety and efficacy of bumetanide in ASD since several adverse effects have been reported. The most frequent were hypokalemia, polyuria, and loss of appetite. Conclusion: Bumetanide has proven as effective in improving some important symptoms in ASD, especially linked to language and social interaction, however, studies with larger groups of patients and with longer treatment and observation time are needed to confirm the efficacy and clarify the safety profile in use for people with ASD.

Objetivo: O objetivo deste trabalho foi fazer uma atualização bibliográfica sobre os dados já publicados da bumetanida, abordando as principais informações sobre seu uso no Transtorno do Espectro Autista (TEA). Metodologia: Foi realizada uma revisão do tipo narrativa integrativa, da qual foram utilizadas as bases de dados: Web of Science, MEDLINE, ScienceDirect e Scielo, com a utilização dos seguintes descritores: Autism Spectrum Disorder, Autistic Disorder e Bumetanide. Foram considerados apenas artigos publicados nas línguas inglesa e francesa. Foram incluídos artigos originais, ensaios clínicos randomizados e relatos de caso. Foram excluídos artigos de revisão. Resultados: Os resultados mostram que o uso da bumetanida altera regiões do cérebro ligadas ao desenvolvimento positivo da linguagem, melhora do contato visual, melhora nas interações sociais, entre outros. Os estudos também se preocupam em relacionar a segurança e a eficácia da bumetanida no TEA, do qual foram relatados diversos efeitos adversos, sendo os mais frequentes a hipocalemia, a poliúria e a perda de apetite. Conclusão: A bumetanida mostrou ser eficaz na melhoria de alguns importantes sintomas no TEA, especialmente ligados à linguagem e interação social, entretanto, estudos com grupos maiores de pacientes e com maior tempo de tratamento e observação são necessários para confirmar a eficácia e esclarecer o perfil de segurança no uso para pessoas com TEA.

: Este estudio tuvo como objetivo realizar una actualización bibliográfica sobre los datos ya publicados sobre la bumetanida, abordando la principal información sobre su uso en el Trastorno del Espectro Autista (TEA). Métodos: Se trata de una revisión narrativa integradora en la que se utilizaron las siguientes bases de datos: Web of Science, MEDLINE, ScienceDirect y Scielo. Los descriptores utilizados fueron: Trastorno del Espectro Autista, Trastorno Autista y Bumetanida. Se consideraron sólo los artículos publicados en inglés y francés. Se incluyeron artículos originales, ensayos clínicos aleatorios, informes de casos y artículos de revisión. Resultados: Los resultados muestran que el uso de la bumetanida altera regiones del cerebro relacionadas con el desarrollo positivo del lenguaje, la mejora del contacto visual, la mejora de las interacciones sociales, entre otros. Los estudios también se preocupan por la seguridad y eficacia de la bumetanida en el TEA, ya que se han reportado varios efectos adversos. Los más frecuentes fueron la hipocalemia, la poliuria y la pérdida de apetito. Conclusiones: La bumetanida ha demostrado ser eficaz en la mejora de algunos síntomas importantes en el TEA, especialmente vinculados al lenguaje y la interacción social, sin embargo, se necesitan estudios con grupos más grandes de pacientes y con mayor tiempo de tratamiento y observación para confirmar la eficacia y aclarar el perfil de seguridad en el uso para personas con TEA.

Pain Associated With Continuous Intravenous Infusion of Bumetanide: A Case Series.

INTRODUCTION: Bumetanide can induce generalized musculoskeletal pain when administered as a continuous infusion, an effect that may be underrecognized. The purpose of this case series is to educate health care providers about the incidence and presentation of pain associated with bumetanide infusions, adding to the existing literature describing this adverse event. CLINICAL FINDINGS: Of 40 critically ill patients, 15 (38%) had increased pain scores after initiation of a continuous infusion of bumetanide, with symptoms commonly occurring 12 to 24 hours after initiation of the infusion. Reported descriptions of the pain included generalized aching, soreness, burning, allodynia, headaches, and exacerbation of underlying pain in localized areas. Increases in patient-reported pain correlated directly with initiation of the continuous infusion of bumetanide. DIAGNOSIS: Four of the 15 bumetanide-associated pain events (27%) were recognized as such by the health care team. INTERVENTIONS: Bumetanide was promptly discontinued in the 4 identified cases. The 11 patients (73%) whose pain was not recognized as related to bumetanide remained on a continuous infusion of bumetanide and received pain medications including opioids. Infusions were stopped when patients transitioned to dialysis (n = 8 [53%]), began receiving comfort care (n = 5 [33%]), or completed diuresis therapy (n = 2 [13%]). OUTCOMES: For all patients, pain symptoms resolved within 24 to 48 hours after discontinuation of bumetanide infusion with no significant electrolyte abnormalities. CONCLUSION: Bumetanide-induced pain is more common than previously described. Early recognition of this adverse event can prevent patient discomfort and escalation of treatment.

Improved symptoms following bumetanide treatment in children aged 3-6 years with autism spectrum disorder: a randomized, double-blind, placebo-controlled trial.

With the current limited drug therapy for the core symptoms of autism spectrum disorder (ASD), we herein report a randomized, double-blind, placebo-controlled trial to investigate the efficacy, safety, and potential neural mechanism of bumetanide in children with ASD aged 3-6 years old. A total of 120 children were enrolled into the study and randomly assigned to either 0.5 mg bumetanide or placebo. In the final sample, 119 children received at least one dose of bumetanide (59 children) or placebo (60 children) were included in the final analysis. The primary outcome was a reduction in the Childhood Autism Rating Scale (CARS) score, and the secondary outcomes were the Clinical Global Impressions Scale (CGI) -Global Improvement (CGI-I) score at 3 months and the change from baseline to 3-month in the Autism Diagnostic Observation Schedule (ADOS). Magnetic resonance spectroscopy (MRS) was used to measure γ-aminobutyric acid (GABA) and glutamate neurotransmitter concentrations in the insular cortex (IC) before and after the treatment. As compared with the placebo, bumetanide treatment was significantly better in reducing the severity. No patient withdrew from the trial due to adverse events. The superiority of bumetanide to placebo in reducing insular GABA, measured using MRS, was demonstrated. The clinical improvement was associated with a decrease in insular GABA in the bumetanide group. In conclusion, this trial in a large group of young children with predominantly moderate and severe ASD demonstrated that bumetanide is safe and effective in improving the core symptoms of ASD. However, the clinical significance remains uncertain, and future multi-center clinical trials are required to replicate these findings and confirm the clinical significance using a variety of outcome measures.

Bumetanide for Core Symptoms of Autism Spectrum Disorder (BAMBI): A Single Center, Double-Blinded, Participant-Randomized, Placebo-Controlled, Phase-2 Superiority Trial.

OBJECTIVE: Recent trials have indicated positive effects of bumetanide in autism spectrum disorder (ASD). We tested efficacy of bumetanide on core symptom domains using a single center, parallel-group, participant-randomized, double-blind, placebo-controlled phase-2 superiority trial in a tertiary hospital in the Netherlands. METHOD: Unmedicated children aged 7 to 15 years with ASD and IQ ≥55 were block-randomized 1:1 to oral-solution bumetanide versus placebo, titrated to a maximum of 1.0 mg twice daily for 91 days (D91), followed by a 28-day wash-out period. The primary outcome was difference in Social Responsiveness Scale-2 (SRS-2) total score at D91, analyzed by modified intention-to-treat with linear mixed models. RESULTS: A total of 92 participants (mean age 10.5 [SD 2.4] years) enrolled between June 2016 and December 2018. In all, 47 children were allocated to bumetanide and 45 to placebo. Two participants dropped out per treatment arm. After 91 days, bumetanide was not superior to placebo on the primary outcome, the SRS-2 (mean difference -3.16, 95% CI = -9.68 to 3.37, p = .338). A superior effect was found on one of the secondary outcomes, the Repetitive Behavior Scale-Revised (mean difference -4.16, 95% CI = -8.06 to -0.25, p = .0375), but not on the Sensory Profile (mean difference 5.64, 95% CI = -11.30 to 22.57, p = .508) or the Aberrant Behavior Checklist Irritability Subscale (mean difference -0.65, 95% CI = -2.83 to 1.52, p = .552). No significant wash-out effect was observed. Significant adverse effects were predominantly diuretic effects (orthostatic hypotension (17 [36%] versus 5 [11%], p = .007); hypokalemia (24 [51%] versus 0 [0%], p < .0001), the occurrence of which did not statistically influence treatment outcome. CONCLUSION: The trial outcome was negative in terms of no superior effect on the primary outcome. The secondary outcomes suggest efficacy on repetitive behavior symptoms for a subset of patients. CLINICAL TRIAL REGISTRATION INFORMATION: Bumetanide in Autism Medication and Biomarker Study (BAMBI); https://www.clinicaltrialsregister.eu/; 2014-001560-35.

Editorial: Targeting the Core Symptoms of Autism Spectrum Disorder With Mechanism-Based Medications.

Medications can help manage behavioral problems associated with autism spectrum disorder (ASD), but no pharmacological treatment has proved effective for the core symptoms of the disorder. The article by Sprengers et al.1 in this issue of the Journal reports the primary results of the randomized clinical trial Bumetanide in Autism Medication and Biomarker (BAMBI), which tested the efficacy of bumetanide, a loop diuretic acting as a selective antagonist of the chloride importer NKCC1, for the core symptoms of ASD in 92 children 7-15 years of age.1 The study by Sprengers and colleagues was carefully designed and powered to detect a medium treatment effect size. Great attention was paid to protecting the blindness of the experiment in light of the adverse effects of the medication. After the 3-month treatment, bumetanide was not better than placebo at decreasing social communication deficits, as measured with the Social Responsiveness Scale-2 (the primary outcome), although a decrease in repetitive behaviors (a secondary outcome) was found. This study attests to the progress from clinical serendipity to pathogenesis-driven treatment research in ASD and is remarkable in a number of ways.

DRESS syndrome following furosemide administration: An unusual association.

INTRODUCTION: Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe and rare adverse drug reaction. Several drugs are known to induce DRESS. Furosemide, a sulfonamide loop diuretic drug, is known to induce hypersensitive reactions such as bullous eruptions, acute generalized exanthematous pustulosis and lichenoid eruptions, but rarely DRESS. We describe herein a case of furosemide-induced DRESS that recurred after bumetanide administration. CASE REPORT: A 67-year-old man was admitted to the nephrology department for hypertension, gout and chronic renal failure. He received a multidrug therapy including captopril, nifedipine, allopurinol and furosemide. Six weeks after starting this treatment, he developed a maculopapular itchy and edematous skin reaction, facial edemaand fever. The laboratory findings showed 2200/mm3 of eosinophils (20%). Creatinine clearance decreased from 18.9 to 14.4 mL/min. Lactate dehydrogenase was at 600 IU/L (normal range 190-390 IU/L). Chest X-ray showed an interstitial lung injury. Skin biopsy findings were in accordance with a hypersensitive reaction. Furosemide was withdrawn and symptoms resolved completely three weeks later. A patch test with furosemide performed six weeks later was negative. The patient was given bumetanide, another sulfonamide loop diuretic, with recurrence of symptoms two months later. Bumetanide was withdrawn with a complete resolution of both clinical and biological symptoms within three weeks. CONCLUSION: We add to the literature another case of furosemide-induced DRESS with the particularity of cross reactivity with bumetanide.

Treatment outcomes of bumetanide continuous infusion: A systematic review and meta-analysis.

The clinical use of continuous bumetanide infusion for acute heart failure and volume overload is common. However, there is not enough supporting evidence for the use of continuous bumetanide infusion. Thus, we conducted this systematic review and meta-analysis aiming to describe the treatment outcomes of continuous bumetanide infusion. We searched Ovid MEDLINE, EMBASE and the Cochrane Library for eligible publications. Inclusion criteria were patients age ≥18 years with bumetanide infusion for heart failure, acute kidney injury (AKI) or volume overload. From 1564 citations, three studies (n = 94 patients) were included in the systematic review and meta-analysis. The mean dose of bumetanide was 1.08 ± 0.43 mg/hour with a mean treatment duration of 45.09 ± 10.12 hours. Mean urine output in response to continuous bumetanide infusion was 1.88 mL/kg/hour (95% confidence interval [CI], 1.72-2.05). The incidence of AKI with continuous bumetanide infusion was 24.7% (95% CI, 8.2-54.6). By using Pearson's correlation coefficient, increasing doses of bumetanide were correlated with increased urine output (P = .026) and increased incidence of AKI (P < .01). There was no correlation between increasing urine output and the incidence of AKI (P = .739). In conclusion, with available evidence, continuous bumetanide infusion may be used in the treatment of acute heart failure or volume overload with close monitoring for new-onset or worsening AKI.

BRASH syndrome.

A 62-year-old woman with chronic kidney disease stage 4, sleep apnoea on continuous positive airway pressure and recent admission for acute-on-chronic diastolic heart failure presented to emergency room with weakness. She was hypotensive and had symptomatic bradycardia in the 30 s secondary to hyperkalaemia and beta-blockers, raising concern for BRASH syndrome. Antihypertensives were immediately held. Potassium-lowering agents (with calcium gluconate for cardiac stability) were begun, as were fluids and dopamine for vasopressor support. The patient was admitted to intensive care unit and electrophysiology was consulted. Over the next 2 days, the patient clinically improved: she remained off dopamine for over 24 hours; potassium levels and renal function improved; and heart rate stabilised in 60 s. The patient was eventually discharged and advised to avoid metolazone, bumetanide and carvedilol, with primary care provider and cardiology follow-up.

Impaired chloride homeostasis in epilepsy: Molecular basis, impact on treatment, and current treatment approaches.

Epilepsies represent one of the most common neurological diseases worldwide. They are characterized by recurrent spontaneous seizures with severe impact on a patient's life. An imbalance in excitatory and inhibitory signalling is considered the main underlying pathophysiological mechanism. Therefore, GABA-mimetic drugs, strengthening the main inhibitory signalling system in the CNS, are frequently used as antiepileptic or anticonvulsant drugs. However, the therapeutic effect of such treatment depends on the chloride gradient along the plasma membrane. Impairment of chloride homeostasis, caused by alterations in the functional balance of chloride transporters, was implicated in the pathophysiology of epilepsy and numerous other diseases. Breakdown or even inversion of the chloride gradient may result in ineffective or in worst cases proconvulsant effects of GABA-mimetics. Unfortunately, such situations are reported in considerable number. Consequently, bumetanide, an inhibitor of Na-K-Cl cotransporters gained interest as potential add-on therapy re-establishing the chloride gradient and thereby the hyperpolarizing effects of GABA-mimetic drugs. Indeed, preclinical studies yielded encouraging results, especially when applied in combination with GABA-mimetics in epilepsy models. However, bumetanide induces a strong diuretic effect and displays poor penetration across the blood-brain barrier, two adverse features for chronic antiepileptic treatment. Therefore, new compounds overcoming these limitations are under development. This review focuses on alterations in chloride homeostasis and its underlying molecular mechanisms in epilepsy, on the potential impact of impaired chloride homeostasis on the treatment of epilepsy and on concepts to overcome this problem including recent development of bumetanide derivatives with improved pharmacological profile.

Evaluation of Severe Myalgia Induced by Continuous-Infusion Bumetanide in Patients with Acute Heart Failure.

STUDY OBJECTIVES: Continuous intravenous (IV) infusion bumetanide has been associated with severe myalgia in case reports, and the package labeling lists a reported incidence of 0.2% for severe myalgia. The primary objective of this study was to quantify the incidence of bumetanide infusion-induced severe myalgia in patients with acute heart failure (AHF). Secondary objectives were to assess a dose-response relationship between bumetanide infusion rate and occurrence of myalgia and to investigate potential risk factors associated with bumetanide-induced myalgia. DESIGN: Retrospective analysis. SETTING: Large academic medical center. PATIENTS: Adults hospitalized with AHF who required bumetanide (≥ 0.5 mg/hr [464 patients]) or furosemide (≥ 20 mg/hr [197 patients]) by continuous IV infusion between September 2015 and May 2017. MEASUREMENTS AND MAIN RESULTS: The incidence of severe myalgia with IV furosemide infusion was assessed to measure confounding by indication bias. Electronic medical records were used to identify patients exposed to bumetanide 0.25-mg/ml or furosemide 2-mg/ml continuous IV infusions. We defined severe myalgia as a diffuse myalgia with a physician's documented suspicion of bumetanide- or furosemide-induced myalgia unresponsive to electrolyte repletion and necessitating a change to alternative diuretics. The incidence of severe myalgia during bumetanide therapy was 5.8%, with the incidence increasing with higher bumetanide infusion rates: 2.6% for an infusion rate ≤ 1 mg/hour and 10.3% for a rate > 1 mg/hour (p=0.0005). In the multivariate logistic regression analysis, a bumetanide infusion rate > 1 mg/hour was independently associated (odds ratio 4.8, 95% confidence interval 1.94-12.02, p=0.0007) with severe myalgia compared to that with a rate ≤ 1 mg/hour. No patients receiving furosemide continuous IV infusion experienced severe myalgia, although infusion rates were lower in potency than bumetanide infusion rates. CONCLUSION: The incidence of severe myalgia in patients with AHF receiving bumetanide infusion was 5.8%, 29-fold higher than incidence rate listed in the package labeling. Patients receiving infusion rates > 1 mg/hour were 4-fold more likely to experience bumetanide-induced severe myalgia than those receiving rates ≤ 1 mg/hour.

Acetazolamide to increase natriuresis in congestive heart failure at high risk for diuretic resistance.

AIMS: To investigate the effects of acetazolamide on natriuresis, decongestion, kidney function and neurohumoral activation in acute heart failure (AHF). METHODS AND RESULTS: This prospective, two-centre study included 34 AHF patients on loop diuretics with volume overload. All had a serum sodium concentration < 135 mmol/L and/or serum urea/creatinine ratio > 50 and/or an admission serum creatinine increase of > 0.3 mg/dL compared to baseline. Patients were randomised towards acetazolamide 250-500 mg daily plus bumetanide 1-2 mg bid vs. high-dose loop diuretics (bumetanide bid with daily dose twice the oral maintenance dose). The primary endpoint was natriuresis after 24 h. Natriuresis after 24 h was similar in the combinational treatment vs. loop diuretic only arm (264 ± 126 vs. 234 ± 133 mmol; P = 0.515). Loop diuretic efficiency, defined as natriuresis corrected for loop diuretic dose, was higher in the group receiving acetazolamide (84 ± 46 vs. 52 ± 42 mmol/mg bumetanide; P = 0.048). More patients in the combinational treatment arm had an increase in serum creatinine levels > 0.3 mg/dL (P = 0.046). N-terminal pro-B-type natriuretic peptide reduction and peak neurohumoral activation within 72 h were comparable among treatment arms. There was a non-significant trend towards lower all-cause mortality or heart failure readmissions in the group receiving acetazolamide with low-dose loop diuretics vs. high-dose loop diuretic monotherapy (P = 0.098). CONCLUSION: Addition of acetazolamide increases the natriuretic response to loop diuretics compared to an increase in loop diuretic dose in AHF at high risk for diuretic resistance. TRIAL REGISTRATION: ClinicalTrials.gov NCT01973335.

A Preliminary Study Evaluating the Safety and Efficacy of Bumetanide, an NKCC1 Inhibitor, in Patients with Drug-Resistant Epilepsy.

BACKGROUND: Dysregulation of cation-chloride cotransporters NKCC1 and KCC2 expression was shown to be related to drug-resistant epilepsy. Previous studies suggested that bumetanide, an inhibitor of NKCC1, might have antiepileptic effects. OBJECTIVE: The aim of this study was to investigate the safety and efficacy of bumetanide add-on therapy in patients with drug-resistant epilepsy and its relation to cation-chloride cotransporters NKCC1 and KCC2. METHODS: We conducted an open-label, single-arm clinical trial in drug-resistant temporal lobe epilepsy (TLE) patients. This study consisted of three phases: pretreatment (3 months), titration (3 weeks), and active treatment (6 months). During the pretreatment phase, the dose of antiepileptic drugs was stabilized, and bumetanide was then added at an initial dose of 0.5 mg/day, increasing by 0.5 mg/week until a target dose of 2 mg/day was achieved. Bumetanide treatment was then continued for 6 months. Seizure frequency and adverse events were assessed at every monthly visit. Blood samples were collected from patients and 12 healthy controls were used for polymerase chain reaction and Western blot analyses. Primary clinical outcomes were drug safety and change in seizure frequency. Changes in NKCC1 and KCC2 expression were the non-clinical endpoints. RESULTS: A total of 30 patients were enrolled, 27 of whom completed the study. The mean duration of epilepsy was 16.5 years. Median seizure frequency per month was 9 [interquartile range (IQR) 7-14.5] at baseline, 3.67 (IQR 1.84-6.17) at the first 3 months, and 2 (IQR 0.84-4.34) at the last 3 months (p < 0.001). Five adverse events were detected in six patients. The reported adverse events were anorexia in four patients, nausea and vomiting in two patients, and agitation, headache and increased seizure frequency in one patient each. The level of NKCC1 and KCC2 gene transcripts and KCC2 protein did not change significantly following treatment (p > 0.05); however, we observed a significant reduction in NKCC1 protein levels (p = 0.042). CONCLUSIONS: Bumetanide might be an effective and relatively tolerable drug in patients with drug-resistant TLE. Downregulation of NKCC1 protein following bumetanide treatment may be responsible for its antiepileptic effects. IRANIAN REGISTRY OF CLINICAL TRIALS IDENTIFIER: IRCT 201012115368N1.

Interaction Between the Sodium-Glucose-Linked Transporter 2 Inhibitor Dapagliflozin and the Loop Diuretic Bumetanide in Normal Human Subjects.

BACKGROUND: Dapagliflozin inhibits the sodium-glucose-linked transporter 2 in the renal proximal tubule, thereby promoting glycosuria to reduce hyperglycemia in type 2 diabetes mellitus. Because these patients may require loop diuretics, and sodium-glucose-linked transporter 2 inhibition causes an osmotic diuresis, we evaluated the diuretic interaction between dapagliflozin and bumetanide. METHODS AND RESULTS: Healthy subjects (n=42) receiving a fixed diet with ≈110 mmol·d-1 of Na+ were randomized to bumetanide (1 mg·d-1), dapagliflozin (10 mg·d-1), or both for 7 days, followed by 7 days of both. There were no meaningful pharmacokinetic interactions. Na+ excretion increased modestly with the first dose of dapagliflozin (22±6 mmol·d-1; P<0.005) but by more (P<0.005) with the first dose of bumetanide (74±7 mmol·d-1; P<0.005), which was not significantly different from both diuretics together (80±5 mmol·d-1; P<0.005). However, Na+ excretion with dapagliflozin was 190% greater (P<0.005) when added after 1 week of bumetanide (64±6 mmol·d-1), and Na+ excretion with bumetanide was 36% greater (P<0.005) when added after 1 week of dapagliflozin (101±8 mmol·d-1). Serum urate was increased 4% by bumetanide but reduced 40% by dapagliflozin or 20% by combined therapy (P<0.05). CONCLUSIONS: First-dose Na+ excretion with bumetanide and dapagliflozin is not additive, but the weekly administration of one diuretic enhances the initial Na+ excretion with the other, thereby demonstrating mutual adaptive natriuretic synergy. Combined therapy reverses bumetanide-induced hyperuricemia. This requires further study in diabetic patients with hyperglycemia who have enhanced glycosuria and natriuresis with dapagliflozin. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT00930865.

NKCC1 Chloride Importer Antagonists Attenuate Many Neurological and Psychiatric Disorders.

In physiological conditions, adult neurons have low intracellular Cl- [(Cl-)I] levels underlying the γ-aminobutyric acid (GABA)ergic inhibitory drive. In contrast, neurons have high (Cl-)I levels and excitatory GABA actions in a wide range of pathological conditions including spinal cord lesions, chronic pain, brain trauma, cerebrovascular infarcts, autism, Rett and Down syndrome, various types of epilepsies, and other genetic or environmental insults. The diuretic highly specific NKCC1 chloride importer antagonist bumetanide (PubChem CID: 2461) efficiently restores low (Cl-)I levels and attenuates many disorders in experimental conditions and in some clinical trials. Here, I review the mechanisms of action, therapeutic effects, promises, and pitfalls of bumetanide.

Rapid and Highly Accurate Prediction of Poor Loop Diuretic Natriuretic Response in Patients With Heart Failure.

BACKGROUND: Removal of excess sodium and fluid is a primary therapeutic objective in acute decompensated heart failure and commonly monitored with fluid balance and weight loss. However, these parameters are frequently inaccurate or not collected and require a delay of several hours after diuretic administration before they are available. Accessible tools for rapid and accurate prediction of diuretic response are needed. METHODS AND RESULTS: Based on well-established renal physiological principles, an equation was derived to predict net sodium output using a spot urine sample obtained 1 or 2 hours after loop diuretic administration. This equation was then prospectively validated in 50 acute decompensated heart failure patients using meticulously obtained timed 6-hour urine collections to quantify loop diuretic-induced cumulative sodium output. Poor natriuretic response was defined as a cumulative sodium output of <50 mmol, a threshold that would result in a positive sodium balance with twice-daily diuretic dosing. Following a median dose of 3 mg (2-4 mg) of intravenous bumetanide, 40% of the population had a poor natriuretic response. The correlation between measured and predicted sodium output was excellent (r=0.91; P<0.0001). Poor natriuretic response could be accurately predicted with the sodium prediction equation (area under the curve =0.95, 95% confidence interval 0.89-1.0; P<0.0001). Clinically recorded net fluid output had a weaker correlation (r=0.66; P<0.001) and lesser ability to predict poor natriuretic response (area under the curve =0.76, 95% confidence interval 0.63-0.89; P=0.002). CONCLUSIONS: In patients being treated for acute decompensated heart failure, poor natriuretic response can be predicted soon after diuretic administration with excellent accuracy using a spot urine sample.

Pilot evaluation of the population pharmacokinetics of bumetanide in term newborn infants with seizures.

Recent experimental data suggest bumetanide as a possible therapeutic option in newborn infants with seizures after birth asphyxia. Because pharmacokinetic (PK) data are lacking in this population, who very often benefit from therapeutic cooling, which can modify the PK behavior of a drug, a PK study was conducted in term infants with seizures caused by hypoxic-ischemic encephalopathy. Fourteen infants were included, 13 of them being cooled. Forty-nine blood samples were available for the determination of the plasma concentration of bumetanide. Concentration-time data were analyzed by the use of a population approach performed with Monolix Software. Bumetanide was found to follow a 2-compartment model. The mean values were 0.063 L/h for clearance, 0.28 and 0.44 L for the central and peripheral distribution volumes, respectively, and 0.59 L/h for the distribution clearance. Birth body weight explained the interindividual variability of bumetanide clearance via an allometric model. No relationship was found between bumetanide exposure and its efficacy (reduction in seizure burden) or its toxicity (hearing loss). This study describes the first PK model of bumetanide in hypothermia-treated infants with seizures.