Optimization of HPLC method using central composite design for estimation of Torsemide and Eplerenone in tablet dosage form

Abstract A simple, precise, accurate and robust high performance liquid chromatographic method has been developed for simultaneous estimation of Torsemide and Eplerenone in tablet dosage form. Design of experiment was applied for multivariate optimization of the experimental conditions of RP-HPLC method. A Central composite design was used to study the response surface methodology and to analyse in detail the effects of these independent factors on responses. Total eleven experiments along with 3 center points were performed. Two factors were selected to design the matrix, one factor is variation in ratio of Acetonitrile and the second factor is flow rate (mL/min). Optimization in chromatographic conditions was achieved by applying Central composite design. The optimized and predicted data from contour diagram comprised mobile phase (acetonitrile, water and methanol in the ratio of 50: 30: 20 v/v/v respectively), at a flow rate of 1.0 ml/min and at ambient column temperature. Using these optimum conditions baseline separation of both drugs with good resolution and run time of less than 5 minutes were achieved. The optimized assay conditions were validated as per the ICH guidelines (2005). Hence, the results showed that the Quality by design approach could successfully optimize RP-HPLC method for simultaneous estimation of Torsemide and Eplerenone.

Effects of the NKCC1 inhibitors bumetanide, azosemide, and torasemide alone or in combination with phenobarbital on seizure threshold in epileptic and nonepileptic mice.

The sodium-potassium-chloride (Na-K-Cl) cotransporter NKCC1 is found in the plasma membrane of a wide variety of cell types, including neurons, glia and endothelial cells in the brain. Increased expression of neuronal NKCC1 has been implicated in several brain disorders, including neonatal seizures and epilepsy. The loop diuretic and NKCC inhibitor bumetanide has been evaluated as an antiseizure agent alone or together with approved antiseizure drugs such as phenobarbital (PB) in pre-clinical and clinical studies with varying results. The equivocal efficacy of bumetanide may be a result of its poor brain penetration. We recently reported that the loop diuretic azosemide is more potent to inhibit NKCC1 than bumetanide. In contrast to bumetanide, azosemide is not acidic, which should favor its brain penetration. Thus, azosemide may be a promising alternative to bumetanide for treatment of brain disorders such as epilepsy. In the present study, we determined the effect of azosemide and bumetanide on seizure threshold in adult epileptic mice. A structurally related non-acidic loop diuretic, torasemide, which also blocks NKCC1, was included in the experiments. The drug effects were assessed by determing the maximal electroshock seizure threshold (MEST) in epileptic vs. nonepileptic mice. Epilepsy was induced by pilocarpine, which was shown to produce long-lasting increases in NKCC1 in the hippocampus, whereas MEST did not alter NKCC1 mRNA in this region. None of the three loop diuretics increased MEST or the effect of PB on MEST in nonepileptic mice. In epileptic mice, all three diuretics significantly increased PB's seizure threshold increasing efficacy, but the effect was variable upon repeated MEST determinations and not correlated with the drugs' diuretic potency. These data may indicate that inhibition of NKCC1 by loop diuretics is not an effective means of increasing seizure threshold in adult epilepsy.

Rationale and Design of the Genotype-Blinded Trial of Torasemide for the Treatment of Hypertension (BHF UMOD).

BACKGROUND: Genome-wide association studies have identified single nucleotide polymorphisms (SNPs) near the uromodulin gene (UMOD) affecting uromodulin excretion and blood pressure (BP). Uromodulin is almost exclusively expressed in the thick ascending limb (TAL) of the loop of Henle and its effect on BP appears to be mediated via the TAL sodium transporter, NKCC2. Loop-diuretics block NKCC2 but are not commonly used in hypertension management. Volume overload is one of the primary drivers for uncontrolled hypertension, so targeting loop-diuretics to individuals who are more likely to respond to this drug class, using the UMOD genotype, could be an efficient precision medicine strategy. METHODS: The BHF UMOD Trial is a genotype-blinded, multicenter trial comparing BP response to torasemide between individuals possessing the AA genotype of the SNP rs13333226 and those possessing the G allele. 240 participants (≥18 years) with uncontrolled BP, on ≥1 antihypertensive agent for ≥3 months, will receive treatment with Torasemide, 5 mg daily for 16 weeks. Uncontrolled BP is average home systolic BP (SBP) >135 mmHg and/or diastolic BP >85 mmHg. The primary outcome is the change in 24-hour ambulatory SBP area under the curve between baseline and end of treatment. Sample size was calculated to detect a 4 mmHg difference between groups at 90% power. Approval by West of Scotland Research Ethics Committee 5 (16/WS/0160). RESULTS: The study should conclude August 2021. CONCLUSIONS: If our hypothesis is confirmed, a genotype-based treatment strategy for loop diuretics would help reduce the burden of uncontrolled hypertension. CLINICAL TRIALS REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT03354897.

Comparison between the effects of torsemide and furosemide on the renin-angiotensin-aldosterone system of normal dogs.

INTRODUCTION/OBJECTIVES: We hypothesized that torsemide and furosemide, at approximately equipotent dosages (similar diuresis), would have comparable effects on the circulating renin-angiotensin-aldosterone system. ANIMALS, MATERIALS AND METHODS: Six, healthy, middle-aged, male Beagles were randomized to receive torsemide (0.1 mg/kg PO q 12 h), furosemide (2.0 mg/kg PO q 12 h), or placebo for 10 days during three separate periods, separated by a 10-day washout period, in a crossover design. Blood was collected on days 1, 5, and 9 and 24-h urine collection ended on days 2, 6, and 10. After repeated measures analysis and Bonferonni correction, variables with an adjusted p<0.05 were investigated further, using Tukey's method. RESULTS: Twenty-four-hour urine production differed significantly between the diuretics only on day 10, with torsemide causing a 38% greater diuresis than furosemide. There was, however, no significant difference in average 3-day diuresis. There were no significant differences between diuretics in the 24-h urinary excretion of sodium, chloride, or potassium, though furosemide caused less kaliuresis than torsemide. Serum renin, angiotensin II, and aldosterone and the urine aldosterone-to-creatinine ratio were significantly increased in the diuretic groups, as compared to placebo on days 5/6 and 9/10. There were no significant differences in these values between diuretics. Creatinine and blood urea nitrogen concentrations rose comparably in the diuretic groups, remaining within reference intervals in all dogs. CONCLUSIONS: At approximately equipotent dosages (20:1), torsemide and furosemide produced comparable renin-angiotensin-aldosterone system activation. Torsemide's similar potassium excretion profile to furosemide decreases support for a hypothesized mineralocorticoid-receptor blocking capability.

A preliminary prospective study of patients who underwent vacuum-assisted and mesh-mediated fascial traction techniques for open abdomen management with negative fluid therapy: An observational study.

It is unclear whether strategies targeting negative fluid balance are associated with facilitated early fascial closure. The present study investigated the effects of fluid removal therapy on early facial closure of open abdomen patients.A prospective study was conducted in patients who underwent open abdomen management with vacuum-assisted and mesh-mediated fascial traction technique. Therapeutic diuresis with torasemide was applied to cause negative fluid balance in the treatment group. The study and follow-up periods were 7 and 180 days, respectively. The observational indices included the intra-abdominal pressure, the number of days to closure, the type of closure, the septic complications, the duration of ventilation support, the duration of initial hospital stay, and the duration of intensive care unit (ICU) stay.A total of 27 patients were divided into the treatment (16 patients) and control (11 patients) groups. The median intra-abdominal pressure (IAP) of the patients of the control and the treatment groups was significantly lower at day 7 compared with the baseline value (P < .0001). IAP was lower in the treatment group compared with that noted in the control group, following day 4 of the fluid removal therapy (P < .05). The percentage weight loss in the treatment group was between 4.80% and 10.88%. The early closure rates were significantly higher in the treatment group compared with those in the control group (75.0% vs 18.2%, P = .0063).Fluid removal therapy combined with vacuum-assisted and mesh-mediated fascial traction provided a high early fascial closure rate for open abdomen patients.

Evaluation of Y-site compatibility of home total parenteral nutrition and intravenous loop diuretics.

In chronic kidney disease (CKD), the design of the parenteral nutrition (PN) regimen becomes more challenging where only individualized PN is appropriate, coupled with the increased risk of unintended interactions with diuretic therapy. In an effort to ensure safe therapy in the home, we assessed the physical stability of bespoke PN formulations intended for use in CKD in the simultaneous presence of Y-site compatibility of furosemide and torasemide. The patient's daily needs were determined based on both metabolic demands as well as the demand for fluids.Complete admixtures were subjected to physical stability analysis consisting of visual inspection, a validated light microscope method, pH measurement, zeta potential measurement, and characterization of oily globule size distribution. Y-site compatibility of furosemide and torasemide with the formulated admixtures was also performed.The total parenteral admixture was stable over 7 days at +4°C and 24 h at +25°C and compatible via the Y-line together with furosemide and torasemide over 12 h at +25°C.The stability assessment guarantees the safety and efficiency of home PN with loop diuretics therapy in CKD patients. This means that these patients do not need long hospitalization and they can be safely treated at home. Furthermore, this study proved that torasemide is the same safety diuretic as furosemide, which has a great impact on clinical practice.

Torsemide versus furosemide after acute decompensated heart failure: a retrospective observational study.

BACKGROUND: Loop diuretics are recommended by clinical practice guidelines to treat volume overload in acute decompensated heart failure (ADHF). The effectiveness of switching furosemide to torsemide versus optimizing the furosemide dose following ADHF has not yet been evaluated. METHODS: This retrospective observational study aimed to assess the impact of switching furosemide to torsemide versus optimizing the furosemide dose after ADHF on HF-related hospitalization within 1 month and 6 months of discharge. The study included patients previously on furosemide admitted with ADHF to the Heart Hospital in Qatar between January 1, 2016 and June 30, 2017. The study included 2 groups: (1) patients discharged on torsemide; and (2) patients discharged on an optimized furosemide dose. Cox proportional hazard regression analysis was used to determine the association between diuretic use and hospitalization. RESULTS: Of the 232 patients included, 45 received torsemide and 187 received an optimized furosemide dose upon discharge. The majority of patients included were males (54%) with a mean age of 67 ± 12 years, and presented with HF with reduced ejection fraction (57%) and had a history of coronary artery disease (68%). The 1-month and 6-month HF-related hospitalization did not differ between the torsemide and optimized furosemide groups (aHR = 0.72; 95% CI 0.23-2.3, p = 0.57; aHR = 0.94, 95% CI 0.45-1.8, p = 0.87), respectively. CONCLUSION: Switching furosemide to torsemide after ADHF was not associated with reduced HF-related hospitalization compared to receiving an optimized furosemide dose. Larger prospective clinical trials are needed to confirm the findings of this study.

Investigating a biomarker-driven approach to target collagen turnover in diabetic heart failure with preserved ejection fraction patients. Effect of torasemide versus furosemide on serum C-terminal propeptide of procollagen type I (DROP-PIP trial).

AIM: Heart failure with preserved ejection fraction (HFpEF) is associated with myocardial remodelling including severe pro-fibrotic changes contributing to an increase in left ventricular stiffness and diastolic dysfunction. Serum C-terminal propeptide of procollagen type I (PIP) strongly correlates with the turnover of extracellular cardiac matrix proteins and fibrosis. Torasemide, but not furosemide, was described to reduce collagen type I synthesis in clinically unstable patients with heart failure with reduced ejection fraction. We evaluated whether its effect translated to HFpEF patients with type 2 diabetes mellitus (T2DM) and abnormal basal PIP levels. METHODS AND RESULTS: We performed a relatively small, single-centre, randomised, double-blind, two-arm parallel-group, active controlled clinical trial in 35 HFpEF patients with T2DM to determine the effects of a 9-month treatment with torasemide vs. furosemide on changes of serum PIP levels. Patients with increased PIP levels (≥110 ng/mL), or evidence of structural changes with a left atrial volume index (LAVI) >29 mL/m2 and abnormal PIP levels (≥70 ng/mL), were eligible to participate. Fifteen patients were female (42%), mean age was 69 years, body mass index was 34.7 kg/m2 , 83% were in New York Heart Association class II/III. Echocardiographic characteristics showed a mean left ventricular ejection fraction of >60%, a left ventricular mass index >120 g/m2 , an E/e' ratio of 14, and a LAVI of 40 mL/m2 with a NT-proBNP of 174 ng/L and a 6-minute walk distance of 421 m. Mean per cent change in PIP was 2.63 ± 5.68% (±SEM) in torasemide vs. 2.74 ± 6.49% in furosemide (P = 0.9898) treated patients. Torasemide was not superior to furosemide in improving functional capacity, diastolic function, quality of life, or neuroendocrine activation. CONCLUSION: In this hypothesis-generating, mechanistic trial in stable HFpEF patients with T2DM, neither long-term administration of torasemide nor furosemide was associated with a significant effect on myocardial fibrosis, as assessed by serum PIP. Further studies are urgently needed in this field. More specific diuretic and anti-fibrotic treatment strategies in T2DM and/or HFpEF are warranted.