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74 result(s) for "Losartan - pharmacokinetics"
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Pharmacokinetics of a Fixed-Dose Combination Product of Amlodipine, Losartan, Ezetimibe, and Rosuvastatin and Its Comparison with Co-administration of Four Individual Components in Healthy Participants
Background and Objective This study aimed to assess and compare the pharmacokinetics, safety, and tolerability of a fixed-dose combination product (FDCP) comprising four different drugs (two antihypertensive drugs, amlodipine and losartan, and two lipid-lowering agents, ezetimibe and rosuvastatin) with their separate tablets. Methods A total of 60 participants were enrolled in this open-label, randomized, single-dose crossover study. Each participant received a single dose of FDCP and individual tablets during each period, with a 14-day washout period between the periods. The pharmacokinetic parameters of amlodipine, losartan, EXP3174 (an active metabolite of losartan), rosuvastatin, free ezetimibe, and total ezetimibe were evaluated and compared. Results The pharmacokinetic profiles of amlodipine, losartan, rosuvastatin, and ezetimibe after administration of the individual products were similar to those of FDCP. The geometric mean ratios and 90% confidence intervals for maximum concentration ( C max ) and area under the curve (AUC) of FDCP to individual tablets were within 0.8–1.25 for all six analytes. No clinically relevant changes were observed in the vital signs or physical, biochemical, hematological, electrocardiographic, or urinalysis findings during the study, and no serious adverse events were reported. Conclusion This study demonstrated that a newly developed FDCP containing amlodipine, losartan, ezetimibe, and rosuvastatin exhibited pharmacokinetic equivalence with the individual products and met the regulatory criteria. Both formulations were well tolerated. Clinical Trial Registration This trial (NCT04322266) was retrospectively registered on 9 September 2019.
Telmisartan is more effective than losartan in reducing proteinuria in patients with diabetic nephropathy
In patients with diabetic nephropathy, lowering blood pressure and reducing proteinuria by over 30% correlates with a slower progression to kidney failure. We compared two different angiotensin receptor-blockers in a double blind, prospective trial of 860 patients with type 2 diabetes whose blood pressure levels was over 130/80mmHg or who were receiving antihypertensive medication(s) and who had a morning spot urinary protein to creatinine ratio of 700 or more. Patients were randomized to telmisartan (a highly lipophilic agent with a long half-life) or losartan (with low lipophilicity and short half-life). The primary endpoint was the difference in the urinary albumin to creatinine ratio between the groups at 52 weeks. The geometric coefficient of variation and the mean of the urinary albumin to creatinine ratio fell in both groups at 52 weeks but both were significantly greater for the telmisartan compared to the losartan cohort. Mean systolic blood pressure reductions were not significantly different between groups at trial end. We conclude that telmisartan is superior to losartan in reducing proteinuria in hypertensive patients with diabetic nephropathy, despite a similar reduction in blood pressure.
Effect of commercial Rhodiola rosea on CYP enzyme activity in humans
Purpose The aim of the present study was to evaluate the effect of the herbal drug Rhodiola rosea on the activity of the cytochrome P-450 (CYP) enzymes CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 in humans. Methods In a randomized cross-over study, 13 healthy volunteers were given a cocktail with single doses of the CYP substrates caffeine (CYP1A2), losartan (CYP2C9), omeprazole (CYP2C19), dextromethorphan (CYP2D6), and midazolam (CYP3A4) with and without 14 days of pretreatment with a commercially available R. rosea product (Arctic Root, produced by the Swedish Herbal Institute). Four hours after intake of the drug cocktail, a blood sample was obtained, the serum concentrations of the drugs and their metabolites were analyzed, and the metabolic ratios were calculated as a measure of CYP enzyme activity. Results A statistically significant 21 % decrease in the EXP-3174/losartan ratio was found after pretreatment with R. rosea ( p  = 0.023), indicating a reduced CYP2C9 metabolic activity. The effect was more pronounced in CYP2C9 extensive metabolizers than in CYP2C9 intermediate and poor metabolizers. For the other CYP enzymes tested, no significant effects were observed. Conclusions This study indicates that R. rosea inhibits the metabolic capacity of CYP2C9 in humans. Although the effect is modest, it might be clinically relevant during treatment with CYP2C9 substrates with a narrow therapeutic index, such as phenytoin and warfarin.
Drug–drug interactions between sucroferric oxyhydroxide and losartan, furosemide, omeprazole, digoxin and warfarin in healthy subjects
Background The novel iron-based phosphate binder sucroferric oxyhydroxide is being investigated for the treatment of hyperphosphatemia. Patients with chronic kidney disease often have multiple comorbidities that may necessitate the daily use of several types of medication. Therefore, the potential pharmacokinetic drug–drug interactions between sucroferric oxyhydroxide and selected drugs commonly taken by dialysis patients were investigated. Methods Five Phase I, single-center, open-label, randomized, three-period crossover studies in healthy volunteers investigated the effect of a single dose of sucroferric oxyhydroxide 1 g (based on iron content) on the pharmacokinetics of losartan 100 mg, furosemide 40 mg, omeprazole 40 mg, digoxin 0.5 mg and warfarin 10 mg. Pharmacokinetic parameters [including area under the plasma concentration–time curve (AUC) from time 0 extrapolated to infinite time (AUC 0–∞ ) and from 0 to 24 h (AUC 0–24 )] for these drugs were determined: alone in the presence of food; with sucroferric oxyhydroxide in the presence of food; 2 h after food and sucroferric oxyhydroxide administration. Results Systemic exposure based on AUC 0–∞ for all drugs, and AUC 0–24 for all drugs except omeprazole (for which AUC 0–8 h was measured), was unaffected to a clinically significant extent by the presence of sucroferric oxyhydroxide, irrespective of whether sucroferric oxyhydroxide was administered with the drug or 2 h earlier. Conclusions There is a low risk of drug–drug interactions between sucroferric oxyhydroxide and losartan, furosemide, digoxin and warfarin. There is also a low risk of drug–drug interaction with omeprazole (based on AUC 0–∞ values). Therefore, sucroferric oxyhydroxide may be administered concomitantly without the need to adjust the dosage regimens of these drugs.
Comparison of Pharmacokinetics of a Fixed-Dose Combination of Amlodipine/Losartan/Rosuvastatin with Concomitant Administration of Amlodipine/Losartan and Rosuvastatin in Healthy Volunteers
A fixed-dose combination (FDC) tablet formulation of amlodipine/losartan/rosuvastatin 5/100/20 mg was developed to improve medication compliance in patients with both hypertension and dyslipidemia. The comparative pharmacokinetic study was performed to compare the profile of an FDC tablet formulation of amlodipine/losartan/rosuvastatin with that of concomitant administration of a currently marketed FDC tablet of amlodipine/losartan with a rosuvastatin tablet. A randomized, open-label, single oral dose, two-way crossover study was conducted in 60 healthy subjects. Subjects were orally administered the FDC tablet of amlodipine/losartan/rosuvastatin and a loose combination (LC) of two tablets comprising an FDC of amlodipine/losartan and rosuvastatin. Blood samples were collected for up to 144 h post dose for pharmacokinetic evaluations. Plasma concentrations of amlodipine, losartan, EXP3174 (an active metabolite of losartan), and rosuvastatin were measured by using liquid chromatography-tandem mass spectrometry. The geometric mean ratio (GMR) and its 90% confidence interval (90% CI) in the FDC treatment to LC treatment for the area under the concentration-time curve from zero to the last quantifiable time point (AUC ) and the maximum plasma concentration (C ) were calculated. Safety was monitored throughout the study. The GMR (90% CI) values of AUC and C were 0.9946 (0.9663-1.0238) and 0.9690 (0.9379-1.0011) for amlodipine, 0.9855 (0.9422-1.0308) and 0.9178 (0.8349-1.0089) for losartan, 0.9814 (0.9501-1.0136) and 0.9756 (0.9313-1.0219) for EXP3174, and 0.9448 (0.8995-0.9923) and 0.9609 (0.8799-1.0494) for rosuvastatin, respectively. No clinically significant changes were observed in any of the safety parameters, including clinical laboratory tests, vital signs, electrocardiograms, and physical examinations, between the FDC treatment and the LC treatment. We confirmed the pharmacokinetic equivalence of the FDC and LC treatments. This triple combination FDC formulation could be a clinically useful replacement for LC therapy.
Effect of silymarin on the pharmacokinetics of losartan and its active metabolite E-3174 in healthy Chinese volunteers
Purpose To investigate the effects of silymarin on the pharmacokinetics of losartan and its active metabolite E-3174 and its relationship with CYP2C9 genotypes. Methods Twelve healthy adult men of known CYP2C9 genotype (six CYP2C9*1/*1 and six CYP2C9*1/*3) were recruited in a two-phase randomized crossover design study. The pharmacokinetics of losartan and E-3174 were measured before and after a 14-day treatment with 140 mg of silymarin three times daily. Results The area under the plasma concentration-time curve (AUC) of losartan increased significantly following a 14-day silymarin treatment in subjects with the CYP2C9*1/*1 genotype, but not in those with the CYP2C9*1/*3 genotype. The AUC of E-3174 decreased significantly with a silymarin pretreatment in both CYP2C9*1/*1 and the CYP2C9*1/*3 subjects. The metabolic ratio of losartan (ratio of [graphic removed] of E-3174 to [graphic removed] of losartan) decreased significantly after a 14-day treatment with silymarin in individuals with the CYP2C9*1/*1 genotype (p < 0.05), but not in those with the CYP2C9*1/*3 genotype (p = 0.065). Conclusion Silymarin inhibits the metabolism of losartan to E-3174, with the magnitude of the interaction differing in individuals with different CYP2C9 genotypes.
Pharmacokinetics and bioequivalence evaluation of two losartan potassium 50-mg tablets: A single-dose, randomized-sequence, open-label, two-way crossover study in healthy Chinese male volunteers
Background: Losartan is a nonpeptide angiotensin II receptor antagonist used as an antihypertensive agent. The relative bioavailability of a newly developed tablet compared with an established branded formulation has not been reported in a Chinese population. Objective: To meet the requirements for marketing a new generic product, the study was designed to compare the pharmacokinetic parameters and relative bioavailability of a new generic losartan potassium 50-mg tablet (test formulation) with a branded 50-mg tablet (reference formulation) in healthy Chinese male volunteers. Methods: A single-dose, randomized-sequence, openlabel, 2-way crossover study was conducted in healthy Chinese male volunteers. Eligible participants were randomly assigned in a 1:1 ratio to receive a single 50-mg tablet of the test or reference formulation, followed by a 1-week washout period and then administration of the alternate formulation. The study drugs were administered after a 10-hour overnight fast. Plasma samples were collected over 36 hours. Tolerability was evaluated by recording adverse events (AEs) and monitoring vital signs, ECGs, and laboratory tests at baseline and at completion of the study. Plasma concentrations of losartan and its active metabolite (EXP3174) were analyzed by LC-MS/MS. Pharmacokinetic parameters, including C max, AUC 0–36, and AUC 0−∞, were calculated. If the 90% CIs for the log-transformed values of AUC were within 80% to 125%, and that of C max was within 70% to 143%, the 2 products would be considered bioequivalent according to the guidelines of the US Food and Drug Administration and the State Food and Drug Administration of China. Results: Twenty–seven healthy Chinese male volunteers participated in this study (mean [SD] age, 24.5 [2.3] years [range, 20–29 years]; weight, 64.6 [4.0] kg [range, 60.0-75.0 kg]; height, 172.2 [4.8] cm [range, 165.0183.0 cm]; and body mass index, 21.8 [1.2] kg/m 2 [range, 20.0–25.0 kg/m 2]). One volunteer (3.7%) experienced an AE (microscopic hematuria) after administration of the test formulation. This resolved spontaneously after 10 days and was considered by the investigator as mild; the relationship with the study drug was uncertain. No serious AEs were reported. Both formulations were associated with significant reductions in systolic and diastolic blood pressure and significant increases in heart rate compared with baseline values (all, P < 0.05). No period, formulation, or sequence effects were observed for any pharmacokinetic parameter, except for a significant subject effect. For parent losartan, the 90% CIs for the ratios (test/reference) of C max, AUC 0–36, and AUCAUC 0−∞ were 83.65% to 113.36%, 89.79% to 98.25%, and 90.95% to 99.55%, respectively. For the metabolite EXP3174, the 90% CIs for the ratios of C max, AUC 0–36, and AUCAUC 0−∞ were 93.49% to 103.61%, 96.79% to 104.09%, and 97.06% to 105.83%. Both C max and AUC met the predetermined criteria for assuming bioequivalence. The relative bioavailability of the test formulation to the reference formulation was 93.92% for losartan and 100.40% for EXP3174. Conclusions: In this small study in healthy Chinese male volunteers, a single 50-mg oral dose of a losartan potassium tablet (test formulation) met the regulatory criteria for assuming bioequivalence to the established reference formulation. Both formulations were well tolerated.
Losartan as a mechanotherapeutic adjuvant: Remodeling the breast tumor microenvironment to improve treatment efficacy
Tumor stiffness is a critical factor influencing cancer progression, therapeutic resistance, and drug delivery. This study investigates the role of mechanical normalization in breast cancer therapy through the anti-fibrotic action of losartan, an angiotensin II type 1 receptor blocker. We developed a comprehensive multiphysics model integrating tumor cell proliferation, oxygen transport, interstitial fluid dynamics, and losartan pharmacokinetics/pharmacodynamics (PK/PD). Simulations demonstrate that losartan reduces tumor stiffness by up to 28%, enhances oxygenation by 8%, and increases tumor porosity by ~45%, thereby enhancing drug penetration and interstitial transport. Furthermore, tumor cell concentration decreased by 88%, reflecting the drug’s dual anti-proliferative and pro-apoptotic effects. Spatial analyses revealed heterogeneity in stiffness reduction and drug response, emphasizing the importance of tumor geometry and perfusion. Our findings support the potential of losartan as a mechanotherapeutic adjuvant to enhance standard cancer treatments by remodeling the tumor microenvironment and overcoming mechanical barriers to therapy.
Preparation of Losartan Potassium Controlled Release Matrices and In-Vitro Investigation Using Rate Controlling Agents
Controlled release matrices have predictable drug release kinetics, provide drugs for an extended period of time, and reduce dosing frequency with improved patient compliance as compared with conventional tablet dosage forms. In the current research work, losartan potassium controlled release matrix tablets were fabricated and prepared with rate altering agents; that is, Ethocel grade 100 combined with Carbopol 934PNF. Various drug to polymer ratios were used. HPMC, CMC, and starch were incorporated in some of the matrices by replacing some amount of filler (5%). The direct compression method was adopted for the preparation of matrices. In phosphate buffer (pH 6.8), the dissolution study was conducted by adopting the USP method-I as the specified method. Drug release kinetics was determined and dissolution profiles were also compared with the reference standard. Prolonged release was observed for all matrices, but those with Ethocel 100FP Premium showed more extended release. The co-excipient (HPMC, CMC, and starch) exhibited enhancement in the drug release rates, while all controlled release matrices released the drug by anamolous non-Fickian diffusion mechanism. This combination of polymers (Ethocel grade 100 with Carbopol 934PNF) efficiently extended the drug release rates up to 24 h. It is suggested that these matrix tablets can be given in once a day dosage, which might improve patient compliance, and the polymeric blend of Ethocel grade 100 with Carbopol 934PNF might be used in the development of prolonged release matrices of other water-soluble drugs.
Losartan inhibits collagen I synthesis and improves the distribution and efficacy of nanotherapeutics in tumors
The dense collagen network in tumors significantly reduces the penetration and efficacy of nanotherapeutics. We tested whether losartan—a clinically approved angiotensin II receptor antagonist with noted antifibrotic activity—can enhance the penetration and efficacy of nanomedicine. We found that losartan inhibited collagen I production by carcinoma-associated fibroblasts isolated from breast cancer biopsies. Additionally, it led to a dose-dependent reduction in stromal collagen in desmoplastic models of human breast, pancreatic, and skin tumors in mice. Furthermore, losartan improved the distribution and therapeutic efficacy of intratumorally injected oncolytic herpes simplex viruses. Finally, it also enhanced the efficacy of i.v. injected pegylated liposomal doxorubicin (Doxil). Thus, losartan has the potential to enhance the efficacy of nanotherapeutics in patients with desmoplastic tumors.