Renal excretion of drugs

INTRODUCTION: Active targeting of tumors by nanomaterials favors early diagnosis and the reduction of harsh side effects of chemotherapeuticals. METHOD: We synthesized magnetic nanoparticles (64 nm; -40 mV) suspended in a magnetic fluid (MF) and decorated them with anti-carcinoembryonic antigen (MFCEA; 144 nm; -39 mV). MF and MFCEA nanoparticles were successfully radiolabeled with technetium-99m (99mTc) and intravenously injected in CEA-positive 4T1 tumor-bearing mice to perform biodistribution studies...

Baxdrostat is a selective small-molecule aldosterone synthase inhibitor in development for treatment of hypertension and chronic kidney disease. This phase 1, open-label, parallel-group study assessed the safety and pharmacokinetics (PK) of baxdrostat in participants with varying degrees of renal function. Participants were enrolled into control (estimated glomerular filtration rate [eGFR] ≥60 mL/min), moderate to severe renal impairment (eGFR 15-59 mL/min), or kidney failure (eGFR <15 mL/min) groups and received a single 10-mg baxdrostat dose followed by 7 days of inpatient PK blood and urine sampling...

The renal tubular organic cation transporter 2 (OCT2) and multidrug and toxin extrusion protein 1 (MATE1) mediate the vectorial elimination of many drugs and toxins from the kidney, and endogenous biomarkers for vectorial transport (OCT2-MATE1) would allow more accurate drug dosing and help to characterize drug-drug interactions and toxicity. Human serum uptake in OCT2-overexpressing cells and metabolomics analysis were carried out. Potential biomarkers were verified in vitro and in vivo. The specificity of biomarkers was validated in renal transporter overexpressing cells and the sensitivity was investigated by Km ...

It is generally believed that bioavailability (F) calculated based on systemic concentration area under the curve (AUC) measurements cannot exceed 1.0, yet some published studies report this inconsistency. We teach and believe, based on differential equation derivations, that rate of absorption has no influence on measured systemic clearance following an oral dose, i.e., determined as available dose divided by AUC. Previously, it was thought that any difference in calculating F from urine data versus that from systemic concentration AUC data was due to the inability to accurately measure urine data...

Transplant patients face an elevated risk of coronavirus disease 2019 (COVID-19) morbidity and mortality and commonly encounter renal dysfunction. Nirmatrelvir is primarily excreted through the kidneys. The dosage of nirmatrelvir/ritonavir (NR) needs to be adjusted according to the degree of renal function impairment. Nevertheless, NR is not recommended for patients with severe renal impairment (estimated glomerular filtration rate < 30 mL/min) due to a dearth of associated research. In this study, we focus on kidney transplant patients and document and analyze the experiences of using NR in individuals with severe kidney dysfunction...

Diabetes mellitus, a widespread metabolic illness with increasing global occurrence, continues to have a significant impact on public health. Diabetes is a condition marked by long-term high blood sugar levels. It is caused by a combination of genetic, environmental, and lifestyle factors, which lead to problems with insulin production and insulin resistance. This dysfunctional state disturbs the delicate balance of glucose regulation, promoting the emergence of problems in both large and small blood vessels that have a substantial impact on illness and death rates...

Flonoltinib Maleate (FM) is a dual-target inhibitor that selectively suppresses Janus kinase 2/FMS-like tyrosine kinase 3 (JAK2/FLT3), which is currently in phase I/IIa clinical trial in China for the treatment of myeloproliferative neoplasms (MPNs). In this research, we used [14 C]-labeled FM (14 C-FM) to investigate the distribution, metabolism, and excretion of FM in rats using High-Performance Liquid Chromatography coupled with High-Resolution Mass Spectrometry/Radioactivity Monitoring (HPLC-HRMS/RAM) and liquid scintillation counter...

4-Chlorokynurenine (4-Cl-KYN, AV-101) is a prodrug of a NMDA receptor antagonist and is in clinical development for potential CNS indications. We sought to further understand the distribution and metabolism of 4-Cl-KYN, as this information might provide a strategy to enhance the clinical development of this drug. We used excretion studies in rats, in vitro transporter assays, and pharmacogenetic analysis of clinical trial data to determine how 4-Cl-KYN and metabolites are distributed. Our data indicated that a novel acetylated metabolite ( N -acetyl-4-Cl-KYN) did not affect the uptake of 4-Cl-KYN across the blood-brain barrier via LAT1...

Flavonoids have garnered attention because of their beneficial bioactivities. However, some flavonoids reportedly interact with drugs via transporters and may induce adverse drug reactions. This study investigated the effects of food ingredients on organic anion-transporting polypeptide (OATP) 4C1, which handles uremic toxins and some drugs, to understand the safety profile of food ingredients in renal drug excretion. Twenty-eight food ingredients, including flavonoids, were screened. We used ascorbic acid (AA) to prevent curcumin oxidative degradation in our method...

Purpose: The objective of this case series is to highlight different manifestations of valacyclovir associated neurotoxicity (VAN) and demonstrate the importance of adjusting medication appropriately in patients with end-stage renal disease (ESRD) on hemodialysis to prevent these complications. Summary: Valacyclovir is a medication used to treat herpes zoster infection, commonly known as shingles. Valacyclovir is renally cleared and can accumulate in patients with renal dysfunction leading to severe side effects due to the prolonged half-life...

Toxic nephropathies are a clinically common group of disorders characterized by toxin-induced renal injury that can affect the glomerulus, vasculature, or tubulointerstitium. Various endogenous (eg, myoglobin, hemoglobin, monoclonal light chains, and lysozymes) and exogenous toxins (eg, therapeutic drugs, herbal medications, heavy metals, radiocontrast, intoxicants, and environmental exposures) have been implicated. The kidney's primary role of metabolism and excretion of substances via glomerular filtration and tubular secretion increases its susceptibility to their adverse effects...

BACKGROUND: Hyperuricemia (HUA) is a disease characterized by excessive uric acid production and/or insufficient uric acid excretion caused by abnormal purine metabolism in the human body. Uric acid deposition caused by hyperuricemia can cause complications, such as kidney damage. The current therapeutic drugs for HUA are not very targeted and usually have specific toxic side effects. OBJECTIVES: This study aimed to synthesize a compound using rhein and praseodymium, which can effectively help hyperuricemia patients with kidney injury to excrete uric acid through the intestine and preliminarily explore its intestinal excretion mechanism...

BACKGROUND: The beneficial role of glucose-dependent insulinotropic polypeptide receptor (GIPR) in weight control and maintaining glucose levels has led to the development of several multi-agonistic peptide drug candidates, targeting GIPR and glucagon like peptide 1 receptor (GLP1R) and/or the glucagon receptor (GCGR). The in vivo quantification of target occupancy by these drugs would accelerate the development of new drug candidates. The aim of this study was to evaluate a novel peptide (GIP1234), based on previously reported ligand DOTA-GIP-C803, modified with a fatty acid moiety to prolong its blood circulation...

P-glycoprotein (P-gp, encoded in humans by the ABCB1 gene and in rodents by the Abcb1a/b genes) is a membrane transporter that can restrict the intestinal absorption and tissue distribution of many drugs and may also contribute to renal and hepatobiliary drug excretion. The aim of this study was to compare the performance and sensitivity of currently available radiolabeled P-gp substrates for positron emission tomography (PET) with the single-photon emission computed tomography (SPECT) radiotracer [99m Tc]Tc-sestamibi for measuring the P-gp function in the kidneys and liver...

Five siRNA-based therapeutics have been approved by the Food and Drug Administration (FDA), including patisiran, givosiran, lumasiran, inclisiran and vutrisiran. Besides, siRNA delivery to the target site without toxicity is a big challenge for researchers, and naked-siRNA delivery possesses several challenges, including membrane impermeability, enzymatic degradation, mononuclear phagocyte system (MPS) entrapment, fast renal excretion, endosomal escape, and off-target effects. The siRNA therapeutics can silence any disease-specific gene, but their intracellular and extracellular barriers limit their clinical applications...

Pritelivir is a helicase-primase inhibitor active against HSV. Two human mass balance trials (a multiple-dose trial and a single-dose trial) were performed to characterize the absorption, distribution, metabolism, and excretion of 100 mg oral pritelivir combined with a single microdose of 14 C-pritelivir. Blood, urine, and feces samples were collected up to 26 days postdose. The plasma half-life of pritelivir was 63-67 hours. Overall, 92% and 66% of the administered dose was recovered in the multiple and single dose trials, respectively...

Nirmatrelvir is a potent and selective inhibitor of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease that is used as an oral antiviral coronavirus disease 2019 (COVID-19) treatment. To sustain unbound systemic trough concentrations above the antiviral in vitro 90% effective concentration value (EC90 ), nirmatrelvir is coadministered with 100 mg of ritonavir, a pharmacokinetic enhancer. Ritonavir inhibits nirmatrelvir's cytochrome P450 (CYP) 3A4-mediated metabolism which results in renal elimination becoming the primary route of nirmatrelvir elimination when dosed concomitantly...

The field of RNA therapeutics has been emerging as the third milestone in pharmaceutical drug development. RNA nanoparticles have displayed motile and deformable properties to allow for high tumor accumulation with undetectable healthy organ accumulation. Therefore, RNA nanoparticles have the potential to serve as potent drug delivery vehicles with strong anti-cancer responses. Herein, we report the physicochemical basis for the rational design of a branched RNA four-way junction (4WJ) nanoparticle that results in advantageous high-thermostability and -drug payload for cancer therapy, including metastatic tumors in the lung...

BACKGROUND: Diabetic nephropathy is a clinical syndrome characterized by persistent albuminuria and progressive impairment in renal function. Pentoxifylline is a non-specific inhibitor of phosphodiesterase with anti-inflammatory properties which may have therapeutic potency in patients with diabetic kidney disease. OBJECTIVE: The present study is aimed at evaluating the efficacy of pentoxifylline as a treatment strategy for alleviating the microalbuminuria in type-2 diabetic patients with nephropathy...

OBJECTIVE: The aim of the study was to determine the pharmacokinetics (PK) and safety of single and repeat doses of intravenous (IV) N-acetylcysteine (NAC) in Chinese subjects. PATIENTS AND METHODS: A total of 24 healthy male and female Chinese subjects aged 19-40 years were enrolled in this open-label phase I study. All subjects received a single dose of NAC 600 mg IV on day 1 and, after a 3-day washout, received repeat doses of NAC 600 mg IV (twice daily on days 4 and 5 and once on day 6)...