Pharmacokinetics, Safety, and Tolerability of Glepaglutide, a Long-Acting GLP-2 Analog, in Subjects with Renal Impairment.

BACKGROUND: Glepaglutide is a novel, ready-to-use, long-acting, glucagon-like peptide-2 (GLP-2) analog intended for the treatment of patients with short bowel syndrome (SBS). This study investigated the impact of renal function on the pharmacokinetics and safety of glepaglutide. METHODS: In this 3-site, non-randomized, open-label study, 16 subjects were enrolled: 4 with severe renal impairment (eGFR 15 to < 30 mL/min/1.73 m2), 4 with end stage renal disease (ESRD) not on dialysis (eGFR < 15 mL/min/1.73 m2), and 8 matching controls with normal renal function (eGFR ≥ 90 mL/min/1.73 m2). Blood samples were collected over a 14-day period following a single subcutaneous (SC) dose of glepaglutide 10 mg. Safety and tolerability were assessed throughout the study. The primary pharmacokinetic parameters were area under the curve between dosing and 168 h (AUC0-168 h) and the maximum plasma concentration (Cmax). RESULTS: There was no clinically relevant difference between subjects with severe renal impairment/ESRD and normal renal function with respect to total exposure (AUC0-168 h) and peak plasma concentrations (Cmax) of glepaglutide following a single SC dose. A single SC dose of glepaglutide 10 mg appeared safe and well tolerated in subjects with normal renal function and subjects with severe renal impairment or ESRD. No serious adverse events were reported, and no safety issues were identified. CONCLUSIONS: No difference in glepaglutide pharmacokinetics was seen between renal impaired and normal subjects. Based on this trial, dose adjustment appears not to be warranted in SBS patients with renal impairment. TRIAL REGISTRATION: The trial is registered at http://www. CLINICALTRIALS: gov (NCT04178447) and has the EudraCT number: 2019-001466-15.

Pharmacokinetics of Glepaglutide, A Long-Acting Glucagon-Like Peptide-2 Analogue: A Study in Healthy Subjects.

BACKGROUND AND OBJECTIVE: Glepaglutide is a novel, long-acting, glucagon-like peptide-2 analogue in a stable aqueous formulation for subcutaneous dosing to treat patients with short bowel syndrome. This study was conducted primarily to characterise the pharmacokinetics of glepaglutide in healthy subjects. METHODS: In this open-label, partially randomised, parallel-group study, healthy subjects were evenly randomised to glepaglutide 5 or 10 mg dosed subcutaneously once weekly for 6 weeks or to a single intravenous infusion of glepaglutide 1 mg. Each group comprised 15 subjects. Blood samples were drawn to determine plasma concentrations of the parent drug and its two main metabolites. Concentrations of glepaglutide were calculated as the sum of these three analytes. Citrulline was included as a pharmacodynamic biomarker. Safety was assessed throughout the study. RESULTS: From a comparison of pharmacokinetic parameters following subcutaneous versus intravenous dosing, it is concluded that the pharmacokinetics of glepaglutide following subcutaneous dosing are primarily determined by slow release of the two main glepaglutide metabolites from a subcutaneous depot. For subcutaneous dosing once weekly, the two main metabolites accounted for >98% of the overall glepaglutide exposure at steady state, with the parent drug contributing to less than 1% of exposure. The estimated mean (95% confidence interval) effective half-life for glepaglutide 5 and 10 mg was 124 (73-185) h and 88 (31-146) h, respectively. There was an increase in the citrulline concentration for both glepaglutide subcutaneous dose levels. No safety issues were identified. CONCLUSIONS: Slow release of active metabolites following subcutaneous dosing leads to a significantly protracted pharmacokinetic profile for glepaglutide. These results support that once- or twice-weekly subcutaneous dosing of glepaglutide could be an efficacious therapy for intestinal rehabilitation. GOV IDENTIFIER: NCT03279302.

Prediction of in vitro metabolic stability of calcitriol analogs by QSAR.

The metabolic stability of a drug is an important property for potential drug candidates. Measuring this property, however, can be costly and time-consuming. The use of quantitative structure-activity relationships (QSAR) to estimate the in vitro stability is an attractive alternative to experimental measurements. A data set of 130 calcitriol analogs with known values of in vitro metabolic stability was used to develop QSAR models. The analogs were encoded with molecular structure descriptors computed mainly with the commercial software QikProp and DiverseSolutions. Variable selection was carried out by five different variable selection techniques and Partial Least Squares Regression (PLS) models were generated from the 130 analogs. The models were used for prediction of the metabolic stability of 244 virtual calcitriol analogs. Twenty of the 244 analogs were selected and the in vitro metabolic stability was determined experimentally. The PLS models were able to predict the correct metabolic stability for 17 of the 20 selected analogs, corresponding to a prediction performance of 85%. The results clearly demonstrate the utility of QSAR models in predicting the in vitro metabolic stability of calcitriol analogs.

Absorption of a mutagenic metabolite released from protein-bound residues of furazolidone.

The use of nitrofurans as veterinary drugs has been banned in the EU since 1993 due to doubts on the safety of the protein-bound residues of these drugs in edible products. Following treatment of pigs with the veterinary drug furazolidone free 3-amino-2-oxazolidinone (AOZ), the side-chain of the drug, could be detected in the blood in concentrations up to 0.3 µg/ml. The identity of the free AOZ was confirmed by LC/MS. This shows that the side-chain can be released from the parent drug, most likely under the acidic conditions in the stomach. Free AOZ was also detected in the blood of rats fed pig liver with protein-bound residues of furazolidone. Incubation of isolated pig hepatocytes with radiolabeled AOZ, resulted in the formation of protein-bound metabolites, to a similar extent as observed with furazolidone itself. Much lower levels were formed in the presence of dimethylsulfoxide or 4-chlorobenzenesulfonamide, most likely due to inhibition of the enzyme involved in the metabolic activation of AOZ. These compounds also prevented the inhibition by AOZ of monoamine-oxidase (MAO) activity in pig hepatocytes. These data strongly indicate that the protein-bound metabolites of furazolidone in tissues of treated animals are derived following metabolic activation of furazolidone itself, but also of the free AOZ side-chain, following its release from the parent drug. In addition to the MAO-inhibition and formation of protein-adducts, AOZ gave a dose-related positive respons in the Salmonella/microsome mutagenicity test especially in the presence of rat liver S9-mix, in tester strains TA 1535 and TA 100. Furthermore, a positive response was obtained in the chromosome aberration test with human lymphocytes and in the bone marrow micronucleus test with mice treated intraperitoneally with AOZ. It is concluded that ingestion of protein-bound residues of furazolidone results in the release and absorption of AOZ, a compound with potential mutagenic properties. This is the first report showing that protein-bound residues of veterinary drugs can be of toxicological significance.