Pharmacokinetics, Metabolism, and Excretion of Intravenous [14C]Difelikefalin in Healthy Subjects and Subjects on Hemodialysis.

Bibliographic Details
Title: Pharmacokinetics, Metabolism, and Excretion of Intravenous [14C]Difelikefalin in Healthy Subjects and Subjects on Hemodialysis.
Authors: Stark, Jeffrey G., Noonan, Patrick K., Spencer, Robert H., Bhaduri, Sarbani, O'Connor, Stephen J., Menzaghi, Frédérique
Source: Clinical Pharmacokinetics; Sep2023, Vol. 62 Issue 9, p1231-1241, 11p
Subject Terms: ITCHING, EXCRETION, KIDNEY physiology, METABOLISM, CHRONIC kidney failure, PHARMACOKINETICS
Abstract: Background and Objective: Difelikefalin, a selective kappa-opioid receptor agonist, is the first approved treatment for moderate-to-severe pruritus in patients with end-stage renal disease (ESRD) on hemodialysis (HD) in the USA and Europe. The purpose of this open-label study was to investigate the pharmacokinetics and disposition of [14C]difelikefalin following a single intravenous dose in subjects with normal renal function and subjects on HD. Methods: Twelve adult males (n = 6 healthy subjects; n = 6 subjects on HD) received single intravenous doses of [14C]difelikefalin containing 100 µCi (total doses of 1.7–3.0 μg/kg difelikefalin). Blood, urine, feces, and dialysate samples (when applicable) were collected after dosing. Results: The median time to maximum concentration was similar for HD and healthy subjects, occurring at 5 min post-dose. The mean area under the concentration–time curve (AUC) was approximately 11-fold higher in HD versus healthy subjects; mean plasma half-life was 38.0 h and 2.6 h, respectively. In healthy subjects, 80.5% of the dose was recovered in urine, and 11.3% was recovered in feces. In subjects on HD, 58.8% of the dose was recovered in feces, and 19.5% was recovered in dialysate [for subjects on HD with residual kidney function (n = 3), 11.2% was recovered in urine]. Based on plasma AUClast, parent [14C]difelikefalin was the most abundant analyte in systemic circulation (> 99% of total exposure) for both cohorts. Metabolite profiles in urine and feces suggested minimal metabolism of the parent compound. Conclusion: In subjects on HD, difelikefalin total exposure was higher and plasma half-life was longer compared with subjects with intact renal function. Metabolism was low in both healthy subjects and subjects on HD, with unchanged drug representing > 99% of systemic circulation; however, the route of excretion was primarily into urine versus feces in healthy subjects, and feces versus dialysate in subjects on HD. Registration: ClinicalTrials.gov NCT03947970. [ABSTRACT FROM AUTHOR]
Copyright of Clinical Pharmacokinetics is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Complementary Index
More Details
ISSN:03125963
DOI:10.1007/s40262-023-01262-2
Published in:Clinical Pharmacokinetics
Language:English