XP13512 [(+/-)-1-([(alpha-isobutanoyloxyethoxy)carbonyl] aminomethyl)-1-cyclohexane acetic acid], a novel gabapentin prodrug: I. Design, synthesis, enzymatic conversion to gabapentin, and transport by intestinal solute transporters.

Article Details

Citation

Cundy KC, Branch R, Chernov-Rogan T, Dias T, Estrada T, Hold K, Koller K, Liu X, Mann A, Panuwat M, Raillard SP, Upadhyay S, Wu QQ, Xiang JN, Yan H, Zerangue N, Zhou CX, Barrett RW, Gallop MA

XP13512 [(+/-)-1-([(alpha-isobutanoyloxyethoxy)carbonyl] aminomethyl)-1-cyclohexane acetic acid], a novel gabapentin prodrug: I. Design, synthesis, enzymatic conversion to gabapentin, and transport by intestinal solute transporters.

J Pharmacol Exp Ther. 2004 Oct;311(1):315-23. Epub 2004 May 14.

PubMed ID
15146028 [ View in PubMed
]
Abstract

Gabapentin is thought to be absorbed from the intestine of humans and animals by a low-capacity solute transporter localized in the upper small intestine. Saturation of this transporter at doses used clinically leads to dose-dependent pharmacokinetics and high interpatient variability, potentially resulting in suboptimal drug exposure in some patients. XP13512 [(+/-)-1-([(alpha-isobutanoyloxyethoxy)carbonyl] aminomethyl)-1-cyclohexane acetic acid] is a novel prodrug of gabapentin designed to be absorbed throughout the intestine by high-capacity nutrient transporters. XP13512 was stable at physiological pH but rapidly converted to gabapentin in intestinal and liver tissue from rats, dogs, monkeys, and humans. XP13512 was not a substrate or inhibitor of major cytochrome P450 isoforms in transfected baculosomes or liver homogenates. The separated isomers of XP13512 showed similar cleavage in human tissues. The prodrug demonstrated active apical to basolateral transport across Caco-2 cell monolayers and pH-dependent passive permeability across artificial membranes. XP13512 inhibited uptake of (14)C-lactate by human embryonic kidney cells expressing monocarboxylate transporter type-1, and direct uptake of prodrug by these cells was confirmed using liquid chromatography-tandem mass spectrometry. XP13512 inhibited uptake of (3)H-biotin into Chinese hamster ovary cells overexpressing human sodium-dependent multivitamin transporter (SMVT). Specific transport by SMVT was confirmed by oocyte electrophysiology studies and direct uptake studies in human embryonic kidney cells after tetracycline-induced expression of SMVT. XP13512 is therefore a substrate for several high-capacity absorption pathways present throughout the intestine. Therefore, administration of the prodrug should result in improved gabapentin bioavailability, dose proportionality, and colonic absorption compared with administration of gabapentin.

DrugBank Data that Cites this Article

Drugs
Drug Transporters
DrugTransporterKindOrganismPharmacological ActionActions
Gabapentin enacarbilSodium-coupled monocarboxylate transporter 1ProteinHumans
No
Substrate
Details
Gabapentin enacarbilSodium-dependent multivitamin transporterProteinHumans
No
Substrate
Details