Trimebutine

Trimebutine is a drug with antimuscarinic and weak mu opioid agonist effects.Trimebutine is an agonist of peripheral mu, kappa and delta opiate receptors, used as spasmolytic agent for treatment of both acute and chronic abdominal pain. The major product

A novel orally administered trimebutine compound (GIC-1001) is anti-nociceptive and features peripheral opioid agonistic activity and Hydrogen Sulphide-releasing capacity in mice.[Pubmed:26541237]

Eur J Pain. 2016 May;20(5):723-30.

BACKGROUND: Trimebutine maleate, a noncompetitive spasmolytic agent with some affinity for peripheral mu- and kappa-opioid receptors has been evaluated as a treatment in a limited number of patients undergoing sedation-free full colonoscopy. The efficiency of such treatment was comparable to sedation-based colonoscopies to relieve from pain and discomfort. METHODS: A new and improved Trimebutine salt capable of releasing in vivo hydrogen sulphide (H2S), a gaseous mediator known to reduce nociception, has been developed. This drug salt (GIC-1001) is composed of Trimebutine bearing a H2S-releasing counterion (3-thiocarbamoylbenzoate, 3TCB), the latter having the ability to release H2S. GIC-1001 has been tested here in a mouse model of colorectal distension. RESULTS: In mice, while orally given Trimebutine (the maleate salt, non-H2 S-releaser) only slightly reduced the nociceptive response to increasing pressures of colorectal distension, oral administration of GIC-1001 (the H2S-releaser) was able to significantly reduce nociceptive response to all noxious stimuli, in a dose-dependent manner. This effect of GIC-1001 was significantly better than the effects of its parent compound Trimebutine administered at equimolar doses. CONCLUSIONS: Taken together, these results demonstrated increased antinociceptive properties for GIC-1001 compared to Trimebutine, suggesting that this compound would be a better option to relieve from visceral pain and discomfort induced by lumenal distension.

An Automated Method for the Determination of Trimebutine and N-Mono-Desmethyl Trimebutine by On-Line Turbulent Flow Coupled with Liquid Chromatography-Tandem Mass Spectrometry in Human Plasma: Application to a Fatal Poisoning Case with Toxicokinetic Study.[Pubmed:26342056]

J Anal Toxicol. 2015 Nov-Dec;39(9):720-5.

A liquid chromatography-MS-MS turbulent flow on-line extraction method was developed for the determination of Trimebutine (TMB) and its main active metabolite N-mono-desmethylTrimebutine (norTrimebutine or nor-TMB) in human plasma. After protein precipitation and internal standard (IS, haloperidol-d4) addition, 50 microL of the supernatant were transferred onto a Cyclone-Turbo-Flow extraction column followed by an Hypersil PFP Gold analytical column. Detection was carried out on a triple quadrupole tandem mass spectrometer using positive electrospray ionization. The transitions used were m/z 388.0-->343.0, 374.0-->195.0 and 380.1-->169.0 for TMB, nor-TMB and IS, respectively. The method was validated over the concentration range of 10-1,000 ng/mL for both compounds. The accuracy evaluated at three concentrations was within 90.0-98.5% and the intra- and interday coefficient of variation's for the two molecules were <8.7%. The method was applied to a toxicokinetic study of a self-poisoning case with TMB in a 19-old girl. The concentration of TMB decreased from 747 to 77 ng/mL, while nor-TMB decreased from 9,745 to 205 ng/mL after 5 days and the fatal issue. This case confirms the literature underlining the potential toxicity of TMB, which has long time been considered as a harmless molecule.

Discovery of a novel trimebutine metabolite and its impact on N-desmethyltrimebutine quantification by LC-MS/MS.[Pubmed:25966011]

Bioanalysis. 2015;7(8):1007-15.

BACKGROUND: A failure in incurred sample reanalysis (ISR) for N-desmethylTrimebutine (NDMT), during the analysis of a Trimebutine-containing drug GIC-1001 Phase I study, led to the discovery of a never-before reported metabolite of Trimebutine. RESULTS: A positive bias for NDMT during the ISR and post-reconstitution stability evaluations indicated the presence of an unstable metabolite of NDMT. Precursor ion scans performed on freshly extracted samples enabled the identification of this metabolite to be the NDMT glucuronide conjugate and its fragmentation pattern suggested that the glucuronide moiety was attached at the N-terminal of NDMT. CONCLUSIONS: An acidification step was introduced in the extraction procedure to completely hydrolyze the glucuronide and measure the total NDMT in plasma, rendering this method a successful fit-for-purpose assay.