Equine metabolism of the growth hormone secretagogue MK-0677 in vitro and in urine and plasma following oral administration.

Cutler C, Viljanto M, Taylor P, Habershon-Butcher J, Van Eenoo P

Drug testing and analysis25 Mar 2022Cited by 2 (Europe PMC)

PMID35302297DOI10.1002/dta.3252PepBankPUB-35302297

Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study7

7 results from studies that gave the peptide. No result from this study comes from people.

01AnimalAnimal study (in vivo)Pharmacokinetics
After MK0677 administration to horses, urine contained 13 phase I metabolites alongside the parent compound.
In plain wordsIn horses, urine contained 13 MK0677 metabolites and the original compound after dosing.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableUrinary metabolites
Study
horsen = 2
Thoroughbred racehorses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
Fourteen phase I metabolites were identified in vitro; 13 of these were subsequently detected in urine and nine in plasma collected post-administration, alongside the parent compound in both matrices.
1 context sentence(design, population, supporting numbers)
Summary · context
The aim of this study was to investigate the metabolism of MK0677 in the horse following in vitro incubation and oral administration to two Thoroughbred racehorses
Report a problemFND-3530229702
02AnimalAnimal study (in vivo)Pharmacokinetics
After MK0677 administration to horses, plasma contained nine phase I metabolites alongside the parent compound.
In plain wordsIn horses, plasma contained nine MK0677 metabolites and the original compound after dosing.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicablePlasma metabolites
Study
horsen = 2
Thoroughbred racehorses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
Fourteen phase I metabolites were identified in vitro; 13 of these were subsequently detected in urine and nine in plasma collected post-administration, alongside the parent compound in both matrices.
1 context sentence(design, population, supporting numbers)
Summary · context
The aim of this study was to investigate the metabolism of MK0677 in the horse following in vitro incubation and oral administration to two Thoroughbred racehorses
Report a problemFND-3530229703
03AnimalAnimal study (in vivo)Pharmacokinetics
In horse urine, an O-dealkylated MK-0677 metabolite had the longest detection duration among detected analytes.
In plain wordsIn horses, an O-dealkylated MK-0677 metabolite remained detectable in urine longer than other detected analytes.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableUrine detection duration
Study
horsen = 2
Thoroughbred racehorses
Comparator
other detected analytes
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
In both urine and plasma, the longest duration of detection was observed for an O-dealkylated metabolite of MK-0677, and therefore, this would be the best target for the detection of MK-0677 administration.
1 context sentence(design, population, supporting numbers)
Summary · context
The aim of this study was to investigate the metabolism of MK0677 in the horse following in vitro incubation and oral administration to two Thoroughbred racehorses
Report a problemFND-3530229704
04AnimalAnimal study (in vivo)Pharmacokinetics
In horse plasma, an O-dealkylated MK-0677 metabolite had the longest detection duration among detected analytes.
In plain wordsIn horses, an O-dealkylated MK-0677 metabolite remained detectable in plasma longer than other detected analytes.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicablePlasma detection duration
Study
horsen = 2
Thoroughbred racehorses
Comparator
other detected analytes
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
In both urine and plasma, the longest duration of detection was observed for an O-dealkylated metabolite of MK-0677, and therefore, this would be the best target for the detection of MK-0677 administration.
1 context sentence(design, population, supporting numbers)
Summary · context
The aim of this study was to investigate the metabolism of MK0677 in the horse following in vitro incubation and oral administration to two Thoroughbred racehorses
Report a problemFND-3530229705
05AnimalAnimal study (in vivo)Pharmacokinetics
In horses, MK-0677 and its O-dealkylated metabolite were excreted largely unconjugated in urine.
In plain wordsIn horses, MK-0677 and its O-dealkylated metabolite appeared mainly unconjugated in urine.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableUnconjugated urinary excretion
Study
horsen = 2
Thoroughbred racehorses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
MK-0677 and the O-dealkylated metabolite were found to be excreted largely unconjugated in urine and plasma.
1 context sentence(design, population, supporting numbers)
Summary · context
The aim of this study was to investigate the metabolism of MK0677 in the horse following in vitro incubation and oral administration to two Thoroughbred racehorses
Report a problemFND-3530229706
06AnimalAnimal study (in vivo)Pharmacokinetics
In horses, MK-0677 and its O-dealkylated metabolite were reported largely unconjugated in plasma.
In plain wordsIn horses, MK-0677 and its O-dealkylated metabolite appeared mainly unconjugated in plasma.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableUnconjugated plasma profile
Study
horsen = 2
Thoroughbred racehorses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
MK-0677 and the O-dealkylated metabolite were found to be excreted largely unconjugated in urine and plasma.
1 context sentence(design, population, supporting numbers)
Summary · context
The aim of this study was to investigate the metabolism of MK0677 in the horse following in vitro incubation and oral administration to two Thoroughbred racehorses
Report a problemFND-3530229707
07LabIn vitro (cell-free)Pharmacokinetics
In vitro equine metabolism experiments identified fourteen phase I metabolites of MK0677.
In plain wordsIn lab tests, MK0677 produced fourteen phase I metabolites in an equine metabolism system.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableIn vitro metabolites
Study
horsen: not reported in source
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated
Source sentences
Summary
Fourteen phase I metabolites were identified in vitro;
1 context sentence(design, population, supporting numbers)
Summary · context
The aim of this study was to investigate the metabolism of MK0677 in the horse following in vitro incubation and oral administration to two Thoroughbred racehorses
Report a problemFND-3530229701

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
14 Oct 2026, 05:02 UTC
Study results updated
Version 1
14 Oct 2026, 01:46 UTC
First added · source update from Europe PMC

Subjects

Terms as the source lists them.

Publication types

Journal Article

MeSH terms

Keywords

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