Characterization of growth hormone secretagogue small molecule ibutamoren (MK-0677) and its possible metabolites in thoroughbred horses for doping control.

Philip M, Karakka Kal AK, Subhahar MB, Karatt TK, Mathew B, Koshy SA

Rapid communications in mass spectrometry : RCM1 Sept 2022Cited by 6 (Europe PMC)

PMID35716382DOI10.1002/rcm.9337PepBankPUB-35716382

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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 study8

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

01AnimalAnimal study (in vivo)Pharmacokinetics
In thoroughbred horses, ibutamoren produced 22 identified metabolites, including 17 phase I and 5 phase II metabolites.
In plain wordsIn horses, researchers identified 22 ibutamoren metabolites.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableMetabolites identified
Study
horsen: not reported in source
thoroughbred horses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
In this study, 22 metabolites of ibutamoren were identified (17 phase I and 5 phase II).
1 context sentence(design, population, supporting numbers)
Summary · context
This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration.
Report a problemFND-3571638201
02AnimalAnimal study (in vivo)Pharmacokinetics
In thoroughbred horses, ibutamoren oxidation produced mono- and dihydroxylated metabolites.
In plain wordsIn horses, ibutamoren oxidation produced hydroxylated metabolites.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableHydroxylated metabolites
Study
horsen: not reported in source
thoroughbred horses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
Oxidation of ibutamoren leads to hydroxylated metabolites (mono and di).
1 context sentence(design, population, supporting numbers)
Summary · context
This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration.
Report a problemFND-3571638202
03AnimalAnimal study (in vivo)Pharmacokinetics
In thoroughbred horses, researchers detected dissociated benzyl and 2-amino-2-methylpropanamide side chains from ibutamoren.
In plain wordsIn horses, researchers detected detached ibutamoren side chains.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableSide-chain dissociation
Study
horsen: not reported in source
thoroughbred horses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
The study also detected dissociated side chains (benzyl group and 2-amino-2-methylpropanamide) and hydrogenated metabolites.
1 context sentence(design, population, supporting numbers)
Summary · context
This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration.
Report a problemFND-3571638203
04AnimalAnimal study (in vivo)Pharmacokinetics
In thoroughbred horses, researchers detected hydrogenated ibutamoren metabolites.
In plain wordsIn horses, researchers detected hydrogenated ibutamoren metabolites.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableHydrogenated metabolites
Study
horsen: not reported in source
thoroughbred horses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
The study also detected dissociated side chains (benzyl group and 2-amino-2-methylpropanamide) and hydrogenated metabolites.
1 context sentence(design, population, supporting numbers)
Summary · context
This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration.
Report a problemFND-3571638204
05AnimalAnimal study (in vivo)Pharmacokinetics
In thoroughbred horses, researchers detected glucuronic acid conjugated ibutamoren analogs.
In plain wordsIn horses, researchers detected ibutamoren glucuronic acid conjugates.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableGlucuronic acid conjugates
Study
horsen: not reported in source
thoroughbred horses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
The glucuronic acid conjugated analogs of ibutamoren were detected during phase II of the study, but no sulfonic acid conjugated analogs were observed.
1 context sentence(design, population, supporting numbers)
Summary · context
This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration.
Report a problemFND-3571638205
06AnimalAnimal study (in vivo)Pharmacokinetics
In thoroughbred horses, researchers observed no sulfonic acid conjugated ibutamoren analogs.
In plain wordsIn horses, researchers found no ibutamoren sulfonic acid conjugates.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableSulfonic acid conjugates
Study
horsen: not reported in source
thoroughbred horses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
The glucuronic acid conjugated analogs of ibutamoren were detected during phase II of the study, but no sulfonic acid conjugated analogs were observed.
1 context sentence(design, population, supporting numbers)
Summary · context
This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration.
Report a problemFND-3571638206
07AnimalAnimal study (in vivo)Pharmacokinetics
In thoroughbred horses, major ibutamoren metabolites remained detectable up to 96 hours after a single dose.
In plain wordsIn horses, major ibutamoren metabolites remained detectable up to 96 hours after a single dose.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableMetabolite detection window
Study
horsen: not reported in source
thoroughbred horses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
The major metabolites can be detected up to 96 hours after a single dose, and ibutamoren can persist for up to 72 hours.
1 context sentence(design, population, supporting numbers)
Summary · context
This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration.
Report a problemFND-3571638207
08AnimalAnimal study (in vivo)Pharmacokinetics
In thoroughbred horses, ibutamoren persisted for up to 72 hours.
In plain wordsIn horses, ibutamoren persisted for up to 72 hours.
Peptide
MK-677 (ibutamoren)
Outcome
Not applicableParent drug persistence
Study
horsen: not reported in source
thoroughbred horses
Outcome group
Pharmacokinetics · Pharmacology
Studied dose
Dose not stated · oralAs given in this study (horse).
Source sentences
Summary
The major metabolites can be detected up to 96 hours after a single dose, and ibutamoren can persist for up to 72 hours.
1 context sentence(design, population, supporting numbers)
Summary · context
This study examines ibutamoren and its metabolites in thoroughbred horses after oral administration.
Report a problemFND-3571638208

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

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MeSH terms

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