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Study · Randomized controlled trial · 2025

6 results

Tirzepatide did not impact metabolic adaptation in people with obesity, but increased fat oxidation.

Ravussin E, Sanchez-Delgado G, Martin CK, Beyl RA, Greenway FL, O'Farrell LS, Roell WC, Qian HR, Li J, Nishiyama H, Haupt A, Pratt EJ, Urva S, Milicevic Z, Coskun T

Cell metabolism8 Apr 2025Cited by 45 (Europe PMC)

PMID40203836 (opens in a new tab)DOI10.1016/j.cmet.2025.03.011 (opens in a new tab)PepBankPUB-40203836
Publisher pagePubMedAsk about this study
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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 study6

6 results from studies that gave the peptide. 4 results from people.

  1. 01HumanRandomized controlled trialMechanism

    In people with obesity in a phase 1 trial, tirzepatide appeared to have no impact on metabolic adaptation versus placebo.

    In plain wordsIn people with obesity, tirzepatide appeared to have no effect on metabolic adaptation compared with placebo.

    Peptide
    Tirzepatide
    Outcome
    No significant changeMetabolic adaptation
    Study

    n: not reported in source

    Comparator
    Placebo
    Outcome group
    Body weight · Metabolic and weight
    Studied dose
    Dose not stated

    Source sentences

    Summary
    tirzepatide appeared to have no impact on metabolic adaptation but led to increased fat oxidation and reductions in appetite and calorie intake during an ad libitum test meal (vs. placebo).
    1 context sentence
    Summary · context
    We conducted a preclinical study and a phase 1 clinical trial (NCT04081337) to understand potential mechanisms mediating tirzepatide-induced weight loss in mice and people with obesity.
  2. 02HumanRandomized controlled trialMechanism

    In people with obesity in a phase 1 trial, tirzepatide increased fat oxidation versus placebo.

    In plain wordsIn people with obesity, tirzepatide increased fat burning compared with placebo.

    Peptide
    Tirzepatide
    Outcome
    IncreaseFat oxidation
    Study

    n: not reported in source

    Comparator
    Placebo
    Outcome group
    Body weight · Metabolic and weight
    Studied dose
    Dose not stated

    Source sentences

    Summary
    tirzepatide appeared to have no impact on metabolic adaptation but led to increased fat oxidation and reductions in appetite and calorie intake
    1 context sentence
    Summary · context
    We conducted a preclinical study and a phase 1 clinical trial (NCT04081337) to understand potential mechanisms mediating tirzepatide-induced weight loss in mice and people with obesity.
  3. 03HumanRandomized controlled trialEfficacy outcome

    In people with obesity in a phase 1 trial, tirzepatide reduced appetite versus placebo.

    In plain wordsIn people with obesity, tirzepatide reduced appetite compared with placebo.

    Peptide
    Tirzepatide
    Outcome
    DecreaseAppetite during an ad libitum test meal
    Study

    n: not reported in source

    Comparator
    Placebo
    Outcome group
    Appetite and food intake · Metabolic and weight
    Studied dose
    Dose not stated

    Source sentences

    Summary
    tirzepatide appeared to have no impact on metabolic adaptation but led to increased fat oxidation and reductions in appetite and calorie intake during an ad libitum test meal (vs. placebo)
    1 context sentence
    Summary · context
    We conducted a preclinical study and a phase 1 clinical trial (NCT04081337) to understand potential mechanisms mediating tirzepatide-induced weight loss in mice and people with obesity.
  4. 04HumanRandomized controlled trialEfficacy outcome

    In people with obesity in a phase 1 trial, tirzepatide reduced calorie intake at an ad libitum test meal versus placebo.

    In plain wordsIn people with obesity, tirzepatide reduced calorie intake at a test meal compared with placebo.

    Peptide
    Tirzepatide
    Outcome
    DecreaseCalorie intake during an ad libitum test meal
    Study

    n: not reported in source

    Comparator
    Placebo
    Outcome group
    Appetite and food intake · Metabolic and weight
    Studied dose
    Dose not stated

    Source sentences

    Summary
    tirzepatide appeared to have no impact on metabolic adaptation but led to increased fat oxidation and reductions in appetite and calorie intake during an ad libitum test meal (vs. placebo)
    1 context sentence
    Summary · context
    We conducted a preclinical study and a phase 1 clinical trial (NCT04081337) to understand potential mechanisms mediating tirzepatide-induced weight loss in mice and people with obesity.
  5. 05AnimalAnimal study (in vivo)Mechanism

    In calorie-restricted obese mice, chronic tirzepatide reduced the drop in energy expenditure seen in vehicle-treated and pair-fed mice, which indicates attenuated metabolic adaptation.

    In plain wordsIn mice, tirzepatide reduced the fall in energy use that happens with calorie restriction, compared with vehicle and pair-fed mice.

    Peptide
    Tirzepatide
    Outcome
    IncreaseEnergy expenditure drop during calorie restriction
    Study

    mousen: not reported in source

    calorie-restricted obese mice
    Comparator
    Vehicle-treated and pair-fed mice
    Outcome group
    Body weight · Metabolic and weight
    Studied dose
    Dose not stated

    Source sentences

    Summary
    In calorie-restricted, obese mice, chronic treatment with tirzepatide reduced the drop in energy expenditure that occurred in vehicle-treated and pair-fed mice, indicating that tirzepatide attenuated metabolic adaptation.
    1 context sentence
    Summary · context
    We conducted a preclinical study and a phase 1 clinical trial (NCT04081337) to understand potential mechanisms mediating tirzepatide-induced weight loss in mice and people with obesity.
  6. 06AnimalAnimal study (in vivo)Mechanism

    In calorie-restricted obese mice, tirzepatide decreased the respiratory exchange ratio, which indicates increased fat oxidation.

    In plain wordsIn mice, tirzepatide lowered the respiratory exchange ratio, a sign that the animals burned more fat.

    Peptide
    Tirzepatide
    Outcome
    DecreaseRespiratory exchange ratio
    Study

    mousen: not reported in source

    calorie-restricted obese mice
    Comparator
    Vehicle-treated and pair-fed mice
    Outcome group
    Body weight · Metabolic and weight
    Studied dose
    Dose not stated

    Source sentences

    Summary
    Respiratory exchange ratio also decreased in tirzepatide-treated mice, indicating increased fat oxidation.
    1 context sentence
    Summary · context
    We conducted a preclinical study and a phase 1 clinical trial (NCT04081337) to understand potential mechanisms mediating tirzepatide-induced weight loss in mice and people with obesity.

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.

  1. Version 2Current

    12 Oct 2026, 12:58 UTC

    Study results updated

  2. Version 1

    9 Oct 2026, 03:07 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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