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Not yet recruitingNCT07699367Updated Jul 13, 2026

Metformin and ACLR Muscle Recovery

An Early Phase 1 interventional study of Metformin and Placebo in Atrophy, Inflammation and Weakness, Muscle, sponsored by University of Utah. Not yet recruiting at 1 site in United States. Open to participants aged 40 Years and older. Per ClinicalTrials.gov, last updated 2026-07-13.

Sponsored by University of Utah · Early Phase 1, Interventional, and Basic science

Phase
Early Phase 1
Study type
Interventional
Enrollment
40
Allocation
Randomized
Ages
40 Years and older
Sex
All
01

Study summary

The purpose of this research study is to determine if Metformin taken after anterior cruciate ligament reconstruction (ACLR) surgery can decrease muscle fibrosis, cellular senescence and improve leg strength. ACL injury and surgery increase muscle collagen content and inflammation which slows the recovery of muscle and function and ultimately impacts the quality of life. Individuals enrolled in the study will be randomized to receive metformin (or placebo) for 4 months after surgery. The investigators will measure muscle strength and inflammatory markers in muscle biopsy samples after the intervention period. Investigators will also follow up with participants 8 months later to determine the lasting effects of the intervention.

02

Conditions studied

  • Atrophy
  • Inflammation
  • Weakness, Muscle
03

Who can participate

Ages eligible
40 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Inclusion criteria

  1. Age between 40y and older
  2. BMI: \<30 kg/m2
  3. Full thickness ACL tear
  4. Less than 6 months between ACL injury and scheduled ACLR

Exclusion criteria

Exclusion Criteria:

  1. Prior ACL tear in limb scheduled for reconstruction or current bilateral ACL tear
  2. Total knee dislocation
  3. Anticipated quadriceps ACLR grafts
  4. Current infection near the lower limb
  5. Inability to attend physical therapy sessions
  6. Post-operative loading restrictions
  7. History of cardiovascular disease (e.g., CHF, CAD, MI, CVA)
  8. History of endocrine or metabolic disease such as hypo/hyperthyroidism and diabetes (Treated hypo/hyperthyroid for at least 6 months will be permitted)
  9. History of stroke with motor disability
  10. History of respiratory disease (acute upper respiratory infection, history of chronic lung disease)
  11. Self-reported pregnancy
  12. Bleeding disorder
  13. Implanted electronic devices (e.g., pacemakers, electronic infusion pumps, stimulators)
  14. Cancer or history of successfully treated cancer (less than 1 year) other than basal cell carcinoma
  15. Chronic systemic corticosteroid use (≥ 2 weeks) within 4 weeks of enrollment and for study duration (intra-articular/topical/inhaled therapeutic or physiologic doses of corticosteroids will be permitted)
  16. Androgens or growth hormone within 6 months of enrollment and for study duration (topical physiologic androgen replacement will be permitted)
  17. Currently taking estrogen products (topical estrogen products will be permitted)
  18. Taking anticoagulant medication (warfarin/Coumadin, heparin) that may complicate the muscle biopsy
  19. Any staff members who report directly to the principal investigators
04

Study design

Phase
Early Phase 1
Primary purpose
Basic science
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Triple (Participant, Investigator, Outcomes assessor)
Enrollment
40 participants (estimated)

Study arms

  • Experimental
    Metformin

    Individuals randomized to metformin group will take the intervention daily for 4 months after ACLR surgery

    Drug: Metformin

  • Placebo comparator
    Placebo

    Individuals randomized to placebo group will take the treatment daily for 4 months after ACLR surgery

    Other: Placebo

Interventions

  • DrugMetformin

    Individuals randomized to the metformin group will take metformin daily (up to 2grams/day) for 4 months following ACLR surgery.

  • OtherPlacebo

    Individuals randomized to the placebo will take the same number of pills as the metformin group daily over a 4 month period following ACLR surgery.

05

What researchers measure

Primary outcomes

  1. Thigh Muscle Fibrosis

    Muscle collagen content (% Sirius Red Stain) will be measured in muscle biopsy samples from the involved thigh after 4 months of treatment and compared between the metformin and placebo groups.

    Time frame: Measured at 4 months after ACLR surgery

  2. Thigh Muscle Cellular Senescence

    Muscle cellular senescence (% SA Beta galactosidase) will be measured in muscle biopsy samples from the involved thigh after 4 months treatment and will be compared between the metformin and placebo groups

    Time frame: Measured at 4 months following ACLR surgery.

  3. Knee extensor muscle strength

    Knee extensor muscle strength from the involved leg (maximal voluntary isometric contraction; force) will be measured using an isokinetic dynamometer after 4 months of treatment and compared between the metformin and placebo groups.

    Time frame: Measured at 4 months following ACLR surgery

06

Study locations

1 site
  • University of Utah
    Salt Lake City, Utah 84112, United States
07

References and documents

Individual participant data

Plan to share: No — IPD can be requested by the PI, Dr. Micah Drummond.

No publications or documents are linked to this record.

08

Registry details

Key details

Study ID
NCT07699367
Lead sponsor
University of Utah
Responsible party
Micah Drummond (Professor, University of Utah) — Principal investigator
First posted
Jul 13, 2026
Start date
Nov 1, 2026 (estimated)
Primary completion
Oct 1, 2031 (estimated)
Completion
Oct 1, 2032 (estimated)
Last update
Jul 13, 2026

Study contacts

Micah Drummond
Contact
micah.drummond@hsc.utah.edu
801-213-2737
Micah Drummond
principal investigator · University of Utah

Oversight

Data monitoring committee
No
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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This study is not yet recruiting, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.

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