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
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.
477 studies on the registry are indexed under Muscle Weakness; 73 are open to participants now.
This study's planned enrollment of 40 is close to the median of 44 across 362 interventional studies indexed under Muscle Weakness.
Browse Muscle Weakness studies →University of Utah is the lead sponsor of 994 studies on the registry; 175 are open to participants now.
Of its 114 completed or terminated interventional studies of FDA-regulated products, 69 (61%) have results posted.
Compared within Muscle Weakness, this study's primary condition as ClinicalTrials.gg classifies it; the registry's first condition term is Atrophy. The counts are of registry records indexed under each term, refreshed daily. How we classify →
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Individuals randomized to metformin group will take the intervention daily for 4 months after ACLR surgery
Drug: Metformin
Individuals randomized to placebo group will take the treatment daily for 4 months after ACLR surgery
Other: Placebo
Individuals randomized to the metformin group will take metformin daily (up to 2grams/day) for 4 months following ACLR surgery.
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.
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
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.
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
Plan to share: No — IPD can be requested by the PI, Dr. Micah Drummond.
No publications or documents are linked to this record.
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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Studies of the drug tested here: Metformin