A Phase 2 interventional study of Alpha-lipoic acid and Mirabegron in Insulin Resistance and Obesity, sponsored by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Not yet recruiting at 1 site in United States. Open to participants aged 18 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-10.
Sponsored by National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) · Phase 2, Interventional, and Treatment
Background:
Obesity and related illnesses cause at least 2.8 million deaths each year worldwide. Few treatments exist for obesity that are safe and widely available. A study drug (mirabegron [MG]) combined with a supplement (alpha-lipoic acid [ALA]) may help.
Objective:
To learn how MG and ALA can help the body process food.
Eligibility:
People aged 18 to 65 years with a body mass index between 30 and 45 kg/m2.
Design:
Participants will be screened. They will have a physical exam. They will have blood and urine tests and a test of their heart function. They will speak with a dietician.
The study has two phases. Each phase begins with a 2-day stay in the clinic; then the participant will take the study drugs at home for about 4 weeks, followed by another 2-day stay in the clinic. They will also have outpatient visits about 2 weeks after each clinic stay.
During the clinic stays, participants will undergo many tests:
They will have a plastic tube (catheter) inserted into a vein in each arm. These will be used to draw blood and to infuse glucose (sugar) and insulin.
They will have imaging scans.
They will have a clear hard plastic shield placed over their head to measure oxygen and carbon dioxide as they breathe.
Participants will take the study drugs at home. Both MG and ALA are taken by mouth with water. During one phase, participants will take MG plus a placebo. A placebo looks like the study drug but doesn t contain medicine....
Study Description:
This is a single site, Phase II single-blinded, randomized placebo control crossover pilot study. This study aims to explore the effect of adding alphalipoic acid (ALA) to mirabegron (MG) on glucose metabolism and lipolysis rate. Participant target enrollment of 48 total otherwise healthy women (n=24) and men (n=24) with obesity who will be given one of two dosing assignments: MG 50 mg/d and ALA 2400 mg/d or MG 50 mg/d + placebo over 4 weeks followed by a 4-26-week washout period, after which time participant cross over to the opposite dosing assignment. Participants will undergo metabolic testing, safety assessments, and imaging before and after each of the two arms are completed. Women and men will be studied separately using the same protocol.
We hypothesize that in women and in men with obesity (BMI 30-45 kg/m\^2), the increases in insulin sensitivity and beta3-AR agonist-induced lipolysis before and after four weeks of taking the dosing assignment will be higher in participants taking the combination MG 50 mg/d and ALA 2400 mg/d compared to taking MG 50 mg/d +placebo.
-Of note, based on our preliminary data and reports in the literature, a key secondary hypothesis is that in women and in men with obesity (BMI 30-45 kg/m\^2), the increases in beta3-AR agonist-induced lipolysis before and after four weeks of dosing will be higher in participants taking the combination MG 50 mg/d and ALA 2400 mg/d compared to taking MG 50 mg/d + placebo.
Objectives:
Secondary objectives:
Endpoints:
Secondary Endpoints:
Tertiary/Exploratory Endpoints:
2,969 studies on the registry are indexed under Insulin Resistance; 338 are open to participants now.
This study's planned enrollment of 60 is above the median of 40 across 2,369 interventional studies indexed under Insulin Resistance.
Browse Insulin Resistance studies →National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) is the lead sponsor of 538 studies on the registry; 55 are open to participants now.
Of its 80 completed or terminated interventional studies of FDA-regulated products, 51 (64%) have results posted.
Counted across the registry records on this site, refreshed daily.
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.
To be eligible to participate in this study, an individual must meet all of the following criteria:
EXCLUSION CRITERIA
An individual who meets any of the following criteria will be excluded from participation in this study:
Current use of any drugs known to:
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.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
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.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECG (electrocardiogram)
A recording of the heart’s electrical activity, taken with stickers on the chest, arms and legs. It takes a few minutes and does not hurt.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
QT and QTc
On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.
The study may name a correction formula and a limit in milliseconds, often around 450–480.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Child-Pugh class
A score of how well the liver works in people with liver disease such as cirrhosis: class A is mild, B moderate and C severe.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ALT and AST (liver enzymes)
Two enzymes measured in a routine blood test of the liver. Higher levels can mean the liver is under strain or damaged. SGPT and SGOT are older names for ALT and AST.
Criteria usually give a limit as a multiple of the upper limit of normal (ULN), often higher when cancer has spread to the liver.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants receive 50mg/day MG and 2.4g/day ALA (taken in two doses, once in the morning and once in the evening). Then, after a 4-26 week washout period, participants receive 50mg/day MG and twice a day (morning and evening) placebo.
Drug: Alpha-lipoic acid · Drug: Mirabegron · Drug: Placebo
Participants receive 50mg/day MG and twice a day (morning and evening) placebo. Then, after a 4-26 week washout period, participants receive 50mg/day MG and 2.4g/day ALA (taken in two doses, once in the morning and once in the evening).
Drug: Alpha-lipoic acid · Drug: Mirabegron · Drug: Placebo
ALA (2.4g) is in a capsule taken twice per day, once in the morning and once in the evening.
Mirabegron (50mg) is a yellow pill taken once per day in the morning.
Placebo will be visibly similar to ALA capsules. They are off-white, clear vegetable-based capsules containing an inert microcrystalline cellulose powder.
Changes in the Insulin sensitivity index (SI) obtained from FSIGT, in (mU/L)^-1 * min^-1
Change in the Insulin sensitivity index before and after 4 weeks of MG and ALA minus change in the insulin sensitivity index before and after 4 weeks of MG and placebo. This measures a change in insulin sensitivity index following ALA while controlling for changes in insulin sensitivity index due to placebo.Delta SI = (SI after ALA - SI before ALA)- (SI after placebo - SI before placebo)
Time frame: Insulin sensitivity index measured before and after each intervention in sequence
Maximum observed plasma concentration of ALA (Cmax)
Maximum observed plasma concentration of ALA in ug/mL, measured in serial blood sampling conducted in first 6 hours following MG+ALA dose at study visit
Time frame: 0-6 hours after dose of MG+ALA
Time to maximum observed plasma concentration of ALA (Tmax)
Tmax of ALA in minutes, measured in serial blood sampling conducted in first 6 hours following MG+ALA dose at study visit
Time frame: 0-6 hours after dose of MG+ALA
Area under the concentration-time curve for ALA
AUC calculated by measuring ALA concentrations in serial blood samples taken in first 6 hours following MG+ALA dose at study visit
Time frame: 0-6 hours after dose of MG+ALA
Changes in adipose tissue local inflammation in adipose tissue biopsy samples
Calculated as number of macrophages per high-power fieldChange in inflammation = (macrophages after ALA - macrophages before ALA) - (macrophages after placebo - macrophages before placebo)
Time frame: Measured before and after each intervention in sequence
Changes in serum cytokines
Measured in ug/mL of serumChange in cytokines = (cytokine concentration after ALA - cytokine concentration before ALA) - (cytokine concentration after placebo - cytokine concentration before placebo)
Time frame: Measured before and after each intervention in sequence
Changes in plasma lipids
Measured in uMol of lipids in plasma samplesChange in lipids = (lipid concentration after ALA - lipid concentration before ALA) - (lipid concentration after placebo - lipid concentration before placebo)
Time frame: Measured before and after each intervention in sequence
Changes in the rate of steady-state whole-body lipolysis
Measured as the rate of isotope appearance (Ra) of \[2H5\] glycerol in plasma, with units of mg/kg/minChange in Ra = (Ra after ALA - Ra before ALA) - (Ra after placebo - Ra before placebo)
Time frame: Measured before and after each intervention in sequence
Plan to share: Undecided
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drugs tested here: Thioctic Acid · Mirabegron
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