NCT07055282 · University of Chicago
SGLT2i in Kidney Stones
What this study is about
This study is looking at whether empagliflozin, a medication typically used for diabetes and heart conditions, may affect factors that contribute to kidney stone formation. The research focuses on people who have had calcium-based kidney stones, i.e. calcium oxalate or calcium phosphate stones.
View original scientific description
This study is looking at whether empagliflozin, a medication typically used for diabetes and heart conditions, may affect factors that contribute to kidney stone formation. The research focuses on people who have had calcium-based kidney stones, i.e. calcium oxalate or calcium phosphate stones. Previous studies in those without kidney stones found that empagliflozin increased urinary citrate levels without raising urine pH. The investigators are testing whether similar effects occur in people with a history of kidney stones. Participants will take empagliflozin daily for 4 weeks. The investigators will collect 24-hour urine samples before and after treatment to measure various factors that influence stone formation, including citrate levels, pH, and calculated stone formation risk. The investigators will enroll 32 participants: 16 with a history of calcium oxalate stones and 16 with calcium phosphate stones. Results from this study may inform future larger clinical trials investigating empagliflozin as a kidney stone prevention strategy.
Interventions
DRUG
Empagliflozin (Jardiance®)
Empagliflozin (Jardiance®), 10 mg tablet taken orally once daily for 4 weeks. Dispensed at baseline by the Investigational Drug Service. It will be administered at home by participants.
Primary outcome measures
Change in calcium phosphate
Time frame: 4 weeks
Calcium phosphate supersaturation will be measured or calculated at baseline and study completion. The investigators will calculate change in calcium phosphate supersaturation for all participants and within each group.
Change in urine citrate
Time frame: 4 weeks
Urine citrate will be measured or calculated at baseline and study completion. The investigators will calculate change in urine citrate for all participants and within each group.
Change in pH
Time frame: 4 weeks
pH will be measured or calculated at baseline and study completion. The investigators will calculate change in pH for all participants and within each group.
Calcium oxalate supersaturation
Time frame: 4 weeks
Calcium oxalate supersaturation will be measured or calculated at baseline and study completion. The investigators will calculate change in calcium oxalate supersaturation for all participants and within each group.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Calcium phosphate (CaP) stone participants:
- History of at least one calcium phosphate (hydroxyapatite) stone
- Defined as at least 50% of stone material on most recent stone analysis Calcium oxalate (CaOx) stone participants:
- History of at least one calcium oxalate stone
- Defined as at least 50% of stone material on most recent stone analysis. Other inclusion criteria considerations: The investigators will study balanced numbers of male and females. Prior studies did not have balanced representation of male and female sexes. In prior studies, less than 40% were female, or sex data is not presented. Study of both male and female sex is crucial with kidney stones and therapies that affect citrate and pH because there are well established epidemiologic differences in stone type and physiologic differences in acid-base handling by sex. Epidemiologically, younger women are more likely to have CaP stones, and this is likely because they have higher urine pH.
Exclusion criteria
- History of primarily brushite, uric acid, cysteine, or struvite stones
- History of severe acid-base abnormality, very low (less than 100mg/day) or very high (greater than 1500mg/day) urine citrate
- Participants who cannot stop diuretic medication or alkali supplementation for the course of the study period
- Use of drugs that can directly affect proximal tubule function (e.g., topiramate)
- Diagnosis of complete distal renal tubular acidosis
- Diagnosis of chronic kidney disease (eGFR \<60 mL/min/1.73m²)
Where
- Chicago, Illinois
Collaborators
National Institutes of Health (NIH), National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jan 12, 2026 · Source of record for eligibility and locations