A Phase 2 interventional study of Acetazolamide and Placebo in Type 1 Diabetes, sponsored by University of California, San Diego. Recruiting at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-06-17.
Sponsored by University of California, San Diego · Phase 2, Interventional, and Treatment
The goal of this study is to learn about the effect of the study drug acetazolamide in individuals with Type 1 Diabetes. Specifically, whether acetazolamide provides benefits to the kidneys while minimizing any side effects of the drug. These changes will be measured by laboratory tests that tell us how well the kidneys are functioning.
A Randomized, Double-blind, Placebo-Controlled, Crossover Trial (RCT) to explore the effects of 250mg acetazolamide in individuals with type 1 diabetes. Participants will be randomized to Treatment Group A or Treatment Group B. Randomization will be blinded, but one of these treatment groups will receive 250mg (milligram) BID (twice daily) of acetazolamide for 10 weeks - receive no study drug for 2 weeks - then receive placebo for 10 weeks; the other will receive placebo for 10 weeks - receive no study drug for 2 weeks - then receive 250mg BID of acetazolamide for 10 weeks. Both participants and study staff will be blinded to the study treatment group with only the research pharmacy staff being unblinded.
To measure mGFR (measured glomerular filtration rate), an Iohexol GFR (glomerular filtration rate) procedure will be completed at the beginning and end of each treatment period. A standard protocol for the procedure will be followed that has been used in multiple studies. Iohexol (Omnipaque 300®) will be used in order to obtain a precise measure of mGRF throughout the course of the test. Iohexol will be prepared by the UCSD (University of California, San Diego) Investigational Drug Services at the ACTRI (Altman Clinical and Translation Research Institute) by drawing up 5mL into a syringe per standard pharmacy protocol. The iohexol will be dispensed to a nurse or research coordinator who will weigh the syringe prior to infusion and again after infusion to assess exact dosage delivered.
A study nurse will insert 1 IV (intravenous) line in the hand or arm for the infusion of iohexol. They will then insert a second IV in the opposite arm for blood collection. Serial blood draws will occur throughout the procedure relative to the time of iohexol infusion. A study nurse will infuse iohexol over a 1-2 minute period, flush with 10mL (milliliter) of normal saline and remove the IV. Blood samples will be collected at the following time points for mGFR analysis:
10,925 studies on the registry are indexed under Diabetes Mellitus; 1,319 are open to participants now.
This study's planned enrollment of 25 is below the median of 80 across 8,367 interventional studies indexed under Diabetes Mellitus.
Browse Diabetes Mellitus studies →University of California, San Diego is the lead sponsor of 958 studies on the registry; 191 are open to participants now.
Of its 110 completed or terminated interventional studies of FDA-regulated products, 70 (64%) have results posted.
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Exclusion Criteria:
250mg Acetazolamide administered twice a day for 10 weeks followed by Placebo Comparator administered twice a day for 10 weeks.
Drug: Acetazolamide · Drug: Placebo
Placebo Comparator administered twice a day for 10 weeks followed by 250mg Acetazolamide administered twice a day for 10 weeks.
Drug: Acetazolamide · Drug: Placebo
Acetazolamide is a potent carbonic anhydrase inhibitor that acts on the renal proximal tubule. Through this mechanism, it inhibits proximal tubule sodium reabsorption.
Standard pharmaceutical filler will be capsulated and packaged identically to the acetazolamide.
Change in mGFR percent
The difference in mGFR percent between acetazolamide versus placebo as measured by the iohexol procedure.
Time frame: 10 weeks
Preservation of Serum Bicarbonate
The preservation of serum bicarbonate concentrations at ≥ 20 meq/L (milliequivalents per liter) from pre-dosing to post-treatment iohexol procedure.
Time frame: 10 weeks
Preservation of Serum Potassium
The preservation of serum potassium concentrations at ≥ 3.2 meq/L from pre-dosing to post-treatment.
Time frame: 10 weeks
Change is albuminuria
The difference in change in albuminuria between acetazolamide versus placebo as measured by urinalysis.
Time frame: 10 weeks
Plan to share: No
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University of California, San Diego