Evaluation of a Novel Insulin Sensitizer in People With Type 1 Diabetes

1. Provision of signed and dated informed consent form
2. Stated willingness to comply with all study procedures and availability for the duration of the study
3. History of type 1 diabetes for at least one year
4. Age 18-45 years

5. HbA1c \<10%

   • BMI 18-35 kg/m2. Within this criterion, participants must have either BMI ≥25 or total daily insulin dose of ≥0.5 units/kg/day.
   • Currently utilizing closed-loop AID therapy that is compatible with Dexcom G7 CGM.
   • On stable regimen of non-diabetic medications for the last 6 months.
   • All screening labs within normal limits or not clinically significant.
   • Ability to take oral medication and be willing to adhere to the study drug/placebo for 12 weeks.
   • For females and males of reproductive potential: agreement to use adequate contraception during study participation and for an additional 2 weeks after the end of CIR-0602K administration.
   • For males of reproductive potential: use of condoms or other methods to ensure effective contraception with partner during study intervention.
   • Agreement to adhere to Lifestyle Considerations throughout study duration.

Exclusion Criteria:

• Current Pregnancy or currently breastfeeding.
• History of smoking tobacco products within the last two years.
• History of alcohol abuse or illicit drug abuse within 6 months of screening.
• Known history of human immunodeficiency virus (HIV).
• History of other significant disease (e.g., cardiac, cerebrovascular, gastrointestinal, liver, renal, or endocrine) that could, in the investigator's view, alter study outcomes
• Any surgical or medical condition which may significantly alter the absorption of the study drug including but not limited to the following: history of major gastrointestinal tract surgery such as gastrectomy, gastroenterostomy, bowel resection, gastric bypass, gastric stapling, or gastric banding, currently active inflammatory bowel syndrome.
• Current use of any antihyperglycemic medication beyond insulin (i.e., GLP-1 receptor agonists, SGLT2 inhibitors, etc.).
• Unstable doses (i.e., dose change within the last 4 months) of vasoactive medications (e.g., calcium-channel blockers, statins, angiotensin-converting enzyme inhibitors, diuretics, nitrates, alpha-blockers, beta-blockers, etc.).
• Daily use of anti-inflammatory medications (e.g., ibuprofen, aspirin, prednisone, dexamethasone, etc.).
• Diagnosis of peripheral neuropathy (assessed by screening monofilament exam).
• Macroalbuminuria (i.e., urine albumin: creatinine >300 mg per g).
• Retinopathy beyond mild, nonproliferative retinopathy.
• History of Level 3 hypoglycemia within the last 12 months.
• History of diabetic ketoacidosis (DKA) within the last 12 months.
• Screening electrocardiogram (ECG) findings indicative of arrhythmia, sinus node disease, or ischemic heart disease.
• Screening oxygen saturation \<90%
• History of hypersensitivity or prior adverse reaction to the study drug, closely-related compounds, or any of the stated ingredients.
• Use of concomitant medications with a known significant metabolism by CYP2C8 or CYP2C (including paclitaxel, phenytoin, warfarin, celecoxib, tolbutamide, or repaglinide) for the duration of the study.
• Participation in an investigational study (other than a non-treatment registry study) or received an investigational drug withing 30 days or 5 half-lives (whichever is longer) prior to randomization.