The BASE Study: Bicarbonate Administration to Stabilize Estimated Glomerular Filtration Rate (eGFR)
Condition: Chronic Kidney Disease
MeSH terms: Kidney Diseases; Renal Insufficiency, Chronic
Intervention: Lower Dose Sodium Bicarbonate; Higher Dose Sodium Bicarbonate; Placebo
Intervention description: Lower dose oral Sodium Bicarbonate (0.5 milliequivalents (mEq)/kg-LBW/day); Higher dose oral Sodium Bicarbonate (0.8 mEq/kg-LBW/day); Oral placebo equivalent to either 0.5 mEq/kg-LBW/day or 0.8 mEq/kg-LBW/day of Sodium Bicarbonate
Phase: Phase 3
Study type: Interventional
Primary purpose: Other
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Enrollment: 194.0
Sex: All
Minimum age: 18 Years
Healthy volunteers: No

Summary:

      The two doses of sodium bicarbonate being tested are 0.5 and 0.8 mEq/kg-lean body weight
      (LBW) per day. Sodium bicarbonate, also known as baking soda, may help prevent kidney failure
      in people with chronic kidney disease. However, the dose to prescribe in order to test this
      possibility in a clinical trial is uncertain. The BASE pilot clinical trial will help
      determine the best dose of sodium bicarbonate to prescribe in a future study that will test
      the long-term safety and efficacy of sodium bicarbonate as a treatment to preserve kidney
      function in individuals with chronic kidney disease.
    

Eligibility criteria:

        Inclusion Criteria:

          1. Serum bicarbonate 20-28 mEq/L at screening (the average of the two most recent values
             in Baseline must be 20-28 mEq/L prior to randomization)

          2. Moderate to severe chronic kidney disease (CKD) at the time of screening, defined as
             one of the following:

               -  eGFR 20-44 ml/min/1.73m2 or

               -  eGFR 45-59 ml/min/1.73m2 plus random urinary albumin:creatinine (ACR) ≥100 mg/gm

          3. Blood pressure <160/100 mm Hg at screening (must be <150/100 mm Hg prior to
             randomization)

          4. Lean body weight 38.0-96.0 kg at the time of screening

          5. Age allowing legal consent without parental involvement (18-21 years, depending on
             individual state regulations)

          6. Able to provide consent

          7. Able to travel to study visits

          8. Able to read English

          9. In the opinion of the site investigator, willing and able to follow the study
             treatment regimen and comply with the site investigator's recommendations

         10. In the opinion of the site investigator, medically stable

        Exclusion Criteria:

          1. Use of chronic daily oral alkali (such as sodium bicarbonate, sodium citrate,
             potassium citrate, etc) with one exception: calcium carbonate ≤1500 mg/day is allowed,
             as some will take this for the indication of bone health

          2. On five or more antihypertensive and/or diuretic agents, regardless of the indication

          3. Serum potassium <3.3 or ≥5.5 mEq/L at screening (must be 3.5-5.5 mEq/L prior to
             randomization)

          4. Self-reported vegetarian

          5. New York Heart Association Class 3 or 4 heart failure symptoms, known left ventricular
             ejection fraction ≤30%, or hospital admission for heart failure within the past 3
             months

          6. Frequent urinary tract infections (≥2 in the past year)

          7. Presence of indwelling urinary catheter or urinary conduit (such as neobladder or
             urostomy)

          8. Factors judged to limit adherence to interventions (e.g., alcoholism, history of
             missing clinic visits, chronic gastrointestinal disorder that makes compliance with
             the intervention unreliable)

          9. Organ transplant recipients (excluding cornea)

         10. Active glomerular disease requiring or potentially requiring immunosuppressive
             treatment

         11. Chronic immunosuppressive therapy (for ≥3 months) for any indication. This does not
             include oral steroids <10 mg per day, inhaled steroids, or topical steroids

         12. Anticipated initiation of dialysis or kidney transplantation within 12 months as
             assessed by the site investigator

         13. Current participation in another interventional research study

         14. Malignancy requiring therapy within 2 years (basal or squamous cell skin carcinoma and
             localized prostate cancer are exempted)

         15. Pregnancy or planning to become pregnant or currently breast-feeding. Women of
             childbearing potential (pre-menopausal and not surgically sterilized) will have urine
             pregnancy test before enrollment.

         16. Life expectancy <12 months as determined by the site investigator

         17. Institutionalized individuals, including prisoners and nursing home residents

         18. Plans to leave the immediate area within the next 12 months

         19. Routinely leaves town for multiple weeks each year such that protocol visits would be
             missed

         20. Chronic use of supplemental oxygen

         21. Use of both angiotensin-converting-enzyme inhibitor (ACEI) and Angiotensin II Receptor
             Blockers (ARBs)