The COMBINE Study: The CKD Optimal Management With BInders and NicotinamidE

Inclusion criteria

• Patients with estimated glomerular filtration rate (eGFR) 20-45 ml/min/1.73m2
• Age 18-85 years
• Serum phosphate ≥ 2.8 mg/dL
• Platelet count ≥ 125,000/mm3
• Able to provide consent
• Able to travel to study visits
• Able to eat at least two meals a day
• In the opinion of the site investigator, willing and able to follow the study treatment regimen and comply with the site investigator's recommendations.

Exclusion criteria

• History of allergic reaction to nicotinamide, niacin (excluding flushing), multivitamin preparations, or lanthanum carbonate
• Liver disease, defined as known cirrhosis by imaging or physician diagnosis, documented alcohol use > 14 drinks/week, or aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, or total bilirubin concentrations > 2 times the upper limit of the local laboratory reference range
• Creatine kinase (CK) concentrations > 2 times the upper limit of the local laboratory reference range
• Major hemorrhagic event within the past six months requiring in-patient admission
• Blood or platelet transfusion within the past six months
• Secondary hyperparathyroidism (PTH > 5 times the upper limit of normal range for the laboratory) or currently taking cinacalcet (Sensipar)
• Current, clinically significant malabsorption, as determined at the discretion of the site investigator
• Anemia (screening Hg < 9.0 g/dl)
• Serum albumin < 2.5 mg/dl
• Anticipated initiation of dialysis or kidney transplantation within 12 months as assessed by and at the discretion of the site investigator.
• Use of immunosuppressive medications (stable oral steroids ≤ 10 mg of prednisone/day or inhaled steroids are exempted)
• In the opinion of the site investigator, active abuse of alcohol or drugs
• Recent (within the last 14 days) initiation or change in dose of treatment with 1,25 (OH)2 vitamin D or active vitamin D analogues (paricalcitol or hectorol). Patients on stable doses of these agents initiated more than 14 days prior to screening are eligible to participate.
• Current or recent treatment (within the last 14 days) with phosphate binder or niacin/nicotinamide > 100 mg/day
• Current participation in another clinical trial or other interventional research
• Currently taking investigational drugs
• Institutionalized individuals, including prisoners and nursing home residents
• Malignancy requiring therapy within 2 years (basal or squamous cell skin carcinoma and localized prostate cancer are exempted)

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