Metabolic Impacts of Ren-Nu: A Dietary Program for Polycystic Kidney Disease (PKD-KETO)

Short-Term Metabolic Impacts of Ren-Nu: A Dietary Program for Individuals With Polycystic Kidney Disease

This is a 16 week pilot study of the impact of a nutritionist led ketogenic diet (Ren-Nu) supplemented with the medical food KetoCitra on autosomal dominant polycystic kidney disease.

Study Overview

• Status: Recruiting
• Conditions: Autosomal Dominant Polycystic Kidney Disease (ADPKD)
• Intervention / Treatment: Dietary supplement: Ren-Nu and KetoCitra

Detailed Description

The goal of the Ren-Nu program aims to improve the metabolic health of ADPKD patients by implementing a plant-focused, kidney-safe, ketogenic diet supported by medical food KetoCitra®. It is a dietitian-led, online group program focused on ketogenic metabolic therapy with rolling recruitment .

For 12 weeks, participants will be remotely directed through the Ren-Nu program by an experienced renal dietitian where they will learn to implement diet and lifestyle changes by completing weekly web-based classes on nutrition principles and food preparation. A continuous glucose monitor (CGM) will be provided for use during the study. Additionally, they will use a smartphone application to track nutrient intake, self-monitor biomarkers, implement mindfulness practice, and participate in facilitated discussions to build community support. Each participant will meet remotely with the renal dietitian and complete laboratory safety monitoring throughout the program to tailor dietary recommendations for optimal compliance. The study will involve visits to the research institution, histories, physical examinations and laboratory work.

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Chloe Booth; Phone Number: 216-444-5053; Email: boothc2@ccf.org
• Study Contact Backup: Name: Richard Fatica, MD; Phone Number: 216-445-9953; Email: faticar@ccf.org

Study Locations

• United States
  • Ohio
    • Cleveland, Ohio, United States, 44195
      • Recruiting
      • Cleveland Clinic
      • Principal Investigator: Richard Fatica, MD
      • Contact: Chloe Booth; Phone Number: 216-444-5053; Email: boothc2@ccf.org
      • Contact: Richard Fatica, MD; Phone Number: 216-445-9953; Email: faticar@ccf.org

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult (18 years or older)

  • Diagnosis of ADPKD by a physician.
  • Estimated glomerular filtration rate (eGFR) ≥ 30 mL/min/1.73 m2 at screening using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equation.
  • Appropriate control of blood pressure (i.e. entry reading <140/90) including the use of BP medications for diagnosis of hypertension.
  • BMI ≥ 25 (accounting for muscle mass)
  • Own an at-home blood pressure monitor (no brand requirements)
  • Able to complete study-related activities (e.g., attend online classes, complete questionnaires, and proper use of medical devices)

Exclusion Criteria:

• Intolerance or allergy to any of the ingredients in the provided medical food

  • Severe or rare underlying health conditions may cause a safety risk when taking the medical food. Those underlying health conditions will be assessed by the enrolling physician and include but are not limited to:

    • History of hyperkalemia
    • Heart failure
    • Liver cirrhosis
    • Chronic kidney disease stage 4 or greater, or other renal condition that severely impairs bone mineral homeostasis.
    • HIV infection
    • Chronic drug or alcohol abuse
    • Chronic malabsorption syndrome
    • Malignancy (non-melanoma skin cancer exempted)
    • Autoimmune disease
    • Pregnant, planning to be pregnant, or nursing during the course of the study
    • Chronic history of recurrent urinary tract infections (UTI) (≥ 3 UTIs per year)
    • Diagnosis of aneurysm
    • Indigestion due to hypochlorhydria (low stomach acid)
    • Any other condition, that in the opinion of the enrolling physician, makes the subject an unsuitable candidate for the study.

  • Current use of any of the following medications or supplements which could affect safety or compliance with this study:

    • The medical food, KetoCitra®.
    • Urine alkalizing agents such as sodium bicarbonate or potassium citrate
    • Citrate treatments
    • Immunosuppressive treatment
    • Tolvaptan
    • Potassium-sparing diuretics
    • Somatostatin analogs
    • Aluminum-containing supplements or medications such as aluminum antacids (e.g. Maalox) or aluminum-based phosphate binders.
    • SGLT2 inhibitors
  • Participation in another therapeutic intervention trial.
  • Following a highly specialized or extreme diet that is incompatible with the interventional nutrition program (e.g. carnivore, very high protein diet for elite athletes, etc.)
  • Food sensitivities or allergies that are incompatible with the interventional nutrition program.
  • The subject is already adhering to a form of a ketogenic diet or related fasting regimen.
  • Current or past history of disordered eating or feeding behaviors.
  • History of gastric bypass.
  • Active diagnosis of ulcerative colitis, Irritable Bowel Syndrome, Crohn's, or Gallbladder Disease.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Pilot study on ketogenic diet Ren-Nu and KetoCitra supplement on ADPKD; Nutritional counseling and instruction in a ketogenic diet and nutritional food supplement	Dietary supplement: Ren-Nu and KetoCitra; This is a structured, nutritionist monitored program supplemented with a nutritional food product, while monitoring metabolic parameters; Other Names: intermittent fasting; Continuous glucose monitoring; Nutritional counseling

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Serum Renal Function	Change from baseline of renal function assessment as measured by creatinine based estimated glomerular filtration rate.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in Serum Hepatic Function Biomarkers	Change from baseline of serum liver panel biomarkers to track safety signals. Biomarkers include: AST (U/L), ALT (U/L), and LDH (U/L). Measured via standard clinical laboratory assays.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in Glycemic Control	Change from baseline of glycemic control as measured by aggregate of Hgb A1c and Homeostatic model assessment of insulin resistance (HOMA-IR).	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in Systemic Inflammation Markers	Change from baseline of inflammatory biomarkers as an aggregate using: serum C-reactive protein [(CRP) mg/dL] and homocysteine (umol/L). Measured via standard clinical laboratory assays.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in Serum Measures of Lipids	Change from baseline of of lipids using fasting serum lipid panel to track cholesterol and fat levels. This includes: total cholesterol (mg/dL), HDL cholesterol (mg/dL), LDL cholesterol (mg/dL), and triglycerides (mg/dL).	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in 24-Hour Urine Collection to track Lithogenic Risk	Change from baseline of 24-hour urine analytes in aggregate to assess lithogenic risk. The analytes will include calcium (mg/day), creatinine (mg/day), citrate (mg/day), oxalate (mg/day), uric acid (mg/day), sodium (mmol/day), chloride (mmol/day), magnesium (mg/day), ammonium (mmol/day), sulfate (mmol/day), phosphorus (mg/day), urea nitrogen (g/day), and urine pH. Measured via standard clinical laboratory assays.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in Glycemic Variability via a Continuous Glucose Monitor (CGM)	Change from baseline in glycemic variability includes mean glucose (mg/dL) measured over a period of time and compared to before and at the end of the Ren-Nu program. This will be measured using the FreeStyle Libre 3 System.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in Anthropometric Measures	Change from baseline in body weight (kg) and body mass index (kg/m²), calculated from measured height and weight using standardized clinic procedures.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in Blood Pressure	Change from baseline in systolic and diastolic blood pressure. Seated blood pressure (mmHg) is taken throughout the 4 week orientation period and the 12 week nutritional dietary program. This is measured using a calibrated automated blood pressure machine after 5 minutes of rest.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in Serum Fatty Acid	Change from baseline of serum free fatty acid (FFA, mmol/L).	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in health-related quality of life as assessed by the Quality of Life: Short-Form Health Survey 12 (SF-12v2)	Participants will complete the Quality of Life: Short-Form Health Survey 12 (SF-12v2) on Day 0 and Day 120. Scores are standardized by mean. A higher score indicates a better-than-average health-related quality of life, while a lower score suggests a below-average health-related quality of life.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Change in self reported mental and physical health outcomes	This is reported as a change in participant reported mental health status measured via both the Quality of Life: Short-Form Health Survey 12 (SF-12v2) and the study-developed Ren-Nu Outcomes survey. The outcomes survey assesses topics such as final weight (kg), final blood pressure (mmHg), current PKD related symptoms, and changes to medications/supplements.	Visit 2 (Day 0) before Ren-Nu and Visit 3 (Day 120) after Ren-Nu
Assessment of nutrition knowledge following the structured nutrition education program	Self reported participant nutrition knowledge of the nutritional program at the end of the program. This is a study-developed questionnaire and these questions are multiple choice with a low score reflecting lower nutritional knowledge of the dietary program and a high score reflecting higher nutritional knowledge of the dietary program.	Visit 3 (Day 120) after Ren-Nu
Assessment of dietary intervention tolerability following the structured nutrition education program	Self reported participant tolerability of the nutritional program at the end of the program. This is a study-developed questionnaire and questions are multiple choice with a low score reflecting a lower tolerability to the dietary program and a high score reflecting higher satisfaction with the program.	Visit 3 (Day 120) after Ren-Nu
Assessment of dietary intervention feasibility following the structured nutrition education program	Self reported participant feasibility of the nutritional program at the end of the program. This is a study-developed questionnaire and questions are multiple choice with a low score reflecting lower feasibility of the dietary program and a high score reflecting higher feasibility of the dietary program.	Visit 3 (Day 120) after Ren-Nu

Collaborators and Investigators

• Sponsor: Richard Fatica
• Collaborators: Santa Barbara Nutrients
• Investigators: Principal Investigator: Richard Fatica, MD, The Cleveland Clinic; Study Director: Thomas Weimbs, PhD, Santa Barbara Nutrients

Study record dates

Study Major Dates

• Study Start (Actual): February 25, 2026
• Primary Completion (Estimated): February 1, 2027
• Study Completion (Estimated): February 1, 2028

Study Registration Dates

• First Submitted: January 27, 2026
• First Submitted That Met QC Criteria: March 3, 2026
• First Posted (Actual): March 6, 2026

Study Record Updates

• Last Update Posted (Actual): March 6, 2026
• Last Update Submitted That Met QC Criteria: March 3, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: ADPKD; Keto diet; polycystic kidneys; Ren-Nu; KetoCitra
• Additional Relevant MeSH Terms: Ciliopathies; Urogenital Diseases; Male Urogenital Diseases; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Genetic Diseases, Inborn; Congenital Abnormalities; Abnormalities, Multiple; Kidney Diseases, Cystic; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Polycystic Kidney Diseases; Polycystic Kidney, Autosomal Dominant; Health Care Quality, Access, and Evaluation; Investigative Techniques; Epidemiologic Methods; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Data Collection; Health Care Evaluation Mechanisms; Quality of Health Care; Public Health; Environment and Public Health; Epidemiologic Measurements; Blood Chemical Analysis; Clinical Chemistry Tests; Diagnostic Techniques, Endocrine; Monitoring, Physiologic; Nutrition Assessment; Continuous Glucose Monitoring
• Other Study ID Numbers: 24-893; SBN2504RF (Other Grant/Funding Number: Santa Barbara Nutrients, INC)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No