An interventional study of Carbohydrate Restricted, Plant Dominant Diet and usual diet in Autosomal Dominant Polycystic Kidney Disease (ADPKD), sponsored by Assaf-Harofeh Medical Center. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-06-26.
Sponsored by Assaf-Harofeh Medical Center · Not applicable, Interventional, and Basic science
Autosomal dominant polycystic kidney disease (ADPKD) is characterized by progressive cyst growth and declining kidney function. Inflammatory pathways, including those mediated by monocyte chemoattractant protein-1 (MCP-1), are increasingly recognized as contributors to disease progression. Metabolic alterations in cystic epithelial cells may influence inflammatory signaling, suggesting a potential role for dietary interventions targeting metabolic pathways.
This study is a prospective, randomized, open-label crossover trial designed to evaluate the effect of a carbohydrate restricted, plant dominant dietary intervention on urinary MCP-1 levels in adults with ADPKD. Participants will be randomized to one of two sequences: dietary intervention followed by usual diet, or usual diet followed by dietary intervention, with a washout period between study phases. Each study period will last 12 weeks.
The primary objective is to assess within subject differences in urinary MCP-1/creatinine ratio between the dietary intervention and usual diet conditions. Secondary outcomes include measures of metabolic parameters, insulin resistance, dietary adherence, and safety.
This study aims to explore whether a structured dietary approach may influence intrarenal inflammatory activity in ADPKD and provide preliminary data to inform future interventional studies.
185 studies on the registry are indexed under Polycystic Kidney, Autosomal Dominant; 42 are open to participants now.
This study's planned enrollment of 36 is below the median of 51 across 138 interventional studies indexed under Polycystic Kidney, Autosomal Dominant.
Browse Polycystic Kidney, Autosomal Dominant studies →Assaf-Harofeh Medical Center is the lead sponsor of 267 studies on the registry; 43 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HbA1c
A blood test of average blood sugar over the past two to three months, given as a percentage or in mmol/mol. 6.5% (48 mmol/mol) or more is the usual threshold for diabetes, normally confirmed by a second test.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants receive a carbohydrate restricted, plant dominant diet for 12 weeks, followed by a washout period and then usual diet for 12 weeks.
Behavioral: Carbohydrate Restricted, Plant Dominant Diet · Behavioral: usual diet
Participants follow their usual diet for 12 weeks, followed by a washout period and then the dietary intervention for 12 weeks.
Behavioral: Carbohydrate Restricted, Plant Dominant Diet · Behavioral: usual diet
A structured dietary intervention targeting approximately 20% of total daily energy intake from carbohydrates (range 15-25%), with a plant dominant composition. Energy and protein intake are prescribed based on adjusted body weight. The intervention is not ketogenic and is not intended to induce nutritional ketosis. Participants receive individualized dietary counseling and ongoing support from a registered dietitian.
Participants continue their habitual diet without specific dietary intervention or structured nutritional guidance.
Change in Urinary MCP-1/Creatinine Ratio
Urinary MCP-1 levels will be measured in first morning urine samples and normalized to urine creatinine (MCP-1/creatinine ratio). For each study period, two samples will be collected within the final week (2-5 days apart), and the mean value will be used. The primary outcome is the within subject difference in MCP-1/creatinine ratio between the dietary intervention and usual diet conditions.
Time frame: Baseline and End of each 12-week study period (weeks 0,12, 18 and 30)
Association Between Carbohydrate Intake and MCP-1
Mean carbohydrate intake during each study period will be calculated from repeated dietary assessments. The association between carbohydrate intake and urinary MCP-1/creatinine ratio will be evaluated to explore a potential dose response relationship.
Time frame: Baseline and End of each 12-week study period (weeks 0,12, 18 and 30)
Association Between Change in HOMA-IR and MCP-1
The association between changes in insulin resistance (HOMA-IR) and changes in urinary MCP-1/creatinine ratio will be evaluated within individuals across study conditions.
Time frame: Baseline and End of each 12-week study period (weeks 0,12, 18 and 30)
Dietary Adherence and MCP-1 Response
Dietary adherence will be defined as the proportion of dietary assessments in which carbohydrate intake falls within the target range (15-25% of total energy intake). The association between adherence and urinary MCP-1/creatinine ratio will be evaluated.
Time frame: Baseline and End of each 12-week study period (weeks 0,12, 18 and 30)
Change in Metabolic and Biochemical Parameters (Safety Outcomes)
Changes in selected metabolic and biochemical parameters, including serum bicarbonate, LDL cholesterol, and estimated glomerular filtration rate (eGFR), will be assessed between study conditions to evaluate the safety of the dietary intervention.
Time frame: Baseline and End of each 12-week study period (weeks 0,12, 18 and 30)
Mediation Analysis of Insulin Resistance and MCP-1
Exploratory analysis to evaluate whether changes in insulin resistance (HOMA-IR) mediate the relationship between dietary intervention and urinary MCP-1/creatinine ratio using regression based mediation models.
Time frame: Baseline and End of each 12-week study period (weeks 0,12, 18 and 30)
Gene Expression of CPT1A and ACOX1
Pre-specified exploratory analysis of gene expression of CPT1A and ACOX1, key regulators of fatty acid oxidation pathways, measured in peripheral blood samples. Expression levels will be evaluated in relation to dietary intervention and changes in urinary MCP-1/creatinine ratio.
Time frame: Baseline and End of each 12-week study period (weeks 0,12, 18 and 30)
Exploratory Analysis of the Gut Microbiome
Exploratory analyses will evaluate changes in gut microbial composition associated with the dietary intervention. Stool samples collected at baseline and at the end of each study period will undergo microbiome analysis. Changes in microbial diversity and taxonomic composition will be explored and correlated with dietary adherence, urinary MCP-1 levels, and metabolic parameters. Given the exploratory nature of these analyses and the limited sample size, findings will be considered hypothesis-generating.
Time frame: Baseline and End of each 12-week study period (weeks 0,12, 18 and 30)
Health-Related Quality of Life (SF-36)
Pre-specified exploratory assessment of health-related quality of life using the Short Form-36 (SF-36) questionnaire.
Time frame: Baseline and end of each 12-week study period (Weeks 0, 12, 18, and 30)
No study locations are listed for this record.
Plan to share: Undecided
Start is estimated for Jul 2026; primary completion for Jan 2029, 29 months later.
Of 22 interventional studies with no phase under Polycystic Kidney, Autosomal Dominant, half reached primary completion within 30 months of starting (the median), counting those still running; a quarter within 19 and three quarters within 54. This study's planned 29 months is close to that.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Apr 2026. You cannot join it, but the record below documents what was studied.
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