Chronic Kidney Disease (CKD) is a condition in which the kidneys lose function over time. Research has shown that individuals with kidney disease have an altered gut microbiome, the microorganisms that live in the human gastrointestinal tract. This imbalance in the gut microbiome can aid in the progression of CKD. Research also indicates that treatment with prebiotics, special plant fibers that promote the growth of healthy bacteria in the GI tract, can help restore balance in the gut microbiome. However, more understanding is needed regarding variability in the performance and composition of the gut microbiome in individuals with CKD, and how this population can be impacted by interventions with prebiotic supplements.

The Gut Microbiome and p-Inulin in CKD (TarGut) Study was formed to determine if the gut microbiome of patients with CKD could be improved with treatment of p-inulin, a type of prebiotic. After recruitment and enrollment, TarGut participants are evaluated for a period of 28 weeks. This 28-week study period consists of three phases: an 8-week pre-treatment phase, 12-week active treatment phase, and 8-week post-treatment phase. During the active treatment phase participants take the p-inulin supplement daily, but participants don’t receive any intervention during the pre- and post-treatment phases. Biological samples are collected from study participants every week during the 28-week study period and assessed to determine microbial composition and function.

The objective of the TarGut CKD Study is to determine if treatment with p-inulin will improve the gut microbiome in individuals with Chronic Kidney Disease. The study also seeks to identify how the gut microbiome varies in composition and function within and between patients with CKD.

Primary Outcome Measures: Stool samples will be evaluated for microbial composition and the variability, within-patient during the no treatment phases and between patients during the treatment phase, will be assessed. Adherence to the study intervention will also be assessed among participants.

Secondary Outcome Measures: Biological samples will be assessed for targeted metabolites and inflammatory markers. Within-patient and within-cohort results from the three study phases will be evaluated.

Inclusion Criteria: Study participants are age 18 years or older; have eGFR 15.0 to 50.0 ml/min/1.73 m2; albuminuria greater than 300 mg/g creatinine if eGFR is at least 45 ml/min/1.73 m2; and willing to use a highly effective birth control method, for women who are able to become pregnant.

Exclusion Criteria: Individuals are excluded from study participation if they have used pre- or pro-biotics in the past two months; consumed probiotic yogurt in the past two weeks; have cirrhosis or chronic active hepatitis; have inflammatory bowel disease, chronic diarrhea, or C. difficile infection; have or are being treated for periodontal infection; are planning to begin dialysis or receive a kidney transplant within nine months of enrollment; expected survival is less than nine months; are breastfeeding, pregnant, or may become pregnant; have HIV infection, chronic wound infection and osteomyelitis; have been treated with more than 10mg of prednisone for more than a week during the last three months or treated with immunosuppressive medications in the past six months; treated with proton pump inhibitors within the last month; have severe anemia; received antibiotic treatment within the past three to six months; are incarcerated; participating in another intervention study; or are unable to undergo frequent blood sampling.

This study is ongoing.