Denver, Colorado, U.S., October 23, 2026
Kibow Therapeutics has presented Phase 2b clinical findings for KT-301, an investigational microbiome-based therapy being developed to slow the progression of Stage 4 chronic kidney disease (CKD). The results were featured at the American Society of Nephrology (ASN) Kidney Week 2026, held in Denver, Colorado. The randomized, double-blind, placebo-controlled study evaluated KT-301 in patients with advanced kidney disease, a population facing a high risk of progression to kidney failure. According to the conference abstract, patients receiving KT-301 experienced a significantly slower decline in kidney function over six months compared with those receiving placebo. The findings support further investigation of the gut-kidney axis as a potential therapeutic target. However, KT-301 remains investigational, and additional research is needed to establish its long-term benefits and safety.
KT-301 Targets the Gut-Kidney Connection
KT-301 is an investigational live biotherapeutic formulation containing three selected probiotic strains and prebiotic fibers. Developed by Kibow Therapeutics, the oral treatment is designed to influence the intestinal microbiome and help reduce the accumulation of uremic toxins associated with chronic kidney disease. In advanced CKD, declining kidney function can impair the body’s ability to eliminate waste products. Certain compounds produced through intestinal microbial metabolism may accumulate in the bloodstream, potentially contributing to inflammation and other complications. Researchers are investigating whether modifying gut microbial activity could help reduce this burden and influence disease progression. KT-301 is designed to support beneficial microbial activity and the metabolism of compounds associated with kidney disease. Unlike conventional treatments that primarily manage complications or established risk factors, this approach investigates whether targeting the intestinal environment could influence the progression of CKD itself. The company’s research reflects growing scientific interest in interactions between the intestinal microbiome, systemic inflammation and kidney function. Nevertheless, the proposed mechanism and its long-term clinical significance require continued validation through controlled studies.
Phase 2b Trial Reports Slower Kidney Function Decline
The Phase 2b study included 370 randomized patients with Stage 4 CKD, with 187 assigned to KT-301 and 183 assigned to placebo. Participants received the oral treatment twice daily with meals for six months, followed by a six-month open-label extension in which all participants received KT-301. The primary endpoint assessed changes in estimated glomerular filtration rate (eGFR), a measure used to evaluate kidney function. KT-301 demonstrated a significantly slower decline in kidney function over the initial six-month period compared with placebo. The reported between-group difference in creatinine-based eGFR change was 1.13 mL/min/1.73 m², with a p-value of 0.0118. The study also evaluated progression to end-stage renal disease (ESRD). Progression was numerically lower in the overall intention-to-treat population and significantly lower in the per-protocol analysis, where reported rates were 10.0% with KT-301 versus 19.1% with placebo. Additional analyses using creatinine and cystatin C measurements supported the kidney-function findings. Researchers reported that the treatment was well tolerated compared with placebo. The open-label extension also showed continued benefit, although interpretation of this phase requires caution because all participants received KT-301. These results are encouraging but do not establish that the treatment prevents kidney failure in all patients. Further studies will be needed to confirm the findings, assess longer-term outcomes and better understand which patients may benefit most.
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Mechanistic Research Supports Further Development
Alongside the clinical findings, Kibow presented laboratory research examining how KT-301 affects the gut microbiome and intestinal barrier. Investigators used a human intestinal microbial ecosystem simulator and a gut-barrier coculture model to study microbial activity, toxin levels and inflammatory markers. The laboratory findings showed increases in the short-chain fatty acids propionate and butyrate, reductions in selected uremic compounds and changes in microbial community composition. Researchers also observed changes in several inflammatory markers in the experimental system. These findings provide mechanistic support for the gut-kidney research strategy, but laboratory models cannot independently demonstrate clinical effectiveness in patients. For Kibow Therapeutics, the Phase 2b results represent an important milestone in developing microbiome-based approaches for kidney disease. The next steps will require further clinical evaluation to establish the durability of the observed effects, clarify the treatment’s safety profile and determine whether the findings translate into meaningful patient benefits. KT-301 has not been approved by the FDA for treating CKD. Its potential role in kidney care will depend on confirmatory evidence and the outcome of future regulatory review.
Source: Kibow Therapeutics press release
