Research

Hormonal

Engineered bacteria (SYNB1020) that overproduce arginine to convert gut ammonia into L-arginine successfully lower systemic ammonia and improve survival in animal models of liver failure, but failed to show efficacy in a Phase Ib/IIa clinical trial for cirrhosis patients.

While engineered bacteria show promise in animals for clearing liver toxins, current clinical trials for liver disease patients have not yet succeeded. Do not expect this specific therapy to be available or effective for cirrhosis at this time.

ModerateQualifiesMEDIUM confidence
All these strains showed promising results in preclinical models of hyperammonemia, in lowering ammonia and improving the survival of mice and rats... However, the randomized, double-blind, placebo-controlled phase Ib/IIa study (NCT03447730) in patients with cirrhosis and elevated blood ammonia yielded negative results, with no difference in blood ammonia or changes in other exploratory endpoints noted relative to placebo despite evidence of activity of the strain as measured by plasma and urinary nitrate increases.
Dragos Ciocan et al. · Acta Physiologica · 2023

Why this rating

Strong preclinical data (multiple animal models) but failed Phase Ib/IIa human trial; development halted.

Source

Engineering bacteria to modulate host metabolism

Dragos Ciocan et al. · Acta Physiologica · 2023

DOI 10.1111/apha.14001

narrative_reviewCited 16×
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DOI resolved against Crossref · corpus check 2026-06-10

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