Efficacy and Safety of Oral Controlled-release Nicotinic Acid (CIR-NA) for the Remission of Prediabetes. (CONCEPT)

The goal of this clinical trial is to prevent the change from prediabetes (a pre-stage of type 2 diabetes mellitus (T2DM)) to T2DM in participants with prediabetes using oral CIR-NA (a nicotinic acid formulation that is designed to be released after reaching the ileum) which targeted the gut microbiota. The main questions it aims to answer are: 1. Is CIR-NA effective and does it prevent the change from prediabetes to T2DM? 2. Is the safety of CIR-NA that was observed in the Phase I clinical trial confirmed in subjects with prediabetes? Researchers will compare CIR-NA to a placebo (a look-alike substance that contains no drug) in terms of an extended safety evaluation including safety laboratory assessments, physical examination, vital signs and 12-lead ECG. Participants will: Take CIR-NA or a placebo every day for 26-weeks. Visit the clinic at week 1 and subsequently once every 4 weeks for checkups and tests. Receive standardized lifestyle recommendations regarding nutrition and physical activity during the intervention.