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

Inclusion Criteria: 1. Male and female participants ≥ 18 to \< 80 years of age (at the time of signing the informed consent). 2. Body mass index ≥ 20 kg/m². 3. Ability to understand and comply with the protocol. 4. Signed written informed consent. 5. Diagnosed prediabetes according to the current EASD/DDG guidelines. Prediabetes is present if at least one value is in the prediabetes range, but no value is in the T2DM range. 6. Subgroup-specific: MASLD fibrosis score ≥ -1.455. Exclusion Criteria: 1. Presence or a history of type 2 diabetes mellitus according to the current EASD/DDG guidelines. 2. Participants with relevant medical conditions (based on evaluation of medical history and screening assessments), unstable and uncontrolled underlying diseases, e.g., hypothyroidism, asthma, COPD or arterial hypertension, can be excluded per judgment of the Investigator. 3. Renal impairment (glomerular filtration rate \<60 ml/min/1.73). 4. Impairment of hepatic function (one or more of liver enzymes alanine transaminase, aspartate transaminase and gamma glutamyl transferase \[\> 3-fold compared to normal range\]). 5. Current infection with hepatitis B or C. 6. Clinically relevant abnormal findings in medical history or screening assessments which, in the opinion of the Investigator, may put the participant at risk when participating in the trial or provide difficulties in interpreting the trial data. 7. Current or history of malignancy except for completely resected basal cell carcinoma and squamous cell carcinoma of the skin. 8. Alcohol or drug abuse within the last 2 years at the discretion of the Investigator. 9. Subgroup-specific: Any circumstances which could contradict MRI and MRS imaging. For details, see Informed Consent Form (ICF) for additional examinations. 10. Regular use of any prescribed or over-the-counter medication, food supplements or herbal preparations, which cannot be terminated 3 weeks before baseline and during the full duration of the trial. Pain medication (e.g., ibuprofen or paracetamol), topical allergy medicines, hormone replacement therapies and oral contraceptives according to label are allowed. Medications in stable doses for controlling stable underlying diseases (see exclusion criterion 2) are also allowed per judgment of the Investigator. 11. Use of antibiotics (systemic or gut-acting \[non-absorbed\]) within 8 weeks prior to the first dose of IMP. 12. Long term use of higher doses of proton pump inhibitors, targeted H2-receptor antagonists or antacid formulations (i.e., doses equivalent to \> 40 mg pantoprazole per day). 13. Known hypersensitivity towards any component of the CIR-NA or placebo tablets. 14. Participation in a clinical trial (as defined in the clinical trial regulation (CTR)), currently or within 4 weeks prior to screening for this trial or intake of an IMP within the last 8 weeks or 5 half-lives (whichever is longer) prior to screening (or longer, if necessary, at the Investigator's discretion). 15. Participants under legal supervision or guardianship, including participants who are committed to an institution by virtue of an order issued either by the judicial or the administrative authorities. 16. Participants who are dependent on the Investigator or the Sponsor. 17. Pregnant or breastfeeding women. 18. Women of childbearing potential (WoCBP) not using highly effective contraception till at least 1 month after last dosing of IMP. 19. Male participants with female partners of childbearing potential who are not willing to use a highly effective contraception till at least 1 month after last dosing of IMP. 20. Any other circumstances or medical conditions which could contradict a trial participation and lead the Investigator to assess the participant as unsuitable for trial participation.