Safety and Pharmacokinetics of Oral Controlled-ileocolonic-release Nicotinamide (CICR-NAM)

Main inclusion and exclusion criteria Inclusion criteria for the SAD and MAD parts with healthy subjects: 1. Male and female subjects aged 18 to 75 years. 2. Healthy subjects without relevant medical conditions. 3. Ability to understand and comply with the protocol. 4. Signed written Informed Consent. 5. A BMI of 18.5 to 29.99 kg/m². 6. Non-smoker or light smoker (average of \<7 cigarettes per week) and no history of longterm, heavy smoking (\>10 pack-years). Inclusion criteria for the MD-IBD part: 1. Male and female patients with IBD and 18 to 75 years of age. 2. Ability to understand and comply with the protocol. 3. Signed written Informed Consent. 4. Documented diagnosis of relapsing ileal, ileocolonic or colonic Crohn disease or relapsing ulcerative colitis. 5. Concomitant therapy (background medication) for inflammatory bowel disease: none or stable 8 weeks before baseline. 6. No signs of malignancy. Exclusion criteria for the SAD and MAD part with healthy subjects: 1. Pre-existing relevant medical conditions. 2. Clinically relevant abnormal findings in medical history or screening assessments. 3. Participation in a clinical study. 4. Use of any prescribed or over-the-counter medication, food supplements or herbal preparations. 5. Use of antibiotics (systemic or gut-acting \[non-absorbed\]). 6. Pregnant or breastfeeding women or women of childbearing potential and male participants with female partners of childbearing age not using highly effective contraception till at least 1 month after last dosing of investigational medicinal product (IMP). 7. Legal incapacity. 8. Indications that the patient may be unable to comply with the study procedures, e.g. language barriers precluding adequate understanding or cooperation Exclusion criteria for the MD-IBD part: 1. Diagnosis of indeterminate colitis, microscopic colitis, ischaemic colitis, infectious colitis, radiation colitis or diverticular disease (except for diverticles accompanying CD). 2. Current or past diagnosis of complex fistulae or intra-abdominal or peritoneal abscesses. 3. Strictures with obstructive symptoms. 4. Pregnant or breastfeeding women or women of childbearing potential and male participants with female partners of childbearing age not using highly effective contraception till at least 1 month after last dosing of investigational medicinal product (IMP). 5. Legal incapacity. 6. Indications that the patient may be unable to comply with the study procedures, e.g. language barriers precluding adequate understanding or cooperation