A Study to Investigate the Safety, Tolerability, and Pharmacokinetics of ONO-6414 Administered Orally in Healthy Adult Participants and Patients With Active Ulcerative Colitis

●Inclusion Criteria: \<Healthy Volunteers only\> * Male or female, age ≥18- to ≤55-year-old at the time of signing ICF. * Participants who are overtly healthy as determined by medical evaluation including medical history, physical examination, 12-lead ECG, vital signs measurements, and laboratory tests results, as evaluated by the investigator. * BMI of 18.0 to 32.0 kg/m2, inclusive, and a body weight of ≥50 kg at Screening. \<Patients only\> * Male or female, age ≥18-year-old at the time of signing ICF. * A diagnosis of ulcerative colitis (UC) must have been established at least three months prior to screening. \<Healthy Volunteers and Patients\> * Total abstinence, in accordance with the lifestyle of the participant, from at least 30 days prior to the first dose until at least 90 days after the last dose. * Ability to understand the study procedures described in the ICF. Willingness and ability to comply with the protocol, and provides written informed consent prior to study participation. * Willingness and ability to swallow study intervention tablets and/or suspension. * Willing to take off dentures or mouth piercing at the time of dosing. ●Exclusion Criteria: \<Healthy Volunteers only\> * Mentally or legally incapacitated. * History or presence of clinically significant medical, surgical or psychiatric condition or disease that in the opinion of the investigator or medical monitor might confound the results of the study or pose an additional risk to the participa…