Bridge Biotherapeutics (KQ288330) announced the first patient dosing of BBT-401 in its open label, proof of mechanism study to examine the drug's efficacy and safety in active ulcerative colitis when delivered rectally to the colon (NCT04478825). The study will include a total of 6 evaluable patients with left-sided active ulcerative colitis at 2 clinical trial sites in Tauranga and Wellington, New Zealand. The participants will be rectally administered with BBT-401 once a day (QD) for 8 weeks. The primary outcome will be assessed via the endoscopic remission rate measured by the Mayo endoscopic subscore and the secondary outcome will be evaluated by the endoscopic response rate defined by the Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score. Other outcome measures will include the clinical remission rate, clinical response rate and the inflammatory bowel disease questionnaire score. Prior to the initiation of the study, the company announced the analysis of the first cohort study in the BBT-401 phase 2a trial. Based on the observed data, the company decided to progress clinical development with a rectal formulation and a further optimized enteric coating of a new oral formulation. The orally administered proof of clinical principle study, which explores the efficacy and safety of BBT-401 at higher doses compared to the low dose study, has been initiated as a multinational study in the U.S., New Zealand, Poland, the Republic of Korea and Ukraine. The interim data of the medium to high dose study is expected to be disclosed in the first half of 2022. BBT-401, an experimental drug discovered by SKKU (Sungkyunkwan University) and KRICT (Korea Research Institute of Chemical Technology), is a GI-tract restricted small molecule Pellino-1 inhibitor. Bridge Biotherapeutics was licensed the worldwide exclusive right to the compound in 2015 and sublicensed the right in 22 Asian countries to Daewoong Pharmaceutical Co. Ltd. in 2018.