Efficacy and safety of Chinese herbal formula CDD-2103 for remission maintenance of ulcerative colitis: Study protocol for a randomized, double-blinded, placebo-controlled trial

Ulcerative colitis (UC) is a chronic lifelong disorder and a prominent subtype of inflammatory bowel disease (IBD) globally. Studies have indicated that Chinese herbal medicines (CHM) may offer advantages in alleviating the clinical symptoms experienced by UC patients. CDD (Centre for Chinese Herbal Medicine Drug Development)-2103 is a CHM formula for maintenance of UC remission. We aim to evaluate its efficacy and safety in remission patients with a traditional Chinese medicine (TCM) pattern of spleen deficiency with dampness obstruction (SDDO). This study is a multi-center, randomized, double-blind, placebo-controlled clinical trial. A total of 82 eligible patients will be randomized to receive either CDD-2103 or placebo for 24 weeks, followed by post-treatment monitoring at week 36 and 48. The primary outcome is the recurrence rate according to the modified Mayo Score at week 24. The secondary outcomes consist of Partial Mayo Score, Inflammatory bowel disease questionnaire (IBDQ), Simple clinical colitis activity index (SCAAI), TCM syndrome scale and safety assessment. This study will provide evidence on the effectiveness and safety of CDD-2103 in reducing chance of clinical relapse for UC patients, and will further shed light on the UC remission maintenance with TCM. Trial registration: Chinese Clinical Trial Registry, ChiCTR2100043200. Registered on 8 February 2021. https://www.chictr.org.cn/showproj.html?proj=121692