The study is a multi-center, randomized, double-blind, placebo controlled clinical trial. Totally, all participants will have 5 visits at week 0, 2, 6, 10, and week18, respectively. At week 0, the first screening will be conducted to include potential participants. Week 0 to week 2 belongs to run-in period. At week 2, the second visit will be conducted to assess the baseline of participants. Then, those eligible participants will be randomized in 1:1 ratio to receive either JCM-16021 or placebo. At week 6, the third visit will be conducted to assess the situation after treatment of four weeks. At week 10, the fourth visit will be conducted to assess the situation after treatment of eight weeks. Then these participants will be followed up with another eight-week and the fifth visit will be conducted at week 18. In total, the whole study will last for 18 weeks, including two weeks of the run-in period, eight weeks of the treatment period, and eight weeks of the follow-up period. All visits will be conducted at the designated clinics face to face. The flowchart and schedule of the trial are shown in Figure 1 & Figure 2, including schedule of enrolment, interventions and assessments. The trial protocol is written in accordance with Standard Protocol Items for Clinical Trials with Traditional Chinese Medicine 2018: Recommendations, Explanation and Elaboration (SPIRIT-TCM Extension 2018) checklist14 (Supplementary 1). And the structured study summary is described in Table 1 according to the World Health Organization Trial Registration Data Set.
Setting of the study
The study will be conducted in three centers simultaneously as follows: 1) Hong Kong Baptist University Mr. & Mrs. Chan Hon Yin Chinese Medicine Specialty Clinic and Good Clinical Practice Centre, 2) Hong Kong Baptist University HK Island Wei Ke Qiang Chinese Medicine Specialty Clinic, 3) Center for Integrative Medicine, Hong Kong Institute of Integrative Medicine, The Chinese University of Hong Kong.
Randomization
The randomization sequence for the intervention of the 392 participants will be generated using block randomization with a fixed block size by our statistician with SPSS statistical analysis software. The sequence will be kept in opaque sealed envelopes with consecutive numbers. These envelopes will be prepared by pharmaceutical company. The envelopes numbered 001-100 and 201-392 will be kept at the site of Hong Kong Baptist University. The envelopes numbered 101-200 will be kept at the site of the Chinese University of Hong Kong. These envelopes will be blinded to Chinese Medicine Practitioners who will be responsible for the recruitment and evaluation. Each center will have a research assistant responsible for allocating drugs to participants. The research assistant will open the same numbered envelope based on the randomization enrolment number when an eligible participant can be included in the trial. Then, the research assistant will assign the drugs to the participant according to the sequence. 392 eligible participants will be randomized and assigned to the JCM-16021 group or the placebo group in 1:1 ratio (196 cases/group).
Blinding
The trial is a double-blinded design, in which all the Chinese Medicine Practitioners, research assistants and participants are ignorant of the treatment assignments. The physical appearance of placebo is consistent with JCM-16021, including the packaging, appearance, color and taste. pharmaceutical company will be responsible for labelling JCM-16021 and placebo according to the blinding codes. '16021A' and '16021B' will be used to label the interventions. The blinding code will be kept strictly confidential by the principal investigators until completion of the final statistical analysis and report of the trial. If there is a serious adverse event (SAE) relevant to the research medication, the assignment code will be broken. The date and reason for breaking the blinding code should be recorded in the Case Report Form (CRF). Relevant institutions, including the Research Ethics Committee and Department of Health of HKSAR should be informed accordingly within 24 hours.
Recruitment
The recruitment of the study is via the press conference, announcement on university website, advertisement on local newspaper or Facebook, promotion posters and leaflets, and specialist’s referral. People who are interested in the trial can contact the researchers by telephone and e-mail. Researchers will conduct preliminary screening on the phone and invite these potential candidates to come to the clinics to have a further screening face to face. Chinese Medicine practitioners will be responsible for conducting the screening and explain the details of the study, such as content, arrangement, and possible risks etc. The eligible participants will be invited join the study after signing the informed consent form.
Diagnostic criteria
According to Rome IV Criteria, IBS is diagnosed based on: recurrent abdominal pain, on average, at least one day per week in the last three months and associated with any two or more of followings: i) related to defecation, ii) change in frequency of stool, or iii) change in form (appearance) of stool. Meanwhile, diarrhea predominant is classified by loose (mushy) or watery stools > 25% and hard or lumpy stool <25% of bowel movements22.
The diagnostic criteria of LSSD pattern of TCM is in reference to the “Guiding Principles for Clinical Study of New Chinese Medicines”23. LSSD is diagnosed when all the main symptoms and signs and associating with two or more secondary symptoms and signs are fulfilled. The main symptoms and signs include: i) abdominal pain and diarrhea (inducing or aggravating by emotional upset or stress), and ii) changes with defecation. Secondary symptoms and signs include: i) borborygmus and passing gas frequently, ii) distention and fullness in chest and hypochondrium, and frequent sighing, 3) emotional depression or irritability, 4) anorexia and abdominal bloating, and 5) pale red tongue with white thin fur and string like pulse.
Inclusion criteria
Participants will be included if they fulfill all of the following: 1) the diagnosis criteria of IBS-D based on Rome IV criteria; 2) the diagnosis of LSSD pattern of TCM based on “Guiding Principles for Clinical Study of New Chinese Medicines”; 3) Age of 18 to 65 years; 4) with written informed consent.
Exclusion criteria
Participants will be excluded if they have one or more of the following: 1) Constipation predominant, mixed or unsubtyped IBS; 2) Abnormal colonoscopy within five years (except for benign polypectomy or hemorrhoids); 3) With severe diseases on the system of heart, lung, liver, and kidney which are diagnosed by TCM theory; 4)Concomitant diabetes, Glucose-6-Phosphate Dehydrogenase deficiency, unstable hypertension, malignant tumor or have undergone thyroid surgery or medication within a year; 5) With diseases on the Spleen-Stomach system or other diseases that affect the movement of qi on the Spleen-Stomach system, which are diagnosed by TCM theory; 6) Current concomitant medication with effects on gastrointestinal function (e.g. anticholinergic drugs, calcium channel blockers, 5-HT3 receptor antagonists, antidiarrheal agents, antacids, prokinetic agents, antidepressants, anxiolytics and intestinal flora regulating drugs); 7) Medical history of gastrointestinal surgery (except for appendicitis surgery); 8) The serum levels of alanine transaminase (ALT), aspartate transaminase (AST), and creatinine (Cr) exceed 1.5 times of the reference limit; 9) History of allergy in Chinese medicine; 10) Women in pregnancy or breast-feeding; 11) Medical history of neurological diseases or psychiatric disorders; 12) Currently participating in another clinical trial; 13) Taking IBS treatment drugs within 1 week.
Drop out criteria
During the study, participants may opt to withdraw at any time. Those who are lost to follow up or withdraw from the study after randomization will be treated as drop-out cases.
Experimental group
Participants assigned to the experimental group will take JCM-16021 granules (8g/sachet) orally, one sachet each time, three times daily for 8 weeks. According to the original ratio of the JCM-16021 formula, JCM-16021 Granules are processed from seven raw Chinese medicine herbs by a modern technique by the Purapharm (Nanning) Pharmaceutical Co.Ltd. The original JCM-16021 formula is composed of seven herbs as follows: Rhizoma Atractylodis Macrocephalae (Baizhu) 20g, Radix Paeoniae Lactiflorae (Baishao) 15g, Cortex Magnoliae Officinalis (Houpo) 10g, Semen coicis Lachryma-jobi (Yiyiren) 20g, Polygonaceae (Huotanmu) 20g, Fructus Terminaliae Chebulae(Hezi) 10g, Rhizoma Corydalis Yanhusuo (Yanhusuo) 15g. The produced JCM-16021 granules will be packaged in a sachet of 8 grams with Aluminum foil composite film. And then the packaged JCM-16021 granules will be packed in a bigger transparent bag with a label. Every bag contains 21 sachets of JCM-16021 granules. For better guaranteeing the safety and quality of the JCM-16021 granules, accelerated stability tests, heavy mental and toxic elements, pesticides residues, and microbial limit will be conducted.
Control group
Participants assigned to the control group will take placebo granules (8g/sachet) orally, one sachet each time, three times daily for eight weeks. The placebo is made from Caramel (0.55%), Sunset Yellow (0.01%), Tartrazine (0.06%), Gardenia Yellow (0.06%), Aspartame (0.8%), Sucrose Octaacetate (0.02%), Starch (49.25%), and Dextrin (49.25%).The form, color, package, usage, and dosage of placebo is consistent with JCM-16021 granules, as is shown in Supplementary 2.
Quality of Investigational Medicinal product
All investigational medicinal product (IMP) including the JCM-16021 granules and placebo are produced by the Purapharm (Nanning) Pharmaceutical Co. Ltd. The entire manufacturing process will be in strict compliance with the standards of Good Manufactory Practice (GMP). The production process of the JCM-16021 granules and placebo granules will be compliant with the quality specification standards, respectively. According to the Chinese Pharmacopoeia (2015), all qualified IMP will be delivered to the site of clinical study and stored within a range of 25°C±2°C and relative humidity range of 60%±10%24. The investigators are responsible for ensuring adequate accountability of all used and unused IMP.
Primary outcome
The primary outcome is the improvement rate on the Global Assessment of Improvement (GAI) score at week 10, same as the previous small scale study16. The participants will be asked to give a global assessment of their IBS symptoms at visit 3, 4 and 5 with the question “In the past 7 days, compared with your IBS symptoms before you started the trial, are you now: substantially worse, moderately worse, slightly worse, no change, slightly improved, moderately improved, or substantially improved? 25’’ The global symptom improvement will be evaluated by scales (substantially worse=0, moderately worse =1, slightly worse=2, no change=3, slightly improved=4, moderately improved=5, substantially improved=6). The 0-2 score, 3 score and 4-6 score represent worsen, no change and improvement, respectively.
Secondary outcomes
IBS symptoms
IBS symptoms, including abdominal pain (with scores from 0 to 10 representing none to most severe), stool frequency and stool consistency will be recorded by participants in a diary throughout 18 weeks of study. Investigators will grade each symptom by Cardinal symptoms evaluation quantitation scale (None=0, Mild=1, Moderate=2, Severe=3) shown in Table 1 in Supplementary 3. The changes of these IBS symptoms before and after the treatment will be used for efficacy evaluation. The details are as below:
i)Pain Responder Rate In Daily Worst Abdominal Pain Scores: According to the guidance of the U.S. FDA, pain responder is defined as that participant who meets the daily pain response criteria for at least 50% of the days with diary entries during the observational period of interest. Daily pain response is defined as the ≥ 30% decrease in the worst abdominal pain scores in the past 24 hours compared to baseline (average of daily worst abdominal pain the 2-week prior to randomization). Pain score is ranked from 0 to 10 representing none to the most severe26.
ii) Stool consistency Responder Rate In Daily Stool Consistency Scores: Stool consistency responder is defined as that participant who meets daily stool consistency response criterion (ie, score of 1, 2, 3, or 4 or absence of bowel movement if accompanied by ≥30% decrease in worst abdominal pain scores compared to baseline pain) for at least 50% of days with diary entries during the observational period of interest. Bristol stool scale is defined as 7-point Scale in which a score of 1 = separate hard lumps, 2 = sausage shaped but lumpy, 3 = sausage-like with cracks on the surface, 4 = sausage-like but smooth and soft, 5 = soft blobs with clear cut edges, 6 = fluffy pieces with ragged edges, and 7 = watery with no solid pieces26.
iii) Improvement Rate and Efficacy Rate: The standards of efficacy assessment of single symptom are as follows: a) Excellent: symptoms disappearing; b) Effective: symptom score decreased ≥2 points; c) Helpful: symptom score decreased 1 point; d) Invalid: no change in symptom score. Improvement rate is defined as the proportion of participants in excellent, effective and helpful. Comprehensive efficacy judgement standard of cardinal symptoms is calculated by “(total scoring of prior treatment – total scoring of post treatment) / total scoring of prior treatment x 100%”. Clinical remission is defined as symptom disappearing, Symptom improvement (≥80%), Helpful (between 50% and 80%), Invalid (<50%). Total effective rate is defined as the proportion of participants with clinical remission and symptom improvement23.
TCM pattern
Five typical symptoms for LSSD are assessed to evaluate the changes of TCM Pattern, involving i) abdominal distension, ii) borborygmus and flatus, iii) distension and fullness in chest and hypochondrium, iv) frequent sighing, poor appetite, and v) mental depression or irritability. Investigators will grade the TCM pattern scale (None=0, Mild=1, Moderate=2, Severe=3) as shown in Table 2 in Supplementary 3. Efficacy assessment standards of Syndrome of Chinese medicine are as follows: Clinical remission: clinical symptoms and signs disappear or basically disappear, total scoring declining ≥95%; Excellence: clinical symptoms and signs are significantly improved, total scoring declining ≥ 70%; Effective: clinical symptoms and signs are improved, total scoring declining ≥ 30%; Invalid: clinical symptoms and signs are without obvious improvement or even with exacerbation, total scoring declining < 30%. The effective rate on TCM pattern will be evaluated with following calculation formula (nimodipine method): [(total score of prior treatment – total score of post treatment) / total score of prior treatment]×100%23.
Irritable Bowel Syndrome-Quality of Life
Participants who are enrolled will fill in the Irritable Bowel Syndrome-Quality of Life (IBS-QoL) questionnaire during the study. IBS-QoL includes 34 items and involves 8 aspects: dysphoria (Q1), interference with activity (Q2), body image (Q3), health worry (Q4), food avoidance (Q5), social reaction (Q6), sexual (Q7) and relationship (Q8) 27. Each item will be rated on a 5-point Likert scale. Higher score reflects better quality of life. The difference of score before and after the medication will be evaluated.
Irritable Bowel Syndromes-Symptom Severity Score
The Irritable Bowel Syndromes-Symptom Severity (IBS-SSS) Score questionnaire will be completed at visit 2, 3, 4, 5. The IBS-SSS involves five aspects: the severity of abdominal pain, the frequency of abdominal pain, the severity of abdominal discomfort, defecation satisfaction, and interference with daily life. The range of score is 0-500 points scale28. The change of score before and after the medication will be evaluated.
Safety outcome
In this study, adverse events (AEs) or serious adverse events (SAEs) related to Investigational medicinal products (IMP) are used for safety evaluation, including new incurrence symptoms or diseases, abnormal vital signs, clinically significant abnormal laboratory examination. The severity of AEs are graded based on the Common Terminology Criteria for Adverse Events v4.0.
Quality control and assurance
Firstly, all investigators will be required to complete the TRREE on-line training programme on the ethics and regulation of health research involving human participants (https://elearning.trree.org/) and get the online certification of Good Clinical Practice (GCP) before the start of the study. Secondly, all investigators will be arranged to study the details of the protocol and investigator’s brochure together at the research centre of Hong Kong Baptist University. If there are some modifications, investigator will also study the revision of the protocol and the investigator's brochure in time. Thirdly, a regular monthly meeting will be held to report the study progress (either recruitment, compliance or adverse events etc.) to principal investigators, assess the investigators’ activities (either data collection, data entry, or compliance with the protocol and investigator’s brochure etc.), discuss and solve the problems (if any). In general, the meeting will be conducted at the office of Hong Kong Baptist University.
In addition, investigators are required to explain details of clinical trial to participants and obtain informed consent. Investigators should also let participants be fully informed of the significance of trial and importance of medication on time. For participants with low compliance, investigators should follow the participant in time and record the reasons in details. Every study site needs to strictly master the standard of quality control individually and implement strict pharmaceutical administration.
Data collection, management and monitoring
All data will be collected through patient diaries, questionnaires, and CRFs. All enrolled participants have to record their abdominal pain, stool frequency, stool consistency in a paper-based patient diary throughout 18 weeks of study. At each visit, participants will be required to return the diaries and complete some questionnaires, including the GAI questionnaire, the IBS-QoL questionnaire, and the IBS-SSS questionnaire. Chinese Medicine Practitioners and study coordinators have to fill in the CRFs to record relevant information, such as the blood pressure, the changes of TCM Pattern, and compliance/noncompliance with research medication and concomitant conventional maintenance therapy etc. These data collected in visit 2 will be the baseline data. All personal information of participants will be kept confidential. The Research Electronic Data Capture (REDCap) 29, 30 will be used to collect and manage all participants’ data by researchers. All centers have corresponding personnel to input the data timely. The researchers with authorized accounts can log in and browse the data. All raw data collected by patient diaries, questionnaires, and CRFs could be shared based on the request and special approval from the team. During the whole study, all AEs (new incurrence symptoms or diseases, abnormal vital signs, clinically significant abnormal laboratory examination) should be recorded in CRF and investigators are also required to fill in the relevant information in the “Adverse Event Report Form”, which include start time, duration, severity, and relationship with IMP etc. Once there is an adverse event which results in hypersensitivity towards research medication or significant abnormality on liver or renal function, investigators can require participants to stop IMP and report it to principal investigators in time. If there are any SAEs, investigators should fill in the “Serious Adverse Event Report Form” with signature and report to the Research Ethics Committee within 24 hours. Also, all AEs and SAEs are required to be reported to Department of Health of HKSAR every year. The trial document will be kept for 7 years after the completion of the trial. Research Ethics Committee and Department of Health play a role to monitor the data. The principal investigators need to submit the progress reports to the Research Ethics Committee and the Department of Health every year, and to the funding agency Innovative Technology Commission (ITC) of the government of Hong Kong Special Administrative Region (HKSAR) every 6 months.
Biological specimen collections
During the clinical study, the blood, urine and feces will be collected from all participants with written informed consent on 2nd and 10th week, respectively. All samples will be delivered to the lab of the School of Chinese Medicine, Hong Kong Baptist University and be stored at -80°C for the metabolomics and metagenomics sequencing analysis. Blood, urine and fecal samples will be collected to analyze the metabolites profile of gut microbiota and the host before and after the treatment. Metagenomics sequencing will be used to monitor the gut microbiota composition profile before and after treatment. Both metabolomics and metagenomics sequencing are served as the methods to explore the mechanism of JCM-16021 attenuating the bowel symptoms by modulating gut microbiota.
Sample size calculation
From our previous study, improvement rate on the Global Assessment of Improvement was 52% in JCM-16021 group and 32% in western medicine group, respectively 18. According to the previous clinical trial guidelines for pharmacological treatment of irritable bowel syndrome, a 15% improvement of the global outcome measure over placebo could be considered as a clinically significant therapeutic gain31. We assumed that there would be a 15% difference in the proportion of participants who report an improvement in their global symptoms after eight weeks of treatment (either slight, moderate, or substantial) between the placebo group and the JCM-16021 group. Thus, 166 participants are required in each group with 80% power and two-sided 5% alpha. Further assuming a 15% drop-out rate, a total of 392 participants (196 per arm) will be enrolled to ensure that the study is sufficiently powered to answer the research question of interest.
Statistical analysis
Baseline data will be descriptively summarized. Categorical variables will be summarized by frequencies and percentages. Continuous variables will be summarized with mean and standard deviation [Mean±SD].
For the outcome analysis, Comparisons between two groups for continuous variables will be conducted by using an analysis of variance (ANOVA), with other confounding factors like a multicenter character conducting the covariate analysis. Statistical analysis for the data which do not meet above conditions (e.g. non-normal) will be conducted with the use of non-parametric test. Categorical data of different groups will be reported as frequency (proportion). Comparisons between groups for these categorical data will be assessed with the use of chi-square test (CMH test) or non-parametric testing. For the repeatedly measured outcomes, the difference with the baseline data (follow-up minus the baseline) will be analyzed and the baseline data will be included in the model as covariables. Subgroup analyses will be carried out irrespective of whether there is a significant treatment effect on the primary outcome. The participants’ drop-out will be descriptively summarized. Both per-protocol analysis (PP) and intention-to treat (ITT) analysis will be used to conduct the efficacy analysis. All treatment groups’ comparisons except for the primary outcome will be performed at a two-sided level of 0.05.
The safety analysis will mainly be performed by analysis of the incidence of adverse events between groups and the incidence of abnormal laboratory data before and after treatment between groups. A detailed description of the statistical analysis plan (SAP) is provided in supplementary 3.