Clinical Trials of N-acetyl Glucosamine Capsule for IBS-D Treatment

This study is a randomized double-blind placebo-controlled clinical trail to evaluate the clinical efficacy and safety of 1.1 chemical drugs N-acetyl-D-glucosamine on Chinese IBS-D patients coming from thirty- six centers in Chinese. 720 IBS-D patients (360 for treatment group, 360 for placebo group) in this research are accord with the Rome III diagnostic criteria, screening/import period pain intensity scores of the NRS(numerical rating scale) week mean value are 3.0 plus and the days which at least more than one time a stool type are 6 or 7 type over 2 days/week. Test cycle includes screening/import period (2 weeks), open treatment period (12 weeks), follow-up period (2 weeks). The main outcome measures are pain intensity (NRS score 11 point scale) and stool type ( Bristol type), and secondary endpoints included overall symptoms sensory scores, defecation frequency, abdominal distension, defecation urgency and quality of life parameters (IBS-QOL scale).


Eligibility Criteria:
Inclusion Criteria:

* Voluntarily signed the informed consent form.
* Man or woman, aged 18 to 65 years, inclusive.
* Based on the Roman III diagnostic criteria for diagnosis of IBS-D subjects, recurrent abdominal pain accompanied with abdominal discomfort or not, monthly attack within the past 3months at least 3 days. With two or more of the following three kinds of symptoms:

At least a portion of the time abdominal pain or defecate increase when discomfort.

At least a portion of the time abdominal pain or the row of loose stools when discomfort.

At least a portion of the time abdominal pain or discomfort improved after defecation.

Symptoms for at least 6 months before diagnosis.

* Screening/import period pain intensity scores of the NRS week mean value are 3.0 plus and the days which at least more than one time a stool type are 6 or 7 type over 2 days per week.
* During the screening period，patients should answer the questions of electronic log completely following the requirements for 10days or more.
* Patients are willing to stop drugs for abdominal symptoms or diarrhea which are in violation of the scheme, and take medicine prescribed in the scheme.
* Patients agree to not change the lifestyle significantly that may affect the symptoms of IBS-D from signing up the Informed Consent Form to the last experiment.
* The illness recured after a normal colonoscopy report within one year that was provided by this hospital or a grade first class teaching hospital, include polyp of colon (less than 3mm,the number of less than 5) patients who taked therapeutic endoscopy and recurrenced within one year; or those that get a normal colonoscopy report in this hospital or a grade first class teaching hospital before screening but have a history of bowel preparation, should be chosen when next attack.

Exclusion Criteria:

* History of organic gastrointestinal diseases: Chronic pancreatitis (cp), inflammatory bowel disease, intestinal tuberculosis, malabsorption syndrome, celiac disease, gastrointestinal tumor, or other organic diseases etc.
* History of abdominal and pelvic surgery ( not including appendectomy and intestinal polyposis (\<3mm) after treatment within one year ).
* The non-intestinal disease of digestive system such as Peptic ulcer, tuberculous peritonitis, cirrhosis etc.
* Heart, lung, kidney and other important organs have severe lesions, immune regulatory disease, metabolic disease (diabetes, thyroid disease) or malignant tumor, reproductive system diseases such as ovarian cysts, endometriosis, etc.
* Laboratory tests or Electrocardiogram were significantly abnormal, and judging by the researchers may damage the patient safety or successful completion of the clinical research:

Male hemoglobin \<120g/L, female hemoglobin \<100g/L;

Male serum creatinine≥133umol/L, female serum creatinine≥124umol/L; or creatinine clearance rate≤60ml/min;

Chronic liver disease and/or abnormal liver function, defined as AST (aspartate aminotransferase) \> 1.5 x ULN (Upper Limit Of Normal) and/or ALT (alanine aminotransferase) \> 1.5 x ULN and/or total bilirubin \> 1.5x ULN;

* Serious psychiatric patients( Hamilton Depression Scale scores\>20).
* History of drug abuse or alcohol abuse.
* Allergic to this study drug.
* Concomitant medication is unable to stop or use continuously for more than a week but affect the gastrointestinal movement and function in the experiment, such as antibiotic drugs, the drugs of regulating the intestinal microecology, parasympathetic inhibitors, muscle relaxants, antidiarrheal, opiates, etc.
* Do not fill in the electronic log of one week before entering the group (-1 week) completely.
* Pregnant or lactating women
* Is participating in clinical trials or have finished it less than 3 months.
* Other researchers think not suitable for the list.