Refractory Functional Dyspepsia (FD) means a state that no symptom was improved in spite of appropriate treatment for the FD.

It may be challenging to discriminate the symptoms of FD from the symptoms of bile dyspepsia resulting from the biliary system. As the bile dyspepsia may induce epigastralgia as with functional dyspepsia and both imaging medical tests and blood tests show normal findings, it is difficult to discriminate it from the FD with only these tests.

Thus this study intends to perform a therapeutic use clinical study for efficacy and safety on symptom improvement by administrating CNU capsule to the patients with RFD.

Functional Dyspepsia means a pain or discomfort of epigastrium originated from the stomach or duodenum without any causative organic or metabolic disease. For its standard criteria, "Rome IV diagnosis criteria" was used, where more than on symptoms including bothersome postprandial fullness, early satiation, epigastric pain, and epigastric soreness should have been elicited at least 6 months before and continued for at least 3 months in total.

Refractory Functional Dyspepsia means a state that no symptom was improved in spite of appropriate treatment for the functional dyspepsia.

The pathogenesis of Functional Dyspepsia has not been fully identified yet. Its standard therapies include prokinetics, analgesics, H2-receptor antagonists, proton pump inhibitors, antacids, serotonin receptor antagonists, proton pump inhibitors, antacids, serotonin receptor antagonists, and antidepressants. As these therapies has lower efficacy and drug related adverse reactions, the RFD patients who do not respond to medication need another therapeutic option.

It may be challenging to discriminate the symptoms of FD from the symptoms of bile dyspepsia resulting from the biliary system. As the bile dyspepsia may induce epigastralgia as with functional dyspepsia and both imaging medical tests and blood tests show normal findings, it is difficult to discriminate it from the FD with only these tests.

Therefore even though the epigastralgia or upper abdominal discomfort met the Rome IV criteria for the FD, the possibility that it, in part was actually resulted from the bile dyspepsia cannot be eliminated.

The CNU capsule is a choleretic used for bile dyspepsia as a complex agent of trihydrated magnesium salt of kenodeoxycholic acid and ursodeoxycholic acid, which are being marketed.

Thus this study intends to perform a therapeutic use clinical study for efficacy and safety on symptom improvement by administrating CNU capsule to the patients with RFD.

Inclusion Criteria:

1. Person over 19 years old as of the date of submission

2. Among patients with FD diagnosed by the Rome IV criteria, patients with RFD

   • Person who have had early satiation and bothersome postprandial fullness for minimum 3 days a week and epigastric pain and epigastric soreness for minimum 1 day a week
   • Person with above symptoms that started at least 6 months before and continused for minimum 3 months
   • Person having no possible causes of above symptoms including organic disease, structural modification, systemic disease, and endocrinology-metabolic disease
   • Person who do not respond to at least 2 general treatments for FD
   • Dyspepsia symptoms that can disrupt daily life (global overall symptom scale score =>5)

3. Persons who submitted written consent to participate in this study

Exclusion Criteria:

1. Patient with biliary disease other than bile stone, scraps in the gall and bile tract, and polyps of gallbladder

2. Patient with structurally abnormal biliary system from congenital malformation or other reasons

3. Patients with endocrinology-metabolic disease that can affect mobility of gastrointestinal tract and biliary system such as diabetes and abnormal thyroid function

4. Patient who cannot discontinue any drug that can provoke abdominal symptoms

5. Patient with disease or damage in central nervous system (cerebral hemorrhage and cerebral infarction with residual disorder) and autonomic nervous system (vertebrate)

6. Patient with renal disorder and electrolyte imbalance

7. Patient who received gastrointestinal surgery (excluding appendectomy and hemorrhoidectomy)

8. Patient with frequent biliary colic or infection of biliary infection

9. Obstructive jaundice patient

10. Severe renal disease patient

11. Patient with variceal bleeding, hepatic coma, ascites, and needs for acute liver transplantation

12. Patient with severe pancreatic disease

13. Person scheduled to receive combined administration of below drugs:

    • Drug with considerable hepatic toxicity Antacid agent containing cholestyramine, medical charcoal, magnesium and aluminum hydroxide
    • alpha-methydopa
    • Drug to increase bile secretion of cholesterol ( estrogen, hormonal contraception agent, partial lipid lowering agent), drug to reduce blood cholesterol

14. Patient with hypersensitivity to this drug or any component of this drug

15. Patient with severe biliary obstruction

16. Patient with radiopaque, calcificated bile stone

17. Patient with acute cholecystitis

18. Patient with peptic ulcer

19. Patient with coloenteritis like Crohn disease

20. Cholestasis patient

21. Patient with abnormality in gallbladder contraction (below 40% of GB ejection fraction)

22. Person relevant to below criteria, as results of tests conducted in screening

    • Person with BUN exceeding 3 times of normal upper limit
    • Person with blood creatinine exceeding 3 times of normal upper limit
    • Person with total bilirubin exceeding 3 times of normal upper limit
    • Person with direct bilirubin exceeding 3 times of normal upper limit
    • Person with AST(sGOT) and ALT(sGPT) exceeding 3 times of normal upper limit
    • Person with ALP(alkaline phosphatase) exceeding 3 times of normal upper limit
    • Person with GGT(gamma-glutamyl transferase) exceeding 3 times of normal upper limit

23. Woman who is pregnant or lactating and women in childbearing age who uses no reliable contraceptive measure or doesn't agree to keep contraception during pregnancy period

24. Person who cannot understand purpose and methods of this study such as mental patients or patients with drug and alcohol abuse

25. Other persons considered by any investigator to have some difficulties in performing this study

The data will become available untill all patients are enrolled and be open to all researchers for 1 year

Only researchers.