Sulfasalazine for the Treatment of Primary Sclerosing Cholangitis

Inclusion Criteria:

1. Age 15-80

2. A diagnosis of PSC for at least 6 months based upon cholangiography (ERCP or MRCP)
demonstrating intrahepatic and/or extrahepatic biliary strictures, beading or
irregularity consistent with PSC.

3. ALP > 1.67 times the upper limit of normal (ULN) at screening

4. Inflammatory bowel disease

5. Subject must either be on a stable dose of ursodeoxycholic acid for > 6 months prior
to screening or have been discontinued > 4 weeks prior to screening (enrollment of
patients who are on UDCA will be limited to 50% of all enrolled patients).

Exclusion Criteria:

1. Anticipated need for liver transplant within one year as determined by Mayo PSC risk
score treatment

2. Evidence of decompensated liver disease such as variceal bleeding, ascites, or hepatic
encephalopathy.

3. Evidence of advanced liver disease including MELD score > 10, bilirubin > 3.0,
platelet count < 100,000; or INR > 1.4

4. Concomitant chronic liver disease including alcohol related liver disease, chronic
hepatitis B or C infection, haemochromatosis, Wilson's disease, alpha1-antitrypsin
deficiency, non-alcoholic steatohepatitis, autoimmune hepatitis, or primary biliary
cholangitis

5. Secondary causes of sclerosing cholangitis

6. Known intolerance to sulfasalazine (including but not limited to allergy to sulfa or
mesalamine) or folic acid

7. History of cholangiocarcinoma or colon cancer within 5 years

8. History of colectomy with > 1/3 bowel resected

9. Treatment with any investigational agents, within two months or 5 half-lives of the
investigational product, whichever is longer.

10. Active illicit drug or alcohol abuse

11. Current or past use of sulfasalazine within 6 months of enrollment.

12. Treatment with antibiotics within 3 months of start of medication

13. Need for chronic use of antibiotics

14. Evidence of bacterial cholangitis within 6 months of enrollment

15. In patients with Ulcerative Colitis, simple clinical colitis activity index of > 4 or,
if Crohn's disease, a Harvey-Bradshaw index of > 5

16. Chronic kidney injury (eGFR < 59)

17. Pregnancy or lactation