Synergistic Effect of Vedolizumab and Pentoxifylline

Inclusion Criteria:

- Patients with active Crohn's disease (CD) defined by blood lab values, stool markers,
abnormal MR enterography imaging, or colonoscopic findings

- Patients who are good candidates to start standard dosing of vedolizumab

- Patients who have not used an off-label or investigational drug for CD in the 8 weeks
prior to screening

- Patients who have met the washout period of 8 weeks for infliximab, 4 weeks for
certolizumab pegol, and 2 weeks for adalimumab if there is a history of anti-TNF
exposure and 8 weeks if there is a history of exposure to natalizumab

- Oral aminosalicylates are allowed during the study, provided that the dose has been
stable for at least 2 weeks prior to screening

- Oral corticosteroids are allowed provided that the dose is prednisone ≤40 mg/day or
equivalent and/or budesonide ≤9mg/day and has been stable for at least 2 weeks prior
to screening

- Patients are able to discontinue thiopurines (azathioprine and 6-mercaptopurine) or
methotrexate upon initiation of vedolizumab

- Rectal therapies, narcotics, anti-diarrheals, probiotics, and antibiotics will be
permitted at investigator discretion

Exclusion Criteria:

- Contraindications or history of allergy to PTX

- Known interaction of PTX with patient's current medications

- Use of an off-label or investigational drug for CD in the 8 weeks prior to first VDZ
infusion

- Pregnancy

- GFR <30 at any time in the 6 months prior to first infusion of VDZ

- Documented cirrhosis

- Age <18 or >80 years old

- Contraindication to colonoscopy at 24 week study time-point