This study is for individuals who have Crohn’s disease (CD). The purpose of this research study is to compare the effects of the study drugs, PF-06651600 and PF-06700841, with a placebo (a preparation made to look like the study drug but that has no activity, like a sugar pill) to find out if PF-06651600 and PF-06700841 may be effective for treating CD.

PF-06651600 and PF-06700841 are investigational drugs. An investigational drug is one that is not approved for sale in this country. You may be in this research study for about 74 weeks. You will need to visit the research site at least 15 times (including the first screening visit) during the study. The study doctor may schedule visits (unplanned visits) in addition to those listed on the schedule of activities, in order to conduct evaluations or assessments to protect your well-being.

Inclusion Criteria:

1. Documented diagnosis of ileal, ileocolonic, or colonic CD with a minimum disease duration of 3 months, as determined by endoscopic and histopathology assessment.
2. Endoscopic confirmation of active disease with total SES CD total score of at least 7. For isolated ileal disease, SES CD total score should be at least 4.
3. An average daily liquid/soft stool frequency (SF) greater than or equal to 2.5 or daily abdominal pain (AP) greater than or equal to 2.0.

4. Must have inadequate response to, loss of response to, or intolerance to at least one conventional therapy for CD:

   •Steroids; Immunosuppressants (azathioprine [AZA], 6 MP, or methotrexate [MTX]); Anti TNF inhibitors (infliximab, adalimumab,certolizumab); Anti integrin inhibitors (eg, vedolizumab); Anti IL 12/23 inhibitor (ustekinumab).

5. Subjects currently receiving the following treatment for CD are eligible providing they have been on stable doses as described below:

   • Oral corticosteroids (prednisone or equivalent up to 25 mg/day; budesonide up to 9 mg/day). Stable dose for at least 2 weeks prior to baseline. If oral corticosteroids have been recently discontinued, they must have been stopped at least 2 weeks prior to baseline. Decreases in steroid use due to AEs are allowed.
   • Oral 5 ASA or sulfasalazine are allowed providing that the dose is stable for at least 4 weeks prior to baseline.
   • Crohn's disease related antibiotics are allowed providing that the dose is stable for at least 4 weeks prior to baseline. If antibiotics are stopped prior to baseline, they must be discontinued at least 4 days prior to baseline.

Exclusion Criteria:

1. Diagnosis of indeterminate colitis, microscopic colitis, ischemic colitis, infectious colitis, radiation colitis, diverticular disease, ulcerative colitis (UC), or clinical findings suggestive of UC.
2. Presence of active (draining) fistulae or intra abdominal or perineal abscesses.
3. Strictures with obstructive symptoms.
4. Short bowel syndrome.
5. History of bowel perforation requiring surgical intervention within the past 12 months.
6. Previous bowel surgery resulting in an existing stoma. Subjects who have a j pouch are excluded, as a j pouch can result in a stoma.
7. History of bowel surgery within 6 months prior to baseline.
8. Subjects displaying clinical signs of fulminant colitis or toxic megacolon.
9. Subjects with primary sclerosing cholangitis.
10. Subjects with evidence of colonic adenomas, dysplasia or neoplasia.
11. Abnormal findings on the chest x ray film such as presence of tuberculosis (TB), general infections, heart failure, or malignancy.
12. Any history of either untreated or inadequately treated latent or active TB infection, current treatment for active or latent TB infection or evidence of currently active TB 
13. Subjects with history of thrombotic event(s), including deep venous thrombosis (DVT), and known inherited conditions that predispose to hypercoagulability.