To assess the safety and efficacy of intravenous (IV) PDA001 infused every two weeks for up to 5 total infusions in subjects with Crohn's disease who are refractory to one or more standard Crohn's disease therapies.

This is a randomized, double-blind, placebo-controlled, dose-escalation study to study 3 cohorts of subjects with Crohn's Disease including (but not limited to) those with colonic involvement. Each cohort (n = 9) will include PDA001 treated subjects (n = 6) as well as placebo (vehicle control) treated subjects (n = 3). Cohorts will be enrolled sequentially, beginning with the lowest dose cohort (1/4 unit PDA001) and progressing until the maximum tolerated dose of IV PDA001 is determined.

Inclusion Criteria:

• • Males and females 18 - 75 years of age at the time of signing the informed consent document.

  • Minimum weight of subject is 40 kg at screening.
  • Subject must have inflammatory Crohn's Disease (CD) diagnosed at least 6 months but no greater than 15 years prior to treatment with Investigational Product (IP).
  • Subject must have confirmation of ongoing CD by ileocolonoscopy at screening.
  • Subject must have a Crohn's Disease Activity Index (CDAI) score ≥ 220 and ≤ 450 as assessed between Visit 1 and Visit 2.

Exclusion Criteria:

• Subject has any significant medical condition, laboratory abnormality, or psychiatric illness that would prevent the subject from participating in the study including but not limited to

  • Liver Function Tests Aspartate aminotransferase (AST) or Alanine aminotransferase (ALT) > 2.5 x the upper limit of normal at screening.
  • Serum creatinine concentration > 2.0 mg/dl at screening. Alkaline phosphatase > 2.5 x the upper limit of normal at screening.
  • Bilirubin level > 2 mg/dL (unless subject has known Gilbert's disease).

• Pregnant or lactating females.

• Morbidly obese subjects Body Mass Index (BMI) > 35 at screening).

• Subject has untreated chronic infection including Clostridium difficile toxin positive at screening or treatment of any infection with antibiotics within 4 weeks prior to dosing with IP (other than a treated urinary tract infection or drained perianal abscess). Note: Stable doses of antibiotics used to treat Crohn's Disease are allowed.

• Subject has organic heart disease (eg, congestive heart failure), clinically significant arrhythmia or clinically significant abnormal findings on Electrocardiograms (ECG).

• Subject has a history of other malignancies within 5 years (except basal cell carcinoma of the skin that is surgically cured, remote history of cancer now considered cured or positive Pap smear with subsequent negative follow up).

• Subject has had a stricture of the bowel requiring hospitalization within 182 days prior to treatment with IP.

• Subject has had bowel surgery other than perianal (for example, fistulotomy, seton placement, or abscess drainage) or previous abscess drainage within 182 days prior to treatment with IP.

• Subject has had any surgery within 28 days prior to treatment with IP.

• Subject has a colostomy, ileostomy or ileal pouch anal anastomosis.

• Subject has received an investigational agent -an agent or device not approved by FDA for marketed use in any indication-within 90 days (or 5 half-lives, whichever is longer) prior to treatment with investigational product.

• Subject has received previous cell therapy.

• Subject is expecting to have elective surgery at any time between Visit 1 (screening) and Visit 7 (end of induction phase).

• Subject has concurrent diagnosis of ulcerative colitis.

• Subjects with protein C or S deficiency.

• Subjects with prior history of thrombophlebitis or other pathological arterial or venous thrombosis.