Phase 3 Study of Human TH-SC01 Cell Injection for Treating Perianal Fistulas in Patients With Crohn's Disease

Prior treatment

• Rectal and/or anal stenosis , if this means a limitation for any surgical procedure
• Subjects with concurrent active proctitis.
• Patients have undergone a diverting stoma operation in the past, except for patients have completed stoma closure at least one month before drug administration.
• Subjects received stem cell treatment within two years prior to screening.
• Patient with ongoing steroid treatment or treated with steroids in the last 4 weeks.
• Patient undergone major surgical operations (such as orthopedic surgery, abdominal surgery) within one month before drug administration, or Patient plan to receive surgeries during the study period (except for the surgeries required by the procedures of this trial).
• Patients with a history of diverting ostomy, except those who have undergone stoma reversal at least 1 month prior to drug administration.

Other illness

• Subjects with active infection evaluated by the investigator
• Subjects with active Crohn's disease before drug administration or have not completed the induction-phase treatment.
• Patients plan to undergo surgery in the perianal area during the trial period due to other diseases other than anal fistula.
• Subjects with malignant tumors or a history of malignant tumors.
• Current or recent history of abnormal, severe, progressive, uncontrolled hepatic, haematological, gastrointestinal (except CD), endocrine, pulmonary, cardiac, neurological, psychiatric, or cerebral disease.
• Patients with a history of drug abuse or alcoholism (Criteria for alcoholism: having a long-term drinking history of more than 5 years, with the amount of ethanol equivalent to ≥40g/d for men and ≥20g/d for women, or having a history of heavy drinking within 2 weeks, with the amount of ethanol equivalent to \>80g/d. The conversion formula for the amount of ethanol (g) = the amount of alcohol consumed (ml) × the ethanol content (%) × 0.8).
• Other diseases or conditions that the investigator deems inappropriate for participating in this clinical trial, such as poor subject compliance and the expectation of being unable to complete follow-up and evaluation.

Lab values

• Subjects allergic to human serum albumin, human platelet lysate, gentamicin sulfate, anesthetic drugs or MRI contrast agents.
• Subjects with abnormal laboratory results: liver function: total bilirubin \>=1.5 × ULN, and aspartate aminotransferase (AST) and alanine aminotransferase (ALT) \>=2 × ULN; renal function: creatinine clearance below 60 mL/minute calculated using Cockcroft-Gault formula or by serum creatinine \>=1.5 × upper limit of normal (ULN).
• Serum virology test (HBeAg, HCV antibody, HIV antibody, Treponema pallidum antibody) positive.

Other

• Subjects with abscess or collections \>2 cm.
• Subjects with other fistulas such as rectum/anal canal-vaginal fistulas or rectum-bladder fistulas.
• Subjects with congenital or acquired immunodeficiency.
• Contraindication to MRI scan
• Pregnant or lactating women.

• Signed informed consent
• Subjects with Crohn's disease diagnosed at least 6 months earlier according to the Chinese Consensus Opinion on the Diagnosis and Treatment of Inflammatory Bowel Diseases (Beijing, 2018)
• Subjects with active perianal fistula and non active luminal CD defined by a CDAI ≤ 200.
• Presence of perianal fistulas with a maximum of 2 fistulas (internal openings) and a maximum of 3 external openings, assessed by clinical assessment and MRI.
• Eastern Cooperative Oncology Group (ECOG) performance status score of 0 to 1.
• American Society of Anesthesiologists (ASA) physical status classification of grade I to grade II.
• All subjects and their partners were not planning to have a child from screening to the end of the trial and agreed to use effective non-drug contraception during the trial.