Design and Investigation:
Number of Patients: 5 (including a consideration of 20% [1 patient] dropout from the trial)
Dosage and mode of administration Dosage: A total of 60 million PF2020-CELL (UC-MSCs) will be injected locally around the fistula tract, with a separation of 1 cm between injections. All patients will receive a total of 60 million cells per visit for 5 visits, with a 6 - 12 weeks interval between the injections. If the patient is completely healed during any course of stem cell injections, subsequent stem cell treatments can be discontinued. However, patients will still be required to undergo regular follow-up examinations, including physical examinations and other medical tests, until the study is completed.
Mode of administration: The procedure involves localizing the fistulous tract, performing curettage and closing the internal opening, and the injection of PF2020-CELL (UC-MSCs). The indicated dose of PF2020-CELL (UC-MSCs) will be injected starting from the tissues around the internal orifice or orifices and then progressing towards the external opening.