for people ages 18-70 (full criteria)
at San Francisco, California
study started
estimated completion
Principal Investigator
by Sandy Feng
Headshot of Sandy Feng
Sandy Feng



This is a single-center, prospective, open-label, non-randomized clinical trial exploring cellular therapy to facilitate immunosuppression withdrawal in liver transplant recipients.

Official Title

A Phase I/II Drug Withdrawal Study of Alloantigen-Specific Tregs in Liver Transplantation


The researchers in this study plan to enroll 9 participants. Eligible participants will receive a single dose of Treg product (arTreg). The target dose is at least 90 x 106 total cells. Participants who successfully withdraw from all immunosuppression (IS) will undergo a research biopsy at 52 weeks following IS discontinuation to determine whether they meet the primary efficacy outcome of operational tolerance. Participants determined to be operationally tolerant will be followed until 104 weeks following IS discontinuation. Participants who fail drug withdrawal after 52 weeks but before 104 weeks will be followed until week 104 or 12 weeks after resuming immunosuppression, whichever is longer. Participants who do not successfully withdraw from all IS will complete 104 weeks of High Intensity Safety Follow-up after failing immunosuppression withdrawal. IMPORTANT NOTICE: The National Institute of Allergy and Infectious Diseases and the Immune Tolerance Network do not recommend the discontinuation of immunosuppressive therapy for recipients of cell, organ, or tissue transplants outside of physician-directed, controlled clinical studies. Discontinuation of prescribed immunosuppressive therapy can result in serious health consequences and should only be performed in certain rare circumstances, upon the recommendation and with the guidance of your health care provider.


Liver Transplant, alloantigen-reactive Tregs (arTreg), immunosuppression, operational tolerance, Cyclophosphamide, Everolimus, arTreg, leukapheresis, mesna


You can join if…

Open to people ages 18-70



  • Individuals must meet all of the following criteria to be eligible for this study:
  • Able to understand and provide informed consent
  • End-stage liver disease and listed for a living or deceased-donor primary solitary liver transplant
  • Agreement to use contraception
  • For candidates with a history of hepatitis C virus (HCV), completed treatment for HCV, maintaining a sustained viral response of ≥24 weeks duration by the day of transplant
  • Positive Epstein-Barr virus (EBV) antibody test, and
  • Immunizations are up-to-date based on the Advisory Committee on Immunization Practices (ACIP) recommendations for individuals with Liver Disease and Adult Vaccination, unless the investigator determines that administering a recommended immunization is not in the patient's best interest.

Living Donor:

  • Living donors must meet all of the following criteria to be eligible for this study:
  • Able to understand and provide informed consent
  • Meets site-specific clinical donor eligibility requirements
  • Meets donor eligibility manufacturing requirements within 7 days before or after the blood collection for manufacturing, and
  • Willingness to donate appropriate biologic samples.

Deceased Donor:

Deceased donors must meet the following criteria for their recipients to remain eligible:

  1. Meets site-specific clinical donor eligibility requirements and
  2. Meets donor eligibility manufacturing requirements.


  • There are several stages to this study.
  • Eligibility is evaluated at many time points during the study to assess whether a participant is safe to proceed to the next study stage.

You CAN'T join if...


  • Individuals who meet any of the following criteria will not be eligible for this study:
  • History of previous organ, tissue or cell transplant
  • For cytomegalovirus (CMV) antibody negative recipients, a (CMV) antibody positive donor
  • Known contraindication to cyclophosphamide or mesna
  • Serologic evidence of human immunodeficiency virus (HIV)-1/2 infection
  • The need for chronic anti-coagulation or anti-platelet agents other than aspirin that cannot be safely discontinued for a minimum of 1 week to safely perform a liver biopsy
  • End stage liver disease secondary to autoimmune etiology (autoimmune hepatitis, primary biliary cirrhosis, or primary sclerosing cholangitis) or other contraindications to drug withdrawal
  • Psychological, familial, sociological or geographical factors potentially hampering compliance with the study protocol and follow-up visit schedule
  • Any condition that, in the opinion of the investigator, may interfere with study compliance
  • History of cardiac disease (ischemic heart disease requiring revascularization, history of or current treatment for dysrhythmia, or evidence of congestive heart failure), unless cleared by a cardiologist
  • . Any past or current medical problems, treatments or findings that are not listed above, which, in the opinion of the investigator, may:
  • pose additional risks from participation in the study,
  • interfere with the candidate's ability to comply with study requirements, or
  • impact the quality or interpretation of the data obtained from the study
  • This includes past, present or future enrollment in studies that affect eligibility at the time of everolimus (EVR) conversion
  • . History of malignancy or any concomitant malignancy, except:
  • hepatocellular carcinoma,
  • completely treated in-situ cervical carcinoma, or
  • completely treated basal cell carcinoma.
  • . Chronic use of systemic glucocorticoids or other immunosuppressives, or biologic immunomodulators.

Living Donor:

  • There are no exclusion criteria for living donors.

Deceased Donor:

-There are no exclusion criteria for deceased donors.


  • University of California, San Francisco accepting new patients
    San Francisco California 94143 United States

Lead Scientist at UCSF

  • Sandy Feng
    Professor, Surgery, School of Medicine. Authored (or co-authored) 113 research publications


accepting new patients
Start Date
Completion Date
National Institute of Allergy and Infectious Diseases (NIAID)
National Institute of Allergy and Infectious Diseases (NIAID) Division of Allergy, Immunology, and Transplantation (DAIT) Immune Tolerance Network web site
Phase 1/2 Liver Transplant Research Study
Study Type
Expecting 9 study participants
Last Updated