Age: 18+
Healthy Volunteers: Not accepted
Inclusion Criteria:
1. Subject must be able to understand and provide informed consent
2. 1-10 years post-liver transplant
3. Tacrolimus-containing maintenance immunosuppression (IS) regimen without corticosteroid. Mycophenolate mofetil (MMF) dose must be <=2000 mg daily or mycophenolic acid (MPA) dose<=1440 mg daily (if on MMF or MPA). Tacrolimus level must be <8 ng/ml on the 2 most recent laboratory results within 3 months.
4. Gamma glutamyl transferase (GGT) and alanine transaminase (ALT) <= upper limit of normal (ULN)
5. Estimated glomerular filtration rate (GFR) >=40 mL/min/1.73 m\^2 using the CKD-EPI 2021 equation
6. Female subjects of reproductive potential must have a negative pregnancy test upon study entry
7. Female subjects with reproductive potential, must agree to use Food and Drug Administration (FDA)-approved methods of birth control for the duration of the study
8. Subjects must have current vaccinations or documented immunity as per the Division of Allergy, Immunology, and Transplantation (DAIT) vaccine guidance for subjects in transplant trials
9. Negative result of most recent tuberculosis (TB) testing or appropriately completed latent tuberculosis infection (LTBI) therapy. Testing should be conducted using either a purified protein derivative (PPD) or interferon-gamma release assay (i.e., QuantiFERON-TB, T-SPOT.TB). Results from tests performed within 12 months prior to study entry are acceptable in the absence of any intervening exposure to TB. Subjects with a positive test for LTBI must complete appropriate therapy for LTBI. LTBI treatment regimens should be among those endorsed by the Centers for Disease Control and Prevention (CDC)
10. Negative FDA-approved test for human immunodeficiency virus (HIV) diagnosis at screening or as documented in medical record, up to 12 months prior to screening)
11. Negative hepatitis C antibody test at screening or as documented in medical record, up to 12 months prior to screening, in subjects without a history of hepatitis C. If there is a history of treated hepatitis C, then documentation of two consecutive negative hepatitis C virus (HCV) quantitative RNA polymerase chain reaction (PCR) tests separated by at least 3 months is required. Untreated subjects with positive HCV antibody and a single negative quantitative HCV RNA are eligible. Historical negative HCV RNA results are acceptable in the above two cases with positive HCV antibody
12. Negative hepatitis B surface antigen and negative hepatitis B core antibody in subjects without a history of hepatitis B virus (HBV) infection, up to 12 months prior to screening. Those with known hepatitis B infection or positive hepatitis B surface antigen or positive hepatitis B core antibody must be on antiviral therapy and have negative HBV DNA quantitative PCR at screening
Exclusion Criteria:
1. Inability of a subject to comply with study protocol
2. Any medical condition requiring chronic systemic corticosteroid, e.g., severe reactive airways disease. Use of inhaled steroids is not an exclusion
3. Autoimmune cause of liver disease (including autoimmune hepatitis (AIH), primary sclerosing cholangitis, primary biliary cirrhosis)
4. Diagnosis of rejection within 52 weeks prior to screening
5. Donor human leukocyte antigen (HLA) typing unavailable or inadequate for assigning donor-specific antibody (DSA)
6. Need for uninterrupted anticoagulation
7. Known active current or history of invasive fungal infection, or mycobacterial infection within 1 year prior to screening
8. Human immunodeficiency virus (HIV)-positive
9. Serious uncontrolled concomitant major organ disease
10. Recipient of non-liver solid organ or bone marrow transplant
11. Any infection requiring hospitalization and IV antibiotics within 4 weeks of screening or oral antibiotics within 2 weeks
12. Malignancy within the last 5 years except treated basal and squamous cell cancer of the skin or treated in situ cervical cancer. History of hepatocellular carcinoma in the explanted liver is acceptable provided that
1. the last alpha fetoprotein obtained within 3 months prior to liver transplantation was < 400 microg/L, and
2. the recipients' explanted liver did not have evidence of increased risk of recurrent cancer, i.e., explant was within the Milan criteria, with no vascular invasion, and with no cholangiocarcinoma morphology
13. Neutropenia (absolute neutrophil count or ANC <1000 microliter) within 4 weeks prior to study enrollment
14. History of hypersensitivity to Epoetin (EPO) or mammalian Target of Rapamycin inhibitor (mTOR-I)
15. History of angioedema
16. History of hereditary disorders of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption. History of lactose intolerance is not an exclusion
17. History of genetic disorders predisposing to thrombosis including but not limited to Factor V Leiden mutation, prothrombin 20210, protein C deficiency, protein S deficiency, antithrombin III deficiency
18. History of venous or arterial thrombosis or thromboembolism, acute MI, or thrombotic stroke except for a history of isolated portal vein thrombosis in the setting of hepatic cirrhosis
19. History of Budd Chiari syndrome
20. Hemoglobin > 13.5 g/dl
21. Plasma fibrinogen or D-dimer level > ULN
22. Planned major surgery within the next 12 months
23. Uncontrolled severe hypertension
24. Uncontrolled clinically significant cardiac arrhythmia
25. Proteinuria with urine protein/creatinine >0.5 g/g
26. Severe hyperlipidemia with total cholesterol >350 mg/dl or triglycerides >1000 mg/dl
27. Current alcohol, drug, or chemical dependency
28. Currently pregnant or nursing
29. Current treatment with an estrogen-containing oral contraceptive, or systemic estrogen replacement therapy
30. Treatment with an immunomodulatory biological drug within 12 weeks of study entry
31. Immunization with live vaccine within 2 weeks of study baseline visit
32. Treatment with any investigational agent within 4 weeks (or 5 half-lives of investigational drug, whichever is longer) of screening
33. Past or current medical problems or findings from physical examination or laboratory testing that are not listed above, which, in the opinion of the investigator, may pose additional risks from participation in the study, may interfere with the subject's ability to comply with study requirements or that may impact the quality or interpretation of the data obtained from the study