Inclusion Criteria:
Key inclusion criteria for both cohorts
- Written informed consent obtained before any assessment.
- Male or female patient ≥ 18 years old.
- Up to date vaccination as per local immunization schedules.
Key inclusion criteria specific to Cohort 1:
- Recipients of a primary kidney transplant from a brain-dead donor, living unrelated or non-human leukocyte antigen (HLA) identical living related donors.
- Recipients of a kidney with a cold ischemia time < 24 hours.
Key inclusion criteria specific to Cohort 2:
- Recipients of a primary graft received 6 to 24 months prior enrollment, on a regimen containing TAC+MMF/ Enteric-coated mycophenolate sodium (EC-MPS)±corticosteroids (CS).
- Patients with an actual eGFR according to Modification of Diet in Renal Disease (MDRD-4) ≥ 45 mL/min/1.73m2.
Exclusion Criteria:
Key exclusion criteria for both cohorts
- Recipient who tests positive for anti-HIV, HBsAg or anti-HCV (without proof of sustained viral response (SVR12) after anti-HCV treatment) within 28 days prior to baseline visit.
- Recipient who tests negative for Epstein Barr virus (EBV) within 28 days prior to baseline visit.
- Evidence of advanced liver disease (Child-Pugh C), or any sign of liver decompensation.
- Patient with severe systemic infections, current or within the two weeks prior to randomization.
- History of malignancy of any organ system, treated or untreated, within the past 5 years, regardless of whether there is evidence of local recurrence or metastases, with the exception of localized excised non-melanomatous skin lesions.
- Patients who weighed less than 30 kg or more than 180 kg.
Key exclusion criteria specific to Cohort 1:
- Multi-organ transplant recipients, including en bloc and dual kidney transplantation, or prior kidney transplant
- Recipients of an organ from a donor after cardiac death.
- Recipient of an organ from an HLA identical living related donor.
- ABO incompatible or complement-dependent lymphocytotoxic crossmatch positive transplant (isolated positive B cell crossmatches were not an exclusion criterion).
- Recipients of kidneys from donors who were older than >65 years.
- Recipients of kidneys from donors with terminal serum creatinine > 2 mg/dL.
- Patients at high immunological risk for rejection as determined for assessment of anti-donor reactivity:
- high panel reactive antibodies> 20% or
- Presence of pre-formed DSA. Results 12 weeks prior to enrollment were acceptable if no blood transfusion or abortion occurred during this period.
- Recipient of a kidney from a donor who tests positive for HIV, HBsAg or HCV.
Key exclusion criteria to Cohort 2
- Recipients of a kidney re-transplant.
- Recipient of a multi-organ transplant, including en bloc and dual kidney transplantation.
- DSA within 12 weeks prior enrollment.
- eGFR decline ≥10.0 mL/min within 12 weeks prior enrollment.
- Ongoing rejection or rejection that required treatment within 12 weeks prior enrollment.
- Severe humoral and/or cellular rejection (BANFF ≥ IIb) within 12 weeks before enrollment.
- Proteinuria > 1 g/day or UPCR >1.2 mg/mg at time of enrollment