Abatacept Conversion in Kidney Transplantation

Inclusion Criteria:

Individuals who meet all of the following criteria are eligible for enrollment as study participants:

1. Adult (age ≥18 years currently)
2. First-time renal transplant recipients of either living donor or deceased donor

1. Treatment with belatacept from the time of transplant
2. At least 2 years post-transplant and off CNI therapy for at least 6 months
3. Patients at low immunologic risk

1. First time transplant
2. HLA antibody screen with PRA < 80% against class I and class II antigens
3. Negative crossmatch (actual or virtual)
4. No donor specific anti-HLA antibody (DSA)
5. No more than one episode of rejection (Banff grade 1A or greater)
6. No episodes of rejection (borderline or greater) within the last 6 months prior to study participation
7. No rejection of Banff grade IIB or greater
8. Immunosuppression consisting of belatacept (5mg/kg q 1M), mycophenolate mofetil (at least 1000 mg daily), or equivalent mycophenolic acid (720 mg daily) or azathioprine (1- 2 mg/kg daily) dose, and prednisone 5 mg daily.
9. Confirmed Tb screening at the time of transplantation

Exclusion Criteria:

Individuals who meet any of these criteria are not eligible for enrollment as study participants:

1. Repeat renal transplant, or multi-organ transplant recipient
2. History of more than one episode of biopsy-proven acute rejection (Banff grade 1A or greater), or of any episode of rejection of Banff 97 grade IIB or greater, or any rejection (borderline or greater) within the last 6 months
3. Pregnancy (women of childbearing potential must use adequate contraception during study)
4. GFR less than 35
5. Serum creatinine at enrollment more than 30% higher than at 3 months (±4 weeks) prior to randomization
6. Recent history of clinically significant proteinuria (urinary protein/Cr ratio >1.0)
7. Receiving belatacept at a dose other than 5 mg/kg body weight
8. Receiving mycophenolate mofetil at a dose of less than 1000 mg po QD (or mycophenolic acid or azathioprine equivalent).
9. Receiving prednisone at a dose greater than 5 mg po qd within 3 months of enrollment
10. Not currently receiving maintenance immunosuppression with prednisone
11. Active infection, or antibiotic or antiviral drug therapy within 1 month of randomization
12. Evidence of CMV viremia or clinical CMV infection within the last 3 months prior to randomization.
13. BK viremia of greater than 4.3 DNA log copies/mL (greater than 20,000 copies/mL) within 3 months of randomization
14. Known hepatitis B surface antigen-positive or PCR-positive for hepatitis B (testing not required)
15. Known HIV-positivity (testing not required)
16. Presence of donor specific antibody by Luminex single antigen bead assay, or antibody screen (% PRA) above 80%.
17. History of substance abuse or psychiatric disorder not compatible with study adherence and follow up.
18. History of medical noncompliance
19. Untreated latent Tb (as determined from prior Tb screening at the time of transplantation)