Pilot Study: Interest of Belatacept as a Non-nephrotoxic Immunosuppressive Treatment in Cardiac Transplant Patients at Risk of Chronic Renal Failure (BELACOEUR)

Inclusion Criteria: Cardiac transplant patients for 3 months Over 18 years of age No Donor Specific Antibodies at inclusion (positive threshold average fluorescence intensity (MFI)\> 2000) Having a GFR (DFG in french) is the single best indicator of overall renal function \< 30ml/min calculated according to the formula CKD EPI or a decrease in GFR of more than 50% between the day of the heart transplant and 3 months, stable for 15 days. Induction treatment with anti-lymphocyte serum Virus d'Epstein-Barr positive serology Having signed the consent after receiving informed information Negative pregnancy test for patients of childbearing age, and agreement to use effective contraception throughout the study and 6 weeks after the end of the study Having no difficulty in understanding and communicating with the investigator and his representatives Beneficiaries of a Social Security scheme Exclusion Criteria: The criteria for non-inclusion are: 2nd heart transplant or other solid organ transplant History of rejections Cellular or humoral rejection at myocardial biopsy of 3 months post Transplantation Cardiac Current viral infection of type cytomegalovirus, Virus d'Epstein-Barr, hepatitis C virus, hepatitis V virus..... Human immunodeficiency virus positive serology Ongoing participation in another clinical study Any clinical condition that the investigator considers incompatible with the conduct of the study under acceptable safety conditions: (in particular, progressive infection, progressive cardiovascular complication, progressive neoplastic disease) Inability of the patient to comply with study procedures Pregnant or breastfeeding women Person under guardianship, curators or safeguard of justice