Metabolic and Infectious Complications Post Belatacept Conversion

Study of the Impact of Belatacept Conversion on Metabolic and Infectious Complications in Kidney Transplant Recipients at Grenoble-Alpes University Hospital

The BELASWITCH study is a prospective single-centre study including all kidney transplant patients for whom a conversion from Tacrolimus to Belatacept has been decided by the transplant clinicians of the Grenoble Alpes University Hospital.

Each patient will be included at the time of conversion (patients stable on Tacrolimus for at least 6 months) and will be their own control 1 year after conversion to Belatacept.

The study has two components:

• A "Metabolic" benefit arm: the investigators assume that conversion from Tacrolimus to Belatacept reduces the risk of diabetes by reducing the level of insulin resistance.
• An "Infectious" risk arm: measurement of the viral load of Torque Teno Virus to assess the state of immunosuppression of patients. In this sense, the investigators hypothesise that it could serve as a biomarker of immunodepression in this population.

Inclusion Criteria:

• Adult patients who have had a kidney transplant more than 6 months ago.
• Whose immunosuppression includes stable Tacrolimus (change in dose or dosage form allowed) for at least 3 months.
• Therapeutic plan to change Tacrolimus-based immunosuppression to Belatacept
• Having signed the consent of collection CRB04 - Nephrology Collection (last authorization number: AC-2019-3627) and the BELASWITCH protocol consent.

Exclusion Criteria:

• Subjects under guardianship or deprived of liberty
• Patients who object to the use of their data and/or samples in the research
• Patients having received an immunosuppressive treatment different from the standard one (Tacrolimus, mycophenolate mofetil or Everolimus, corticosteroids)
• ABO and/or HLA incompatible kidney transplantation