AUTHOR=Morel Antoine, Hoisnard Léa, Dudreuilh Caroline, Moktefi Anissa, Kheav David, Pimentel Ana, Sakhi Hamza, Mokrani David, Attias Philippe, El Sakhawi Karim, Champy Cécile Maud, Remy Philippe, Sbidian Emilie, Grimbert Philippe, Matignon Marie TITLE=Three-Year Outcomes in Kidney Transplant Recipients Switched From Calcineurin Inhibitor-Based Regimens to Belatacept as a Rescue Therapy JOURNAL=Transplant International VOLUME=35 YEAR=2022 URL=https://www.frontierspartnerships.org/articles/10.3389/ti.2022.10228 DOI=10.3389/ti.2022.10228 ISSN=1432-2277 ABSTRACT=Background: The long-term benefits of conversion from calcineurin inhibitors (CNIs) to belatacept in kidney transplant recipients (KTr) are poorly documented.Methods: A single-center retrospective work to study first-time CNI to belatacept conversion as a rescue therapy [eGFR <30 ml/min/1.73 m2, chronic histological lesions, or CNI-induced thrombotic microangiopathy (TMA)]. Patient and kidney allograft survivals, eGFR, severe adverse events, donor-specific antibodies (DSA), and histological data were recorded over 36 months after conversion.Results: We included N = 115 KTr. The leading cause for switching was chronic histological lesions with non-optimal eGFR (56.5%). Three years after conversion, patient, and death-censored kidney allograft survivals were 88% and 92%, respectively, eGFR increased significantly from 31.5 ± 17.5 to 36.7 ± 15.7 ml/min/1.73 m2 (p < 0.01), the rejection rate was 10.4%, OI incidence was 5.2 (2.9–7.6) per 100 person-years. Older age was associated with death, eGFR was not associated with death nor allograft loss. No patient developed dnDSA at M36 after conversion. CNI-induced TMA disappeared in all cases without eculizumab use. Microvascular inflammation and chronic lesions remained stable.Conclusion: Post-KT conversion from CNIs to belatacept, as rescue therapy, is safe and beneficial irrespective of the switch timing and could represent a good compromise facing organ shortage. Age and eGFR at conversion should be considered in the decision whether to switch.