Alemtuzumab is approved for the treatment of relapsing-remitting MS and is used off-label for patients with chronic lymphocytic leukemia and as induction and antirejection therapy in kidney transplant recipients. 1 Guillain-Barré syndrome (GBS) or chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) complicating alemtuzumab treatment was reported in 9 patients with hematologic malignancy or MS. 1-3 The risk of GBS or CIDP in solid organ transplant recipients treated with alemtuzumab is unknown. Rabbit antithymocyte globulin (rATG) is another T cell-depleting drug used to treat acute kidney allograft rejection. Only 1 patient was reported who developed GBS after rATG treatment for aplastic anemia. 4 We found no reports of GBS or CIDP complicating rATG treatment in kidney transplant recipients. Here, we investigated the frequency, type, and outcome of GBS and CIDP in a single-center cohort of kidney transplant recipients treated with either alemtuzumab or rATG. Methods Study design A retrospective analysis was performed of a cohort of kidney transplant recipients who received either alemtuzumab (Campath, Sanofi-Genzyme, Cambridge, MA) or rATG (Thymoglobulin, Sanofi-Genzyme) between 2002 and 2018 in the Erasmus MC, Rotterdam. Alemtuzumab was administered as a single dose of 30 mg subcutaneously and rATG in a dose of 4 mg/kg and nog g/kg. Statistical methods Continuous variables are presented as median and interquartile ranges (IQRs). The 95% CIs were calculated with the modified Wald method. For statistical analysis, SPSS version 21 (SPSS Inc., Chicago, IL) was used. Standard protocol approvals, registrations, and patient consents The study was approved by the Erasmus MC Medical Ethical Review Board (number 2018-1430). Results Between 2002 and 2018, 2,788 patients received a kidney transplant at our center. Alemtuzumab was administered to 143 (5.1%) patients and rATG to 108 (3.9%) patients. The total follow-up period of patients treated with alemtuzumab was 3.0 years (IQR 1.7-4.1 years) for