Tailoring cytomegalovirus prophylaxis based on T cell immunity panel assessment in kidney transplant patients at high risk of cytomegalovirus.

Abstract

Valganciclovir prophylaxis against cytomegalovirus (CMV) is recommended for solid organ transplant recipients, but is associated with drawbacks, including expense and leukopenia. Our center adopted a strategy of serial assessment with a CMV-specific T cell immunity panel (CMV-TCIP) and cessation of valganciclovir prophylaxis upon demonstration of adequate CD4+ responses in kidney transplant patients at high risk of CMV disease. We retrospectively reviewed adult recipients of a kidney or pancreas transplant between August 2019 and July 2021 undergoing serial CMV-TCIP monitoring. Included patients were considered high risk for CMV, defined by donor positive (D+)/recipient negative (R-) CMV IgG serostatus, or recipient positive (R+) patients who received induction with a lymphocyte-depleting agent. Prophylaxis was discontinued after a patient's first CMV-specific CD4+ T cell value of ≥0.20%. Risk of clinically significant CMV infection (csCMVi) in those who underwent early discontinuation of CMV prophylaxis and predictors of CMV T cell immunity were analyzed. Of 54 included patients, 22 stopped prophylaxis early due to CMV-specific CD4+ T cell immunity at a median of 4.7 (IQR: 3.8-5.4) months after transplant. No instances of csCMVi were observed in the 22 patients who had prophylaxis discontinued early, of whom 19/22 were CMV R+ and 3/22 were CMV D+/R-. Donor/recipient CMV serostatus was predictive of immunity (p <.001). Early discontinuation of valganciclovir prophylaxis in patients with CMV CD4+ T cellular immunity appears safe and potentially beneficial in this preliminary series, especially in R+ patients. Further study is warranted, given that truncated prophylaxis may yield patient-level benefits.