Determinants of virological outcomes in kidney transplant recipients treated with maribavir for refractory cytomegalovirus infection.

Maribavir has demonstrated promising efficacy in treating refractory cytomegalovirus (CMV) infections among solid organ transplant recipients; however, factors influencing favorable outcomes remain uncertain. We conducted a retrospective cohort study that involved 88 kidney transplant recipients (KTRs) from 22 transplantation centers, all of whom had refractory CMV infections treated with maribavir (63 with and 25 without ganciclovir resistance mutations). CMV clearance at week 8 was achieved in 45 KTRs (51.1%). Among the 49 KTRs (55.7%) who achieved CMV clearance within 16 weeks, 37 (42%) did not develop CMV recurrence. Notably, CMV DNA levels <10 000 international unit/mL at the time of maribavir initiation (odds ratio, 3.21; 95% confidence interval, 1.29-9.54; P = .016) and asymptomatic CMV infection (odds ratio, 3.22; 95% confidence interval, 1.28-9.0; P = .017) were identified as independent factors associated with CMV clearance within 16 weeks without recurrence. Maribavir resistance mutations were identified in 18 KTRs (20.45%), predominantly among those who failed to achieve CMV clearance (35.9%) and those who experienced CMV recurrence (33.3%). In summary, refractory CMV infections characterized by high levels of CMV DNAemia or symptomatic presentations are more challenging to treat with maribavir. These findings may support the development of new strategies for patients at risk of poor outcomes.