Characterization of Ganciclovir Dosing for the Management of Cytomegalovirus in Solid Organ Transplant Recipients Receiving Sustained Low-Efficiency Dialysis.

Background: The optimal dosing of intravenous ganciclovir in patients receiving sustained low-efficiency dialysis (SLED) remains unclear.

Objective: The primary objective is to characterize the dosing of ganciclovir for treating and preventing cytomegalovirus (CMV) in Solid Organ Transplant Recipients receiving SLED. The secondary objective is to evaluate the safety and efficacy of the dosing practices described in this study.

Methods: Retrospective review of electronic medical records from solid organ transplant recipients (SOTRs) admitted to the Medical Surgical Intensive Care Unit at the Toronto General Hospital (TGH) between November 28, 2016, and September 1, 2021, was conducted. Patients concurrently receiving ganciclovir and SLED were included.

Results: Among the 27 encounters for CMV prevention, 18 patients underwent 8-hour SLED, 6 underwent 24-hour SLED, and 3 received other SLED durations. Most patients (80%) on 8-hour SLED began ganciclovir at 2.5 mg/kg/d, whereas 80% of those on 24-hour SLED started at 5 mg/kg/d. No breakthrough viremia occurred at 5 mg/kg/d, with 1 instance at 2.5 mg/kg/d. Cytopenia rates were higher at 5 mg/kg/d (33% vs 20%). For treatment (n = 20), 16 patients underwent 8-hour SLED, 2 underwent 24-hour SLED, and 2 underwent 12-hour SLED. Most (75%) on 8-hour SLED started at 2.5 mg/kg/d, whereas all on 24-hour SLED began at 5 mg/kg/d. Viral eradication rates were 75% and 60% at 2.5 and 5 mg/kg/d, respectively, with higher cytopenia rates at 5 mg/kg/d (37.5% vs 0%). Dose adjustments were primarily in response to refractory disease or cytopenia.

Conclusion And Relevance: At our institution, ganciclovir dosing patterns suggest that for patients requiring 8-hour SLED, there is clinician comfort in using 2.5 mg/kg/d for prevention and 5 mg/kg/d for treatment. In 24-hour SLED, 5 mg/kg/d may be considered for prevention. Higher doses may be considered for CMV treatment; however, we found greater variability in the dosing practices for these patients. Further research with larger sample sizes and ganciclovir drug-level assessments is needed to optimize dosing strategies for CMV treatment.