Table 2.

Characteristics of antiviral prophylaxis and preemptive therapy in patients who underwent renal transplant

Feature	Universal antiviral prophylaxis	Preemptive therapy
Procedure	Antiviral medication given to all patients at risk of CMV for 3–6 mos after transplant	Weekly CMV PCR monitoring with initiation of antiviral therapy with CMV DNAemia detection
Antiviral	i.v. ganciclovir/PO valganciclovir; letermovir	N/A
Efficacy against CMV disease prevention	Good efficacy; very low risk during prophylaxis period	Good efficacy
Late-onset (i.e., after 3–6 mos after transplant) CMV disease	Higher risk (after prophylaxis period)	Lower risk
Cost attributable to:	Medication	Laboratory monitoring
Feasibility	Easy to implement as frequent lab visits are not required	Requires weekly monitoring of labs
Toxicity	Higher rates of myelosuppression	Lower risk of drug toxicity
Acute rejection	Lower risk of acute rejection	Unknown effect on rejection
Resistance	Potential low risk with prolonged exposure	Uncommon
Duration of prophylaxis	Dependent on risk status: High risk (D+/R-) 6 mos Intermediate risk (R+) 3 mos Low risk (D-/R-) 3 mos	12 wks after transplant

CMV, cytomegalovirus; D+/R-, donor-seropositive/recipient-seronegative; D-/R-, donor-seronegative/recipient-seronegative; DNAemia, DNA viremia; N/A, not applicable; PCR, polymerase chain reaction; PO, oral; R+, recipient-seropositive.

Adapted from Kotton et al.²⁵