Prevention of Cytomegalovirus Disease in Moderate-Risk (D+/R+ and D-/R+) Renal Transplant Recipients Receiving Basiliximab Induction Therapy: an Efficacy and Safety Evaluation of 3 vs. 6 Months of Low-Dose Valganciclovir

Purpose: Cytomegalovirus (CMV) recipient-positive (D+/R+ or D-/R+) patients represent the largest group of at-risk renal transplant recipients (RTR).  Practice guidelines on CMV prevention in moderate-risk patients give no recommendations on CMV prophylaxis when patients receive basiliximab. This study compared the efficacy and safety of 3 vs. 6 months of low-dose VGC prophylaxis in moderate-risk RTR following basiliximab induction.

Methods: A multicenter, retrospective analysis of 268 adult RTR (9/1/2005-10/31/2010) receiving VGC 450mg/day (dose adjusted for renal function):  Group 1 (n=195) for 3 months, Group 2 (n=73) for 6 months. All patients received initial immunosuppression with tacrolimus, mycophenolate (MPA) and corticosteroids.  The primary endpoint was CMV disease within 1-year. The rates of T-cell-medicated rejection (TCMR), antibody-mediated rejection (AMR), graft loss, patient survival, opportunistic infections (OI), leukopenia and early VGC discontinuation (DC) were assessed.

Results: Patient demographics and transplant characteristics were comparable, with the exception of Group 1 containing more Hispanics and less Caucasians, as well as more deceased-donor transplants.  There were more patients in Group 2 with a previous transplant.  In terms of immunosuppression, more patients in Group 2 received early steroid withdrawal.  Tacrolimus trough concentrations were similar between groups throughout the analysis, but MPA daily doses were slightly lower in Group 2 at month 6.

12 Month Efficacy Analysis	Group 1	Group 2	P-value
CMV disease	1 (0.5%)	2 (2.7%)	0.18
TCMR	18 (9.2%)	12 (16.4%)	0.13
AMR	1 (0.5%)	3 (4.1%)	0.06
Graft Loss	9 (4.6%)	4 (5.5%)	0.76
Patient Survival	191 (97.9%)	69 (94.5%)	0.67
OI	28 (14.4%)	11 (15.1%)	0.85

Group 2 had more patients develop leukopenia at post-op months 4 (p=0.008), 5 (p=0.0005) and 6 (p=0.003). The rate of early VGC DC due to myelosuppression was higher in Group 2 (p=0.001).

Conclusion: Both regimens provide similar CMV prophylaxis efficacy, but the prolonged course was associated with more leukopenia.  The short-course of VGC may also provide significant cost avoidance.