The 2VAL study: Randomized comparison of valganciclovir vs. valacyclovir for cytomegalovirus prophylaxis after renal transplantation

Introduction: Valganciclovir is the most common drug used for cytomegalovirus (CMV) prophylaxis at present. Nevertheless, also the efficacy of high-dose valacyclovir was documented in randomized trials together with reduced risk of acute rejection. There is no head-to-head comparison of both drugs. Methods: A total of 99 renal transplant recipients at risk for CMV (D+/R-, D+/R+, D-/R+) were randomized to 3-month prophylaxis either with valganciclovir (900mg once daily, n=50) or valacyclovir (2g four times daily, n=49). Quantitative PCR for CMV DNA in whole blood was assessed every second week for 3 months and at 4, 5, 6, 9 and 12 months. Results: The 12-month incidence of CMV viremia was comparable (31% vs. 42%, P=0.205) in the valganciclovir and valacyclovir groups, respectively. The incidence of CMV disease was low and not different (2% vs. 2%, P=0.958). A numerically lower rate of biopsy-proven acute rejection during 12 months was observed in valganciclovir treated patients (16% vs. 26%), however the difference did not reach statistical significance (P=0.264). Conclusions: Valganciclovir and valacyclovir prophylaxis are equally effective in the prevention of CMV disease after renal transplantation. A trend toward higher rate of acute rejection with valacyclovir prophylaxis requires further investigation.