Prospective Study of Oral Valganciclovir for Pre-Emptive Therapy of Cytomegalovirus After Allogeneic Stem Cell Transplantation.

We performed a prospective phase II multicentric study with Vgcv in adult patients to evaluate its efficacy and safety in the pre-emptive treatment of CMV-Ag or DNAemia within the first 180 days after SCT (ClinicalTrials.gov Identifier: NCT00386412). The results were compared with those obtained with iv-GCV in a retrospective control group. The primary study endpoint (success) was the achievement of negative CMV-AG/PCR on day 14 of treatment without changing the protocol antiviral (Vgcv or iv-gcv). Secondary end-points were negative CMV-AG/PCR, rate of neutropenia (<500 neutrophils/mm3) and nephrotoxicity, until 35 days after the beginning of treatment. A minimum patient weight of 50 kg was required. Vgcv was given at 900 mg/12h for 14 days (induction therapy) followed by 900 mg/day for another 14 days (maintenance treatment), in both cases adjusted according to renal function. If CMV was positive at day +21, the treatment was considered a failure and Vgcv was stopped.

Here we presented the final results on 90 patients (60 prospective treated with Vgcv and 30 treated with iv-Gcv). There were no differences between Vgcv and iv-Gcv groups in median age (47 vs 49 years), median weight (72,5 vs 62kg), type of donor (55% vs 37% HLA identical siblings, 43% vs 56% unrelated and 2% vs 7% related mismatch), and conditioning regimen (mieloablative 42% vs 57%; reduced intensity in 58% vs 43%). More iv-Gcv patients had acute GVHD II-IV at CMV viremia presentation (12% vs 42%). The majority of the patients where receiving immunosuppression at CMV viremia presentation (97% vs 97%). Median time for CMV-Ag/PCR positivity was 46 days after SCT for both groups.

Two patients developed CMV disease during antiviral therapy: one in the Vgcv group (a proved gastric on day +9 of therapy) and one in the iv-gcv group. At 2 months of follow-up no more cases of CMV disease were diagnosed.

Nuetropenia (<500/mm3): 8 cases in Vgcv group (13.3%) vs 1 case in iv-gcv group (3.3%) (P ns). Only one patient in the iv-gcv group developed nephrotoxicity.

Oral valganciclovir therapy given at a fixed dose in patients over 50 kg for the pre-emptive therapy of CMV in allogeneic patients was effective and with similar toxicity compared with iv-gcv.

No relevant conflicts of interest to declare.