In utero treatment of congenital cytomegalovirus infection with valacyclovir in a multicenter, open-label, phase II study.
Leruez-Ville M, Ghout I, Bussières L, Stirnemann J, Magny JF, Couderc S, Salomon LJ, Guilleminot T, Aegerter P, Benoist G, Winer N, Picone O, Jacquemard F, Ville Y.
Source : Am. J. Obstet. Gynecol.
2017 May 26
Pmid / DOI: 27083761
OBJECTIVE: We evaluated the efficacy of oral valacyclovir, 8 g daily, for pregnant women carrying a symptomatic cytomegalovirus-infected fetus, targeting a high-risk group for developing both neurosensory and neurological impairment.
STUDY DESIGN: We designed a multicenter, open-label, phase II study with 1 arm, using one of Simon's optimal 2-stage designs. Symptomatic fetuses were defined by the presence of measurable extracerebral or mild cerebral ultrasound symptoms. They were treated in utero from prenatal diagnosis at a median of 25.9 weeks' gestation until delivery or termination of pregnancy. Fetuses with severe brain anomalies on ultrasound were not included as were cases completely asymptomatic at presentation, because treatment was unlikely to modify either outcome. The primary endpoint was the proportion of asymptomatic neonates born to treated mothers.
RESULTS: At the interim analysis, 8 of 11 women delivered an asymptomatic neonate (required: ≥7). In step 2, 32 additional cases were included for a total of 43; the final number of asymptomatic neonates was 34, more than the 31 required to indicate efficacy according to the Simon 2-stage design. They remained asymptomatic at 12 months. High-dosage valacyclovir given for a median of 89 days to pregnant women carrying a moderately infected fetus was efficient at giving birth to asymptomatic neonates. Fetal blood viral loads decreased and platelet counts increased, both significantly (P = .01 and P < .001, respectively), between treatment initiation and birth after treatment completion, regardless of duration of fetal infection. Compared with a historical cohort obtained by a metaanalysis of the literature, the use of valacyclovir (8 g daily) significantly increased the proportion of asymptomatic neonates from 43% without treatment to 82% with treatment. Although the pill burden was high (16 pills a day) adherence to treatment was >90%. Finally, valacyclovir at this high dosage was extremely well tolerated.
CONCLUSION: Our results indicate that high-dosage valacyclovir given in pregnancy is effective for improving the outcome of moderately symptomatic infected fetuses. Although this study is not a randomized controlled trial, this is the first study reporting the efficacy of an antiviral drug to treat cytomegalovirus-infected fetuses. Moreover, this first study will allow new trials to be conducted, using valacyclovir as a baseline safe and effective treatment in pregnancy, to be compared to the new emerging and more potent anticytomegalovirus drugs that have not currently been tested in pregnancy.