Comparing Letermovir and Valaciclovir for Treating CMV Infection in Pregnant Women with Infected Fetuses

What this Trial Is About

Researchers are investigating whether the antiviral drug Letermovir is more effective than Valaciclovir in treating pregnant women carrying fetuses infected with cytomegalovirus CMV from a first trimester infection. This study focuses on improving outcomes by reducing viral replication in fetuses to increase the number of neonates with negative CMV PCR results at birth, which may lower the risk of neurological and hearing problems that often occur with congenital CMV. The trial is a Phase 3 randomized study comparing these two antiviral treatments. Participants will receive either daily Letermovir tablets 240 mg plus a placebo for Valaciclovir or daily Valaciclovir 8 grams total per day plus a placebo for Letermovir until delivery or termination of pregnancy. The study includes monitoring fetal health via ultrasound and MRI at baseline and follow-up visits at weeks 2, 4, and 6 of treatment. The trial also assesses changes in viral load in various samples, including blood, amniotic fluid, saliva, and urine, and measures drug concentrations in cord blood, placenta, and neonatal blood. During the study, participants will undergo regular clinical visits with evaluations of maternal and fetal health, laboratory tests, imaging studies, and compliance checks up to 39 weeks of gestation. Researchers will monitor neonatal outcomes at birth and track the development of long-term sequelae up to two years of age. Safety assessments include maternal blood counts and organ function tests. The primary outcome is the proportion of neonates with negative CMV PCR in blood collected within the first day of life or at termination of pregnancy. Secondary outcomes include birthweight, placental weight, and the number and type of long-term complications.

Prenatal Treatment of Congenital Cytomegalovirus Infection With Letermovir Versus Valaciclovir