Valganciclovir Therapy in Infants and Children With Congenital CMV Infection and Hearing Loss

Congenital cytomegalovirus (CMV) infection is the most frequent known viral cause of mental retardation, and is the leading non-genetic cause of sensorineural hearing loss in many countries including the United States. This is a Phase II international, multi-center, double-blind, placebo-controlled evaluation of 6 weeks of oral valganciclovir treatment or 6 weeks of placebo for fifty-four male and female infants/toddlers 1 month through 3 years of age (up to 4 years of age) with virologically-confirmed congenital CMV infection and hearing loss. Patient who are between 1 month and 4 years of age and who have SNHL (Sensorineural Hearing Loss) and are eligible for enrollment. The expected study duration is 3.5 years from enrollment of first study subject. The primary objective is to assess whether a six week course of oral valganciclovir can stabilize the hearing of children with congenital CMV infection who present with hearing loss. The secondary objective is to define the following responses as a function of systemic exposure to ganciclovir (active metabolite of valganciclovir): CMV viral load in blood; CMV viral load in urine; and CMV viral load in saliva. Also, to define the safety and tolerability of valganciclovir in enrolled subjects. The tertiary objective is to define the pharmacokinetics of ganciclovir (metabolite) following administration of valganciclovir (prodrug) in enrolled subjects.