A new paediatric formulation of valaciclovir: development and bioequivalence assessment

A paediatric formulation of valaciclovir with acceptable palatability, good pharmaceutical quality and stability, and with the possibility of flexible dosing is currently not available. A preparation of valaciclovir liquid using crushed tablets as described in the US Food and Drug Administration label information was found not to be adequate for use in daily practice.1 The mean relative bioavailability of this liquid compared with the tablets was reported to be 91.1% (SD, 33.1%), but was not investigated following the regulatory guidance for bioequivalence testing.2 Aim of this study was to develop a new paediatric formulation and to assess the bioequivalence of this new formulation compared with the brand named valaciclovir tablets. An oral liquid was developed because this is generally considered acceptable for use in infants and young children.3 Dosing accuracy, use of non-toxic excipients, palatability and good pharmaceutical stability for an acceptable period of time were taken into account during development. A solution …