A Case Study in AAV Gene Therapy Viral Shedding

With remarkable growth of the viral vector-based gene therapy programs over the past decade, assessment of shedding of viral vectors has become a regulatory requirement, and health authorities in the United States, Canada and European Union have issued guidelines for the conduct vector shedding studies. Shedding is reference to the release of the viral vector into the excreta of the treated subjects and subsequent release of the virus into the environment. Vector shedding raises the likelihood of transmission from dosed subjects to untreated individuals. For example, members of the household or healthcare professional responsible for the care of the treated patient may at risk for exposure. Shedding data may be used to develop measures to prevent transmission of the virus. These data could also be used to establish the duration of the viral vector release, the shedding profile as well as the end of transmission risk. In this talk, we will provide an overview of the regulatory agency expectations regarding the assessment of viral vector shedding as well as a specific case study in clinical vector shedding.