Incurred sample reanalysis: background, evolution and implementation, with specific consideration for ligand-binding assays

ISR was highlighted as a topic of major interest to the US FDA in 2006, having been previously required, then discontinued, by Canadian regulatory authorities. Following an FDA focus on ISR, this topic has also been emphasized by regulatory agencies in Europe, Asia and Latin America. Extensive discussions on proper implementation of programs have taken place in multiple settings, including pharmaceutical companies, regulatory agencies, professional associations and CROs. These efforts have led to recommendations for ISR conduct that are now included in a final guideline on bioanalytical method validation from the European Medicines Agency, a draft validation guidance from the...