How can one arrange the shipment of a vial containing a vaccine initially released for clinical trial purposes, but now intended for return to a laboratory for investigation following a complaint? Should the sample be re-labeled before shipment? If the vaccine is located at a hospital in, for example, the UK and needs to be returned to a laboratory in the EU for examination, how can this be organized? Are there specific requirements for transport or packaging materials? The vaccine is non-hazardous, and the vial is empty after use.