The present invention relates to a packaged auto injector set. It comprises a partly transparent medicament container, a hollow auto injector body with the medicament container forming the auto injector, and a non-oxygen permeable package (2) with an opening arrangement (3) for opening the package (2). The auto injector body has at least two apertures (4) allowing for visual control of the medical composition, at least a part of the package (2) is transparent visual control of the medical composition and the packaged auto injector set comprises at least one blocking arrangement (5), which is non-transparent to at least ultraviolet light. The present invention also relates to a method for filling a package (2) with an auto injector. The method comprises inserting the auto injector into the package (2) in a non-inert environment and under atmospheric pressure, replacing the air in the package (2) with inert atmosphere by one or several cycles of removing air and inserting inert gas through the opening. The opening is sealed under vacuum.
