Jojo63,
follow ISO 10993-1:2009, which is the applicable standard for medical devices in (indirect) patient contact.
USP and ESP data of your raw materials may support conclusions in your biocompatibility evaluation, but it's also your manufacturing processes and your intended use that has to be assessed in a risk management process for the biological risks (typically for mucosal membrane contact: cytotoxicity, irritation, sensitization). Start off with a material characterization and follow the flow chart given in ISO 10993-1.
Don't forget to consider any potential drug-container interaction.
HTH,
Gerhard