A process for lyophilizing a solution of an active agent in a container is provided. Solution of active agent is deposited into a container, the container is covered with a covering plate and placed inside a lyophilizing apparatus. Lyophilization can be conducted to dryness by radiation, convection or both. Also provided is a device made by this process, an active agent-plastic administration device (e.g., a syringe), containing an active agent in the form of lyophilized cake, and an array of such administration devices.