The eCTD contains an electronic table of contents also referred to as a backbone that manages all the metadata for an application.

This backbone is broken down into five modules. Documents are placed appropriately into modules, which are graphically presented as the CTD Triangle.

Module 1 references regional information such as forms, cover letter, labeling, and investigational brochures.

Module 2 references summaries such as quality, clinical, and non-clinical summaries.

Module 3 references quality information.

Module 4 references non-clinical information.

Module 5 references clinical information.

The next screen shows the CTD Triangle.