Companies may convert an existing DMF in non-CTD format to CTD format. In such cases, the FDA advises DMF holders to submit an amendment that contains all applicable CTD-specified sections to the material in the DMF. Each section must be complete and current. For drug substances and excipients, companies must submit all sections of 3.2.S in Module 3. For drug products, companies must submit all sections of 3.2.P in Module 3. If the reformatting causes changes in the DMFs technical content—e.g., adds new information—the cover letter for the new submission must describe these changes. DMFs in CTD format must follow CTD Guidance, e.g., be paginated within each section. This supersedes DMF guidance.