The current FDA specifications governing grouped submissions state that Application Type and Submission Type have to agree. Accordingly, you would have no trouble grouping NDA labeling supplements.
A grouped submission eliminates the need to submit multiple, identical submissions to different applications. For example, a manufacturing part change might impact a dozen applications. In the age of grouped submissions, a new sequence would be created to note the part change, and that sequence would then point to all other applications affected.
What has changed is the FDA’s methodology for collecting and organizing metadata associated with each application. The old M1 specifications arranged information in a flat structure, i.e., amendments could be related to other amendments. In the new M1 specifications, metadata is arranged in a hierarchy.
The M1 initiative, specifically the updated guidelines for Ad Promo submissions, is an example of the FDA gently nudging sponsors to adopt practices that will benefit industry as a whole. The draft guidance on the Ad Promo topic states “the Agency is currently able to process, review, and archive electronic formats in eCTD and firms are strongly encouraged to make such submissions electronically.”
The FDA’s goal to get safe and effective treatments to patient populations in a timely manner demands a reliable drug approval cycle. Changes to the Module 1 specification align to this goal.