Don’t panic, it’s still a couple years away from implementation (probably 2015 is the earliest you could think about submitting in 4.0 format), but we’ll break it to you gently.
Why can’t we “leaf” it alone?
eCTD 4.0 is the implementation of the Electronic Common Technical Document using the RPS (Regulated Product Submissions) standard developed at HL7. RPS came about originally as an FDA initiative to create a single submission standard that can be used for all its divisions: not just eCTDs for drugs and biologics, but veterinary, food additives, cosmetics, devices (and perhaps tobacco).
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