Efficacy supplement is a supplement to an approved NDA proposing to make one or more related changes from among the following changes to product labeling:
(1) Add or modify an indication or claim;
(2) Revise the dose or dose regimen;
(3) Provide for a new route of administration;
(4) Make a comparative efficacy claim naming another drug product;
(5) Significantly alter the intended patient population;
(6) Change the marketing status from prescription to over-the-counter use;
(7) Provide for, or provide evidence of effectiveness necessary for, the traditional approval of a product originally approved under subpart H of this part; or
(8) Incorporate other information based on at least one adequate and well-controlled clinical study.
21 CFR § 314.3
The definitions and interpretations contained in section 201 of the Federal Food, Drug, and Cosmetic Act apply to those terms when used in this part and part 320 of this chapter.