Section 207.35 - What changes require a new NDC?(a) Once an NDC has been assigned by FDA, the registrant must propose a new and unique NDC for a drug when there is a change, after the drug is initially marketed, to any of the information identified in paragraphs (b) and (c) of this section. A new NDC must be proposed to FDA for assignment through an updated listing in accordance with § 207.57 .(b) The proposed new NDC must include a new product code when there is a change to any of the following information: (1) The drug's established name or proprietary name, if any;(2) Any active pharmaceutical ingredient or the strength of any active pharmaceutical ingredient;(4) A change in the drug's status, between prescription and nonprescription, or for animal drugs, between prescription, nonprescription, or veterinary feed directive (VFD) status;(5) A change in the drug's intended use between human and animal; or(6) The drug's distinguishing characteristics such as size, shape, color, code imprint, flavor, and scoring (if any).(c) When there is a change only to the package size or type, including the immediate unit-of-use container, if any, the proposed new NDC must include only a new package code and retain the existing product code unless all available package codes have already been combined with the existing product code in NDCs assigned by FDA.