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Electronic Code of Federal Regulations

e-CFR data is current as of February 25, 2020

Title 21Chapter ISubchapter EPart 516Subpart C → §516.161

Title 21: Food and Drugs
Subpart C—Index of Legally Marketed Unapproved New Animal Drugs for Minor Species

§516.161   Modifications to indexed drugs.

(a) After a drug is listed in the index, certain modifications to the index listing may be requested. Any modification of an index listing may not cause an indexed drug to be a different drug (or different combination of drugs) or a different dosage form. If such modification is requested, FDA will notify the holder that a new index listing is required for the new drug or dosage form.

(b) Modifications to the indexed drug will fall under one of three categories and must be submitted as follows:

(1) Urgent changes. (i) The following modifications to an indexed drug or its labeling should be made as soon as possible, and a request to modify the indexed drug should be concurrently submitted:

(A) The addition to package labeling, promotional labeling, or prescription drug advertising of additional warning, contraindication, side effect, or cautionary information.

(B) The deletion from package labeling, promotional labeling, and drug advertising of false, misleading, or unsupported indications for use or claims for effectiveness.

(C) Changes in manufacturing methods or controls required to correct product or manufacturing defects that may result in serious adverse drug events.

(ii) The modifications described in paragraph (b)(1)(i) of this section must be submitted to the Director, OMUMS, in the form of a request for modification of an indexed drug, and must contain sufficient information to permit FDA to determine the need for the modification and whether the modification appropriately addresses the need.

(iii) FDA will take no action against an indexed drug or index holder solely because modifications of the kinds described in paragraph (b)(1)(i) of this section are placed into effect by the holder prior to receipt of a written notice granting the request if all the following conditions are met:

(A) A request to modify the indexed drug providing a full explanation of the basis for the modifications has been submitted, plainly marked on the mailing cover and on the request as follows: “Special indexing request— modifications being effected;”

(B) The holder specifically informs FDA of the date on which such modifications are to be effected and submits two printed copies of any revised labeling to be placed in use, and

(C) All promotional labeling and all drug advertising are promptly revised consistent with modifications made in the labeling on or within the indexed drug package.

(2) Significant changes. (i) The following modifications to an indexed drug or its labeling may be made only after a request has been submitted to and subsequently granted by FDA:

(A) Addition of an intended use.

(B) Addition of a species.

(C) Addition or alteration of an active ingredient.

(D) Alteration of the concentration of an active ingredient.

(E) Alteration of dose or dosage regimen.

(F) Alteration of prescription or over-the-counter status.

(ii) Each modification described in paragraph (b)(2)(i) of this section must go through the same review process as an original index listing and is subject to the same standards for review.

(iii) Each submission of a request for a modification described in paragraph (b)(2)(i) of this section should contain only one type of modification unless one modification is actually necessitated by another, such as a modification of dose necessitated by a modification of the concentration of an active ingredient. Submissions relating to addition of an intended use for an existing species or addition of a species should be submitted separately, but each such submission may include multiple additional intended uses and/or multiple additional species.

(3) Minor changes. All modifications other than those described in paragraphs (b)(1) and (b)(2) of this section including, but not limited to, formulation, labeling, and manufacturing methods and controls (at the same level of detail that these were described in the request for determination of eligibility for indexing) must be submitted as part of the annual indexed drug experience report or as otherwise required by §516.165.

(c) When changes affect the index listing, it will be updated accordingly.

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