[Federal Register Volume 91, Number 75 (Monday, April 20, 2026)]
[Notices]
[Pages 21000-21002]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2026-07629]


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DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

[Docket No. FDA-2025-D-6130]


Establishing Impurity Specifications for Antibiotics; Draft 
Guidance for Industry; Availability

AGENCY: Food and Drug Administration, HHS.

ACTION: Notice of availability.

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SUMMARY: The Food and Drug Administration (FDA, Agency, or we) is 
announcing the availability of a draft guidance for industry entitled 
``Establishing Impurity Specifications for Antibiotics.'' The draft 
guidance provides recommendations regarding the establishment of 
specifications for organic impurities in antibiotics manufactured by 
fermentation and semi-synthesis. This draft guidance applies to 
antibiotic drugs subject to approval under new drug applications (NDAs) 
and abbreviated new drug applications (ANDAs) and associated type II 
drug substance drug master files (DMFs) referenced in antibiotic NDAs 
and ANDAs. This guidance also applies to nonprescription antibiotic 
drugs, often referred to as over-the-counter (OTC) monograph drugs. By 
providing these recommendations, FDA intends to clarify effective 
control strategies, support the development of high-quality antibiotic 
products, and promote consistency in quality standards.

DATES: Submit either electronic or written comments on the draft 
guidance by June 22, 2026. to ensure that the Agency considers your 
comment on this draft guidance before it begins work on the final 
version of the guidance.

ADDRESSES: You may submit comments on any guidance at any time as 
follows:

Electronic Submissions

    Submit electronic comments in the following way:
     Federal eRulemaking Portal: https://www.regulations.gov. 
Follow the instructions for submitting comments. Comments submitted 
electronically, including attachments, to https://www.regulations.gov 
will be posted to the docket unchanged. Because your comment will be 
made public, you are solely responsible for ensuring that your comment 
does not include any confidential information that you or a third party 
may not wish to be posted, such as medical information, your or anyone 
else's Social Security number, or confidential business information, 
such as a manufacturing process. Please note that if you include your 
name, contact information, or other information that identifies you in 
the body of your comments, that information will be posted on https://www.regulations.gov.
     If you want to submit a comment with confidential 
information that you do not wish to be made available to the public, 
submit the comment as a written/paper submission and in the manner 
detailed (see ``Written/Paper Submissions'' and ``Instructions'').

Written/Paper Submissions

    Submit written/paper submissions as follows:
     Mail/Hand delivery/Courier (for written/paper 
submissions): Dockets Management Staff (HFA-305), Food and Drug 
Administration, 5630 Fishers Lane, Rm. 1061, Rockville, MD 20852.
     For written/paper comments submitted to the Dockets 
Management Staff, FDA will post your comment, as well as any 
attachments, except for information submitted, marked and identified, 
as confidential, if submitted as detailed in ``Instructions''.
    Instructions: All submissions received must include the Docket No. 
FDA-2025-D-6130 for ``Establishing Impurity Specifications for 
Antibiotics.'' Received comments will be placed in the docket and, 
except for those submitted as ``Confidential Submissions,'' publicly 
viewable at https://www.regulations.gov or at the Dockets Management 
Staff between 9 a.m. and 4 p.m., Monday through Friday, 240-402-7500.
     Confidential Submissions--To submit a comment with 
confidential information that you do not wish to be made publicly 
available, submit your comments only as a written/paper submission. You 
should submit two copies total. One copy will include the information 
you claim to be confidential with a heading or cover note that states

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``THIS DOCUMENT CONTAINS CONFIDENTIAL INFORMATION.'' The Agency will 
review this copy, including the claimed confidential information, in 
its consideration of comments. The second copy, which will have the 
claimed confidential information redacted/blacked out, will be 
available for public viewing and posted on https://www.regulations.gov. 
Submit both copies to the Dockets Management Staff. If you do not wish 
your name and contact information to be made publicly available, you 
can provide this information on the cover sheet and not in the body of 
your comments and you must identify this information as 
``confidential.'' Any information marked as ``confidential'' will not 
be disclosed except in accordance with 21 CFR 10.20 and other 
applicable disclosure law. For more information about FDA's posting of 
comments to public dockets, see 80 FR 56469, September 18, 2015, or 
access the information at: https://www.gpo.gov/fdsys/pkg/FR-2015-09-18/pdf/2015-23389.pdf.
    Docket: For access to the docket to read background documents or 
the electronic and written/paper comments received, go to https://www.regulations.gov and insert the docket number, found in brackets in 
the heading of this document, into the ``Search'' box and follow the 
prompts and/or go to the Dockets Management Staff, 5630 Fishers Lane, 
Rm. 1061, Rockville, MD 20852, 240-402-7500.
    You may submit comments on any guidance at any time (see 21 CFR 
10.115(g)(5)).
    Submit written requests for single copies of this draft guidance to 
the Division of Drug Information, Center for Drug Evaluation and 
Research, Food and Drug Administration, 10001 New Hampshire Ave., 
Hillandale Building, 4th Floor, Silver Spring, MD 20993-0002. Send one 
self-addressed adhesive label to assist that office in processing your 
requests. See the SUPPLEMENTARY INFORMATION section for electronic 
access to the draft guidance document.

FOR FURTHER INFORMATION CONTACT: Ashley Boam, Center for Drug 
Evaluation and Research, Food and Drug Administration, 10903 New 
Hampshire Ave., Bldg. 51, Rm. 4192, Silver Spring, MD 20993-0002, 240-
402-6341.

SUPPLEMENTARY INFORMATION:

I. Background

    FDA is announcing the availability of a draft guidance for industry 
entitled ``Establishing Impurity Specifications for Antibiotics.'' This 
draft guidance provides recommendations for establishing specifications 
for organic impurities in antibiotics manufactured by fermentation and 
semi-synthesis. These recommendations can be used to establish 
consistent standards for impurity testing and ensure that batches of 
antibiotic drug products meet appropriate impurity specifications.
    This draft guidance applies to antibiotic drugs subject to approval 
under NDAs and ANDAs submitted under section 505 of the Federal Food, 
Drug, and Cosmetic Act (FD&C Act) (21 U.S.C. 355), associated type II 
drug substance DMFs referenced in antibiotic NDAs and ANDAs, and 
nonprescription antibiotic drugs marketed pursuant to section 505G of 
the FD&C Act (21 U.S.C. 355h) (often referred to as OTC monograph 
drugs). INDs submitted under 21 CFR part 312 should follow the general 
principles outlined in the draft guidance.
    The recommendations in the draft guidance are not intended to be 
applied retroactively (i.e., to antibiotic drugs submitted in 
applications or their supplements, or antibiotic drugs marketed before 
finalization of this guidance). This is to prevent potential 
manufacturing discontinuances or interruptions of marketed antibiotic 
drugs that could lead to supply chain disruptions. However, applicants 
and manufacturers of marketed antibiotic drugs should consider updating 
impurity specifications in accordance with this draft guidance when 
making major changes, such as replacing a source of active 
ingredient(s), and to ensure the drugs are manufactured in compliance 
with Current Good Manufacturing Practice (CGMP) requirements.
    The ICH guidances for industry Q3A(R) Impurities in New Drug 
Substances (June 2008) and Q3B(R2) Impurities in New Drug Products 
(August 2006) provide recommendations on thresholds for the 
identification, reporting, and qualification of impurities and 
degradation products in new drug substances and drug products using 
drug substances that are produced by chemical synthesis. However, 
current guidances do not provide recommendations for the control of 
impurities and degradation products in fermentation and semi-synthetic 
products, including certain antibiotics manufactured from these 
processes. Antibiotics manufactured by fermentation or semi-synthesis 
are typically more complex than those produced solely by chemical 
synthesis, often containing a mixture of the active ingredient and 
impurities. The active ingredient is generally not a single molecular 
entity but rather a collection of structurally related, biologically 
active analogs that together define the active ingredient. To address 
this gap, the draft guidance provides recommendations on the 
identification, qualification, and control of impurities and 
degradation products in fermentation-based and semi-synthetic 
antibiotics. The principles described in ICH Q3A(R), ICH Q3B(R2), and 
ICH M7(R2) should apply to antibiotics manufactured by fermentation and 
semi-synthesis. Antibiotic drugs that have United States Pharmacopeia 
(USP) monographs must meet the requirements outlined in the respective 
USP monographs for the drug substance and the drug product (section 
501(b) of the FD&C Act).
    The draft guidance is being issued consistent with FDA's good 
guidance practices regulation (21 CFR 10.115). The draft guidance, when 
finalized, will represent the current thinking of FDA on ``Establishing 
Impurity Specifications for Antibiotics.'' It does not establish any 
rights for any person and is not binding on FDA or the public. You can 
use an alternative approach if it satisfies the requirements of the 
applicable statutes and regulations.
    As we develop final guidance on this topic, FDA will consider 
comments on costs or cost savings the guidance may generate, relevant 
for Executive Order 14192.

II. Paperwork Reduction Act of 1995

    While this guidance contains no collection of information, it does 
refer to previously approved FDA collections of information. The 
previously approved collections of information are subject to review by 
the Office of Management and Budget (OMB) under the Paperwork Reduction 
Act of 1995 (PRA) (44 U.S.C. 3501-3521). The collections of information 
in 21 CFR parts 210 and 211 pertaining to CGMP requirements have been 
approved under OMB control number 0910-0139. The collections of 
information in 21 CFR parts 312 and 314 have been approved under OMB 
control numbers 0910-0014 and 0910-0001, respectively. The collections 
of information pertaining to 21 CFR part 201 Subpart C pertaining to 
over-the-counter drug product labeling have been approved under OMB 
control number 0910-0340.

III. Electronic Access

    Persons with access to the internet may obtain the draft guidance 
at either https://www.fda.gov/drugs/guidance-compliance-regulatory-information/guidances-drugs, https://www.fda.gov/regulatory-
information/search-fda-

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guidance-documents, or https://www.regulations.gov.

Grace R. Graham,
Deputy Commissioner for Policy, Legislation, and International Affairs.
[FR Doc. 2026-07629 Filed 4-17-26; 8:45 am]
BILLING CODE 4164-01-P