[Federal Register Volume 89, Number 138 (Thursday, July 18, 2024)]
[Notices]
[Pages 58383-58384]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2024-15812]


-----------------------------------------------------------------------

DEPARTMENT OF HEALTH AND HUMAN SERVICES

Food and Drug Administration

[Docket No. FDA-2022-D-0113]


Clinical Pharmacology Considerations for Human Radiolabeled Mass 
Balance Studies; Guidance for Industry; Availability

AGENCY: Food and Drug Administration, HHS.

ACTION: Notice of availability.

-----------------------------------------------------------------------

SUMMARY: The Food and Drug Administration (FDA or Agency) is announcing 
the availability of a final guidance for industry entitled ``Clinical 
Pharmacology Considerations for Human Radiolabeled Mass Balance 
Studies.'' This guidance describes FDA's recommendations regarding 
clinical pharmacology considerations for conducting human radiolabeled 
mass balance studies, including deciding whether and when to conduct 
the study, designing the study, and reporting results.

DATES: The announcement of the guidance is published in the Federal 
Register on July 18, 2024.

ADDRESSES: You may submit either electronic or written comments on 
Agency guidances 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-2022-D-0113 for ``Clinical Pharmacology Considerations for Human 
Radiolabeled Mass Balance Studies.'' 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

[[Page 58384]]

with a heading or cover note that states ``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.govinfo.gov/content/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 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 guidance document.

FOR FURTHER INFORMATION CONTACT: Anuradha Ramamoorthy, Center for Drug 
Evaluation and Research, Food and Drug Administration, 10903 New 
Hampshire Ave., Silver Spring, MD 20903, 
[email protected], 240-402-6426.

SUPPLEMENTARY INFORMATION:

I. Background

    FDA is announcing the availability of a guidance for industry 
entitled ``Clinical Pharmacology Considerations for Human Radiolabeled 
Mass Balance Studies.'' A human radiolabeled mass balance study is the 
single most direct study to obtain quantitative and comprehensive 
information on the absorption, distribution, metabolism, and excretion 
of an investigational drug in the human body. The mass balance study 
can provide information to determine the overall pathways of metabolism 
and excretion of an investigational drug, identify circulating 
metabolites, and determine the abundance of metabolites relative to the 
parent or total drug-related exposure. This guidance provides FDA's 
recommendations for clinical pharmacology considerations in conducting 
human radiolabeled mass balance studies during drug development, 
including: (1) deciding whether and when to conduct the study, (2) 
designing the study, and (3) reporting the study results.
    This guidance finalizes the draft guidance of the same name issued 
on May 5, 2022 (87 FR 26763). FDA considered comments received on the 
draft guidance as the guidance was finalized. Changes from the draft to 
the final guidance include: (1) updates to terms used in the guidance 
to provide clarity, (2) additional references that have been published 
since the draft guidance was issued, and (3) editorial changes to 
improve clarity.
    This guidance is being issued consistent with FDA's good guidance 
practices regulation (21 CFR 10.115). The guidance represents the 
current thinking of FDA on ``Clinical Pharmacology Considerations for 
Human Radiolabeled Mass Balance Studies.'' 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.

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 201.57 relating to prescription product labeling requirements 
have been approved under OMB control number 0910-0572. The collections 
of information for submission of investigational new drug applications 
in 21 CFR part 312 have been approved under OMB control number 0910-
0014. The collections of information for submission of new drug 
applications in 21 CFR part 314 have been approved under OMB control 
number 0910-0001.

III. Electronic Access

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

    Dated: July 15, 2024.
Lauren K. Roth,
Associate Commissioner for Policy.
[FR Doc. 2024-15812 Filed 7-17-24; 8:45 am]
BILLING CODE 4164-01-P