FDA Announces Public Hearing on Scientific Data and Information Related to the Residue of Carcinogenic Concern for the New Animal Drug Carbadox

January 12, 2022

The Food and Drug Administration will hold a public hearing on Scientific Data and Information Related to the Residue of Carcinogenic Concern for the New Animal Drug Carbadox, a carcinogenic new animal drug used in swine feed. The public hearing will be held virtually on March 10, 2022, via Zoom from 1:00 to 5:00 p.m. ET.

Under the Delaney Clause (section 512(d)(1)(I)) of the Food, Drug, and Cosmetic Act (FD&C Act), the FDA generally cannot approve an application for a carcinogenic new animal drug. An exception to this general rule is commonly known as the Diethylstilbestrol “DES” Proviso, which allows for the approval of a carcinogenic new animal drug where the FDA finds that under the approved conditions of use: (1) The drug will not adversely affect the animals treated with the drug; and (2) no residues of the drug will be found by an approved regulatory method in any edible tissues of, or in any foods yielded by, the animal.

On July 20, 2020, the Agency published a notice in the Federal Register proposing an order to revoke the approved method for detecting residues of carbadox. The currently approved method measures quinoxaline-2-carboxylic acid (QCA) as a marker residue to detect the presence of the residue of carcinogenic concern . The proposal to revoke the approved method for carbadox is based on CVM’s determination that the method is inadequate to monitor the residue of carcinogenic concern in compliance with FDA's regulations (21 CFR part 500, subpart E). These regulations set out the requirements for demonstrating that no residues of the drug will be found by an approved regulatory method in any edible tissues of or in any foods obtained from the animal, as required to meet the requirements of the DES Proviso. The purpose of the public hearing is to gather additional data and information related to the residue of carcinogenic concern for the new animal drug carbadox.

A presiding officer will conduct the hearing, accompanied by other employees of the United States government serving as a panel.

The FDA encourages public comments and presentations at the public hearing. The FDA is particularly interested in receiving comments, data, and information about the topics listed in the Federal Register Notice. To attend the virtual public hearing, please register at https://fda.zoomgov.com/j/1600135012?pwd=MFdjMW9FRXg4RGllc3FHWVhkWVAyZz09 by March 9, 2022. Please provide complete contact information for each attendee, including name, title, affiliation, address, email, and telephone.

During online registration, you may indicate if you wish to make a formal presentation (with accompanying slide deck) or present oral comments during the public hearing session (with no slide deck) and which topic(s) you would like to address. The deadline to register to give a presentation is February 18, 2022.

In addition to holding the hearing, the FDA has opened a docket and is accepting electronic or written comments through April 11, 2020. To electronically submit comments to the docket, visit www.regulations.gov and type FDA-2021-N-1326 in the search box. To submit comments to the docket by mail, follow the instructions in the Federal Register Notice.

For more information:

Issued by FDA Center for Veterinary Medicine.
For questions, Contact CVM.