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Redbook 2000: IV.C.7. Combined Chronic Toxicity/Carcinogenicity Studies with Rodents July 2007

Issued by:
Guidance Issuing Office
Center for Food Safety and Applied Nutrition, Office of Food Additive Safety

Toxicological Principles for the Safety Assessment of Food Ingredients

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This guidance represents the Food and Drug Administration's (FDA's) current thinking on this topic. It does not create or confer any rights for or on any person and does not operate to bind FDA or the public. You can use an alternative approach if the approach satisfies the requirements of the applicable statutes and regulations. If you want to discuss an alternative approach, contact the FDA staff responsible for implementing this guidance. If you cannot identify the appropriate FDA staff, call the appropriate number listed on the title page of this guidance.

This section of Redbook 2000 supersedes the 1993 "draft" Redbook Chapter IV.C.7. The FDA acknowledges that it is complicated and difficult to conduct a combined chronic toxicity/carcinogenicity rodent study particularly with an in-utero exposure phase. This is often due to difficulty in setting and administering appropriate dose levels for both types of studies concurrently. Additionally, the general objectives of these two types of studies are different. Nevertheless, when pre-chronic studies provide reasonable estimates of toxicity to predict the information (i.e., treatment doses) to be used in a single bioassay, a chronic toxicity study may be combined with a carcinogenicity study and reveal information about an ingredient's potential to be a carcinogen as well as the maximum dose that produces no adverse effects.

The FDA recommends that the petitioner/notifier consult with the FDA before conducting a combined study. Sponsors/submitters of petitions/notifications are also encouraged to become familiar with the Guidance for Chronic Toxicity Studies with Rodents (Chapter IV.C.5.a.), Carcinogenicity Studies with Rodents (Chapter IV.C.6.), In-Utero Exposure Phase for Addition to Carcinogenicity Studies or Chronic Toxicity Studies with Rodents (Chapter IV.C.8.), Reporting Results of Toxicity Studies (Chapter IV.B.2.), Pathology Considerations in Toxicity Studies (Chapter IV.B.3.), and Statistical Considerations in Toxicity Studies (Chapter IV.B.4.) during the development of study design.

Submit Comments

Submit comments on this guidance document electronically via docket ID: FDA-2013-S-0610 - Specific Electronic Submissions Intended For FDA's Dockets Management Staff (i.e., Citizen Petitions, Draft Proposed Guidance Documents, Variances, and other administrative record submissions)

If unable to submit comments online, please mail written comments to:

Dockets Management
Food and Drug Administration
5630 Fishers Lane, Rm 1061
Rockville, MD 20852

All comments should be identified with the title of the guidance.

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