Approval Date: October 26, 1998
Freedom of Information Summary
NADA 048-761
I. GENERAL INFORMATION:
NADA 048-761 Sponsor: Roche Vitamins, Inc.
Parsippany, NJ 07054
Generic Name: Chlortetracycline Trade Name: Aureomycin Type A Medicated Article Marketing Status: Over the Counter (OTC) Effect of Supplement: Changes the withdrawal time from 24 hours to zero (0) day withdrawal when chlortetracycline is fed to chickens at 500 g/ton of feed for 5 days for reduction of mortality due to Escherichia coli infections susceptible to chlortetracycline. 2. INDICATIONS FOR USE: See below
3. A. DOSAGE FORM: Type A Medicated Article
B. ROUTE OF ADMINISTRATION: Oral - For use in Type C medicated chicken feeds.
C. Recommended DOSAGES:
Dosage Dosage CHICKENS 10-50 g/t Broiler/fryer chickens: For increased rate of weight gain and improved feed efficiency.
100-200 g/t
Control of infectious synovitis caused by Mycoplasmasynoviae susceptible to chlortetracycline.
(Feed continuously for 7 to 14 days )200-400 g/t Control of chronic respiratory disease (CRD) and air sac infection caused by Mycoplasmagallisepticum and Escherichiacoli susceptible to chlortetracycline.
(Feed continuously for 7 to 14 days)WARNING
Zero-day withdrawal period.
500 g/t Reduction of mortality due to Escherichiacoli infections susceptible to chlortetracycline.
(Feed for 5 days)WARNING
Zero-day withdrawal period.
4. EFFECTIVENESS: No further effectiveness data were required.
5. ANIMAL SAFETY: No further safety data were required.
6. HUMAN FOOD SAFETY:
A. Safe Concentrations of Total Residues
Recently, the Center for Veterinary Medicine (CVM) revised the tolerances for tetracycline drugs (61 FR 67453 ). Based on that reevaluation, tolerances for total tetracycline residues in tissues are establishes as follows:
2 ppm in muscle
6 ppm in liver
12 ppm in kidney
12 ppm in fat
0.4 ppm in eggsB. Studies to Establish a Withdrawal Time
I. Study # A-62-5-FT
Investigator:
J. J. Drain, American Cyanamid Company,
Princeton, NJ 08543-0400
Objective:
To study the magnitude of chlortetracycline (CTC) residues in chicken blood and tissues following high level dietary supplementation at 800, 1200, 1600, and 2000 g/ton for 5 days.
Summary and Conclusions:
One hundred and fifty ten-week-old broilers were fed low calcium diets containing 0, 800, 1200, 1600 and 2000 gms. chlortetracycline per ton of feed. Period of medication was five days. CTC concentrations of blood and tisues were determined by microbiological assay. Five birds were utilized for each treatment at each sampling (0-day, 1-day, 3-days, 6-days, 8-days and 120 days of withdrawal). All tissues from all control birds were negative (less than 0.025 mcg CTC/gm tissue) for CTC. Only data from birds fed 800 gm CTC/ton of feed are summarized in Table below:
Concentration (ppm) of chlortetracycline (CTC) in edible tissue of chickens following identified withdrawal period after treatment with 800 gms CTC per ton of feed for 5 days.
R E S I D U E S OF CTC (PPM) IN
DAY OF WITHDRAWAL
MUSCLE
FAT
LIVER
KIDNEY
0
0.38
0.09
0.90
6.44
1
0.01
Neg.*
0.02
0.16
3
Neg.
Neg.
0.01
0.12
6
Neg.
Neg.
Neg.
0.08
8
Neg.
Neg.
Neg.
0.07
10
Neg.
Neg.
Neg.
0.05
* Negative indicates value of less than 0.025 mcg CTC/gm tissue
C. Calculating the Withdrawal Time
All of the residues in both kidney and liver are less than the assigned tolerances for all slaughter points. The calculated 99th percentile/95% confidence limit for liver residues at zero withdrawal is significantly less than the 6 ppm tolerance for liver residues.D. Regulatory Analytical Methods for Residues
The regulatory analytical method for detection of residues of the drug is a microbiological test using Bacillus cereus var mycoides (ATCC 11778). The method is found in Antibiotic Residues in Milk, Dairy Products, and Animal Tissues: Methods, Reports and Protocols, Revised October 1968, Reprinted December 1974, Nation Center for Antibiotic and Insulin Analysis, FDA, Washington, DC 20204.
7. AGENCY CONCLUSIONS:
This supplemental NADA satisfies the requirements of section 512 of the Act and demonstrates that AUREOMYCIN Type A Medicated Article when used under its proposed conditions of use, is safe and effective for the labeled indications. The supplemental approval provides for the use of this chlortetracycline premix fed to chickens at 500 g/ton of feed for 5 days for reduction of mortality due to Eschericha coli infections with a zero-day withdrawal time.
The "probably effective"finding of the NAS/NRC/DESI regarding chlortetracycline hydrochloride was published in the FEDERAL REGISTER of July 21, 1970, subsequently reviewed by FDA, resulting in the upgrade to "effective status" and was DESI-finalized and codified in the FEDERAL REGISTER on July 9, 1996.
When NADA 48-761 was reviewed under NAS/NRC/DESI program, it was an over-the-counter product and this marketing status remains unchanged. Other Chlortetracycline Type A Medicated Articles for use in food-producing animals are also currently on the market as over-the-counter products. Therefore, the Center for Veterinary Medicine has concluded that this product should retain over-the-counter marketing status.
Under the Center's supplemental approval policy [21 CFR 514.106(b)(2)(x)] this is a Category II change. The approval of this change is not expected to have any adverse effect on the safety or effectiveness of this new animal drug. However, the approval did require a re-evaluation of the human food safety data in the parent application.
8. Labeling: See Attachment(s)
Aureomycin® 50, 90, and 100 premix bags