NADA 049-287

A. DOSAGE FORM Medicated Feed

B. ROUTE OF ADMINISTRATION Oral

C. RECOMMENDED DOSAGES:

Dosage Indication for use

CHICKENS

10-50 g/t Broiler/fryer chickens: For an 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
Do not feed to chickens producing eggs for human consumption. Zero-day withdrawal period.

500 g/t Reduction of mortality due to Escherichiacoli infections susceptible to chlortetracycline.
(Feed for 5 days)

WARNING
Do not feed to chickens producing eggs for human consumption. Withdraw 24 hours prior to slaughter.

TURKEYS

10-50 g/t Growing turkeys: For an increased rate of weight gain and improved feed efficiency.

200 g/t Control of infectious synovitis caused by Mycoplasmasynoviae susceptible to chlortetracycline.
(Feed continously for 7 to 14 days)

400 g/t Control of hexamitiasis caused by Hexamitameleagrides susceptible to chlortetracycline.
(Feed continuously for 7 to 14 days)
Turkey poults not over 4 weeks of age: Reduction of mortality due to paratyphoid caused by Salmonella typhimurium susceptible to chlortetracycline.

25 mg/pound body weight daily Control of complicating bacterial organisms associated with bluecomb (transmissible enteritis, coronaviral enteritis) susceptible to chlortetracycline.
(Feed continuouoly for 7 to 14 days)

WARNING
Do not feed to turkeys producing eggs for human consumption. Zero-day withdrawal period.

SWINE

10-50 g/t Growing swine: For an increased rate of weight gain and improved feed efficiency.

50-100 g/t Reducing the incidence of cervical lymphadenitis (jowl abscesses) caused by Group EStreptococci susceptible to chlortetracycline.

400 g/t Breeding swine: Control of leptospirosis (reducing the instances of abortion and shedding of leptospirae) caused by Leptospirapomona susceptible to chlortetracycline.
(Feed continuously for 14 days)

10 mg/lb body weight daily Treatment of bacterial enteritis caused by Escherichiacoli and Salmonellacholeraesuis and bacterial pneumonia caused by caused Pasteurellamultocida susceptible to chlortetracycline.
(Feed for not more than 14 days)

WARNING
Zero-Day Withdrawal period.

SHEEP

20-50 g/t Growing sheep: For an increased rate of weight gain and improved feed efficiency.

80 mg/head/day Breeding sheep: Reducing the incidence of (vibrionic) abortion caused by Campylobacterfetus infection susceptible to chlortetracycline.

WARNING
Zero-day withdrawal period.

CALVES, BEEF CATTLE, AND NON-LACTATING DAIRY CATTLE

WARNING
A WITHDRAWAL PERIOD HAS NOT BEEN ESTABLISHED FOR THIS PRODUCT IN PRE-RUMINATING CALVES. DO NOT USE IN CALVES TO BE PROCESSED FOR VEAL.

0.1 mg/pound body weight daily Calves(up to 250 lbs.): For an increased rate of weight gain and improved feed efficiency.

25-70 mg/head/day Calves(250-400 lbs.): For an increased rate of weight gain and improved feed efficiency.

70 mg/head/day Growing cattle(over 400 lbs.): For an increased rate of weight gain, improved feed efficiency and reduction of liver condemnation due to liver abscesses.

WARNING
Zero-day withdrawal period

350 mg/head/day Cattle: Control of bacterial pneumonia associated with shipping fever complex caused by Pasteurella spp. susceptible to chlortetracycline.

350 mg/head/day Beef cattle(under 700 lbs.): Control of active infection of anaplasmosis caused by Anaplasmamarginale susceptible to chlortetracycline.

0.5 mg/pound daily Beef cattle(over 700 lbs.): Control of active infection of anaplasmosis caused by Anaplasmamarginale susceptible to chlortetracycline.

WARNING
Withdraw 48 hours prior to slaughter.

10 mg/pound body weight daily For calves, beef, and non-lactating dairy cattle:
Treatment of bacterial enteritis caused by Escherichiacoli and bacterial pneumonia caused by Pasteurellamultocida organisms susceptible to chlortetracycline. (Treat for not more than 5 days)

WARNING
Withdraw 10 days prior to slaughter.

IV. EFFECTIVENESS:

The drug was the subject of National Academy of Science/National Research Council (NAS/NRC) reports which were published in the FEDERAL REGISTER of July 21, 1970 (35 FR 11647). The Academy evaluated these products as probably effective for growth promotion and feed efficiency and the treatment of animal diseases caused by pathogens sensitive to chlortetracycline.

The Academy states that: (1) Claims made regarding "for prevention of" or "to prevent" should be replaced with "as an aid in the control of" or "to aid in the control of"; (2) claims for growth promotion or stimulation are disallowed and claims for faster gains and/or feed efficiency should be stated as "may result in faster gains and/or improved feed efficiency under appropriate conditions"; (3) each disease claim should be properly qualified as "appropriate for use in (name of disease) caused by pathogens sensitive to (name of drug) "; if the disease cannot be so qualified the claim must be dropped; (4) claims pertaining to egg production and hatchability should be changed to "May aid in maintaining egg production and hatchability, under appropriate conditions, by controlling pathogenic microorganisms"; (5) the labels should warn that treated animals must actually consume enough medicated water or medicated feed to provide a therapeutic dosage under the conditions that prevail and, as a precaution, state the desired oral dose per unit of animal weight per day for each species as a guide to effective usage of the preparation in drinking water or feed: and (6) effective blood levels are required for each recommended dosage.

The Food and Drug Administration concurs with the Academy's findings, interpreting the phrase "...cannot be so qualified..." in paragraph (3) to mean "...is not supported by adequate data..." (See Fed. Reg. vol. 35, No. 140-Tues., July 21, 1970). FDA proceeded to review all available data relating to the effectiveness of products subject to NADA 49-287 to determine which label claims were supported by the requisite proof of effectiveness. That review resulted in a letter to the sponsor dated April 20, 1992, in which the agency stated that it had concluded that such data supported effectiveness only for the control and treatment of certain bacterial diseases susceptible to chlortetracycline hydrochloride in chickens, turkeys, calves, cattle, sheep and swine, and for the increased rate of weight gain and the improved feed efficiency with same species.

Thereafter, the sponsor complied with the evaluation of NAS/NRC and FDA's conclusions in the following manner:

Appropriate oral doses for all the allowable species and claims based on milligrams per unit of body weight or grams per ton are on the current labels.
Claims pertaining to egg production and hatchablilty have been deleted
from the labels.
Each disease claim on the label has been properly qualified with the appropriate genus and species of bacteria susceptible to chlortetracycline hydrochloride. Disease claims which were not so qualified have been deleted.
Claims made for prevention have been revised to read "Control of..." where appropriate.
Claims for growth promotion or stimulation have been removed. Allowable claims are for increased rate of weight gain and improved feed efficiency.

V. ANIMAL SAFETY:

This supplemental NADA satisfies the requirements of section 512 of the Act and demonstrates that PFICHLOR Type A Medicated Article when used under its proposed conditions of use, is safe and effective for the labeled indications. The approval provides for use of PFICHLOR Type A Medicated Article for the control and treatment of specific diseases in swine, cattle, calves, chickens, turkeys, and sheep, and for the increased rate of weight gain and improved feed efficiency with same species.

The "probably effective" finding of the NAS/NRC regarding chlortetracycline hydrochloride which was published in the FEDERAL REGISTER of July 21, 1970, was subsequently reviewed by FDA, resulting in the upgrade to "effective" status with respect to the claims noted in the paragraphs above. The firm submitted revised labeling to conform and, therefore, this supplemental NADA complies with the NAS/NRC evaluation and FDA's conclusions.

When NADA 49-287 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)), 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 and, therefore, did not require a re-evaluation of the human food or target animal safety data in the parent application.

Under section 512(c)(2)(F)(iii) of the FFDCA, this approval for food producing animals does not qualify for marketing exclusivity because the supplemental application does not contain substantial evidence of the effectiveness of the drug involved, any studies of the animal safety, or, in the case of food producing animals, human food safety studies (other than bioequivalency or residue studies) required for the approval and conducted or sponsored by the applicant.

NADA	049-287
Sponsor:	Hoffmann-LaRoche Inc. Nutley, NJ 07110
Generic Name:	Pfichlor Chlortetracycline Pre-mix
Trade Name:	Type A Medicated Article
Marketing Status:	Over the Counter (OTC)
Effect of Supplement:	Category II change.