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U.S. Department of Health and Human Services

Animal & Veterinary

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NADA 130-951 Stenorol® - supplemental approval (September 19, 1994)

Approval Date: September 19, 1994

I. GENERAL INFORMATION:

NADA 130-951
Sponsor: Roussel-Uclaf
P. 0. Box 2500
Route 202-206
Somerville, New Jersey 08876-1258
Generic Name: halofuginone hydrobromide
Trade Name: STENOROL®
Marketing Status: Over the Counter (OTC)
Effect of Supplement: This supplemental submission has been filed to provide for the same dose level of 2.72 g/t (3 ppm) to be fed to replacement cage laying chickens and replacement broiler breeder chickens for the prevention of coccidiosis caused by Eimeria tenella, E. necatrix, E. aacervulina, E. maxima, E. brunetti, and E. mivati / mitis.

II. INDICATIONS FOR USE:

The original approval for this NADA provided for the use of halofuginone hydrobromide in complete feeds for broiler chickens for the prevention of coccidiosis. This supplemental submission has been filed to provide for the same dose level of 2.72 g/t (3 ppm) to be fed to replacement cage laying chickens and replacement broiler breeder chickens for the prevention of coccidiosis caused by Eimeria tenella, E. necatrix, E. aacervulina, E. maxima, E. brunetti, and E. mivati / mitis.

III. DOSAGE FORM, ROUTE OF ADMINISTRATION AND RECOMMENDED DOSAGE:

STENOROL® is marketed as a Type A medicated article (premix). The halofuginone hydrobromide type A medicated article is sold in one concentration: 2.72 grams halofuginone hydrobromide activity per pound (6 grams per kilogram of premix).

Dosage and Administration:

The route of administration of the drug is oral via the feed. Halofuginone hydrobromide is added to replacement cage layer complete feed and replacement broiler breeder complete feed at a concentration of 2.72 g/ton. The resultant feed containing the drug is then fed continuously as the sole ration. Halofuginone hydrobromide must be withdrawn from replacement cage layer feed at 20 weeks of age. Halofuginone hydrobromide must be withdrawn from replacement broiler breeder feed at 16 weeks of age. If the replacement cage layers and broiler breeders are sold for slaughter, halofuginone hydrobromide must be withdrawn 4 days before slaughter.

IV. EFFECTIVENESS:

A. Pivotal Battery Confirmation Study:

The efficacy data for halofuginone hydrobromide in broiler chickens is located in its parent NADA and the FOI contains a summary of the data (NADA 130-951 - 50 FR 33718 - August 21, 1985). The efficacy data from eighteen pivotal battery confirmation studies contained in the parent NADA 130-951 demonstrates effectiveness of halofuginone hydrobromide in broiler chickens and in broiler breeder chickens.

In addition to the broiler chicken battery confirmation studies contained in the parent NADA 130-951 which correspondingly demonstrate effectiveness in replacement broiler breeders, this supplement to an approved application contains an adequate and well controlled battery study demonstrating the effectiveness of halofuginone hydrobromide when fed to replacement female cage laying chickens. An investigation using recent field isolates from broiler producing regions in the United States was carried out in batteries to prove the effectiveness of halofuginone against 6 pathogenic coccidia of chickens. The investigator conducted an experiment in two phases (Study 1 and Study 2) involving recent field strain isolates of coccidia: Eimeria tenella, E. necatrix, E. acervulina, maxima, E. brunetti, and E. mivati / E. mitis . The battery study for the effectiveness claim was conducted by Dr. Carey Quarles, Colorado Quality Research, Inc. 1401 Duff Drive, Suite 700, Fort Collins, Colorado 80524.

Study No. - 1566-01-02-93 (CQR #HRD-93-B1)
Starting/End Date - February 26 to April 1, 1993
Identification of Substance and Dosage Form - STENOROL® 2.72 g/lb
Species and Age - Female Leghorn chickens, 2 weeks at study start
Number of Chicks - 60
Drug Level Tested - 2.72 g/t (3 ppm)
Route of Administration - Fed orally in diet

The experimental groups were: Infected medicated, unmedicated uninfected and unmedicated infected. Oral infections with speculated oocysts ranged from moderate to severe with clinical signs and pathology characteristic of the Eimeria species employed. The investigation was conducted using a strain of cage laying chickens that are commonly available in the given areas. The chickens were approximately two weeks of age when the investigation was started. The parameters were weight gain, feed efficiency, mortality due to coccidiosis, lesion scores, droppings (fecal) scores, and oocysts passage counts. The following Tables 1 through 7 are the result of pooling the data by species.

A total of 960 Leghorn female chickens were used in the trial to demonstrate the effectivencss and safety of halofuginone hydrobromide.The chicks were randomly assigned to treatment and cage level within a battery. Treatment assignment to batteries was preselected based on treatment and cage level within a battery. Uninfected controls were maintained in the top battery decks to prevent accidental infection and consumption of medicated feed. Each treatment consisted of six replicates of ten female chicks each. The study was conducted in two phases to test all single Eimeria species and mixed species (Study 1 and Study 2).

Prevention of mortality, reduction of lesion scores and reduction of fecal scores are the major parameters used to demonstrate anticoccidial effectiveness. Examination of the data presented in Tables 1 through 7 demonstrates a reduction in mortality, lesions scores, and fecal scores compared with the unmedicated infected control. Weight gain and feed efficiency for the medicated groups were better than the unmedicated infected controls.

(Eds. note: The following 2 tables consist of 6 columns each.)

STUDY 1

TABLE 1: THE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDE AT 3 PPM WHEN REPLACEMENT CAGE LAYER (LEGHORN) CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE BY E. TENELLA 

                Ave.Wt.1      Adjusted         %          Lesion     Fecal 
Treatment     Gain/Pen(g)D6   Feed/Gain    Mortality2    Scores3    Scores4  
Uninfected         848               2.041            0                0            0 
Infected            92               5.391           15             3.45         3.52 
Medicated          750               2.036            0             1.03         0.5 

TABLE 2: THE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDE AT 3 PPM WHEN LEGHORN CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE BY E. ACERVULINA

                Ave.Wt.1      Adjusted         %          Lesion     Fecal 
Treatment     Gain/Pen(g)D6   Feed/Gain    Mortality2    Scores3    Scores4
Uninfected         848               2.041            0                0            0  
Infectcd           540               3.080            0             2.88         1.58 
Medicated          720               2.310            0             0.37         0.67 

1 Six days after infection

2 Due to coccidiosis

3 Average total lesion score is based on the following system for scoring four sections of the gastrointestinal tract: 0 = Normal; 1 = Slight lesions; 2 = Moderate lesions; 3 = Severe lesions; 4 = Extremely severe lesions. Average total lesion scores above are calculated by adding average scores from the upper, middle, lower, and cecal sections of the gastrointestinal tract, and therefore, can exceed a score of 4.

4 Average fecal score is based on the following system: O = Normal; 1 = Slightly wet; 2 = Moderately wet; 3 = Wet; 4 = Very Wet

(Eds. note: The following 3 tables consist of 6 columns each.)

TABLE 3: THE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDE AT 3 PPM WHEN LEGHORN CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE BY E. MAXIMA

                Ave.Wt.1      Adjusted         %          Lesion     Fecal 
Treatment     Gain/Pen(g)D6   Feed/Gain    Mortality2    Scores3    Scores4  
Uninfected         848               2.041            0                0            0
Infected           376               3.328          6.7             4.35         2.5
Medicated          743               2.266            0             1.43         0.75 

TABLE 4: THE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDE AT 3 PPM WHEN LEGHORN CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE BY ALL MIXED EIMERIA SPP. INFECTION (E. tenella, E. acervulina, E. maxima, E. necatrix, E. mivati / mitis, and E. brunetti)

                Ave.Wt.1      Adjusted         %          Lesion     Fecal 
Treatment     Gain/Pen(g)D6   Feed/Gain    Mortality2    Scores3    Scores4  
Uninfected         848               2.041            0                0            0
Infected           475               2.985          6.7             6.13         2.83
Medicated          760               2.251            0             2.12         0.92

STUDY 2

TABLE 5: TIlE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDIE AT 3 PPM WHEN LEGHORN CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE BY E. NECATRIX

  
                Ave.Wt.1      Adjusted         %          Lesion     Fecal 
Treatment     Gain/Pen(g)D6   Feed/Gain    Mortality2    Scores3    Scores4
Uninfected 638 1.997 1.73 0 0 Infected -31 4.868 30 4.34 3.17 Medicated 626 2.114 0 1.63 0.58

1 Six days after infection

2 Due to coccidiosis

2 Other causes

4 Average total lesion score is based on the following system for scoring four sections of the gastrointestinal tract: 0 = Normal; 1 = Slight lesions; 2 = Moderate lesions; 3 = Severe lesions; 4 = Extremely severe lesions. Average total lesion scores above are calculated by adding average scores from the upper, middle, lower, and cecal sections of the gastrointestinal tract, and therefore, can exceed a score of 4.

5 Average fecal score is based on the following system: O = Normal; 1 = Slightly wet; 2 = Moderately wet; 3 = Wet; 4 = Very Wet

(Eds. note: The following 2 tables consist of 6 columns each.)

TABLE 6: THE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDE AT 3 PPM WHEN LEGHORN CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE B Y E. MIVATI E. MITIS

  
                Ave.Wt.1      Adjusted         %          Lesion     Fecal 
Treatment     Gain/Pen(g)D6   Feed/Gain    Mortality2    Scores4    Scores5  
Uninfected         638               1.997          1.73               0            0
Infected           599               2.601            0             3.78         2.25
Medicated          645               2.018            0             1.3          1.08

TABLE 7: THE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDE AT 3 PPM WHEN LEGHORN CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE BY E. BRUNE7TI

                Ave.Wt.1      Adjusted         %          Lesion     Fecal 
Treatment     Gain/Pen(g)D6   Feed/Gain    Mortality2    Scores4    Scores5
Uninfected         638               1.997          1.73               0            0
Infected           386               2.636          6.7             2.79         2.17
Medicated          651               2.465            0             1.05         0.67

1 Six days after infection

2 Due to coccidiosis

3 Other causes

4 Average total lesion score is based on the following system for scoring four sections of the gastrointestinal tract: 0 = Normal; 1 = Slight lesions; 2= Moderate lesions; 3=Severe lesions; 4 = Extremely severe lesions. Average total lesion scores above are calculated by adding average scores from the upper, middle, lower, and cecal sections of the gastrointestinal tract, and therefore, can exceed a score of 4.

5 Average fecal score is based on the following system: O = Normal; 1 = Slightly wet; 2 = Moderately wet; 3 = Wet; 4 = Very Wet

CONCLUSION:

Halofuginone hydrobromide at 3 ppm was effective in reducing mortality, lesion scores, and fecal scores when compared with the unmedicated infected control birds.

B. Pivotal Floor-Pen Study:

The floor-pen study for the effectiveness claim in replacement cage laying and replacement broiler breeder chickens was conducted by: D. Carey Quarles, Colorado Quality Research, Inc., 1401 Duff Drive, Suite 700, Fort Collins, Colorado 80524.

Study No. - CQR #HRG-87-21
Starting Date - November 30, 1987
End Date - January 25, 1988
Identification of Substance and Dosage Form - STENOROL® premix, 2.72 g/lb
Species and Age - Female SCW Leghorn chickens (600), Female Arbor Acres X Arbor Acres broiler breeders (600), 1 day of age
Number of Chicks - 1,200
Drug Level Tested - 3 ppm
Route of Administration - Fed orally in diet
Treatments - Infected control, infected treated

Replacement Cage Layer Chickens:

To confirm the effectiveness of halofuginone hydrobromide in replacement cage laying chickens, a floor-pen study was conducted under conditions of simulated actual use. Mixed Eimeria spp. oocysts from different broiler producing regions of the United States were used in the study. Treatments were randomly assigned to pens within a block, and sixty female Leghorn were randomly assigned to a pen. Each of two treatments were replicated five times, and 600 Leghorn birds were used. An unmedicated infected group was the control which represented one treatment, and a medicated infected group represented the second treatment at 2.72 g/t. Chickens were exposed to coccidia (mixed Eimeria spp.) challenge via the feed. Medication was fed continuously from day 1 until the termination of the study at 56 days of age. Table 8 summarizes the cage laying chicken data from the study.

Replacement Broiler Breeder Chickens:

To confirm tile effectiveness of halofuginone hydrobromide in replacement broiler breeder chickens, a floor-pen study was conducted under conditions of simulated actual use. Mixed Eimeriar spp. oocysts from different broiler producing regions of the United States were used in the study. Treatments were randomly assigned to pens within a block, and 60 broiler breeder females were randomly assigned to a pen. Each of two treatments were replicated five times, and 600 broiler breeder females were used. An unmedicated infected group was the control which represented one treatment, and a medicated infected group represented the second treatment at 2.72 g/t. Chickens were exposed to coccidia (mixed Eimeria spp.) challenge via the feed. Medication was fed continuously from day 1 until the termination of the study at 56 days of age. Table 9 summarizes the broiler breeder data from the study.

(Eds. note: The following table consists of 5 columns.)

TABLE 8: THE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDE AT 3 PPM WHEN REPLACEMENT CAGE LAYER LEGHORN) CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE BY SIX MIXED EIMERA SPP.1

                                  Ave. Body       Adjusted     Lesion
Treatment       % Mortality 2     Weight(g)3      Feed/Gain4   Scores5 
 
Infected               10.60               439              4.79          3.12
Medicated               0.03               458              4.86          1.12 

1 Eimeria tenella, E. necatrix, E. acervulina, E. maxima, E. brunetti, and E. mivati / mitis.

2 Due to coccidiosis

3 Per survivor; 22 days post inoculation

4 14 days post inoculation

5 14 days post inoculation lesion scores. Based on the following system for scoring four sections of the gastrointestinal tract: 0 = Normal; 1 = Slight lesions; 2 = Moderate lesions; 3 = Severe lesions; 4 = Extremely severe lesions. Average total lesion scores above are calculated by adding average scores from the upper, middle, lower, and cecal sections of the gastrointestinal tract, and therefore, can exceed a score of 4.

(Eds. note: The following table consists of 5 columns.)

TABLE 9: THE COCCIDIOSIS EFFICACY OF HALOFUGINONE HYDROBROMIDE AT 3 PPM WHEN REPLACEMENT BROILER BREEDER CHICKENS WERE SUBJECTED TO COCCIDIA CHALLENGE BY SIX MIXED EIMERIA SPP. 1

                                  Ave. Body       Adjusted     Lesion
Treatment       % Mortality 2     Weight(g)3      Feed/Gain4   Scores5 
Infectcd                4.32              1534              2.48          4.68
Medicated                  0              1531              2.26          1.40

1 Eimeria tenella, E. necatrix, E. acervulina, E. maxima, E. brunetti, and E. mivati / mitis.

2 Due to coccidiosis

3 Per survivor; 22 days post inoculation

4 14 days post inoculation

5 14 days post inoculation lesion scores. Based on the following system for scoring four sections of the gastrointestinal tract: 0 = Normal; 1 = Slight lesions; 2 = Moderate lesions; 3 = Severe lesions; 4 = Extremely severe lesions. Average total lesion scores above are calculated by adding average scores from the upper, middle, lower, and cecal sections of the gastrointestinal tract, and therefore, can exceed a score of 4.

CONCLUSION:

Efficacy was evaluated on the basis of coccidiosis induced mortality, lesion scores, body weight and feed efficiency. STENOROL at 3 ppm (2.72 g/t) effectively reduced mortality, intestinal lesion scores, and improved weight gain. Observations confirmed that there were no adverse drug effects, including no abnormal droppings and no wet litter.

C. Clinical Field Trials

The clinical field trials data for halofuginone hydrobromide in broiler chickens is located in its parent NADA and in the FOI Summary. (NADA 130-951 - 50 FR 33718 - August 21, 1985). The data from eight clinical trials and floor-pen trials demonstrates safety and effectiveness of halofuginone hydrobromide in broiler chickens, and replacement cage layer and broiler breeder chickens.

VII. TARGET ANIMAL SAFETY

The target animal safety data for halofuginone hydrobromide in broiler chickens is located in its parent NADA and the FOI contains a summary of the data (NADA 130-951 - 50 FR 33718 - August 21, 1985). The target animal safety data from an acute oral toxicity study and a well controlled floor-pen study contained in the parent NADA 130-951 demonstrate safety of the halofuginone hydrobromide in broiler chickens.

In addition to the broiler chicken target animal safety studies contained in the parent NADA 130-951, this supplement to an approved application contains an adequate and well controlled target animal safety study demonstrating the safety of halofuginone hydrobromide when fed to replacement cage laying chickens and replacement broiler breeder chickens.

The above effectiveness studies (Section 4) adequately demonstrated that there were no adverse effects when halofuginone hydrobromide at 3 ppm was included in the feed. However, further evaluation by Dr. Carey Quarles, Colorado Quality Research, Inc., Fort Collins, Colorado 80524, of the target animal safety of halofuginone hydrobromide was studied in a well controlled floor-pen study.

Study No. - CQR #HRG-87-32
Starting Date - June 29, 1987
End Date - November 18, 1987
Identification of Substance and Dosage Form - STENOROL® premix, 2.72 g/lb
Species and Age - Male and female W77-SCW Leghorn chickens (960), Male and female Arbor Acres A-1 broiler breeders (760), 1 day of age
Number of Chicks - 1,720
Drug Levels Tested - 0, 2.72, 8.16 and 13.60 g/t (0, 3, 9 and 15 ppm)
Route of Administration - Fed orally in diet

REPLACEMENT CAGE LAYER CHICKENS

(Eds. note: The following table consists of 6 columns.)

TABLE 10: TOASTY OF HALOFUGINOE HYDROBROMIDE IN REPLACEMENT CAGE LAYING CHICKENS WHEN FED AT 0, 3, 9 AND 15 PPM FROM ONE DAY OF AGE THROUGH 140 DAYS OF AGE 

Number of      Treatment            %         Body Weight       Feed
 Birds      ppm       (g/t)     Mortality*        (g)        Efficiency 
  240          0                        1.25             1448             5.51
  240          3         (2.72)         1.25             1395             6.04 
  240          9         (8.16)         1.25             1170             7.46 
  240         15        (13.60)         7.50             1023             8.62 
* Based on  240 birds/treatment

Although halofuginone hydrobromide is not intended for use in cage laying chickens in production, additional data were collected after the 140-day growing period to determine the effect of feeding halofuginone hydrobromide during the growing period on subsequent egg production and egg quality characteristics. Halofuginone hydrobromide was withdrawn from all diets at 140 days (Table 11).

(Eds. note: The following table consists of 7 columns.)

TABLE 11: TOXICITY OF HALOFUGINONE HYDROBROMIDE ON EGG PRODUCTION IN REPLACEMENT CAGE LAYING CHICKENS WHEN FED AT 0, 3, 9 AND 15 PPM FOR FOUR 28-DAY PERIODS 

                                                   Egg
Number of      Treatment           Egg          Production                     Egg Shell 
 Birds      ppm       (g/t)     Production 1    Efficiency 2    Egg Wt. 3     Thickness 4 
                                                  
  240          0                        9.63              1.72             56.68             0.32
  240          3         (2.72)        10.60              1.67             57.25             0.32
  240          9         (8.16)        10.31              1.75             57.25             0.32
  240         15        (13.60)         8.17              2.03             55.40             0.31

1 Dozen eggs/20 birds/week

2 Feed/dozen eggs

3 Average weight/egg (g)

4 Average egg shell thickness (mm)

CONCLUSION:

When halofuginone hydrobromide was fed at 3, 9 and 15 ppm, average body weight was decreased when compared with the control group. Feed efficiency was decreased with the 9 and 15 ppm levels of halofuginone hydrobromide. Hematological factors and tissue morphology were not influenced with any treatment level of halofuginone hydrobromide. Leghorn chickens fed the 3 ppm level of halofuginone hydrobromide during the growing period had numerically greater egg production when compared with birds fed the control during the growing period. Egg quality characteristics were not influenced with 3 and 9 ppm of halofuginone hydrobromide. Egg production, feed efficiency, egg weight, and egg shell thickness were decreased only in birds fed 15 ppm hallofuginone hydrobromide during the growing period.

REPLACEMENT BROILER BREEDER CHICKENS

Although halofuginone hydrobromide is not intended for use in broiler breeder chickens in production, additional data were collected after the 112-day growing period to determine the effect of feeding halofuginone hydrobromide during the growing period on subsequent fertility and hatchability. Halofuginone hydrobromide was withdrawn from all diets at 112 days.

Through mutual agreement between the sponsor and Food and Drug Administration, replacement broiler breeders fed the 15 ppm level of halofuginone hydrobromide were destroyed after 84 days on experiment due to high mortality, poor weight gain and poor feed consumption.

The results of this study for replacement broiler breeder chickens are presented in Table 12 and 13.

(Eds. note: The following table consists of 6 columns.)

TABLE 12: TOXICITY OF HALOFUGINONE HYDROBROMIDE IN REPLACEMENT BROILER BREEDER CHICKENS WHEN FED AT 0, 3 AND 9 PPM FROM ONE DAY OF AGE THROUGH 112 DAYS OF AGE 

Number of      Treatment            %         Body Weight       Feed
 Birds      ppm       (g/t)     Mortality*        (g)        Efficiency 
  190          0                        4.74              2831            3.18
  190          3         (2.72)         8.42              2760            3.23
  190          9         (8.16)        10.53              2648            3.24

* Based on 190 birds per treatment

(Eds. note: The following table consists of 7 columns.)

TABLE 13: TOXICITY OF HALOFUGINONE HYDROBROMIDE ON FERTILITY AND HATCHABILITY IN REPLACEMENT BROILER BREEDER CHICKENS WHEN FED AT 0, 3 AND 9 PPM 1

                               Percent Fertile         Percent Hatched  
 Number        Treatment
of Birds    ppm        g/t    Hatch 1    Hatch 2      Hatch 1    Hatch 2 
    
 190           0                    89.03       94.00          80.00        84.50 
 190           3         (2.72)     92.45       94.77          78.62        86.05
 190           9         (8.16)     89.86       93.63          81.08        84.71

1 Eggs were collected for 10 days during each of two 28-day periods: Hatch 1 and Hatch 2

CONCLUSIONS:

When halofuginone hydrobromide was fed at 9 ppm during the growing period, average body weight was numerically decreased when compared with the control group, but feed efficiency was not affected with the 3 and 9 ppm levels of halofuginone hydrobromide. Hematological factors, tissue morphology, fertility and hatchability were not influenced with 3 and 9 ppm of halofuginone hydrobromide fed during the growing period.

VI. HUMAN FOOD SAFETY

The original NADA contains an FOI Summary and complete information that demonstrate that food from animals fed halofuginone hydrobromide is safe for human consumption (NADA 130-951 - 50 FR 33718 - August 21, 1985).

VII. AGENCY CONCLUSIONS

The data submitted in support of this supplemental NADA satisfy the requirements of Section 512 of the Act and demonstrate that halofuginone hydrobromide when used under its proposed conditions of use is safe and effective for its labeled indications. The supplemental approval provides for the use of halofuginone hydrobromide (STENOROL®) at 2.72 g/t (3 ppm) in replacement cage laying chickens and replacement broiler breeder chickens to prevent coccidiosis caused by E. tenella, E. necatrix, E. acervulina, E. maxima, E. brunetti, and E mivati / E. mitis.

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. Accordingly, this approval did not require a reevaluation of safety and effectiveness data in the parent application.

Under section 512(c)(2)(F)(iii) of the Federal Food, Drug and Cosmetic Act, this approval qualifies for THREE (3) years of marketing exclusivity beginning on the date of approval because the supplemental application contains reports of new clinical or field investigations (other than bioequivalence or residues studies) essential to the approval of the application and conducted or sponsored by the applicant. The THREE years of marketing exclusivity applies only to the current supplemental approval.

Proper use by non-veterinarians can be expected because poultry producers routinely use medicated feed containing an animal drug for the prevention of coccidiosis in broiler chickens and turkeys. Directions are clearly written and there is reasonable certainly that the conditions of use, including mixing directions on the label, can and will be followed by the producer. The agency has concluded that this product can be approved for over-the-counter use.

VIII. LABELING

  1. Front Panel: STENOROL® (halofuginone hydrobromide), Type A medicated article
  2. Back Panel: STENOROL® (halofuginone hydrobromide), premix medicated coccidiostat, Dosage, Mixing Rate, Mixing Directions, Feeding Directions, Withdrawal Period, Caution, Human Exposure, Environmental Hazzard.
  3. Blue Bird: Type C medicated feed, replacement broiler breeder and replacement cage layer feed

Copies of these labels may be obtained by writing to the:

Food and Drug Administration
Freedom of Information Staff (HFI-35)
5600 Fishers Lane
Rockville, MD 20857

Or requests may be sent via fax to: (301) 443-1726. If there are problems sending a fax, call (301) 443-2414.