Nuflor Gold

Name: Nuflor Gold

Nuflor Gold 300 mg
Nuflor Gold injection
Nuflor Gold 40 mg
Nuflor Gold drug

NuflorGold™ (florfenicol)

Injectable Solution, An Antimicrobial
300 mg/mL

For subcutaneous use in beef and non-lactating dairy cattle only

Not for use in female dairy cattle 20 months of age or older or in calves to be processed for veal

PRODUCT
INFORMATION

Adverse Reactions

Transient inappetence, diarrhea, decreased water consumption, and injection site swelling have been associated with the use of florfenicol in cattle. In addition, anaphylaxis and collapse have been reported post-approval with the use of another formulation of florfenicol in cattle.

Nuflor Gold - Clinical Pharmacology

The pharmacokinetic disposition of Nuflor Gold™ was evaluated in feeder calves following a single subcutaneous injection at a dose rate of 40 mg florfenicol/kg body weight. Administration of Nuflor Gold™ resulted in florfenicol plasma concentrations of 2 µg (mcg)/mL within two hours of injection.

Table 1. Pharmacokinetic Parameter Values for Florfenicol Following a Single Subcutaneous Injection of Nuflor Gold™ at a Dose Rate of 40 mg Florfenicol/kg Body Weight to Feeder Calves (n=24).

	Cmax (µg/mL)	Tmax (hr)	AUClast (µg*hr/mL)	T½ (hr)
Cmax: Maximum observed plasma concentration Tmax: Time at which Cmax was observed AUClast: Area under the plasma-concentration-time curve from time zero to the last quantifiable concentration that is equal to or greater than the limit of quantification of the validated analytical method T½: Terminal elimination half-life % CV: Percent coefficient of variance
* T½ value could not be accurately estimated for one calf † Tmax is presented as the median value or range of observed values (minimum to maximum)
n	24	24	24	23*
Mean	5.93	5†	150	37.7
% CV	38.3	2-12†	20.9	27.3

Figure 1. Mean Florfenicol Plasma Concentration versus Time Following a Single Subcutaneous Injection of Nuflor Gold™ at a Dose Rate of 40 mg Florfenico/kg Body Weight in Feeder Calves (Mean ± Standard Error of the Mean)

MICROBIOLOGY

Florfenicol is a synthetic, broad-spectrum antibiotic active against many Gram-negative and Gram-positive bacteria isolated from domestic animals. It acts by binding to the 50S ribosomal subunit and inhibiting bacterial protein synthesis. Florfenicol is generally considered a bacteriostatic drug, but it exhibits bactericidal activity against certain bacterial species. In vitro studies demonstrate that florfenicol is active against the BRD pathogens M. haemolytica, P. multocida, H. somni, and M. bovis and that florfenicol exhibits bactericidal activity against strains of M. haemolytica and H. somni.

The minimum inhibitory concentrations (MICs) of florfenicol were determined for BRD isolates obtained from calves enrolled in BRD field studies in the U.S. in 2006 using methods recommended by the Clinical and Laboratory Standards Institute (M31-A2). Isolates were obtained from pre-treatment nasal swabs from all calves enrolled at all four sites, post-treatment nasal swabs from treatment failures in the Nuflor Gold Injectable Solution and saline control treatment groups at three sites, and lung tissue from one calf that died in the saline control treatment group. The results are shown below in Table 2.

Table 2. Florfenicol MIC values* of indicated pathogens isolated from cattle with naturally-occurring BRD

Indicated pathogens	Year of isolation	No. of isolates	MIC50† (µg/mL)	MIC90† (µg/mL)	MIC range (µg/mL)
* The correlation between in vitro susceptibility data and clinical effectiveness is unknown. † The lowest MIC to encompass 50% and 90% of the most susceptible isolates, respectively.
Mannheimia haemolytica	2006	158	1.0	1.0	0.5 to 32
Pasteurella multocida	2006	103	0.5	0.5	≤ 0.125 to 16
Histophilus somni	2006	85	≤ 0.125	≤ 0.125	≤ 0.125 to 0.25

Storage information

Store between 2°-30°C (36°-86°F). Use within 28 days of first use. Refrigeration is not required. The solution is light yellow to straw colored. Color does not affect potency.

How is Nuflor Gold Supplied

Nuflor Gold™ is packaged in 100 mL (NDC 0061-5327-01), 250 mL (NDC 0061-5327-02), and 500 mL (NDC 0061-5327-03) glass sterile multiple-dose vials.

Made in Germany

F-31331005
NADA 141-265, Approved by FDA.

PRINCIPAL DISPLAY PANEL - 250 mL vial label

NuflorGOLD™
(florfenicol)

Injectable Solution, An Antimicrobial
For subcutaneous use in beef and non-lactating dairy
cattle only
Not for use in female dairy cattle 20 months of age or
older or in calves to be processed for veal
Caution: Federal law restricts this drug to use by
or on the order of a licensed veterinarian
NADA 141-265, Approved by FDA

Intervet
Schering-Plough Animal Health

NDC 0061-5327-02

250 mL Multiple Dose Vial • 300 mg/mL • Sterile