Cefotan

CEFOTAN — cefotetan disodium injection, powder, for solution
CEFOTAN — cefotetan disodium injection, powder, for solution
Teligent Pharma, Inc.

1 gram carton PDP2 gram carton PDP

Rx only

For Intravenous or Intramuscular Use

To reduce the development of drug-resistant bacteria and maintain the effectiveness of CEFOTAN^® and other antibacterial drugs, CEFOTAN^® should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.

DESCRIPTION

CEFOTAN^® (cefotetan for Injection, USP), as cefotetan disodium, is a sterile, semisynthetic, broad-spectrum, beta-lactamase resistant, cephalosporin (cephamycin) antibacterial for parenteral administration. It is the disodium salt of [6R -(6α,7α)]-7-[[[4-(2-amino-1-carboxy-2-oxoethylidene)-1,3-dithietan-2-yl]carbonyl]amino]-7-methoxy-3-[[(1-methyl-1H -tetrazol-5-yl)thio]methyl]-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid. Structural formula:

CEFOTAN^® (cefotetan for Injection, USP) is supplied in vials containing 80 mg (3.5 mEq) of sodium per gram of cefotetan activity. It is a white to pale yellow powder which is very soluble in water. Reconstituted solutions of CEFOTAN^® (cefotetan for Injection, USP) are intended for intravenous and intramuscular administration. The solution varies from colorless to yellow depending on the concentration. The pH of freshly reconstituted solutions is usually between 4.5 to 6.5.

CEFOTAN^® (cefotetan for Injection, USP) is available in two vial strengths. Each 1 gram vial contains cefotetan disodium equivalent to 1 gram cefotetan activity. Each 2 gram vial contains cefotetan disodium equivalent to 2 grams cefotetan activity.

CLINICAL PHARMACOLOGY

High plasma levels of cefotetan are attained after intravenous and intramuscular administration of single doses to normal volunteers.

PLASMA CONCENTRATIONS AFTER 1 GRAM INTRAVENOUSa OR INTRAMUSCULAR DOSE Mean Plasma Concentration (mcg/mL)
Time After Injection
Route	15 min	30 min	1 h	2 h	4 h	8 h	12 h
IV	92	158	103	72	42	18	9
IM	34	56	71	68	47	20	9
a 30-minute infusion
PLASMA CONCENTRATIONS AFTER 2 GRAM INTRAVENOUSa OR INTRAMUSCULAR DOSE Mean Plasma Concentration (mcg/mL)
Time After Injection
Route	5 min	10 min	1 h	3 h	5 h	9 h	12 h
IV	237	223	135	74	48	22	12b
IM	—	20	75	91	69	33	19
a Injected over 3 minutes
b Concentrations estimated from regression line

Repeated administration of CEFOTAN^® does not result in accumulation of the drug in normal subjects.

Distribution

Cefotetan is 88% plasma protein bound.

Therapeutic concentrations of cefotetan are achieved in many body tissues and fluids including:

skin	ureter
muscle	bladder
fat	maxillary sinus mucosa
myometrium	tonsil
endometrium	bile
cervix	peritoneal fluid
ovary	umbilical cord serum
kidney	amniotic fluid

Metabolism and Excretion
The plasma elimination half-life of cefotetan is 3 to 4.6 hours after either intravenous or intramuscular administration.
No active metabolites of cefotetan have been detected; however, small amounts (less than 7%) of cefotetan in plasma and urine may be converted to its tautomer, which has antimicrobial activity similar to the parent drug.
In normal patients, from 51% to 81% of an administered dose of CEFOTAN^® is excreted unchanged by the kidneys over a 24-hour period, which results in high and prolonged urinary concentrations. Following intravenous doses of 1 gram and 2 grams, urinary concentrations are highest during the first hour and reach concentrations of approximately 1700 and 3500 mcg/mL, respectively.

Specific Populations

Patients with Renal Impairment
In volunteers with reduced renal function, the plasma half-life of cefotetan is prolonged. The mean terminal half-life increases with declining renal function, from approximately 4 hours in volunteers with normal renal function to about 10 hours in those with moderate renal impairment. There is a linear correlation between the systemic clearance of cefotetan and creatinine clearance. When renal function is impaired, a reduced dosing schedule based on creatinine clearance must be used (see DOSAGE AND ADMINISTRATION).

Geriatric patients

In pharmacokinetic studies of eight elderly patients (greater than 65 years) with normal renal function and six healthy volunteers (aged 25 to 28 years), mean±SD) Total Body Clearance (1.8±0.1 vs. 1.8±0.3 L/h) and mean±SD Volume of Distribution (10.4±1.2 vs. 10.3±1.6 L) were similar following administration of a one gram intravenous bolus dose.