SPECTRACEF Film-coated tablet Ref.[10834] Active ingredients: Cefditoren

BEFORE THERAPY WITH SPECTRACEF (CEFDITOREN PIVOXIL) IS INSTITUTED, CAREFUL INQUIRY SHOULD BE MADE TO DETERMINE WHETHER THE PATIENT HAS HAD PREVIOUS HYPERSENSITIVITY REACTIONS TO CEFDITOREN PIVOXIL, OTHER CEPHALOSPORINS, PENICILLINS, OR OTHER DRUGS. IF CEFDITOREN PIVOXIL IS TO BE GIVEN TO PENICILLIN-SENSITIVE PATIENTS, CAUTION SHOULD BE EXERCISED BECAUSE CROSS-HYPERSENSITIVITY AMONG β-LACTAM ANTIBIOTICS HAS BEEN CLEARLY DOCUMENTED AND MAY OCCUR IN UP TO 10% OF PATIENTS WITH A HISTORY OF PENICILLIN ALLERGY. IF AN ALLERGIC REACTION TO CEFDITOREN PIVOXIL OCCURS, THE DRUG SHOULD BE DISCONTINUED. SERIOUS ACUTE HYPERSENSITIVITY REACTIONS MAY REQUIRE TREATMENT WITH EPINEPHRINE AND OTHER EMERGENCY MEASURES, INCLUDING OXYGEN, INTRAVENOUS FLUIDS, INTRAVENOUS ANTIHISTAMINES, CORTICOSTEROIDS, PRESSOR AMINES, AND AIRWAY MANAGEMENT, AS CLINICALLY INDICATED.

Pseudomembranous colitis has been reported with nearly all antibacterial agents, including cefditoren pivoxil, and may range in severity from mild to life-threatening. Therefore, it is important to consider this diagnosis in patients who present with diarrhea subsequent to the administration of antibacterial agents.

Treatment with antibacterial agents alters normal flora of the colon and may permit overgrowth of clostridia. Studies indicate that a toxin produced by Clostridium difficile (C. difficile) is a primary cause of antibiotic-associated colitis.

After the diagnosis of pseudomembranous colitis has been established, appropriate therapeutic measures should be initiated. Mild cases of pseudomembranous colitis usually respond to drug discontinuation alone. In moderate to severe cases, consideration should be given to management with fluids and electrolytes, protein supplementation, and treatment with an antibacterial drug clinically effective against C. difficile colitis.

Clinical Trials – SPECTRACEF (cefditoren pivoxil) Tablets (Adults and Adolescent Patients ≥12 Years of Age)

In clinical trials, 4834 adult and adolescent patients have been treated with the recommended doses of cefditoren pivoxil tablets (200 mg or 400 mg BID). Most adverse events were mild and self-limiting. No deaths or permanent disabilities have been attributed to cefditoren.

The following adverse events were thought by the investigators to be possibly, probably, or definitely related to cefditoren tablets in multiple-dose clinical trials:

Treatment-Related Adverse Events in Trials in Adults and Adolescent Patients ≥ 12 Years of age):

^a includes amoxicillin/clavulanate, cefadroxil monohydrate, cefuroxime axetil, cefpodoxime proxetil, clarithromycin, and penicillin
^b 1428 females
^c 1135 females
^d 1461 females

The overall incidence of adverse events, and in particular diarrhea, increased with the higher recommended dose of SPECTRACEF.

Treatment related adverse events experienced by <1% but >0.1% of patients who received 200 mg or 400 mg BID of cefditoren pivoxil were abnormal dreams, allergic reaction, anorexia, asthenia, asthma, coagulation time increased, constipation, dizziness, dry mouth, eructation, face edema, fever, flatulence, fungal infection, gastrointestinal disorder, hyperglycemia, increased appetite, insomnia, leukopenia, leukorrhea, liver function test abnormal, myalgia, nervousness, oral moniliasis, pain, peripheral edema, pharyngitis, pseudomembranous colitis, pruritus, rash, rhinitis, sinusitis, somnolence, stomatitis, sweating, taste perversion, thirst, thrombocythemia, urticaria, and vaginitis. Pseudomembranous colitis symptoms may begin during or after antibiotic treatment. (See WARNINGS.)

Sixty-one of 2675 (2%) patients who received 200 mg BID and 69 of 2159 (3%) patients who received 400 mg BID of cefditoren pivoxil discontinued medication due to adverse events thought by the investigators to be possibly, probably, or definitely associated with cefditoren therapy. The discontinuations were primarily for gastrointestinal disturbances, usually diarrhea or nausea. Diarrhea was the reason for discontinuation in 19 of 2675 (0.7%) patients who received 200 mg BID and in 31 of 2159 (1.4%) patients who received 400 mg BID of cefditoren pivoxil.

Changes in laboratory parameters of possible clinical significance, without regard to drug relationship and which occurred in ≥1% of patients who received cefditoren pivoxil 200 mg or 400 mg BID, were hematuria (3.0% and 3.1%), increased urine white blood cells (2.3% and 2.3%), decreased hematocrit (2.1% and 2.2%), and increased glucose (1.8% and 1.1%). Those events which occurred in <1% but >0.1% of patients included the following: increased/decreased white blood cells, increased eosinophils, decreased neutrophils, increased lymphocytes, increased platelet count, decreased hemoglobin, decreased sodium, increased potassium, decreased chloride, decreased inorganic phosphorus, decreased calcium, increased SGPT/ALT, increased SGOT/AST, increased cholesterol, decreased albumin, proteinuria, and increased BUN. It is not known if these abnormalities were caused by the drug or the underlying condition being treated.

Cephalosporin Class Adverse Reactions

In addition to the adverse reactions listed above which have been observed in patients treated with cefditoren pivoxil, the following adverse reactions and altered laboratory test results have been reported for cephalosporin class antibiotics:

Adverse Reactions: Allergic reactions, anaphylaxis, drug fever, Stevens-Johnson syndrome, serum sickness-like reaction, erythema multiforme, toxic epidermal necrolysis, colitis, renal dysfunction, toxic nephropathy, reversible hyperactivity, hypertonia, hepatic dysfunction including cholestasis, aplastic anemia, hemolytic anemia, hemorrhage, and superinfection.

Altered Laboratory Tests: Prolonged prothrombin time, positive direct Coombs' test, false-positive test for urinary glucose, elevated alkaline phosphatase, elevated bilirubin, levated LDH, increased creatinine, pancytopenia, neutropenia, and agranulocytosis.

Several cephalosporins have been implicated in triggering seizures, particularly in patients with renal impairment when the dosage was not reduced. (See DOSAGE AND ADMINISTRATION.) If seizures associated with drug therapy occur, the drug should be discontinued. Anticonvulsant therapy can be given if clinically indicated.

Postmarketing Experience

The following adverse experiences, regardless of their relationship to cefditoren pivoxil, have been reported during extensive postmarketing experience, beginning with approval in Japan in 1994: pneumonia interstitial, eosinophilic pneumonia acute, acute renal failure, arthralgia, thrombocytopenia, erythema multiforme, Stevens-Johnson Syndrome, toxic epidermal necrolysis.

Prescribing SPECTRACEF in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

SPECTRACEF is not recommended when prolonged antibiotic treatment is necessary, since other pivalate-containing compounds have caused clinical manifestations of carnitine deficiency when used over a period of months. No clinical effects of carnitine decrease have been associated with short-term treatment. The effects on carnitine concentrations of repeat short-term courses of SPECTRACEF are not known.

In community-acquired pneumonia patients (N=192, mean age 50.3 ± 17.2 years) given a 200 mg BID regimen for 14 days, the mean decrease in serum concentrations of total carnitine while on therapy was 13.8 ± 10.8 nmole/mL, representing a 30% decrease in serum carnitine concentrations. In community-acquired pneumonia patients (N=192, mean age 51.3 ± 17.8 years) given a 400 mg BID regimen for 14 days, the mean decrease in serum concentrations of total carnitine while on therapy was 21.5 ± 13.1 mole/mL, representing a 46% decrease in serum carnitine concentrations. Plasma concentrations of carnitine returned to the normal control range within 7 days after discontinuation of cefditoren pivoxil. Comparable decreases in carnitine were observed in healthy volunteers (mean age 33.6 ± 7.4 years) following a 200 mg or 400 mg BID regimen. (See CLINICAL PHARMACOLOGY.) Community-acquired pneumonia clinical trials demonstrated no adverse events attributable to decreases in serum carnitine concentrations.

However, some sub-populations (e.g., patients with renal impairment, patients with decreased muscle mass) may be at increased risk for reductions in serum carnitine concentrations during cefditoren pivoxil therapy. Furthermore, the appropriate dose in patients with end-stage renal disease has not been determined. (See DOSAGE AND ADMINISTRATION, Patients with Renal Insufficiency).

As with other antibiotics, prolonged treatment may result in the possible emergence and overgrowth of resistant organisms. Careful observation of the patient is essential. If superinfection occurs during therapy, appropriate alternative therapy should be administered.

Cephalosporins may be associated with a fall in prothrombin activity. Those at risk include patients with renal or hepatic impairment, or poor nutritional state, as well as patients receiving a protracted course of antimicrobial therapy, and patients previously stabilized on anticoagulant therapy. Prothrombin time should be monitored in patients at risk and exogenous vitamin K administered as indicated. In clinical trials, there was no difference between cefditoren and comparator cephalosporins in the incidence of increased prothrombin time.

Patients should be counseled that antibacterial drugs including SPECTRACEF should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When SPECTRACEF is prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by SPECTRACEF or other antibacterial drugs in the future.

SPECTRACEF (cefditoren pivoxil) should be taken with meals to enhance absorption.

SPECTRACEF may be taken concomitantly with oral contraceptives.

It is not recommended that SPECTRACEF be taken concomitantly with antacids or other drugs taken to reduce stomach acids. (See PRECAUTIONS, Drug Interactions.)

SPECTRACEF tablets contain sodium caseinate, a milk protein. Patients with milk protein hypersensitivity (not lactose intolerance) should not be administered SPECTRACEF.

Oral Contraceptives

Multiple doses of cefditoren pivoxil had no effect on the pharmacokinetics of ethinyl estradiol, the estrogenic component in most oral contraceptives.

Antacids

Co-administration of a single dose of an antacid which contained both magnesium (800 mg) and aluminum (900 mg) hydroxides reduced the oral absorption of a single 400 mg dose of cefditoren pivoxil administered following a meal, as evidenced by a 14% decrease in mean C_max and an 11% decrease in mean AUC. Although the clinical significance is not known, it is not recommended that cefditoren pivoxil be taken concomitantly with antacids.

H₂-Receptor Antagonists

Co-administration of a single dose of intravenously administered famotidine (20 mg) reduced the oral absorption of a single 400 mg dose of cefditoren pivoxil administered following a meal, as evidenced by a 27% decrease in mean C_max and a 22% decrease in mean AUC. Although the clinical significance is not known, it is not recommended that cefditoren pivoxil be taken concomitantly with H₂ receptor antagonists.

Probenecid

As with other β-lactam antibiotics, co-administration of probenecid with cefditoren pivoxil resulted in an increase in the plasma exposure of cefditoren, with a 49% increase in mean C_max, a 122% increase in mean AUC, and a 53% increase in t_1/2.

Pregnancy Category B.

Cefditoren pivoxil was not teratogenic up to the highest doses tested in rats and rabbits. In rats, this dose was 1000 mg/kg/day, which is approximately 24 times a human dose of 200 mg BID based on mg/m²/day. In rabbits, the highest dose tested was 90 mg/kg/day, which is approximately four times a human dose of 200 mg BID based on mg/m²/day. This dose produced severe maternal toxicity and resulted in fetal toxicity and abortions.

In a postnatal development study in rats, cefditoren pivoxil produced no adverse effects on postnatal survival, physical and behavioral development, learning abilities, and reproductive capability at sexual maturity when tested at doses of up to 750 mg/kg/day, the highest dose tested. This is approximately 18 times a human dose of 200 mg BID based on mg/m²/day.

There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproductive studies are not always predictive of human response, this drug should be used during pregnancy only if clearly needed.

Cefditoren pivoxil has not been studied for use during labor and delivery.

Cefditoren was detected in the breast milk of lactating rats. Because many drugs are excreted in human breast milk, caution should be exercised when cefditoren pivoxil is administered to nursing women.

Use of cefditoren pivoxil is not recommended for pediatric patients less than 12 years of age. The safety and efficacy of cefditoren pivoxil tablets in this population, including any effects of altered carnitine concentration, have not been established. (See PRECAUTIONS, General.)

Of the 2675 patients in clinical studies who received cefditoren pivoxil 200 mg BID, 308 (12%) were >65 years of age. Of the 2159 patients in clinical studies who received cefditoren pivoxil 400 mg BID, 307 (14%) were >65 years of age. No clinically significant differences in effectiveness or safety were observed between older and younger patients. No dose adjustments are necessary in geriatric patients with normal (for their age) renal function. This drug is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function. (See DOSAGE AND ADMINISTRATION.)

Cephalosporins are known to occasionally induce a positive direct Coombs' test. A false-positive reaction for glucose in the urine may occur with copper reduction tests (Benedict’s or Fehling’s solution or with CLINITEST tablets), but not with enzyme-based tests for glycosuria (e.g., CLINISTIX, TES-TAPE). As a false-negative result may occur in the ferricyanide test, it is recommended that either the glucose oxidase or hexokinase method be used to determine blood/plasma glucose levels in patients receiving cefditoren pivoxil.