Sunday 15 April 2012

Levofloxacin 500 mg Film-coated Tablets





1. Name Of The Medicinal Product



Levofloxacin 500 mg Film-coated Tablets


2. Qualitative And Quantitative Composition



Each film coated tablet contains 500 mg of levofloxacin as active substance corresponding to 512.46 mg of levofloxacin hemihydrate.



For a full list of excipients, see section 6.1



3. Pharmaceutical Form



Film-coated tablet



For 500 mg tablets: Pink coloured, capsule shaped, biconvex, film coated tablet with break line on both sides. Debossed 'L' and 'V' either side of the break line on one face.



The tablets can be divided into equal halves.



4. Clinical Particulars



4.1 Therapeutic Indications



In adults with infections of mild or moderate severity, Levofloxacin Tablets are indicated for the treatment of the following infections when due to levofloxacin-susceptible microorganisms: (see section 5.1)



• Acute sinusitis (adequately diagnosed according to national and/or local guidelines on the treatment of respiratory tract infections, and when it is considered inappropriate to use antibacterial agents that are commonly recommended for the initial treatment of this infection or when these have failed to resolve the infection),



• Acute exacerbations of chronic bronchitis (adequately diagnosed according to national and/or local guidelines on the treatment of respiratory tract infections, and when it is considered inappropriate to use antibacterial agents that are commonly recommended for the initial treatment of this infection or when these have failed to resolve the infection),



• Community-acquired pneumonia (when it is considered inappropriate to use antibacterial agents that are commonly recommended for the initial treatment of this infection),



• For 250mg only: Uncomplicated urinary tract infections



• Complicated urinary tract infections (including pyelonephritis)



• Chronic bacterial prostatitis.



• Skin and soft tissue infections.



Consideration should be given to official guidance on the appropriate use of antibacterial agents.



4.2 Posology And Method Of Administration



Levofloxacin Tablets are administered once or twice daily. The dosage depends on the type and severity of the infection and the sensitivity of the presumed causative pathogen.



Treatment time



The duration of therapy varies according to the course of the disease (see table below). As with antibiotic therapy in general, administration of Levofloxacin Tablets should be continued for a minimum of 48 to 72 hours after the patient has become afebrile or evidence of bacterial eradication has been obtained.



Method of administration



Levofloxacin Tablets should be swallowed whole and with sufficient amount of liquid. The tablets may be taken during meals or between meals. Levofloxacin Tablets should be taken at least two hours before iron salts, antacids and sucralfate administration since reduction of absorption can occur (see section 4.5).



The following dose recommendations can be given for Levofloxacin Tablets:



Dosage in patients with normal renal function



(creatinine clearance > 50 ml/min)




























Indication




Daily dose regimen (according to severity)




Duration of treatment




Acute sinusitis




500 mg once daily




10 - 14 days




Acute exacerbations of chronic bronchitis




250 to 500 mg once daily




7 - 10 days




Community-acquired pneumonia




500 mg once or twice daily




7 - 14 days




Uncomplicated urinary tract infections




250 mg once daily




3 days




Complicated urinary tract infections including pyelonephritis




250 mg once daily1




7 - 10 days




Chronic bacterial prostatitis




500 mg once daily




28 days




Skin and soft tissue infections




250 mg once daily or 500 mg once or twice daily2




7 - 14 days



1,2 Consideration should be given to increasing the dose in cases of severe infection and special attention should be paid to available information on resistance to levofloxacin before commencing therapy.



1 Because of the increasing E.coli resistance the dose 500 mg/day should be considered.



2 Because of the increasing Staphylococcus resistance the dose 500 mg twice daily should be considered.



Special Populations



Impaired renal function (creatinine clearance




























Creatinine clearance




Dosage regimen


  


250 mg/24 h




500 mg/24 h




500 mg/12 h


 


First dose: 250 mg




First dose: 500 mg




First dose: 500 mg


 


50-20 ml/min




Then:125 mg/24h




Then: 250 mg/24 h




Then:250 mg/12 h




19-10 ml/min




Then: 125 mg/48 h




Then: 125 mg/24 h




Then:125 mg/12 h




< 10 ml/min (including haemodialysis and CAPD)1




Then: 125 mg/48 h




Then: 125 mg/24 h




Then:125 mg/24 h



1 No additional doses are required after haemodialysis or continuous ambulatory peritoneal dialysis (CAPD).



Impaired liver function



No adjustment of dosage is required since levofloxacin is not metabolised to any relevant extent by the liver and is mainly excreted by the kidneys.



Dosage in elderly



No adjustment of dosage is required in the elderly, other than that imposed by consideration of renal function (see section 4.4 QT interval prolongation).



In children



Levofloxacin is contraindicated in children and growing adolescents (less than 18 years of age) (see section 4.3).



4.3 Contraindications



Levofloxacin Tablets must not be used:



• in patients hypersensitive to levofloxacin or other quinolones or any of the excipients,



• in patients with epilepsy,



• in patients with history of tendon disorders related to fluoroquinolone administration,



• in children or growing adolescents (up to age of 18)



• during pregnancy,



• in breast-feeding women.



4.4 Special Warnings And Precautions For Use



In the most severe cases of pneumococcal pneumonia Levofloxacin Tablets may not be the optimal therapy.



Nosocomial infections due to P. aeruginosa may require combination therapy.



Methicillin-resistant Staphylococcus aureus (MRSA)



Levofloxacin is not effective against infections caused by MRSA (see section 5.1). In infections suspicious for MRSA levofloxacin should be combined with an agent approved to treat MRSA infections.



Tendinitis and tendon rupture



Tendinitis may rarely occur. It most frequently involves the Achilles tendon and may lead to tendon rupture. The risk of tendinitis and tendon rupture is increased in the elderly and in patients using corticosteroids. Close monitoring of these patients is therefore necessary if they are prescribed Levofloxacin Tablets. All patients should consult their physician if they experience symptoms of tendinitis. If tendinitis is suspected, treatment with Levofloxacin Tablets must be halted immediately, and appropriate treatment (e.g. immobilisation) must be initiated for the affected tendon.



Clostridium difficile-associated disease



Diarrhoea, particularly if severe, persistent and/or bloody, during or after treatment with Levofloxacin Tablets, may be symptomatic of Clostridium difficile-associated disease, the most severe form of which is pseudomembranous enterocolitis. If pseudomembranous enterocolitis is suspected, Levofloxacin Tablets must be stopped immediately and patients should be treated with supportive measures and specific therapy without delay (e.g. oral metronidazole or vancomycin). Products inhibiting the peristalsis are contraindicated in this clinical situation.



Patients predisposed to seizures



Levofloxacin Tablets are contraindicated in patients with a history of epilepsy and, as with other quinolones, should be used with extreme caution in patients predisposed to seizures, such as patients with pre-existing central nervous system damage; concomitant treatment with fenbufen and similar non-steroidal anti-inflammatory drugs or with drugs which lower the cerebral seizure threshold, such as theophylline (see section 4.5). In case of convulsive seizures, treatment with levofloxacin should be discontinued.



Patients with G-6- phosphate dehydrogenase deficiency



Patients with latent or actual defects in glucose-6-phosphate dehydrogenase activity may be prone to haemolytic reactions when treated with quinolone antibacterial agents, and so levofloxacin should be used with caution.



Patients with renal impairment



Since levofloxacin is excreted mainly by the kidneys, the dose of Levofloxacin Tablets should be adjusted in patients with renal impairment. (see section 4.2).



Hypersensitivity reactions



Levofloxacin can cause serious, potentially fatal hypersensitivity reactions (e.g. angioedema to anaphylactic shock), occasionally following the initial dose (see section 4.8). Patients should discontinue treatment immediately and contact their physician or an emergency physician, who will initiate appropriate emergency measures.



Hypoglycemia



As with all quinolones, hypoglycemia has been reported, usually in diabetic patients receiving concomitant treatment with an oral hypoglycemic agent (e.g., glibenclamide) or with insulin. In these diabetic patients, careful monitoring of blood glucose is recommended. (see section 4.8).



Prevention of photosensitisation



Although photosensitisation is very rare with levofloxacin, it is recommended that patients should not expose themselves unnecessarily to strong sunlight or to artificial UV rays (e.g. sunray lamp, solarium), in order to prevent photosensitisation.



Patients treated with Vitamin K antagonists



Due to possible increase in coagulation tests (PT/INR) and/or bleeding in patients treated with levofloxacin in combination with a vitamin K antagonist (e.g. warfarin), coagulation tests should be monitored when these drugs are given concomitantly (see section 4.5).



Psychotic reactions



Psychotic reactions have been reported in patients receiving quinolones, including levofloxacin. In very rare cases these have progressed to suicidal thoughts and self-endangering behaviour- sometimes after only a single dose of levofloxacin (see section 4.8). In the event that the patient develops these reactions, levofloxacin should be discontinued and appropriate measures instituted. Caution is recommended if levofloxacin is to be used in psychotic patients or in patients with a history of psychiatric disease.



Cardiac disorders



Caution should be taken when using fluoroquinolones, including levofloxacin, in patients with known risk factors for prolongation of the QT interval such as, for example:



- congenital long QT syndrome



-concomitant use of drugs that are known to prolong the QT interval (e.g. Class IA and III antiarrhythmics, tricyclic antidepressants, macrolides).



- uncorrected electrolyte imbalance (e.g. hypokalemia, hypomagnesemia)



- elderly



- cardiac disease (e.g. heart failure, myocardial infarction, bradycardia)



(see section 4.2 Elderly, section 4.5, section 4.8, section 4.9).



Peripheral neuropathy



Sensory or sensorimotor peripheral neuropathy has been reported in patients receiving fluoroquinolones, including levofloxacin, which can be rapid in its onset. Levofloxacin should be discontinued if the patient experiences symptoms of neuropathy in order to prevent the development of an irreversible condition.



Opiates



In patients treated with levofloxacin, determination of opiates in urine may give false-positive results. It may be necessary to confirm positive opiate screens by a more specific method.



Hepatobiliary disorders



Cases of hepatic necrosis up to life threatening hepatic failure have been reported with levofloxacin, primarily in patients with severe underlying diseases, e.g. sepsis (see section 4.8). Patients should be advised to stop treatment and contact their doctor if signs and symptoms of hepatic disease develop such as anorexia, jaundice, dark urine, pruritus or tender abdomen.



4.5 Interaction With Other Medicinal Products And Other Forms Of Interaction



Effect of other medicinal products on levofloxacin



Iron salts, magnesium- or aluminium-containing antacids



Levofloxacin absorption is significantly reduced when iron salts, or magnesium- or aluminium-containing antacids are administered concomitantly. It is recommended that preparations containing divalent or trivalent cations such as iron salts, or magnesium- or aluminium-containing antacids should not be taken 2 hours before or after Levofloxacin Tablets administration (see section 4.2). No interaction was found with calcium carbonate.



Sucralfate



The bioavailability of Levofloxacin Tablets is significantly reduced when administered together with sucralfate. If the patient is to receive both sucralfate and Levofloxacin Tablets, it is best to administer sucralfate 2 hours after the Levofloxacin Tablets administration (see section 4.2).



Theophylline, fenbufen or similar non-steroidal anti-inflammatory drugs



No pharmacokinetic interactions of levofloxacin were found with theophylline in a clinical study. However a pronounced lowering of the cerebral seizure threshold may occur when quinolones are given concurrently with theophylline, non-steroidal anti-inflammatory drugs, or other agents which lower the seizure threshold.



Levofloxacin concentrations were about 13 % higher in the presence of fenbufen than when administered alone.



Probenecid and cimetidine



Probenecid and cimetidine had a statistically significant effect on the elimination of levofloxacin. The renal clearance of levofloxacin was reduced by cimetidine (24 %) and probenecid (34 %). This is because both drugs are capable of blocking the renal tubular secretion of levofloxacin. However, at the tested doses in the study, the statistically significant kinetic differences are unlikely to be of clinical relevance.



Caution should be exercised when levofloxacin is coadministered with drugs that effect the tubular renal secretion such as probenecid and cimetidine, especially in renally impaired patients.



Effect of levofloxacin on other medicinal products



Ciclosporin



The half-life of ciclosporin was increased by 33 % when coadministered with levofloxacin.



Vitamin K antagonists



Increased coagulation tests (PT/INR) and/or bleeding, which may be severe, have been reported in patients treated with levofloxacin in combination with a vitamin K antagonist (e.g. warfarin). Coagulation tests, therefore, should be monitored in patients treated with vitamin K antagonists (see section 4.4).



Drugs known to prolong the QT interval



Levofloxacin, like other fluoroquinolones, should be used with caution in patients receiving drugs known to prolong the QT interval (e.g. Class IA and III antiarrhythmics, tricyclic antidepressants, macrolides, antipsychotic). (See section 4.4 ).



Other forms of interactions



Meals



There is no clinically relevant interaction with food. Levofloxacin Tablets may therefore be administered regardless of food intake.



Other relevant information



Clinical pharmacology studies have shown that the pharmacokinetics of levofloxacin were not affected to any clinically relevant extent when levofloxacin was administered together with the following drugs:



- calcium carbonate



- digoxin



- glibenclamide



- ranitidine.



4.6 Pregnancy And Lactation



Pregnancy



There are no data with respect to the use of levofloxacin in pregnant women. Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity (see section 5.3). In juvenile and prenatal animals exposed to quinolones, effects on immature cartilage have been observed; thus, it cannot be excluded that the drug could cause damage to articular cartilage in the human immature organism / fetus (see section 5.3). The product is therefore contraindicated during pregnancy.



Lactation



There is insufficient information with respect to the excretion of levofloxacin in human and/or animal milk. In the absence of these data and given the potential risk of articular damage, levofloxacin is contraindicated during breast-feeding.



4.7 Effects On Ability To Drive And Use Machines



Some undesirable effects (e.g. dizziness/vertigo, drowsiness, visual disturbances) may impair the patient's ability to concentrate and react, and therefore may constitute a risk in situations where these abilities are of special importance (e.g. driving a car or operating machinery).



4.8 Undesirable Effects



The information given below is based on data from clinical studies in more than 5000 patients and on extensive post marketing experience.



The adverse reactions are described according to the MedDRA system organ class below.



Frequencies are defined using the following convention: very common (



Within each frequency grouping, undesirable effects are presented in order of decreasing seriousness.



Cardiac disorders



Rare: Tachycardia



Not Known: ventricular arrhythmia and torsades de pointes (reported predominantly in patients with risk factors for QT prolongation), Electrocardiogram QT prolonged (see section 4.4 and section 4.9)



Blood and lymphatic system disorders



Uncommon : Leukopenia, eosinophilia



Rare : Thrombocytopenia, neutropenia



Very rare : Agranulocytosis



Not Known : Pancytopenia, haemolytic anaemia



Nervous system disorders



Uncommon : Dizziness, headache, somnolence



Rare : Convulsion, tremor, paraesthesia,



Very rare: sensory or sensorimotor peripheral neuropathy, dysgeusia including ageusia, parosmia including anosmia



Eye disorders



Very rare: Visual disturbance



Ear and Labyrinth disorders



Uncommon: Vertigo



Very rare: Hearing impaired



Not known: Tinnitus



Respiratory, thoracic and mediastinal disorders



Rare: Bronchospasm, dyspnoea



Very rare: Pneumonitis allergic



Gastrointestinal disorders



Common: Diarrhoea, nausea



Uncommon: Vomiting, abdominal pain, dyspepsia, flatulence, constipation



Rare: Diarrhoea -haemorrhagic which in very rare cases may be indicative of enterocolitis, including pseudomembranous colitis



Renal and urinary disorders



Uncommon: Blood creatinine increased



Very rare: Renal failure acute (e.g. due to nephritis interstitial)



Skin and subcutaneous tissue disorders



Uncommon: Rash, pruritus



Rare: Urticaria



Very rare: Angioneurotic oedema, photosensitivity reaction



Not Known: Toxic epidermal necrolysis, Stevens-Johnson syndrome, erythema multiforme, hyperhidrosis



Mucocutaneous reactions may sometimes occur even after the first dose



Musculoskeletal and Connective tissue disorders



Rare: Tendon disorder (see section 4.4) including tendinitis (e.g. Achilles tendon), arthralgia, myalgia



Very rare: Tendon rupture (see section 4.4). This undesirable effect may occur within 48 hours of starting treatment and may be bilateral, muscular weakness which may be of special importance in patients with myasthenia gravis



Not Known: Rhabdomyolysis



Metabolism and nutrition disorders



Uncommon: Anorexia



Very rare: Hypoglycemia, particularly in diabetic patients (see section 4.4)



Infections and infestations



Uncommon: Fungal infection (and proliferation of other resistant microorganisms)



Vascular disorders



Rare: Hypotension



General disorders and administration site conditions



Uncommon: Asthenia



Very rare: Pyrexia



Not known: Pain (including pain in back, chest, and extremities)



Immune system disorders



Very rare: Anaphylactic shock (see section 4.4)



Anaphylactic and anaphylactoid reactions may sometimes occur even after the first dose



Not known: Hypersensitivity (see section 4.4)



Hepatobiliary disorders



Common: Hepatic enzyme increased (ALT/AST, alkaline phosphatase, GGT)



Uncommon: Blood bilirubin increased



Very rare: Hepatitis



Not known: Jaundice and severe liver injury, including cases with acute liver failure, have been reported with levofloxacin, primarily in patients with severe underlying diseases (see section 4.4).



Psychiatric disorders



Uncommon: Insomnia, nervousness



Rare: Psychotic disorder, Depression, confusional state, agitation, anxiety



Very rare: Psychotic reactions with self-endangering behaviour including suicidal ideation or acts (see section 4.4), hallucination



Other undesirable effects which have been associated with fluoroquinolone administration include:



• extrapyramidal symptoms and other disorders of muscular coordination,



• hypersensitivity vasculitis,



• attacks of porphyria in patients with porphyria.



4.9 Overdose



According to toxicity studies in animals or clinical pharmacology studies performed with supra-therapeutic doses, the most important signs to be expected following acute overdosage of levofloxacin are central nervous system symptoms such as confusion, dizziness, impairment of consciousness, and convulsive seizures, increases in QT interval as well as gastro-intestinal reactions such as nausea and mucosal erosions.



In the event of overdose, symptomatic treatment should be implemented. ECG monitoring should be undertaken, because of the possibility of QT interval prolongation. Antacids may be used for protection of gastric mucosa. Haemodialysis, including peritoneal dialysis and CAPD, are not effective in removing levofloxacin from the body. No specific antidote exists.



5. Pharmacological Properties



5.1 Pharmacodynamic Properties



Pharmacotherapeutic group: Antiifectives for systemic use - Antibacterials for systemic use - Quinolone antibasterials - Fluoroquinolones



ATC code: J01MA12



Levofloxacin is a synthetic antibacterial agent of the fluoroquinolone class and is the S (-) enantiomer of the racemic drug substance ofloxacin.



Mechanism of action



As a fluoroquinolone antibacterial agent, levofloxacin acts on the DNA-DNA-gyrase complex and topoisomerase IV.



PK/PD releationship



The degree of the bactericidal activity of levofloxacin depends on the ratio of the maximum concentration in serum (Cmax) or the area under the curve (AUC) and the minimal inhibitory concentration (MIC).



Mechanism(s) of resisance



The main mechanism of resistance is due to a gyr-A mutation. In vitro there is a cross-resistance between levofloxacin and other fluoroquinolones.



Due to the mechanism of action, there is generally no cross-resistance between levofloxacin and other classes of antibacterial agents.



Breakpoints



The EUCAST recommended MIC breakpoints for levofloxacin, separating susceptible from intermediately susceptible organisms and intermediately susceptible from resistant organisms are presented in the below table for MIC testing (mg/L).



EUCAST clinical MIC breakpoints for levofloxacin (2006-06-20):































Pathogen




Susceptible




Resistant




Enterobacteriacae







>2 mg/L




Pseudomonas spp.







>2 mg/L




Acinetobacter spp.







>2 mg/L




Staphylococcus spp.







>2 mg/L




S.pneumoniae1







>2 mg/L




Streptococcus A,B,C,G







>2 mg/L




H.influenzae M.catarrhalis 2







>1 mg/L




Non-species related breakpoints 3







>2 mg/L



1 the S/I-breakpoint was increased from 1.0 to 2.0 to avoid dividing the wild type MIC distribution. The breakpoints relate to high dose therapy.



2 Strains with MIC values above the S/I breakpoint are very rare or not yet reported. The identification and antimicrobial susceptibility tests on any such isolate must be repeated and if the result is confirmed the isolate sent to a reference laboratory.



3 Non-species related breakpoints have been determined mainly on the basis of pharmacokinetic/pharmacodynamic data and are independent of MIC distributions of specific species. They are for use only for species that have not been given a species-specific breakpoint and are not for use with species where susceptibility testing is not recommended or for which there is insufficient evidence that the species in question is a good target (Enterococcus, Neisseria, Gram negative anaerobes)



The prevalence of resistance may vary geographically and with time for selected species and local information on resistance is desirable, particularly when treating severe infections. As necessary, expert advice should be sought when the local prevalence of resistance is such that the utility of the agent in at least some types of infections is questionable.





























Commonly susceptible species




Aerobic Gram-positive bacteria




Staphylococcus aureus* methicillin-susceptible



Coagulase negative meticillin-susceptible



Staphylococcus, including staphylococcus saprophyticus



Streptococci




Aerobic Gram- negative bacteria




Eikenella corrodens



Haemophilus influenzae *



Haemophilus para-influenzae *



Klebsiella oxytoca



Klebsiella pneumoniae *



Legionella pneumophila*



Moraxella catarrhalis *



Pasteurella multocida



Proteus vulgaris



Providencia rettgeri




Anaerobic bacteria




Clostridium perfringens



Fusobacterium



Prevotella($),



Propionibacterium




Other




Chlamydophila pneumoniae *



Chlamydophila psittaci



Chlamydia trachomatis



Mycoplasma pneumoniae *



Mycoplasma hominis



Ureaplasma urealyticum




Species for which acquired resistance may be a problem




Aerobic Gram-positive bacteria




Enterococcus faecalis*



Staphylococcus aureus methicillin-resistant



Staphylococcus coagulase negative methicillin-resistant




Aerobic Gram- negative bacteria




Acinetobacter baumannii *



Citrobacter freundii *



Enterobacter aerogenes



Enterobacter agglomerans



Enterobacter cloacae *



Escherichia coli *



Morganella morganii *



Proteus mirabilis *



Providencia stuartii



Pseudomonas aeruginosa*



Serratia marcescens *




Anaerobic bacteria




Peptostreptococcus




Naturally resistant species




Aerobic Gram-positive bacteria




Enterococcus faecium




Aerobic Gram-negative bacteria




Burkholderia cepacia




Anaerobic bacteria




Bacteroides



Clostridium difficile




* Clinical efficacy has been demonstrated for susceptible isolates in the approved clinical indications.




$ natural intermediate susceptibility



Other information



Nosocomial infections due to P. aeruginosa may require combination therapy.



5.2 Pharmacokinetic Properties



Absorption



Orally administered levofloxacin is rapidly and almost completely absorbed with peak plasma concentrations being obtained within 1 h. The absolute bioavailability is approximately 100 %. Food has little effect on the absorption of levofloxacin.



Distribution



Approximately 30 - 40 % of levofloxacin is bound to serum protein. 500 mg once daily multiple dosing with levofloxacin showed negligible accumulation. There is modest but predictable accumulation of levofloxacin after doses of 500 mg twice daily. Steady-state is achieved within 3 days.



Penetration into tissues and body fluids:



Penetration into Bronchial Mucosa, Epithelial Lining Fluid (ELF)



Maximum levofloxacin concentrations in bronchial mucosa and epithelial lining fluid after 500 mg p.o. were 8.3 μg/g and 10.8 μg/ml respectively. These were reached approximately one hour after administration.



Penetration into Lung Tissue



Maximum levofloxacin concentrations in lung tissue after 500 mg p.o. were approximately 11.3 μg/g and were reached between 4 and 6 hours after administration. The concentrations in the lungs consistently exceeded those in plasma.



Penetration into Blister Fluid



Maximum levofloxacin concentrations of about 4.0 and 6.7 μg/ml in the blister fluid were reached 2 - 4 hours after administration following 3 days dosing at 500 mg once or twice daily, respectively.



Penetration into Cerebro-Spinal Fluid



Levofloxacin has poor penetration into cerebro-spinal fluid.



Penetration into prostatic tissue



After administration of oral 500mg levofloxacin once a day for three days, the mean concentrations in prostatic tissue were 8.7 µg/g, 8.2 µg/g and 2.0 µg/g respectively after 2 hours, 6 hours and 24 hours; the mean prostate/plasma concentration ratio was 1.84.



Concentration in urine



The mean urine concentrations 8 - 12 hours after a single oral dose of 150 mg, 300 mg or 500 mg levofloxacin were 44 mg/L, 91 mg/L and 200 mg/L, respectively.



Biotransformation



Levofloxacin is metabolised to a very small extent, the metabolites being desmethyl-levofloxacin and levofloxacin N-oxide. These metabolites account for < 5 % of the dose excreted in urine. Levofloxacin is stereochemically stable and does not undergo chiral inversion.



Elimination



Following oral and intravenous administration of levofloxacin, it is eliminated relatively slowly from the plasma (t½: 6 - 8 h). Excretion is primarily by the renal route > 85 % of the administered dose).



There are no major differences in the pharmacokinetics of levofloxacin following intravenous and oral administration, suggesting that the oral and intravenous routes are interchangeable.



Linearity



Levofloxacin obeys linear pharmacokinetics over a range of 50 to 600 mg.



Subjects with renal insufficiency



The pharmacokinetics of levofloxacin are affected by renal impairment. With decreasing renal function renal elimination and clearance are decreased, and elimination half-lives increased as shown in the table below:
















Clcr [ml/min]




< 20




20 - 40




50 - 80




ClR [ml/min]




13




26




57




t1/2 [h]




35




27




9



Elderly subjects



There are no significant differences in levofloxacin kinetics between young and elderly subjects, except those associated with differences in creatinine clearance.



Gender differences



Separate analysis for male and female subjects showed small to marginal gender differences in levofloxacin pharmacokinetics. There is no evidence that these gender differences are of clinical relevance.



5.3 Preclinical Safety Data



During repeat-dose studies, common observations included reduced food consumption and minor alterations in haematological and biochemical parameters at 200 mg/kg/day in the rat and reduced body weight, saliv

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