Levofloxacin

11 DESCRIPTION Levofloxacin tablets, USP are synthetic antibacterial agents for oral administration. Chemically, levofloxacin, a chiral fluorinated carboxyquinolone, is the pure (-)-(S)-enantiomer of the racemic drug substance ofloxacin. The chemical name is (-)-(S)-9-fluoro-2,3-dihydro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-7H-pyrido [1,2,3-de]-1,4-benzoxazine-6-carboxylic acid hemihydrate. Figure 1: The Chemical Structure of Levofloxacin, USP The molecular formula is C18H20FN3O4 • 1⁄2 H2O and the molecular weight is 370.38. Levofloxacin, USP is a light yellowish-white to yellow-white crystals or crystalline powder. The molecule exists as a zwitterion at the pH conditions in the small intestine. The data demonstrate that from pH 0.6 to 5.8, the solubility of levofloxacin, USP is essentially constant (approximately 100 mg/mL). Levofloxacin, USP is considered soluble to freely soluble in this pH range, as defined by USP nomenclature. Above pH 5.8, the solubility increases rapidly to its maximum at pH 6.7 (272 mg/mL) and is considered freely soluble in this range. Above pH 6.7, the solubility decreases and reaches a minimum value (about 50 mg/mL) at a pH of approximately 6.9. Levofloxacin, USP has the potential to form stable coordination compounds with many metal ions. This in vitro chelation potential has the following formation order: Al+3>Cu+2>Zn+2>Mg+2>Ca+2. Levofloxacin Tablets, USP are available as film-coated tablets and contain the following inactive ingredients: • 250 mg: croscarmellose sodium, hypromellose, iron oxide red, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, povidone and titanium dioxide. • 500 mg: croscarmellose sodium, hypromellose, iron oxide red, iron oxide yellow magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, povidone and titanium dioxide. • 750 mg: croscarmellose sodium, hypromellose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, povidone and titanium dioxide. Levofloxacin tablets, USP meets USP Dissolution Test 2. levofloxacinfigure1

1 INDICATIONS & USAGE Levofloxacin is a fluoroquinolone antibacterial indicated in adults (18 years of age and older) with infections caused by designated, susceptible bacteria and in pediatric patients where indicated (1, 12.4). • Pneumonia: Nosocomial (1.1) and Community Acquired (1.2, 1.3) • Skin and Skin Structure Infections (SSSI): Complicated (1.4) and Uncomplicated (1.5) • Chronic bacterial prostatitis (1.6) • Inhalational Anthrax, Post-Exposure in adult and pediatric patients (1.7) • Plague in adult and pediatric patients (1.8) • Urinary Tract Infections (UTI): Complicated (1.9, 1.10) and Uncomplicated (1.12) • Acute Pyelonephritis (1.11) • Acute Bacterial Exacerbation of Chronic Bronchitis (1.13) • Acute Bacterial Sinusitis (1.14) Usage To reduce the development of drug-resistant bacteria and maintain the effectiveness of levofloxacin and other antibacterial drugs, levofloxacin should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria (1.15). 1.1 Nosocomial Pneumonia Levofloxacin tablets are indicated in adult patients for the treatment of nosocomial pneumonia due to methicillin-susceptible Staphylococcus aureus, Pseudomonas aeruginosa, Serratia marcescens, Escherichia coli, Klebsiella pneumoniae, Haemophilus influenzae, or Streptococcus pneumoniae. Adjunctive therapy should be used as clinically indicated. Where Pseudomonas aeruginosa is a documented or presumptive pathogen, combination therapy with an anti-pseudomonal β-lactam is recommended [see Clinical Studies ( 14.1) ]. 1.2 Community-Acquired Pneumonia: 7 to 14 day Treatment Regimen Levofloxacin tablets are indicated in adult patients for the treatment of community-acquired pneumonia due to methicillin-susceptible Staphylococcus aureus, Streptococcus pneumoniae (including multi-drug-resistant Streptococcus pneumoniae [MDRSP]), Haemophilus influenzae, Haemophilus parainfluenzae, Klebsiella pneumoniae, Moraxella catarrhalis, Chlamydophila pneumoniae, Legionella pneumophila, or Mycoplasma pneumoniae [see Dosage and Administration (2.1) and Clinical Studies ( 14.2)]. MDRSP isolates are isolates resistant to two or more of the following antibacterials: penicillin (MIC ≥2 mcg/mL), 2nd generation cephalosporins, e.g., cefuroxime, macrolides, tetracyclines and trimethoprim/sulfamethoxazole. 1.3 Community-Acquired Pneumonia: 5-day Treatment Regimen Levofloxacin tablets are indicated in adult patients for the treatment of community-acquired pneumonia due to Streptococcus pneumoniae (excluding multi-drug-resistant isolates [MDRSP]), Haemophilus influenzae, Haemophilus parainfluenzae, Mycoplasma pneumoniae, or Chlamydophila pneumoniae [see Dosage and Administration ( 2.1 ) and Clinical Studies ( 14.3)]. 1.4 Complicated Skin and Skin Structure Infections Levofloxacin tablets are indicated in adult patients for the treatment of complicated skin and skin structure infections due to methicillin-susceptible Staphylococcus aureus, Enterococcus faecalis, Streptococcus pyogenes, or Proteus mirabilis [see Clinical Studies ( 14.5)]. 1.5 Uncomplicated Skin and Skin Structure Infections Levofloxacin tablets are indicated in adult patients for the treatment of uncomplicated skin and skin structure infections (mild to moderate) including abscesses, cellulitis, furuncles, impetigo, pyoderma, wound infections, due to methicillin-susceptible Staphylococcus aureus, or Streptococcus pyogenes. 1.6 Chronic Bacterial Prostatitis Levofloxacin tablets are indicated in adult patients for the treatment of chronic bacterial prostatitis due to Escherichia coli, Enterococcus faecalis, or methicillin-susceptible Staphylococcus epidermidis [see Clinical Studies ( 14.6 )]. 1.7 Inhalational Anthrax (Post-Exposure) Levofloxacin tablets are indicated for inhalational anthrax (post-exposure) to reduce the incidence or progression of disease following exposure to aerosolized Bacillus anthracis in adults and pediatric patients, 6 months of age and older [ see Dosage and Administration ( 2.2)]. The effectiveness of levofloxacin tablets is based on plasma concentrations achieved in humans, a surrogate endpoint reasonably likely to predict clinical benefit. Levofloxacin tablets have not been tested in humans for the post-exposure prevention of inhalation anthrax. The safety of levofloxacin tablets in adults for durations of therapy beyond 28 days or in pediatric patients for durations of therapy beyond 14 days has not been studied. Prolonged levofloxacin tablets therapy should only be used when the benefit outweighs the risk [see Clinical Studies ( 14.9 )]. 1.8 Plague Levofloxacin tablets are indicated for treatment of plague, including pneumonic and septicemic plague, due to Yersinia pestis (Y. pestis) and prophylaxis for plague in adults and pediatric patients, 6 months of age and older [see Dosage and Administration ( 2.2 )]. Efficacy studies of levofloxacin tablets could not be conducted in humans with plague for ethical and feasibility reasons. Therefore, approval of this indication was based on an efficacy study conducted in animals [see Clinical Studies ( 14.10)]. 1.9 Complicated Urinary Tract Infections: 5-day Treatment Regimen Levofloxacin tablets are indicated in adult patients for the treatment of complicated urinary tract infections due to Escherichia coli, Klebsiella pneumoniae, or Proteus mirabilis [see Clinical Studies ( 14.7 )]. 1.10 Complicated Urinary Tract Infections: 10-day Treatment Regimen Levofloxacin tablets are indicated in adult patients for the treatment of complicated urinary tract infections (mild to moderate) due to Enterococcus faecalis, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, or Pseudomonas aeruginosa [see Clinical Studies (14.8) ]. 1.11 Acute Pyelonephritis: 5 or 10-day Treatment Regimen Levofloxacin tablets are indicated in adult patients for the treatment of acute pyelonephritis caused by Escherichia coli, including cases with concurrent bacteremia [see Clinical Studies (14.7 , 14.8 )]. 1.12 Uncomplicated Urinary Tract Infections Levofloxacin tablets are indicated in adult patients for the treatment of uncomplicated urinary tract infections (mild to moderate) due to Escherichia coli, Klebsiella pneumoniae, or Staphylococcus saprophyticus. Because fluoroquinolones, including levofloxacin tablets, have been associated with serious adverse reactions [see Warnings and Precautions ( 5.1 to 5.15 )] and for some patients uncomplicated urinary tract infection is self-limiting, reserve levofloxacin for treatment of uncomplicated urinary tract infections in patients who have no alternative treatment options. 1.13 Acute Bacterial Exacerbation of Chronic Bronchitis Levofloxacin tablets are indicated in adult patients for the treatment of acute bacterial exacerbation of chronic bronchitis (ABECB) due to methicillin-susceptible Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, Haemophilus parainfluenzae, or Moraxella catarrhalis. Because fluoroquinolones, including levofloxacin tablets, have been associated with serious adverse reactions [see Warnings and Precautions ( 5.1 to 5.15 )] and for some patients ABECB is self-limiting, reserve levofloxacin tablets for treatment of ABECB in patients who have no alternative treatment options. 1.14 Acute Bacterial Sinusitis: 5-day and 10 to 14 day Treatment Regimens Levofloxacin tablets are indicated in adult patients for the treatment of acute bacterial sinusitis (ABS) due to Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis [see Clinical Studies ( 14.4)]. Because fluoroquinolones, including levofloxacin tablets, have been associated with serious adverse reactions [see Warnings and Precautions ( 5.1 to 5.15 )] and for some patients ABS is self-limiting, reserve levofloxacin tablets for treatment of ABS in patients who have no alternative treatment options. 1.15 Usage To reduce the development of drug-resistant bacteria and maintain the effectiveness of levofloxacin tablets and other antibacterial drugs, levofloxacin tablets should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy. Culture and susceptibility testing Appropriate culture and susceptibility tests should be performed before treatment in order to isolate and identify organisms causing the infection and to determine their susceptibility to levofloxacin [see Microbiology ( 12.4)] . Therapy with levofloxacin tablets may be initiated before results of these tests are known; once results become available, appropriate therapy should be selected. As with other drugs in this class, some isolates of Pseudomonas aeruginosa may develop resistance fairly rapidly during treatment with levofloxacin tablets. Culture and susceptibility testing performed periodically during therapy will provide information about the continued susceptibility of the pathogens to the antimicrobial agent and also the possible emergence of bacterial resistance.

5 WARNINGS AND PRECAUTIONS Anaphylactic reactions and allergic skin reactions, serious, occasionally fatal, may occur after first dose ( 4 , 5.7 ) Hematologic (including agranulocytosis, thrombocytopenia), and renal toxicities may occur after multiple doses ( 5.6 ) Hepatotoxicity: Severe, and sometimes fatal, hepatoxicity has been reported. Discontinue immediately if signs and symptoms of hepatitis occur ( 5.8 ) Clostridium difficile -associated colitis: evaluate if diarrhea occurs ( 5.10 ) Prolongation of the QT interval and isolated cases of torsade de pointes have been reported. Avoid use in patients with known prolongation, those with hypokalemia, and with other drugs that prolong the QT interval ( 5.11 , 8.5 ) 5.1 Disabling and Potentially Irreversible Serious Adverse Reactions Including Tendinitis and Tendon Rupture, Peripheral Neuropathy, and Central Nervous System Effects Fluoroquinolones, including levofloxacin, have been associated with disabling and potentially irreversible serious adverse reactions from different body systems that can occur together in the same patient. Commonly seen adverse reactions include tendinitis, tendon rupture, arthralgia, myalgia, peripheral neuropathy, and central nervous system effects (hallucinations, anxiety, depression, insomnia, severe headaches, and confusion). These reactions can occur within hours to weeks after starting levofloxacin. Patients of any age or without pre-existing risk factors have experienced these adverse reactions [see Warnings and Precautions (5.2 , 5.3 , 5.4 )]. Discontinue levofloxacin immediately at the first signs or symptoms of any serious adverse reaction. In addition, avoid the use of fluoroquinolones, including levofloxacin, in patients who have experienced any of these serious adverse reactions associated with fluoroquinolones. 5.2 Tendinopathy and Tendon Rupture Fluoroquinolones, including levofloxacin, have been associated with an increased risk of tendinitis and tendon rupture in all ages [see Warnings and Precautions ( 5.1) and Adverse Reactions ( 6.2)]. This adverse reaction most frequently involves the Achilles tendon and has also been reported with the rotator cuff (the shoulder), the hand, the biceps, the thumb, and other tendon sites. Tendinitis or tendon rupture can occur within hours or days of starting levofloxacin or as long as several months after completion of fluoroquinolone therapy. Tendinitis and tendon rupture can occur bilaterally. The risk of developing fluoroquinolone-associated tendinitis and tendon rupture is increased in patients over 60 years of age, in those taking corticosteroid drugs, and in patients with kidney, heart or lung transplants. Other factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. Tendinitis and tendon rupture have been reported in patients taking fluoroquinolones who do not have the above risk factors. Discontinue levofloxacin immediately if the patient experiences pain, swelling, inflammation or rupture of a tendon. Patients should be advised to rest at the first sign of tendinitis or tendon rupture, and to contact their healthcare provider regarding changing to a non-quinolone antimicrobial drug. Avoid levofloxacin in patients who have a history of tendon disorders or tendon rupture [see Adverse Reactions ( 6.3 ) and Patient Counseling Information ( 17 )]. 5.3 Peripheral Neuropathy Fluoroquinolones, including levofloxacin, have been associated with an increased risk of peripheral neuropathy. Cases of sensory or sensorimotor axonal polyneuropathy affecting small and/or large axons resulting in paresthesias, hypoesthesias, dysesthesias and weakness have been reported in patients receiving fluoroquinolones, including levofloxacin. Symptoms may occur soon after initiation of levofloxacin and may be irreversible in some patients [see Warnings and Precautions ( 5.1) and Adverse Reactions ( 6.1, 6.2 )]. Discontinue levofloxacin immediately if the patient experiences symptoms of neuropathy including pain, burning, tingling, numbness, and/or weakness or other alterations of sensation including light touch, pain, temperature, position sense, and vibratory sensation. Avoid fluoroquinolones, including levofloxacin, in patients who have previously experienced peripheral neuropathy [see Adverse Reactions ( 6) and Patient Counseling Information ( 17)]. 5.4 Central Nervous System Effects Psychiatric Adverse Reactions Fluoroquinolones, including levofloxacin, havebeenassociated with an increased risk of psychiatric adverse reactions, including: toxic psychoses, hallucinations, or paranoia; depression, or suicidal thoughts; anxiety,agitation, restlessness, or nervousness; confusion, delirium, disorientation, or disturbances in attention; insomnia or nightmares; memory impairment. Attempted or completed suicide have been reported, especially in patients with a medical history of depression, or an underlying risk factor for depression. These reactions may occurfollowingthe first dose. If these reactions occur in patients receiving levofloxacin, discontinue levofloxacin and institute appropriate measures. Central Nervous SystemAdverseReactions Fluoroquinolones, including levofloxacin, have beenassociated with an increased risk of seizures (convulsions), increased intracranial pressure (including pseudotumor cerebri), tremors, and lightheadedness. As with other fluoroquinolones, levofloxacin should be used with caution in patients with a knownor suspected central nervous system (CNS) disorder that may predispose them to seizures or lower the seizure threshold (e.g., severe cerebral arteriosclerosis, epilepsy) or in the presence of other risk factors that may predispose them to seizures or lower the seizurethreshold (e.g., certain drug therapy, renal dysfunction). If these reactions occur in patients receiving levofloxacin discontinue levofloxacin and institute appropriatemeasures [see Adverse Reactions ( 6 ), Drug Interactions ( 7.4, 7.5), and Patient Counseling Information (17)]. 5.5 Exacerbation of Myasthenia Gravis Fluoroquinolones, including levofloxacin, have neuromuscular blocking activity and may exacerbate muscle weakness in patients with myasthenia gravis. Postmarketing serious adverse reactions including deaths and requirement for ventilatory support, have been associated with fluoroquinolone use in patients with myasthenia gravis. Avoid levofloxacin in patients with a known history of myasthenia gravis [see Adverse Reactions ( 6.3) and Patient Counseling Information ( 17 )]. 5.6 Other Serious and Sometimes Fatal Adverse Reactions Other serious and sometimes fatal adverse reactions, some due to hypersensitivity, and some due to uncertain etiology, have been reported rarely in patients receiving therapy with fluoroquinolones, including levofloxacin. These events may be severe and generally occur following the administration of multiple doses. Clinical manifestations may include one or more of the following: • fever, rash, or severe dermatologic reactions (e.g., toxic epidermal necrolysis, Stevens-Johnson Syndrome); • vasculitis; arthralgia; myalgia; serum sickness; • allergic pneumonitis; • interstitial nephritis; acute renal insufficiency or failure; • hepatitis; jaundice; acute hepatic necrosis or failure; • anemia, including hemolytic and aplastic; thrombocytopenia, including thrombotic thrombocytopenic purpura; leukopenia; agranulocytosis; pancytopenia; and/or other hematologic abnormalities. Discontinue levofloxacin immediately at the first appearance of skin rash, jaundice, or any other sign of hypersensitivity and institute supportive measures [see Adverse Reactions ( 6 ) and Patient Counseling Information ( 17)]. 5.7 Hypersensitivity Reactions Serious and occasionally fatal hypersensitivity and/or anaphylactic reactions have been reported in patients receiving therapy with fluoroquinolones, including levofloxacin. These reactions often occur following the first dose. Some reactions have been accompanied by cardiovascular collapse, hypotension/shock, seizure, loss of consciousness, tingling, angioedema (including tongue, laryngeal, throat, or facial edema/swelling), airway obstruction (including bronchospasm, shortness of breath, and acute respiratory distress), dyspnea, urticaria, itching, and other serious skin reactions. Levofloxacin should be discontinued immediately at the first appearance of a skin rash or any other sign of hypersensitivity. Serious acute hypersensitivity reactions may require treatment with epinephrine and other resuscitative measures, including oxygen, intravenous fluids, antihistamines, corticosteroids, pressor amines, and airway management, as clinically indicated [see Adverse Reactions ( 6) and Patient Counseling Information ( 17) ]. 5.8 Hepatotoxicity Post-marketing reports of severe hepatotoxicity (including acute hepatitis and fatal events) have been received for patients treated with levofloxacin. No evidence of serious drug-associated hepatotoxicity was detected in clinical trials of over 7,000 patients. Severe hepatotoxicity generally occurred within 14 days of initiation of therapy and most cases occurred within 6 days. Most cases of severe hepatotoxicity were not associated with hypersensitivity [see Warnings and Precautions ( 5.6 )]. The majority of fatal hepatotoxicity reports occurred in patients 65 years of age or older and most were not associated with hypersensitivity. Levofloxacin should be discontinued immediately if the patient develops signs and symptoms of hepatitis [see Adverse Reactions ( 6 ) and Patient Counseling Information ( 17)]. 5.9 Risk of Aortic Aneurysm and Dissection Fluoroquinolones,includinglevofloxacin, have been associated with aortic aneurysm and dissection. Findings from epidemiologic studies show a consistently increased risk of hospitalizationfor aortic aneurysm or dissection within two months following use of a fluoroquinolone antibacterial drug. The annual estimated background risk of aortic aneurysm is as high asapproximately300 aortic aneurysm events per 100,000 persons at the highest risk (e.g., age greater than 85 years). The evidence shows the potential for a 2-fold increasedrisk over the background risk following fluoroquinolone exposure and was based on a small number of cases, mostly in older patients. The cause for the risk of aortic aneurysm ordissectionhas not been identified, but the available data suggest that use of fluoroquinolones may contribute in the short term to aneurysm progression. Inpatientswith a known aortic aneurysm or patients who are at greater risk for aortic aneurysms, reserve levofloxacin for use only when there are no alternative antibacterial treatmentsavailable. 5.10 Clostridium difficile -Associated Diarrhea Clostridium difficile -associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents, including levofloxacin, and may range in severity from mild diarrhea to fatal colitis. Treatment with antibacterial agents alters the normal flora of the colon leading to overgrowth of C. difficile. C. difficile produces toxins A and B which contribute to the development of CDAD. Hypertoxin producing strains of C. difficile cause increased morbidity and mortality, as these infections can be refractory to antimicrobial therapy and may require colectomy. CDAD must be considered in all patients who present with diarrhea following antibiotic use. Careful medical history is necessary since CDAD has been reported to occur over two months after the administration of antibacterial agents. If CDAD is suspected or confirmed, ongoing antibiotic use not directed against C. difficile may need to be discontinued. Appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C. difficile , and surgical evaluation should be instituted as clinically indicated [see Adverse Reactions ( 6.2 ) and Patient Counseling Information ( 17)]. 5.11 Prolongation of the QT Interval Some fluoroquinolones, including levofloxacin, have been associated with prolongation of the QT interval on the electrocardiogram and infrequent cases of arrhythmia. Rare cases of torsade de pointes have been spontaneously reported during postmarketing surveillance in patients receiving fluoroquinolones, including levofloxacin. Levofloxacin should be avoided in patients with known prolongation of the QT interval, patients with uncorrected hypokalemia, and patients receiving Class IA (quinidine, procainamide), or Class III (amiodarone, sotalol) antiarrhythmic agents. Elderly patients may be more susceptible to drug-associated effects on the QT interval [see Adverse Reactions ( 6.3 ) , Use in Specific Populations ( 8.5), and Patient Counseling Information ( 17 )]. 5.12 Musculoskeletal Disorders in Pediatric Patients and Arthropathic Effects in Animals Levofloxacin is indicated in pediatric patients (6 months of age and older) only for the prevention of inhalational anthrax (post-exposure) and for plague [see Indications and Usage ( 1.7 , 1.8 )]. An increased incidence of musculoskeletal disorders (arthralgia, arthritis, tendinopathy, and gait abnormality) compared to controls has been observed in pediatric patients receiving levofloxacin [see Use in Specific Populations ( 8.4 )]. In immature rats and dogs, the oral and intravenous administration of levofloxacin resulted in increased osteochondrosis. Histopathological examination of the weight-bearing joints of immature dogs dosed with levofloxacin revealed persistent lesions of the cartilage. Other fluoroquinolones also produce similar erosions in the weight-bearing joints and other signs of arthropathy in immature animals of various species [see Animal Toxicology and/or Pharmacology ( 13.2 )]. 5.13 Blood Glucose Disturbances Fluoroquinolones, including levofloxacin, have been associated with disturbances of blood glucose, including symptomatic hyperglycemia and hypoglycemia, usually in diabetic patients receiving concomitant treatment with an oral hypoglycemic agent (e.g., glyburide) or with insulin. In these patients, careful monitoring of blood glucose is recommended. Severe cases of hypoglycemia resulting in coma or death havebeen reported. If a hypoglycemic reaction occurs in a patient being treated with levofloxacin, discontinue levofloxacin and initiate appropriate therapy immediately [see Adverse Reactions ( 6.2 ), Drug Interactions ( 7.3) and Patient Counseling Information ( 17) ]. 5.14 Photosensitivity/Phototoxicity Moderate to severe photosensitivity/phototoxicity reactions, the latter of which may manifest as exaggerated sunburn reactions (e.g., burning, erythema, exudation, vesicles, blistering, edema) involving areas exposed to light (typically the face, “V” area of the neck, extensor surfaces of the forearms, dorsa of the hands), can be associated with the use of fluoroquinolones after sun or UV light exposure. Therefore, excessive exposure to these sources of light should be avoided. Drug therapy should be discontinued if photosensitivity/phototoxicity occurs [see Adverse Reactions ( 6.3) and Patient Counseling Information ( 17)]. 5.15 Development of Drug Resistant Bacteria Prescribing levofloxacin 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 [see Patient Counseling Information (17)].

6 ADVERSE REACTIONS The most common reactions (≥3%) were nausea, headache, diarrhea, insomnia, constipation and dizziness ( 6.2 ). To report SUSPECTED ADVERSE REACTIONS, contact Hetero Labs Limited at 1-866-495-1995 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch . 6.1 Serious and Otherwise Important Adverse Reactions The following serious and otherwise important adverse drug reactions are discussed in greater detail in other sections of labeling: • Disabling and Potentially Irreversible Serious Adverse Reactions [ see Warnings and Precautions (5.1)] • Tendinitis and Tendon Rupture [see Warnings and Precautions ( 5.2)] • Peripheral Neuropathy [see Warnings and Precautions (5.3)] • Central Nervous System Effects [see Warnings and Precautions ( 5.4)] • Exacerbation of Myasthenia Gravis [see Warnings and Precautions ( 5.5)] • Other Serious and Sometimes Fatal Reactions [see Warnings and Precautions ( 5.6)] • Hypersensitivity Reactions [see Warnings and Precautions (5.7)] • Hepatotoxicity [see Warnings and Precautions ( 5.8)] • Risk of Aortic Aneurysm and Dissection [see Warnings and Precautions ( 5.9 )] • Clostridium difficile-Associated Diarrhea [see Warnings and Precautions ( 5.10 )] • Prolongation of the QT Interval [see Warnings and Precautions ( 5.11 )] • Musculoskeletal Disorders in Pediatric Patients [see Warnings and Precautions ( 5.12 )] • Blood Glucose Disturbances [see Warnings and Precautions ( 5.13 )] • Photosensitivity/Phototoxicity [see Warnings and Precautions ( 5.14 )] • Development of Drug Resistant Bacteria [see Warnings and Precautions ( 5.15 )] Crystalluria and cylindruria have been reported with quinolones, including levofloxacin. Therefore, adequate hydration of patients receiving levofloxacin should be maintained to prevent the formation of a highly concentrated urine [see Dosage and Administration ( 2.5 )]. 6.2 Clinical Trial Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice. The data described below reflect exposure to levofloxacin in 7537 patients in 29 pooled Phase 3 clinical trials. The population studied had a mean age of 50 years (approximately 74% of the population was < 65 years of age), 50% were male, 71% were Caucasian, 19% were Black. Patients were treated with levofloxacin for a wide variety of infectious diseases [see Indications and Usage (1)]. Patients received levofloxacin doses of 750 mg once daily, 250 mg once daily, or 500 mg once or twice daily. Treatment duration was usually 3 to 14 days, and the mean number of days on therapy was 10 days. The overall incidence, type and distribution of adverse reactions was similar in patients receiving levofloxacin doses of 750 mg once daily, 250 mg once daily, and 500 mg once or twice daily. Discontinuation of levofloxacin due to adverse drug reactions occurred in 4.3% of patients overall, 3.8% of patients treated with the 250 mg and 500 mg doses and 5.4% of patients treated with the 750 mg dose. The most common adverse drug reactions leading to discontinuation with the 250 and 500 mg doses were gastrointestinal (1.4%), primarily nausea (0.6%); vomiting (0.4%); dizziness (0.3%); and headache (0.2%). The most common adverse drug reactions leading to discontinuation with the 750 mg dose were gastrointestinal (1.2%), primarily nausea (0.6%), vomiting (0.5%); dizziness (0.3%); and headache (0.3%). Adverse reactions occurring in ≥1% of levofloxacin-treated patients and less common adverse reactions, occurring in 0.1 to <1% of levofloxacin-treated patients, are shown in Table 4 and Table 5, respectively. The most common adverse drug reactions (≥3%) are nausea, headache, diarrhea, insomnia, constipation, and dizziness. Table 4:Common (≥1%) Adverse Reactions Reported in Clinical Trials with Levofloxacin System/Organ Class Adverse Reaction % (N=7537) Infections and Infestations moniliasis 1 Psychiatric Disorders insomnia * [see Warnings and Precautions ( 5.4 )] 4 Nervous System Disorders headache dizziness [see Warnings and Precautions ( 5.4 )] 6 3 Respiratory, Thoracic and Mediastinal Disorders dyspnea [see Warnings and Precautions ( 5.7 )] 1 Gastrointestinal Disorders nausea diarrhea constipation abdominal pain vomiting dyspepsia 7 5 3 2 2 2 Skin and Subcutaneous Tissue Disorders rash [see Warnings and Precautions ( 5.7 )] pruritus 2 1 Reproductive System and Breast Disorders vaginitis 1 † General Disorders and Administration Site Conditions edema injection site reaction chest pain 1 1 1 * N = 7274 † N=3758 (women) # pool of studies included IV and oral administration Table 5: Less Common (0.1 to 1%) Adverse Reactions Reported in Clinical Trials with Levofloxacin (N=7537) System/Organ Class Adverse Reaction Infections and Infestations genital moniliasis Blood and Lymphatic System Disorders anemiathrombocytopenia granulocytopenia [see Warnings and Precautions ( 5.6 )] Immune System Disorders allergic reaction [see Warnings and Precautions ( 5.6 , 5.7 )] Metabolism and Nutrition Disorders hyperglycemia hypoglycemia [see Warnings and Precautions ( 5.13 )] hyperkalemia Psychiatric Disorders anxiety agitation confusion depression hallucination nightmare * [see Warnings and Precautions ( 5.4 )] sleep disorder * anorexia abnormal dreaming * Nervous System Disorders tremorconvulsions [see Warnings and Precautions ( 5.4 )] paresthesia [see Warnings and Precautions ( 5.3 )] vertigo hypertonia hyperkinesias abnormal gait somnolence * syncope Respiratory, Thoraic and Mediastinal Disorders epistaxis Cardiac Disorders cardiac arrestpalpitation ventricular tachycardia ventricular arrhythmia Vascular Disorders phlebitis Gastrointestinal Disorders gastritisstomatitis pancreatitis esophagitis gastroenteritis glossitis pseudomembranous/ C. difficile colitis [see Warnings and Precautions ( 5.10 )] Hepatobiliary Disorders abnormal hepatic functionincreased hepatic enzymes increased alkaline phosphatase Skin and Subcutaneous Tissue Disorders urticaria [see Warnings and Precautions ( 5.7 )] Musculoskeletal and Connective Tissue Disorders arthralgiatendinitis [see Warnings and Precautions ( 5.2 )] myalgia skeletal pain Renal and Urinary Disorders abnormal renal functionacute renal failure [see Warnings and Precautions ( 5.6 )] * N = 7274 In clinical trials using multiple-dose therapy, ophthalmologic abnormalities, including cataracts and multiple punctate lenticular opacities, have been noted in patients undergoing treatment with quinolones, including levofloxacin. The relationship of the drugs to these events is not presently established. 6.3 Postmarketing Experience Table 6 lists adverse reactions that have been identified during post-approval use of levofloxacin. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Table 6: Postmarketing Reports Of Adverse Drug Reactions System/Organ Class Adverse Reaction Blood and Lymphatic System Disorders pancytopenia aplastic anemia leukopenia hemolytic anemia [see Warnings and Precautions ( 5.6 )] eosinophilia Immune System Disorders hypersensitivity reactions, sometimes fatal including: anaphylactic/anaphylactoid reactions anaphylactic shock angioneurotic edema serum sickness [see Warnings and Precautions ( 5.6 , 5.7 )] Psychiatric Disorders psychosis paranoia isolated reports of suicide attempt and suicidal ideation [see Warnings and Precautions ( 5.4 )] Nervous System Disorders exacerbation of myasthenia gravis [see Warnings and Precautions (5.5 )] anosmia ageusia parosmia dysgeusia peripheral neuropathy (may be irreversible) [see Warnings and Precautions ( 5.3 )] isolated reports of encephalopathy abnormal electroencephalogram (EEG) dysphonia pseudotumor cerebri [see Warnings and Precautions ( 5.4 )] Eye Disorders uveitis vision disturbance, including diplopia visual acuity reduced vision blurred scotoma Ear and Labyrinth Disorders hypoacusis tinnitus Cardiac Disorders isolated reports of torsade de pointes electrocardiogram QT prolonged [see Warnings and Precautions ( 5.11 )] tachycardia Vascular Disorders vasodilatation Respiratory, Thoracic and Mediastinal Disorders isolated reports of allergic pneumonitis [see Warnings and Precautions ( 5.6 )] Hepatobiliary Disorders hepatic failure (including fatal cases) hepatitis jaundice [see Warnings and Precautions ( 5.6 ), ( 5.8 )] Skin and Subcutaneous Tissue Disorders bullous eruptions to include: Stevens-Johnson Syndrome toxic epidermal necrolysis erythema multiforme [see Warnings and Precautions ( 5.6 )] photosensitivity/phototoxicity reaction [see Warnings and Precautions ( 5.14 )] leukocytoclastic vasculitis Musculoskeletal and Connective Tissue Disorders tendon rupture [see Warnings and Precautions ( 5.2 )] muscle injury, including rupture rhabdomyolysis Renal and Urinary Disorders interstitial nephritis [see Warnings and Precautions ( 5.6 )] General Disorders and Administration Site Conditions multi-organ failure pyrexia Investigations prothrombin time prolonged international normalized ratio prolonged muscle enzymes increased

7 DRUG INTERACTIONS Interacting Drug Interaction Multivalent cation-containing products including antacids, metal cations or didanosine Absorption of levofloxacin is decreased when the tablets are taken within 2 hours of these products. (2.4, 7.1) Warfarin Effect may be enhanced. Monitor prothrombin time, INR and watch for bleeding (7.2) Antidiabetic agents Carefully monitor blood glucose (5.13, 7.3) 7.1 Chelation Agents: Antacids, Sucralfate, Metal Cations, Multivitamins While the chelation by divalent cations is less marked than with other fluoroquinolones, concurrent administration of levofloxacin tablets with antacids containing magnesium, or aluminum, as well as sucralfate, metal cations such as iron, and multivitamin preparations with zinc may interfere with the gastrointestinal absorption of levofloxacin, resulting in systemic levels considerably lower than desired. Tablets with antacids containing magnesium, aluminum, as well as sucralfate, metal cations such as iron, and multivitamin preparations with zinc or didanosine may substantially interfere with the gastrointestinal absorption of levofloxacin, resulting in systemic levels considerably lower than desired. These agents should be taken at least two hours before or two hours after oral levofloxacin administration. 7.2 Warfarin No significant effect of levofloxacin on the peak plasma concentrations, AUC, and other disposition parameters for R- and S- warfarin was detected in a clinical study involving healthy volunteers. Similarly, no apparent effect of warfarin on levofloxacin absorption and disposition was observed. However, there have been reports during the postmarketing experience in patients that levofloxacin enhances the effects of warfarin. Elevations of the prothrombin time in the setting of concurrent warfarin and levofloxacin use have been associated with episodes of bleeding. Prothrombin time, International Normalized Ratio (INR), or other suitable anticoagulation tests should be closely monitored if levofloxacin is administered concomitantly with warfarin. Patients should also be monitored for evidence of bleeding [see Adverse Reactions ( 6.3) and Patient Counseling Information ( 17)]. 7.3 Antidiabetic Agents Disturbances of blood glucose, including hyperglycemia and hypoglycemia, have been reported in patients treated concomitantly with fluoroquinolones and an antidiabetic agent. Therefore, careful monitoring of blood glucose is recommended when these agents are co-administered [see Warnings and Precautions ( 5.13 ), Adverse Reactions ( 6.2), and Patient Counseling Information ( 17)]. 7.4 Non-Steroidal Anti-Inflammatory Drugs The concomitant administration of a non-steroidal anti-inflammatory drug with a fluoroquinolone, including levofloxacin, may increase the risk of CNS stimulation and convulsive seizures [see Warnings and Precautions ( 5.4 )]. 7.5 Theophylline No significant effect of levofloxacin on the plasma concentrations, AUC, and other disposition parameters for theophylline was detected in a clinical study involving healthy volunteers. Similarly, no apparent effect of theophylline on levofloxacin absorption and disposition was observed. However, concomitant administration of other fluoroquinolones with theophylline has resulted in prolonged elimination half-life, elevated serum theophylline levels, and a subsequent increase in the risk of theophylline-related adverse reactions in the patient population. Therefore, theophylline levels should be closely monitored and appropriate dosage adjustments made when levofloxacin is co-administered. Adverse reactions, including seizures, may occur with or without an elevation in serum theophylline levels [see Warnings and Precautions ( 5.4)]. 7.6 Cyclosporine No significant effect of levofloxacin on the peak plasma concentrations, AUC, and other disposition parameters for cyclosporine was detected in a clinical study involving healthy volunteers. However, elevated serum levels of cyclosporine have been reported in the patient population when co-administered with some other fluoroquinolones. Levofloxacin C max and k e were slightly lower while T max and t1/2 were slightly longer in the presence of cyclosporine than those observed in other studies without concomitant medication. The differences, however, are not considered to be clinically significant. Therefore, no dosage adjustment is required for levofloxacin or cyclosporine when administered concomitantly. 7.7 Digoxin No significant effect of levofloxacin on the peak plasma concentrations, AUC, and other disposition parameters for digoxin was detected in a clinical study involving healthy volunteers. Levofloxacin absorption and disposition kinetics were similar in the presence or absence of digoxin. Therefore, no dosage adjustment for levofloxacin or digoxin is required when administered concomitantly. 7.8 Probenecid and Cimetidine No significant effect of probenecid or cimetidine on the Cmax of levofloxacin was observed in a clinical study involving healthy volunteers. The AUC and t 1/2 of levofloxacin were higher while CL/F and CLR were lower during concomitant treatment of levofloxacin with probenecid or cimetidine compared to levofloxacin alone. However, these changes do not warrant dosage adjustment for levofloxacin when probenecid or cimetidine is co-administered. 7.9 Interactions with Laboratory or Diagnostic Testing Some fluoroquinolones, including levofloxacin, may produce false-positive urine screening results for opiates using commercially available immunoassay kits. Confirmation of positive opiate screens by more specific methods may be necessary.

8 USE IN SPECIFIC POPULATIONS • Geriatrics: Severe hepatotoxicity has been reported. The majority of reports describe patients 65 years of age or older (5.8, 8.5, 17). May have increased risk of tendinopathy (including rupture), especially with concomitant corticosteroid use (5.2, 8.5, 17). May be more susceptible to prolongation of the QT interval. (5.11, 8.5, 17). • Pediatrics: Musculoskeletal disorders (arthralgia, arthritis, tendinopathy, and gait abnormality) seen in more levofloxacin-treated patients than in comparator. Shown to cause arthropathy and osteochondrosis in juvenile animals (5.12, 8.4, 13.2). Safety in pediatric patients treated for more than 14 days has not been studied. Risk-benefit appropriate only for the treatment of inhalational anthrax (post-exposure) (1.7, 2.2, 8.4, 14.9) and plague (1.8, 2.2, 8.4, 14.10) 8.1 Pregnancy Pregnancy Category C. Levofloxacin was not teratogenic in rats at doses as high as 810 mg/kg/day which corresponds to 9.4 times the highest recommended oral human dose based upon relative body surface area. The oral dose of 810 mg/kg/day to rats caused decreased fetal body weight and increased fetal mortality. No teratogenicity was observed when rabbits were dosed orally as high as 50 mg/kg/day which corresponds to 1.1 times the highest recommended oral human dose based upon relative body surface area. There are, however, no adequate and well-controlled studies in pregnant women. Levofloxacin should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. 8.3 Nursing Mothers Based on data on other fluoroquinolones and very limited data on levofloxacin, it can be presumed that levofloxacin will be excreted in human milk. Because of the potential for serious adverse reactions from levofloxacin in nursing infants, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother. 8.4 Pediatric Use Quinolones, including levofloxacin, cause arthropathy and osteochondrosis in juvenile animals of several species. [see Warnings and Precautions ( 5.12 ) and Animal Toxicology and/or Pharmacology ( 13.2 )]. Inhalational Anthrax (Post-Exposure) Levofloxacin is indicated in pediatric patients 6 months of age and older, for inhalational anthrax (post-exposure). The risk-benefit assessment indicates that administration of levofloxacin to pediatric patients is appropriate. The safety of levofloxacin in pediatric patients treated for more than 14 days has not been studied [see Indications and Usage (1.7), Dosage and Administration ( 2.2 ) and Clinical Studies ( 14.9)]. Plague Levofloxacin is indicated in pediatric patients, 6 months of age and older, for treatment of plague, including pneumonic and septicemic plague due to Yersinia pestis (Y. pestis) and prophylaxis for plague. Efficacy studies of levofloxacin could not be conducted in humans with pneumonic plague for ethical and feasibility reasons. Therefore, approval of this indication was based on an efficacy study conducted in animals. The risk-benefit assessment indicates that administration of levofloxacin to pediatric patients is appropriate [see Indications and Usage ( 1.8), Dosage and Administration ( 2.2) and Clinical Studies ( 14.10 )]. Safety and effectiveness of levofloxacin in pediatric patients below the age of six months have not been established. Pharmacokinetics following intravenous administration The pharmacokinetics of levofloxacin following a single intravenous dose were investigated in pediatric patients ranging in age from six months to 16 years. Pediatric patients cleared levofloxacin faster than adult patients resulting in lower plasma exposures than adults for a given mg/kg dose [see Clinical Pharmacology ( 12.3) and Clinical Studies ( 14.9) ]. Dosage in Pediatric Patients with Inhalational Anthrax or Plague For the recommended levofloxacin tablet dosage in pediatric patients with inhalational anthrax or plague, see Dosage and Administration ( 2.2 ). Levofloxacin Tablets cannot be administered to pediatric patients who weigh less than 30 kg because of the limitations of the available strengths. Alternative formulations of levofloxacin may be considered for pediatric patients who weigh less than 30 kg. Adverse Reactions In clinical trials, 1534 pediatric patients (6 months to 16 years of age) were treated with oral and intravenous levofloxacin. Pediatric patients 6 months to 5 years of age received levofloxacin 10 mg/kg twice a day and pediatric patients greater than 5 years of age received 10 mg/kg once a day (maximum 500 mg per day) for approximately 10 days. Levofloxacin tablets can only be administered to pediatric patients with inhalational anthrax (post-exposure) or plague who are 30 kg or greater due to the limitations of the available strengths [see Dosage and Administration ( 2.2)]. A subset of pediatric patients in the clinical trials (1340 levofloxacin-treated and 893 non-fluoroquinolone-treated) enrolled in a prospective, long-term surveillance study to assess the incidence of protocol-defined musculoskeletal disorders (arthralgia, arthritis, tendinopathy, gait abnormality) during 60 days and 1 year following the first dose of the study drug. Pediatric patients treated with levofloxacin had a significantly higher incidence of musculoskeletal disorders when compared to the non-fluoroquinolone-treated children as illustrated in Table 7. Levofloxacin tablets can only be administered to pediatric patients with inhalational anthrax (post-exposure) or plague who are 30 kg or greater due to the limitations of the available strengths [see Dosage and Administration ( 2.2 )]. Table 7: Incidence of Musculoskeletal Disorders in Pediatric Clinical Trial Follow-up Period Levofloxacin N = 1340 Non-Fluoroquinolone * N = 893 p-value † 60 days 28 (2.1%) 8 (0.9%) p = 0.038 1 year ‡ 46 (3.4%) 16 (1.8%) p = 0.025 * Non-Fluoroquinolone: ceftriaxone, amoxicillin/clavulanate, clarithromycin † 2-sided Fisher’s Exact Test ‡ There were 1199 levofloxacin-treated and 804 non-fluoroquinolone-treated pediatric patients who had a one-year evaluation visit. However, the incidence of musculoskeletal disorders was calculated using all reported events during the specified period for all pediatric patients enrolled regardless of whether they completed the 1-year evaluation visit. Arthralgia was the most frequently occurring musculoskeletal disorder in both treatment groups. Most of the musculoskeletal disorders in both groups involved multiple weight-bearing joints. Disorders were moderate in 8/46 (17%) children and mild in 35/46 (76%) levofloxacin-treated pediatric patients and most were treated with analgesics. The median time to resolution was 7 days for levofloxacin-treated pediatric patients and 9 for non-fluoroquinolone-treated children (approximately 80% resolved within 2 months in both groups). No pediatric patient had a severe or serious disorder and all musculoskeletal disorders resolved without sequelae. Vomiting and diarrhea were the most frequently reported adverse reactions, occurring in similar frequency in the levofloxacin-treated and non-fluoroquinolone-treated pediatric patients. In addition to the adverse reactions reported in pediatric patients in clinical trials, adverse reactions reported in adults during clinical trials or post-marketing experience [see Adverse Reactions ( 6)] may also be expected to occur in pediatric patients. 8.5 Geriatric Use Geriatric patients are at increased risk for developing severe tendon disorders including tendon rupture when being treated with a fluoroquinolone such as levofloxacin. This risk is further increased in patients receiving concomitant corticosteroid therapy. Tendinitis or tendon rupture can involve the Achilles, hand, shoulder, or other tendon sites and can occur during or after completion of therapy; cases occurring up to several months after fluoroquinolone treatment have been reported. Caution should be used when prescribing levofloxacin to elderly patients especially those on corticosteroids. Patients should be informed of this potential side effect and advised to discontinue levofloxacin and contact their healthcare provider if any symptoms of tendinitis or tendon rupture occur [see Boxed Warning; Warnings and Precautions ( 5.2 ); and Adverse Reactions ( 6.3) ]. In Phase 3 clinical trials, 1,945 levofloxacin-treated patients (26%) were ≥ 65 years of age. Of these, 1,081 patients (14%) were between the ages of 65 and 74 and 864 patients (12%) were 75 years or older. No overall differences in safety or effectiveness were observed between these subjects and younger subjects, but greater sensitivity of some older individuals cannot be ruled out. Severe, and sometimes fatal, cases of hepatotoxicity have been reported post-marketing in association with levofloxacin. The majority of fatal hepatotoxicity reports occurred in patients 65 years of age or older and most were not associated with hypersensitivity. Levofloxacin should be discontinued immediately if the patient develops signs and symptoms of hepatitis [see Warnings and Precautions ( 5.8 )]. Elderly patients are at greater risk for aortic aneurysm and dissection. A two-fold increased risk of aortic aneurysm and dissection has been reported following use of a fluoroquinolone, including levofloxacin [see Warnings and Precautions ( 5.9 )]. Elderly patients may be more susceptible to drug-associated effects on the QT interval. Therefore, precaution should be taken when using levofloxacin with concomitant drugs that can result in prolongation of the QT interval (e.g., Class IA or Class III antiarrhythmics) or in patients with risk factors for torsade de pointes (e.g., known QT prolongation, uncorrected hypokalemia) [see Warnings and Precautions ( 5.11 )]. The pharmacokinetic properties of levofloxacin in younger adults and elderly adults do not differ significantly when creatinine clearance is taken into consideration. However, since the drug is known to be substantially excreted by the kidney, 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 Clinical Pharmacology ( 12.3)]. 8.6 Renal Impairment Clearance of levofloxacin is substantially reduced and plasma elimination half-life is substantially prolonged in patients with renal impairment (creatinine clearance < 50 mL/min), requiring dosage adjustment in such patients to avoid accumulation. Neither hemodialysis nor continuous ambulatory peritoneal dialysis (CAPD) is effective in removal of levofloxacin from the body, indicating that supplemental doses of levofloxacin are not required following hemodialysis or CAPD [see Dosage and Administration ( 2.3 )]. 8.7 Hepatic Impairment Pharmacokinetic studies in patients with hepatic impairment have not been conducted. Due to the limited extent of levofloxacin metabolism, the pharmacokinetics of levofloxacin are not expected to be affected by hepatic impairment.

8.4 Pediatric Use Quinolones, including levofloxacin, cause arthropathy and osteochondrosis in juvenile animals of several species. [see Warnings and Precautions ( 5.12 ) and Animal Toxicology and/or Pharmacology ( 13.2 )]. Inhalational Anthrax (Post-Exposure) Levofloxacin is indicated in pediatric patients 6 months of age and older, for inhalational anthrax (post-exposure). The risk-benefit assessment indicates that administration of levofloxacin to pediatric patients is appropriate. The safety of levofloxacin in pediatric patients treated for more than 14 days has not been studied [see Indications and Usage (1.7), Dosage and Administration ( 2.2 ) and Clinical Studies ( 14.9)]. Plague Levofloxacin is indicated in pediatric patients, 6 months of age and older, for treatment of plague, including pneumonic and septicemic plague due to Yersinia pestis (Y. pestis) and prophylaxis for plague. Efficacy studies of levofloxacin could not be conducted in humans with pneumonic plague for ethical and feasibility reasons. Therefore, approval of this indication was based on an efficacy study conducted in animals. The risk-benefit assessment indicates that administration of levofloxacin to pediatric patients is appropriate [see Indications and Usage ( 1.8), Dosage and Administration ( 2.2) and Clinical Studies ( 14.10 )]. Safety and effectiveness of levofloxacin in pediatric patients below the age of six months have not been established. Pharmacokinetics following intravenous administration The pharmacokinetics of levofloxacin following a single intravenous dose were investigated in pediatric patients ranging in age from six months to 16 years. Pediatric patients cleared levofloxacin faster than adult patients resulting in lower plasma exposures than adults for a given mg/kg dose [see Clinical Pharmacology ( 12.3) and Clinical Studies ( 14.9) ]. Dosage in Pediatric Patients with Inhalational Anthrax or Plague For the recommended levofloxacin tablet dosage in pediatric patients with inhalational anthrax or plague, see Dosage and Administration ( 2.2 ). Levofloxacin Tablets cannot be administered to pediatric patients who weigh less than 30 kg because of the limitations of the available strengths. Alternative formulations of levofloxacin may be considered for pediatric patients who weigh less than 30 kg. Adverse Reactions In clinical trials, 1534 pediatric patients (6 months to 16 years of age) were treated with oral and intravenous levofloxacin. Pediatric patients 6 months to 5 years of age received levofloxacin 10 mg/kg twice a day and pediatric patients greater than 5 years of age received 10 mg/kg once a day (maximum 500 mg per day) for approximately 10 days. Levofloxacin tablets can only be administered to pediatric patients with inhalational anthrax (post-exposure) or plague who are 30 kg or greater due to the limitations of the available strengths [see Dosage and Administration ( 2.2)]. A subset of pediatric patients in the clinical trials (1340 levofloxacin-treated and 893 non-fluoroquinolone-treated) enrolled in a prospective, long-term surveillance study to assess the incidence of protocol-defined musculoskeletal disorders (arthralgia, arthritis, tendinopathy, gait abnormality) during 60 days and 1 year following the first dose of the study drug. Pediatric patients treated with levofloxacin had a significantly higher incidence of musculoskeletal disorders when compared to the non-fluoroquinolone-treated children as illustrated in Table 7. Levofloxacin tablets can only be administered to pediatric patients with inhalational anthrax (post-exposure) or plague who are 30 kg or greater due to the limitations of the available strengths [see Dosage and Administration ( 2.2 )]. Table 7: Incidence of Musculoskeletal Disorders in Pediatric Clinical Trial Follow-up Period Levofloxacin N = 1340 Non-Fluoroquinolone * N = 893 p-value † 60 days 28 (2.1%) 8 (0.9%) p = 0.038 1 year ‡ 46 (3.4%) 16 (1.8%) p = 0.025 * Non-Fluoroquinolone: ceftriaxone, amoxicillin/clavulanate, clarithromycin † 2-sided Fisher’s Exact Test ‡ There were 1199 levofloxacin-treated and 804 non-fluoroquinolone-treated pediatric patients who had a one-year evaluation visit. However, the incidence of musculoskeletal disorders was calculated using all reported events during the specified period for all pediatric patients enrolled regardless of whether they completed the 1-year evaluation visit. Arthralgia was the most frequently occurring musculoskeletal disorder in both treatment groups. Most of the musculoskeletal disorders in both groups involved multiple weight-bearing joints. Disorders were moderate in 8/46 (17%) children and mild in 35/46 (76%) levofloxacin-treated pediatric patients and most were treated with analgesics. The median time to resolution was 7 days for levofloxacin-treated pediatric patients and 9 for non-fluoroquinolone-treated children (approximately 80% resolved within 2 months in both groups). No pediatric patient had a severe or serious disorder and all musculoskeletal disorders resolved without sequelae. Vomiting and diarrhea were the most frequently reported adverse reactions, occurring in similar frequency in the levofloxacin-treated and non-fluoroquinolone-treated pediatric patients. In addition to the adverse reactions reported in pediatric patients in clinical trials, adverse reactions reported in adults during clinical trials or post-marketing experience [see Adverse Reactions ( 6)] may also be expected to occur in pediatric patients.