Levofloxacin Injection Concentrate

Name: Levofloxacin Injection Concentrate

Levofloxacin Injection Concentrate Description


Levofloxacin is a synthetic broad-spectrum antibacterial agent for intravenous 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



The molecular formula is C18H20FN3O4 • ½ H2O and the molecular weight is 370.38. Levofloxacin USP is a pale or bright  yellow, 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 is essentially constant (approximately 100 mg/mL). Levofloxacin 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 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.

Excipients and Description of Dosage Forms
 
The appearance of levofloxacin injection may range from a clear yellow to a clear greenish yellow solution. This does not adversely affect product potency.

Levofloxacin Injection in Single-Dose Vials is a sterile, preservative-free aqueous solution of levofloxacin in Water for Injection, with pH ranging from 3.8 to 5.8.

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment of Fertility


In a lifetime bioassay in rats, levofloxacin exhibited no carcinogenic potential following daily dietary administration for 2 years; the highest dose (100 mg/kg/day) was 1.4 times the highest recommended human dose (750 mg) based upon relative body surface area. Levofloxacin did not shorten the time to tumor development of UV-induced skin tumors in hairless albino (Skh-1) mice at any levofloxacin dose level and was therefore not photo-carcinogenic under conditions of this study. Dermal levofloxacin concentrations in the hairless mice ranged from 25 to 42 mcg/g at the highest levofloxacin dose level (300 mg/kg/day) used in the photo-carcinogenicity study. By comparison, dermal levofloxacin concentrations in human subjects receiving 750 mg of levofloxacin averaged approximately 11.8 mcg/g at Cmax.

Levofloxacin was not mutagenic in the following assays: Ames bacterial mutation assay (S. typhimurium and E. coli), CHO/HGPRT forward mutation assay, mouse micronucleus test, mouse dominant lethal test, rat unscheduled DNA synthesis assay, and the mouse sister chromatid exchange assay. It was positive in the in vitro chromosomal aberration (CHL cell line) and sister chromatid exchange (CHL/IU cell line) assays.

Levofloxacin caused no impairment of fertility or reproductive performance in rats at oral doses as high as 360 mg/kg/day, corresponding to 4.2 times the highest recommended human dose based upon relative body surface area and intravenous doses as high as 100 mg/kg/day, corresponding to 1.2 times the highest recommended human dose based upon relative body surface area.

Animal Toxicology and/or Pharmacology


Levofloxacin and other quinolones have been shown to cause arthropathy in immature animals of most species tested [see Warnings and Precautions (5.11)]. In immature dogs (4 to 5 months old), oral doses of 10 mg/kg/day for 7 days and intravenous doses of 4 mg/kg/day for 14 days of levofloxacin resulted in arthropathic lesions. Administration at oral doses of 300 mg/kg/day for 7 days and intravenous doses of 60 mg/kg/day for 4 weeks produced arthropathy in juvenile rats. Three-month old beagle dogs dosed orally with levofloxacin at 40 mg/kg/day exhibited clinically severe arthrotoxicity resulting in the termination of dosing at Day 8 of a 14-day dosing routine. Slight musculoskeletal clinical effects, in the absence of gross pathological or histopathological effects, resulted from the lowest dose level of 2.5 mg/kg/day (approximately 0.2-fold the pediatric dose based upon AUC comparisons). Synovitis and articular cartilage lesions were observed at the 10 and 40 mg/kg dose levels (approximately 0.7-fold and 2.4-fold the pediatric dose, respectively, based on AUC comparisons). Articular cartilage gross pathology and histopathology persisted to the end of the 18-week recovery period for those dogs from the 10 and 40 mg/kg/day dose levels.

When tested in a mouse ear swelling bioassay, levofloxacin exhibited phototoxicity similar in magnitude to ofloxacin, but less phototoxicity than other quinolones.

While crystalluria has been observed in some intravenous rat studies, urinary crystals are not formed in the bladder, being present only after micturition and are not associated with nephrotoxicity.

In mice, the CNS stimulatory effect of quinolones is enhanced by concomitant administration of non-steroidal anti-inflammatory drugs.

In dogs, levofloxacin administered at 6 mg/kg or higher by rapid intravenous injection produced hypotensive effects. These effects were considered to be related to histamine release.

In vitro and in vivo studies in animals indicate that levofloxacin is neither an enzyme inducer nor inhibitor in the human therapeutic plasma concentration range; therefore, no drug metabolizing enzyme-related interactions with other drugs or agents are anticipated.

Clinical Studies

Nosocomial Pneumonia

Adult patients with clinically and radiologically documented nosocomial pneumonia were enrolled in a multicenter, randomized, open-label study comparing intravenous levofloxacin (750 mg once daily) followed by oral levofloxacin (750 mg once daily) for a total of 7 to 15 days to intravenous imipenem/cilastatin (500 to 1000 mg every 6 to 8 hours daily) followed by oral ciprofloxacin (750 mg every 12 hours daily) for a total of 7 to 15 days. Levofloxacin-treated patients received an average of 7 days of intravenous therapy (range: 1 to 16 days); comparator-treated patients received an average of 8 days of intravenous therapy (range: 1 to 19 days).

Overall, in the clinically and microbiologically evaluable population, adjunctive therapy was empirically initiated at study entry in 56 of 93 (60.2%) patients in the levofloxacin arm and 53 of 94 (56.4%) patients in the comparator arm. The average duration of adjunctive therapy was 7 days in the levofloxacin arm and 7 days in the comparator. In clinically and microbiologically evaluable patients with documented Pseudomonas aeruginosa infection, 15 of 17 (88.2%) received ceftazidime (N = 11) or piperacillin/tazobactam (N = 4) in the levofloxacin arm and 16 of 17 (94.1%) received an aminoglycoside in the comparator arm. Overall, in clinically and microbiologically evaluable patients, vancomycin was added to the treatment regimen of 37 of 93 (39.8%) patients in the levofloxacin arm and 28 of 94 (29.8%) patients in the comparator arm for suspected methicillin-resistant S. aureus infection.

Clinical success rates in clinically and microbiologically evaluable patients at the posttherapy visit (primary study endpoint assessed on day 3 to 15 after completing therapy) were 58.1% for levofloxacin and 60.6% for comparator. The 95% CI for the difference of response rates (levofloxacin minus comparator) was [-17.2, 12.0]. The microbiological eradication rates at the posttherapy visit were 66.7% for levofloxacin and 60.6% for comparator. The 95% CI for the difference of eradication rates (levofloxacin minus comparator) was [-8.3, 20.3]. Clinical success and microbiological eradication rates by pathogen are detailed in Table 13.

                                    Table 13: Clinical Success Rates and Bacteriological Eradication Rates (Nosocomial Pneumonia)

Pathogen
     N   
Levofloxacin No. (%) of Patients Microbiologic/ Clinical Outcomes
   N     
Imipenem/Cilastatin No. (%) of Patients Microbiologic/ Clinical Outcomes
MSSA*
    21   
14 (66.7)/13 (61.9)
    19   
13 (68.4)/15 (78.9)
P. aeruginosa†
   17      
10 (58.8)/11 (64.7)
    17   
5 (29.4)/7 (41.2)
S. marcescens
    11   
9 (81.8)/7 (63.6)
   7   
2 (28.6)/3 (42.9)
E. coli
    12   
10 (83.3)/7 (58.3)
    11   
7 (63.6)/8 (72.7)
K. pneumoniae‡
    11  
9 (81.8)/5 (45.5)
7   
6 (85.7)/3 (42.9)
H. influenzae
    16   
13 (81.3)/10 (62.5)
    15   
14 (93.3)/11 (73.3)
S. pneumoniae
    4   
3 (75.0)/3 (75.0)
    7    
5 (71.4)/4 (57.1)

*  Methicillin-susceptible S. aureus

†  See above text for use of combination therapy

‡  The observed differences in rates for the clinical and microbiological outcomes may reflect other factors that were not accounted for in the study

Community-Acquired Pneumonia: 7 to 14 day Treatment Regimen

Adult inpatients and outpatients with a diagnosis of community-acquired bacterial pneumonia were evaluated in 2 pivotal clinical studies. In the first study, 590 patients were enrolled in a prospective, multi-center, unblinded randomized trial comparing levofloxacin 500 mg once daily orally or intravenously for 7 to 14 days to ceftriaxone 1 to 2 grams intravenously once or in equally divided doses twice daily followed by cefuroxime axetil  500 mg orally twice daily for a total of 7 to 14 days. Patients assigned to treatment with the control regimen were allowed to receive erythromycin (or doxycycline if intolerant of erythromycin) if an infection due to atypical pathogens was suspected or proven. Clinical and microbiologic evaluations were performed during treatment, 5 to 7 days posttherapy, and 3 to 4 weeks posttherapy. Clinical success (cure plus improvement) with levofloxacin at 5 to 7 days posttherapy, the primary efficacy variable in this study, was superior (95%) to the control group (83%). The 95% CI for the difference of response rates (levofloxacin  minus comparator) was [-6, 19]. In the second study, 264 patients were enrolled in a prospective, multi-center, non-comparative trial of 500 mg levofloxacin administered orally or intravenously once daily for 7 to 14 days. Clinical success for clinically evaluable patients was 93%. For both studies, the clinical success rate in patients with atypical pneumonia due to Chlamydophila pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila were 96%, 96%, and 70%, respectively. Microbiologic eradication rates across both studies are presented in Table 14.

                      Table 14: Bacteriological Eradication Rates Across 2 Community Acquired Pneumonia Clinical Studies

  Pathogen
No. Pathogens
Bacteriological Eradication Rate (%)
  H. influenzae
55
98
  S. pneumoniae
83
95
  S. aureus
17
88
  M. catarrhalis
18
94
  H. parainfluenzae
19
95
  K. pneumoniae
10
100.0

Community-Acquired Pneumonia Due to Multi-Drug Resistant Streptococcus pneumoniae

Levofloxacin was effective for the treatment of community-acquired pneumonia caused by multi-drug resistant Streptococcus pneumoniae (MDRSP). 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). Of 40 microbiologically evaluable patients with MDRSP isolates, 38 patients (95.0%) achieved clinical and bacteriologic success at post-therapy. The clinical and bacterial success rates are shown in Table 15.

Table 15:  Clinical and Bacterial Success Rates for Levofloxacin-Treated MDRSP in Community Acquired Pneumonia Patients (Population Valid for Efficacy)

* One patient had a respiratory isolate that was resistant to tetracycline, cefuroxime, macrolides and TMP/SMX and intermediate to penicillin and a blood isolate that was intermediate to penicillin and cefuroxime and resistant to the other classes. The patient is included in the database based on   respiratory isolate.
† n = the number of microbiologically evaluable patients who were clinical successes; N = number of   microbiologically evaluable patients in the designated resistance group.
‡ n = the number of MDRSP isolates eradicated or presumed eradicated in microbiologically evaluable  patients; N = number of MDRSP isolates in a designated resistance group.
 Screening Susceptibility
Clinical Success
Bacteriological Success*
n/N†
%
n/N‡
%
  Penicillin-resistant
16/17
94.1
16/17
94.1
  2nd generation Cephalosporin resistant
31/32
96.9
31/32
96.9
  Macrolide-resistant
28/29
96.6
28/29
96.6
  Trimethoprim/Sulfamethoxazole resistant
17/19
89.5
17/19
89.5
  Tetracycline-resistant
12/12
100
12/12
100

Not all isolates were resistant to all antimicrobial classes tested. Success and eradication rates are summarized in Table 16.

Table 16: Clinical Success and Bacteriologic Eradication Rates for Resistant Streptococcus pneumoniae (Community Acquired Pneumonia)

  Type of Resistance
Clinical Success
Bacteriologic Eradication
  Resistant to 2 antibacterials
17/18 (94.4%)
17/18 (94.4%)
  Resistant to 3 antibacterials
14/15 (93.3%)
14/15 (93.3%)
  Resistant to 4 antibacterials
7/7 (100%)
7/7 (100%)
  Resistant to 5 antibacterials
0
0
  Bacteremia with MDRSP 
8/9 (89%)
8/9 (89%)

Community-Acquired Pneumonia: 5-day Treatment Regimen

To evaluate the safety and efficacy of the higher dose and shorter course of levofloxacin, 528 outpatient and hospitalized adults with clinically and radiologically determined mild to severe community-acquired pneumonia were evaluated in a double-blind, randomized, prospective, multicenter study comparing levofloxacin 750 mg, IV or orally, every day for five days or levofloxacin 500 mg IV or orally, every day for 10 days.

Clinical success rates (cure plus improvement) in the clinically evaluable population were 90.9% in the levofloxacin 750 mg group and 91.1% in the levofloxacin 500 mg group. The 95% CI for the difference of response rates (levofloxacin 750 minus levofloxacin 500) was [-5.9, 5.4]. In the clinically evaluable population (31 to 38 days after enrollment) pneumonia was observed in 7 out of 151 patients in the levofloxacin 750 mg group and 2 out of 147 patients in the levofloxacin 500 mg group. Given the small numbers observed, the significance of this finding cannot be determined statistically. The microbiological efficacy of the 5-day regimen was documented for infections listed in Table 17.

                                          Table 17: Bacteriological Eradication Rates (Community-Acquired Pneumonia)

   S. pneumoniae
19/20 (95%)
  Haemophilus influenzae
12/12 (100%)
  Haemophilus parainfluenzae
10/10 (100%)
  Mycoplasma pneumoniae
26/27 (96%)
  Chlamydophila pneumoniae
13/15 (87%)

Acute Bacterial Sinusitis: 5-day and 10 to 14 day Treatment Regimens

Levofloxacin is approved for the treatment of acute bacterial sinusitis (ABS) using either 750 mg by mouth x 5 days or 500 mg by mouth once daily x 10 to 14 days. To evaluate the safety and efficacy of a high dose short course of levofloxacin, 780 outpatient adults with clinically and radiologically determined acute bacterial sinusitis were evaluated in a double-blind, randomized, prospective, multicenter study comparing levofloxacin 750 mg by mouth once daily for five days to levofloxacin 500 mg by mouth once daily for 10 days.

Clinical success rates (defined as complete or partial resolution of the pre-treatment signs and symptoms of ABS to such an extent that no further antibiotic treatment was deemed necessary) in the microbiologically evaluable population were 91.4% (139/152) in the levofloxacin 750 mg group and 88.6% (132/149) in the levofloxacin 500 mg group at the test-of-cure (TOC) visit (95% CI [-4.2, 10.0] for levofloxacin 750 mg minus levofloxacin 500 mg).

Rates of clinical success by pathogen in the microbiologically evaluable population who had specimens obtained by antral tap at study entry showed comparable results for the five- and ten-day regimens at the test-of-cure visit 22 days post treatment (see Table 18).


Table 18: Clinical Success Rate by Pathogen at the TOC in Microbiologically Evaluable Subjects Who Underwent Antral Puncture (Acute Bacterial Sinusitis)
Pathogen Levofloxacin 750 mg x 5 days Levofloxacin 500 mg x 10 days
* Note: Forty percent of the subjects in this trial had specimens obtained by sinus endoscopy. The efficacy data for subjects whose specimen was obtained endoscopically were comparable to those presented in the above table.
   Streptococcus pneumoniae*
25/27 (92.6%)
26/27 (96.3%)
   Haemophilus influenzae*
19/21 (90.5%)
25/27 (92.6%)
   Moraxella catarrhalis*
10/11 (90.9%)
13/13 (100%)

Complicated Skin and Skin Structure Infections


Three hundred ninety-nine patients were enrolled in an open-label, randomized, comparative study for complicated skin and skin structure infections. The patients were randomized to receive either levofloxacin 750 mg once daily (IV followed by oral), or an approved comparator for a median of 10 ± 4.7 days. As is expected in complicated skin and skin structure infections, surgical procedures were performed in the levofloxacin and comparator groups. Surgery (incision and drainage or debridement) was performed on 45% of the levofloxacin-treated patients and 44% of the comparator-treated patients, either shortly before or during antibiotic treatment and formed an integral part of therapy for this indication.

Among those who could be evaluated clinically 2 to 5 days after completion of study drug, overall success rates (improved or cured) were 116/138 (84.1%) for patients treated with levofloxacin and 106/132 (80.3%) for patients treated with the comparator.

Success rates varied with the type of diagnosis ranging from 68% in patients with infected ulcers to 90% in patients with infected wounds and abscesses. These rates were equivalent to those seen with comparator drugs.

Chronic Bacterial Prostatitis

Adult patients with a clinical diagnosis of prostatitis and microbiological culture results from urine sample collected after prostatic massage (VB3) or expressed prostatic secretion (EPS) specimens obtained via the Meares-Stamey procedure were enrolled in a multicenter, randomized, double-blind study comparing oral levofloxacin 500 mg, once daily for a total of 28 days to oral ciprofloxacin 500 mg, twice daily for a total of 28 days. The primary efficacy endpoint was microbiologic efficacy in microbiologically evaluable patients. A total of 136 and 125 microbiologically evaluable patients were enrolled in the levofloxacin and ciprofloxacin groups, respectively. The microbiologic eradication rate by patient infection at 5 to 18 days after completion of therapy was 75.0% in the levofloxacin group and 76.8% in the ciprofloxacin group (95% CI [-12.58, 8.98] for levofloxacin minus ciprofloxacin). The overall eradication rates for pathogens of interest are presented in Table 19.

                                              Table 19: Bacteriological Eradication Rates (Chronic Bacterial Prostatitis)

* Eradication rates shown are for patients who had a sole pathogen only; mixed cultures were excluded.
  Pathogen
Levofloxacin  (N = 136)
Ciprofloxacin (N = 125)
N
Eradication
N
Eradication
  E. coli
15
14 (93.3%)
11
9 (81.8%)
  E. faecalis
54
39 (72.2%)
44
33 (75.0%)
  S. epidermidis*
11
9 (81.8%)
14
11 (78.6%)

Eradication rates for S. epidermidis when found with other co-pathogens are consistent with rates seen in pure isolates.

Clinical success (cure + improvement with no need for further antibiotic therapy) rates in microbiologically evaluable population 5 to 18 days after completion of therapy were 75.0% for levofloxacin-treated patients and 72.8% for ciprofloxacin-treated patients (95% CI [-8.87, 13.27] for levofloxacin minus ciprofloxacin). Clinical long-term success (24 to 45 days after completion of therapy) rates were 66.7% for the levofloxacin-treated patients and 76.9% for the ciprofloxacin-treated patients (95% CI [-23.40, 2.89] for levofloxacin minus ciprofloxacin).

Complicated Urinary Tract Infections and Acute Pyelonephritis: 5-day Treatment Regimen


To evaluate the safety and efficacy of the higher dose and shorter course of levofloxacin, 1109 patients with cUTI and AP were enrolled in a randomized, double-blind, multicenter clinical trial conducted in the U.S. from November 2004 to April 2006 comparing levofloxacin 750 mg IV or orally once daily for 5 days (546 patients) with ciprofloxacin 400 mg IV or 500 mg orally twice daily for 10 days (563 patients). Patients with AP complicated by underlying renal diseases or conditions such as complete obstruction, surgery, transplantation, concurrent infection or congenital malformation were excluded. Efficacy was measured by bacteriologic eradication of the baseline organism(s) at the post-therapy visit in patients with a pathogen identified at baseline. The post-therapy (test-of-cure) visit occurred 10 to 14 days after the last active dose of levofloxacin and 5 to 9 days after the last dose of active ciprofloxacin.

The bacteriologic cure rates overall for levofloxacin and control at the test-of-cure (TOC) visit for the group of all patients with a documented pathogen at baseline (modified intent to treat or mITT) and the group of patients in the mITT population who closely followed the protocol (Microbiologically Evaluable) are summarized in Table 20.


Table 20: Bacteriological Eradication at Test-of-Cure
Levofloxacin
750 mg orally or
IV once daily
for 5 days
Ciprofloxacin
400 mg IV/500 mg
orally twice daily
for 10 days
Overall Difference
[95% CI]
n/N % n/N % Levofloxacin-
Ciprofloxacin
*The mITT population included patients who received study medication and who had a positive (≥105 CFU/mL) urine culture with no more than 2 uropathogens at baseline. Patients with missing response were counted as failures in this analysis.
†The Microbiologically Evaluable population included patients with a confirmed diagnosis of cUTI or AP, a causative organism(s) at baseline present at ≥105 CFU/mL, a valid test-of-cure urine culture, no pathogen isolated from blood resistant to study drug, no premature discontinuation or loss to follow-up, and compliance with treatment (among other criteria).
mITT Population*
   Overall (cUTI or AP)
252/333
75.7
239/318
75.2
0.5 (-6.1, 7.1)
   cUTI
168/230
73.0
157/213
73.7
 
   AP
84/103
81.6
82/105
78.1
 
Microbiologically Evaluable Population†
   Overall (cUTI or AP)
228/265
86.0
215/241
89.2
-3.2 [-8.9, 2.5]
   cUTI
154/185
83.2
144/165
87.3
 
   AP
74/80
92.5
71/76
93.4
 

Microbiologic eradication rates in the Microbiologically Evaluable population at TOC for individual pathogens recovered from patients randomized to levofloxacin treatment are presented in Table 21.


Table 21: Bacteriological Eradication Rates for Individual Pathogens Recovered From Patients Randomized to Levofloxacin 750 mg QD for 5 Days Treatment
Pathogen Bacteriological
Eradication Rate (n/N)
%
* The predominant organism isolated from patients with AP was E. coli: 91% (63/69) eradication in AP and 89% (92/103) in patients with cUTI.
   Escherichia coli*
155/172
90
   Klebsiella pneumoniae
20/23
87
   Proteus mirabilis
12/12
100

Complicated Urinary Tract Infections and Acute Pyelonephritis: 10-day Treatment Regimen


To evaluate the safety and efficacy of the 250 mg dose, 10 day regimen of levofloxacin, 567 patients with uncomplicated UTI, mild-to-moderate cUTI, and mild-to-moderate AP were enrolled in a randomized, double-blind, multicenter clinical trial conducted in the U.S. from June 1993 to January 1995 comparing levofloxacin 250 mg orally once daily for 10 days (285 patients) with ciprofloxacin 500 mg orally twice daily for 10 days (282 patients). Patients with a resistant pathogen, recurrent UTI, women over age 55 years, and with an indwelling catheter were initially excluded, prior to protocol amendment which took place after 30% of enrollment. Microbiological efficacy was measured by bacteriologic eradication of the baseline organism(s) at 1 to 12 days post-therapy in patients with a pathogen identified at baseline.

The bacteriologic cure rates overall for levofloxacin and control at the test-of-cure (TOC) visit for the group of all patients with a documented pathogen at baseline (modified intent to treat or mITT) and the group of patients in the mITT population who closely followed the protocol (Microbiologically Evaluable) are summarized in Table 22.


Table 22: Bacteriological Eradication Overall (cUTI or AP) at Test-Of-Cure*
Levofloxacin
250 mg once daily
for 10 days
Ciprofloxacin
500 mg twice daily
for 10 days
n/N % n/N %
*1 to 9 days posttherapy for 30% of subjects enrolled prior to a protocol amendment; 5 to 12 days posttherapy for 70% of subjects.
†The mITT population included patients who had a pathogen isolated at baseline. Patients with missing response were counted as failures in this analysis.
‡ The Microbiologically Evaluable population included mITT patients who met protocol-specified evaluability criteria.
   mITT Population†
174/209
83.3
184/219
84.0
   Microbiologically Evaluable Population‡
164/177
92.7
159/171
93.0

Inhalational Anthrax (Post-Exposure)


The effectiveness of levofloxacin for this indication is based on plasma concentrations achieved in humans, a surrogate endpoint reasonably likely to predict clinical benefit. Levofloxacin has not been tested in humans for the post-exposure prevention of inhalation anthrax. The mean plasma concentrations of levofloxacin associated with a statistically significant improvement in survival over placebo in the rhesus monkey model of inhalational anthrax are reached or exceeded in adult and pediatric patients receiving the recommended oral and intravenous dosage regimens [see Indications and Usage (1.7); Dosage and Administration (2.1, 2.2)].
 
Levofloxacin pharmacokinetics have been evaluated in adult and pediatric patients. The mean (± SD) steady state peak plasma concentration in human adults receiving 500 mg orally or intravenously once daily is 5.7 ± 1.4 and 6.4 ± 0.8 mcg/mL, respectively; and the corresponding total plasma exposure (AUC0-24) is 47.5 ± 6.7 and  54.6 ± 11.1 mcg•h/mL, respectively. The predicted steady-state pharmacokinetic parameters in pediatric patients ranging in age from 6 months to 17 years receiving 8 mg/kg orally every 12 hours (not to exceed 250 mg per dose) were calculated to be comparable to those observed in adults receiving 500 mg orally once daily [see Clinical Pharmacology (12.3)].

In adults, the safety of levofloxacin for treatment durations of up to 28 days is well characterized. However, information pertaining to extended use at 500 mg daily up to 60 days is limited. Prolonged levofloxacin therapy in adults should only be used when the benefit outweighs the risk.

In pediatric patients, the safety of levofloxacin for treatment durations of more than 14 days has not been studied. An increased incidence of musculoskeletal adverse events (arthralgia, arthritis, tendinopathy, gait abnormality) compared to controls has been observed in clinical studies with treatment duration of up to 14 days. Long-term safety data, including effects on cartilage, following the administration of levofloxacin to pediatric patients is limited [see Warnings and Precautions (5.10), Use in Specific Populations (8.4)].

A placebo-controlled animal study in rhesus monkeys exposed to an inhaled mean dose of 49 LD50 (~2.7 x 106) spores (range 17 to 118 LD50) of B. anthracis (Ames strain) was conducted. The minimal inhibitory concentration (MIC) of levofloxacin for the anthrax strain used in this study was 0.125 mcg/mL. In the animals studied, mean plasma concentrations of levofloxacin achieved at expected Tmax (1 hour post-dose) following oral dosing to steady state ranged from 2.79 to 4.87 mcg/mL. Steady state trough concentrations at 24 hours post-dose ranged from 0.107 to 0.164 mcg/mL. Mean (SD) steady state AUC0-24 was 33.4 ± 3.2 mcg•h/mL (range 30.4 to 36.0 mcg•h/mL). Mortality due to anthrax for animals that received a 30 day regimen of oral levofloxacin beginning 24 hrs post exposure was significantly lower (1/10), compared to the placebo group (9/10) [P = 0.0011, 2-sided Fisher’s Exact Test]. The one levofloxacin treated animal that died of anthrax did so following the 30-day drug administration period.

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 mean plasma concentrations of levofloxacin associated with a statistically significant improvement in survival over placebo in an African green monkey model of pneumonic plague are reached or exceeded in adult and pediatric patients receiving the recommended oral and intravenous dosage regimens [see Indications and Usage (1.8), Dosage and Administration (2.1), (2.2)].

Levofloxacin pharmacokinetics have been evaluated in adult and pediatric patients. The mean (± SD) steady state peak plasma concentration in human adults receiving 500 mg orally or intravenously once daily is 5.7 ± 1.4 and 6.4 ± 0.8 mcg/mL, respectively; and the corresponding total plasma exposure (AUC0-24) is 47.5 ± 6.7 and 54.6 ± 11.1 mcg•h/mL, respectively. The predicted steady-state pharmacokinetic parameters in pediatric patients ranging in age from 6 months to 17 years receiving 8 mg/kg orally every 12 hours (not to exceed 250 mg per dose) were calculated to be comparable to those observed in adults receiving 500 mg orally once daily [see Clinical Pharmacology (12.3)].

A placebo-controlled animal study in African green monkeys exposed to an inhaled mean dose of 65 LD50 (range 3 to 145 LD50) of Yersinia pestis (CO92 strain) was conducted. The minimal inhibitory concentration (MIC) of levofloxacin for the Y. pestis strain used in this study was 0.03 mcg/mL. Mean plasma concentrations of levofloxacin achieved at the end of a single 30-min infusion ranged from 2.84 to 3.50 mcg/mL in African green monkeys. Trough concentrations at 24 hours post-dose ranged from <0.03 to 0.06 mcg/mL. Mean (SD) AUC0-24 was 11.9 (3.1) mcg•h/mL (range 9.50 to 16.86 mcg•h/mL). Animals were randomized to receive either a 10-day regimen of i.v. levofloxacin or placebo beginning within 6 hrs of the onset of telemetered fever (≥ 39ºC for more than 1 hour). Mortality in the levofloxacin group was significantly lower (1/17) compared to the placebo group (7/7) [p<0.001, Fisher’s Exact Test; exact 95% confidence interval (-99.9%, -55.5%) for the difference in mortality]. One levofloxacin-treated animal was euthanized on Day 9 post-exposure to Y. pestis due to a gastric complication; it had a blood culture positive for Y. pestis on Day 3 and all subsequent daily blood cultures from Day 4 through Day 7 were negative.

How Supplied/Storage and Handling

Levofloxacin Injection, Single-Dose Vials


Levofloxacin injection is supplied in single-dose vials. Each vial contains a clear yellow to a clear greenish yellow concentrated solution with the equivalent of 500 mg of levofloxacin in 20 mL vials and 750 mg of levofloxacin in 30 mL vials.



  • 500 mg (25 mg/mL), 20 mL vials in a carton of 1               NDC 55150-156-20
  • 750 mg (25 mg/mL), 30 mL vials in a carton of 1               NDC 55150-157-30  

  
Levofloxacin injection in single-dose vials should be stored at 20° - 25°C (68° - 77°F) [See USP Controlled Room Temperature].

Retain in Carton until time of use.

Keep out of reach of children. 

Medication guide

Levofloxacin (lee voe FLOX a sin)
Injection
for Intravenous Use

Read this Medication Guide before you start taking levofloxacin and each time you get a refill. There may be new information. This Medication Guide does not take the place of talking to your healthcare provider about your medical condition or your treatment.

What is the most important information I should know about levofloxacin?

Levofloxacin, a fluoroquinolone antibiotic, can cause serious side effects. Some of these serious side effects can happen at the same time and could result in death.

If you have any of the following serious side effects while you take levofloxacin, you should stop taking levofloxacin immediately and get medical help right away.

1. Tendon rupture or swelling of the tendon (tendinitis).

  • Tendon problems can happen in people of all ages who take levofloxacin. Tendons are tough cords of tissue that connect muscles to bones.

Some tendon problems include pain, swelling, tears, and swelling of tendons including the back of the ankle (Achilles), shoulder, hand, or other tendon sites.


  • The risk of getting tendon problems while you take levofloxacin is higher if you:
    • are over 60 years of age
    • are taking steroids (corticosteroids)
    • have had a kidney, heart or lung transplant.
  • Tendon problems can happen in people who do not have the above risk factors when they take levofloxacin.
  • Other reasons that can increase your risk of tendon problems can include:
    • physical activity or exercise
    • kidney failure
    • tendon problems in the past, such as in people with rheumatoid arthritis (RA)
  • Stop taking levofloxacin immediately and get medical help right away at the first sign of tendon pain, swelling or inflammation. Avoid exercise and using the affected area.

The most common area of pain and swelling is the Achilles tendon at the back of your ankle. This can also happen with other tendons. You may need a different antibiotic that is not a fluoroquinolone to treat your infection.


  • Tendon rupture can happen while you are taking or after you have finished taking levofloxacin. Tendon ruptures can happen within hours or days of taking levofloxacin and have happened up to several months after people have finished taking their fluoroquinolone.
  • Stop taking levofloxacin immediately and get medical help right away if you get any of the following signs or symptoms of a tendon rupture:
    • hear or feel a snap or pop in a tendon area
    • bruising right after an injury in a tendon area
    • unable to move the affected area or bear weight

2. Changes in sensation and possible nerve damage (Peripheral Neuropathy). Damage to the nerves in arms, hands, legs, or feet can happen in people who take fluoroquinolones, including levofloxacin. Stop taking levofloxacin immediately and talk to your healthcare provider right away if you get any of the following symptoms of peripheral neuropathy in your arms, hands, legs, or feet:


  • pain
  • burning
  • tingling
  • numbness
  • weakness

The nerve damage may be permanent.

3. Central Nervous System (CNS) effects. Seizures have been reported in people who take fluoroquinolone antibacterial medicines, including levofloxacin. Tell your healthcare provider if you have a history of seizures before you start taking levofloxacin. CNS side effects may happen as soon as after taking the first dose of levofloxacin. Stop taking levofloxacin immediately and talk to your healthcare provider right away if you get any of these side effects, or other changes in mood or behavior:

  • seizures
  • hear voices, see things, or sense things that are not there (hallucinations)
  • feel restless
  • tremors
  • feel anxious or nervous
  • confusion
  • depression
  • trouble sleeping
  • nightmares
  • feel lightheaded or dizzy
  • feel more suspicious (paranoia)
  • suicidal thoughts or acts
  • headaches that will not go away, with or without blurred vision

4. Worsening of myasthenia gravis (a problem that causes muscle weakness). Fluoroquinolones like levofloxacin may cause worsening of myasthenia gravis symptoms, including muscle weakness and breathing problems. Tell your healthcare provider if you have a history of myasthenia gravis before you start taking levofloxacin. Call your healthcare provider right away if you have any worsening muscle weakness or breathing problems.

What is levofloxacin?

Levofloxacin is a fluoroquinolone antibiotic medicine used in adults age 18 years or older to treat certain infections caused by certain germs called bacteria. These bacterial infections include:


  • nosocomial pneumonia
  • community acquired pneumonia
  • acute sinus infection
  • acute worsening of chronic bronchitis
  • skin infections, complicated and uncomplicated
  • chronic prostate infection
  • urinary tract infections, complicated and uncomplicated
  • acute kidney infection (pyelonephritis)
  • inhalation anthrax
  • plague

Studies of levofloxacin for use in the treatment of plague and anthrax were done in animals only, because plague and anthrax could not be studied in people.

Levofloxacin should not be used in patients with uncomplicated urinary tract infections, acute bacterial exacerbation of chronic bronchitis, or acute bacterial sinusitis if there are other treatment options available.

Levofloxacin is also used to treat children who are 6 months of age or older and may have breathed in anthrax germs, have plague, or been exposed to plague germs.

It is not known if levofloxacin is safe and effective in children under 6 months of age.

The safety and effectiveness in children treated with levofloxacin for more than 14 days is not known.

Who should not take levofloxacin?

Do not take levofloxacin if you have ever had a severe allergic reaction to an antibiotic known as a fluoroquinolone, or if you are allergic to levofloxacin or any of the ingredients in levofloxacin injection. See the end of this leaflet for a complete list of ingredients in levofloxacin injection.

What should I tell my healthcare provider before taking levofloxacin?

Before you take levofloxacin, tell your healthcare provider if you:

  • have tendon problems; levofloxacin should not be used in patients who have a history of tendon problems
  • have a problem that causes muscle weakness (myasthenia gravis); levofloxacin should not be used in patients who have a known history of myasthenia gravis
  • have central nervous system problems such as seizures (epilepsy)
  • have nerve problems; levofloxacin should not be used in patients who have a history of a nerve problem called peripheral neuropathy
  • have or anyone in your family has an irregular heartbeat, especially a condition called “QT prolongation”
  • have low blood potassium (hypokalemia)
  • have bone problems
  • have joint problems including rheumatoid arthritis (RA)

  • have kidney problems. You may need a lower dose of levofloxacin if your kidneys do not work well.
  • have liver problems
  • have diabetes or problems with low blood sugar (hypoglycemia)

  • are pregnant or plan to become pregnant. It is not known if levofloxacin will harm your unborn child.

  • are breastfeeding or plan to breastfeed. It is not known if levofloxacin passes into your breast milk. You and your healthcare provider should decide if you will take levofloxacin or breastfeed. You should not do both.

Tell your healthcare provider about all the medicines you take, including prescription and non-prescription medicines, vitamins, and herbal supplements.

Levofloxacin and other medicines can affect each other causing side effects.

Especially tell your healthcare provider if you take:


  • a steroid medicine.
  • an anti-psychotic medicine
  • a tricyclic antidepressant
  • a water pill (diuretic)
  • a blood thinner (warfarin, Coumadin, Jantoven)
  • an oral anti-diabetes medicine or insulin
  • an NSAID (Non-Steroidal Anti-Inflammatory Drug). Many common medicines for pain relief are NSAIDs. Taking an NSAID while you take levofloxacin or other fluoroquinolones may increase your risk of central nervous system effects and seizures.
  • theophylline (Theo-24®, Elixophyllin®, Theochron®, Uniphyl®, Theolair®)
  • a medicine to control your heart rate or rhythm (antiarrhythmics)  

Ask your healthcare provider if you are not sure if any of your medicines are listed above.

Know the medicines you take. Keep a list of your medicines and show it to your healthcare provider and pharmacist when you get a new medicine.

How should I take levofloxacin?


  • Take levofloxacin exactly as your healthcare provider tells you to take it.
  • Take levofloxacin at about the same time each day.
  • Drink plenty of fluids while you take levofloxacin.
  • If you miss a dose of levofloxacin, take it as soon as you remember. Do not take more than 1 dose in 1 day.
  • Levofloxacin Injection is given by slow intravenous (I.V.) infusion into your vein over 60 or 90 minutes as prescribed by your healthcare provider.
  • Do not skip any doses of levofloxacin or stop taking it, even if you begin to feel better, until you finish your prescribed treatment, unless:
    • you have tendon problems. See “What is the most important information I should know about levofloxacin?”.
    • you have a nerve problem. See “What are the possible side effects of levofloxacin?”.
    • you have a central nervous system problem. See “What are the possible side effects of levofloxacin?”.
    • you have a serious allergic reaction. See “What are the possible side effects of levofloxacin?”.
    • your healthcare provider tells you to stop taking levofloxacin

Taking all of your levofloxacin doses will help make sure that all of the bacteria are killed. Taking all of your levofloxacin doses will help you lower the chance that the bacteria will become resistant to levofloxacin. If your infection does not get better while you take levofloxacin, it may mean that the bacteria causing your infection may be resistant to levofloxacin. If your infection does not get better, call your healthcare provider. If your infection does not get better, levofloxacin and other similar antibiotic medicines may not work for you in the future.


  • If you take too much levofloxacin, call your healthcare provider or get medical help right away.

What should I avoid while taking levofloxacin?


  • Levofloxacin can make you feel dizzy and lightheaded. Do not drive, operate machinery, or do other activities that require mental alertness or coordination until you know how levofloxacin affects you.
  • Avoid sunlamps, tanning beds, and try to limit your time in the sun. Levofloxacin can make your skin sensitive to the sun (photosensitivity) and the light from sunlamps and tanning beds. You could get severe sunburn, blisters or swelling of your skin. If you get any of these symptoms while you take levofloxacin, call your healthcare provider right away. You should use a sunscreen and wear a hat and clothes that cover your skin if you have to be in sunlight.

What are the possible side effects of levofloxacin?

Levofloxacin can cause serious side effects, including:

  • See “What is the most important information I should know about levofloxacin?”
  • Serious allergic reactions.

Allergic reactions can happen in people taking fluoroquinolones, including levofloxacin, even after only 1 dose. Stop taking levofloxacin and get emergency medical help right away if you have any of the following symptoms of a severe allergic reaction:

  • hives
  • trouble breathing or swallowing
  • swelling of the lips, tongue, face
  • throat tightness, hoarseness
  • rapid heartbeat
  • faint
  • skin rash

Skin rash may happen in people taking levofloxacin, even after only 1 dose. Stop taking levofloxacin at the first sign of a skin rash and immediately call your healthcare provider. Skin rash may be a sign of a more serious reaction to levofloxacin.


  • Liver damage (hepatotoxicity): Hepatotoxicity can happen in people who take levofloxacin. Call your healthcare provider right away if you have unexplained symptoms such as:
    • nausea or vomiting
    • stomach pain
    • fever
    • weakness
    • abdominal pain or tenderness
    • itching
    • unusual tiredness
    • loss of appetite
    • light colored bowel movements
    • dark colored urine
    • yellowing of your skin or the whites of your eyes

Stop taking levofloxacin and tell your healthcare provider right away if you have yellowing of your skin or white part of your eyes, or if you have dark urine. These can be signs of a serious reaction to levofloxacin (a liver problem).



  • Intestine infection (Pseudomembranous colitis)

Pseudomembranous colitis can happen with many antibiotics, including levofloxacin. Call your healthcare provider right away if you get watery diarrhea, diarrhea that does not go away, or bloody stools. You may have stomach cramps and a fever. Pseudomembranous colitis can happen 2 or more months after you have finished your antibiotic.

  • Serious heart rhythm changes (QT prolongation and torsades de pointes)

Tell your healthcare provider right away if you have a change in your heart beat (a fast or irregular heartbeat), or if you faint. Levofloxacin may cause a rare heart problem known as prolongation of the QT interval. This condition can cause an abnormal heartbeat and can be very dangerous. The chances of this happening are higher in people:

  • who are elderly
  • with a family history of prolonged QT interval
  • with low blood potassium (hypokalemia)
  • who take certain medicines to control heart rhythm (antiarrhythmics)

  • Joint Problems

Increased chance of problems with joints and tissues around joints in children can happen. Tell your child’s healthcare provider if your child has any joint problems during or after treatment with levofloxacin.

  • Changes in blood sugar

People who take levofloxacin and other fluoroquinolone medicines with oral anti-diabetes medicines or with insulin can get low blood sugar (hypoglycemia) and high blood sugar (hyperglycemia). Follow your healthcare provider’s instructions for how often to check your blood sugar. If you have diabetes and you get low blood sugar while taking levofloxacin, stop taking levofloxacin and call your healthcare provider right away. Your antibiotic medicine may need to be changed.

  • Sensitivity to sunlight (photosensitivity)

See “What should I avoid while taking levofloxacin?”


The most common side effects of levofloxacin include:


  • nausea
  • headache
  • diarrhea
  • insomnia
  • constipation
  • dizziness

In children 6 months and older who take levofloxacin to treat anthrax disease or plague, vomiting is also common.

Low blood pressure can happen when levofloxacin is given too fast by IV injection. Tell your healthcare provider if you feel dizzy or faint during a treatment with levofloxacin injection.

Levofloxacin may cause false-positive urine screening results for opiates when testing is done with some commercially available kits. A positive result should be confirmed using a more specific test.

These are not all the possible side effects of levofloxacin. Tell your healthcare provider about any side effect that bothers you or that does not go away.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

How should I store levofloxacin?

Levofloxacin injection should be stored at 20° - 25°C (68° - 77°F) [See USP Controlled Room Temperature].

Keep levofloxacin and all medicines out of the reach of children.

General information about the safe and effective use of levofloxacin

Medicines are sometimes prescribed for purposes other than those listed in a Medication Guide. Do not use levofloxacin for a condition for which it is not prescribed. Do not give levofloxacin to other people, even if they have the same symptoms that you have. It may harm them.

This Medication Guide summarizes the most important information about levofloxacin. If you would like more information about levofloxacin, talk with your healthcare provider. You can ask your healthcare provider or pharmacist for information about levofloxacin that is written for healthcare professionals.

For more information call 1-866-850-2876.

What are the ingredients in levofloxacin injection?

Active ingredient: levofloxacin.

Inactive ingredients: water for injection. Levofloxacin injection single-dose vials do not contain any preservatives.

All brands listed are the trademarks of their respective owners and are not trademarks of Aurobindo Pharma Limited.

This Medication Guide has been approved by the U.S. Food and Drug Administration.

Distributed by:
AuroMedics Pharma LLC
279 Princeton-Hightstown Rd.
E. Windsor, NJ 08520

Manufactured by:
Aurobindo Pharma Limited
Hyderabad – 500038
India

Revised: July 2017

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