Comparison of the adverse event profiles of levofloxacin 500 mg and 750 mg in clinical trials for the treatment of respiratory infections.

OBJECTIVE: To compare safety data with levofloxacin 500 mg and 750 mg from clinical trials for the treatment of respiratory infections. METHODS: We compared adverse event data for levofloxacin 500 mg and 750 mg from clinical trials in acute bacterial sinusitis, acute bacterial exacerbation of chronic bronchitis, and community-acquired pneumonia. Adverse events occurring after the initiation of therapy were classified as treatment-emergent adverse events (TEAE); drug-related adverse events (DRAE) were TEAE assessed by the clinical investigator as definitely/very likely or probably related to levofloxacin therapy. RESULTS: Overall, the safety profile of the two doses was similar but not identical. TEAE occurred in 49.0% (1601/3268) of those treated with 500 mg and in 45.5% (519/1141) of those treated with 750 mg (p = 0.042); the corresponding rates of DRAE were 7.6% (248/3268) and 8.0% (91/1141) (p = 0.699). There was no statistically significant difference in terms of overall TEAE and DRAE rates within each of the three infectious conditions, but there were in specific events, all of which are expected with levofloxacin therapy. The limitations of this analysis include that it utilized a subset of available safety data, that it includes data only from clinical trials, and that we report primarily on events occurring in > or = 2% of patients. CONCLUSIONS: Given similar adverse event profiles and the advantages of higher dose therapy, including shorter courses of therapy and potential impact on preventing resistance, clinicians should consider utilizing the 750 mg dose of levofloxacin when choosing between dosage strengths for treatment of indicated infections.

Levofloxacin 750 mg QD for five days versus amoxicillin/clavulanate 875 mg/125 mg BID for ten days for treatment of acute bacterial exacerbation of chronic bronchitis: a post hoc analysis of data from severely ill patients.

This post hoc analysis of data from a previous randomized, blinded, multicenter, parallel, noninferiority study assessed the bacterial etiology, symptom resolution, and tolerability of severe acute bacterial exacerbation of chronic bronchitis (ABECB) patients treated with either levofloxacin 750 mg QD for 5 days or amoxicillin/clavulanate 875 mg/125 mg BID for 10 days. Severe ABECB was defined as ABECB and forced expiratory volume in 1 second (FEV(1)) <50% of the predicted value, or (FEV(1)) of 50% to 65% of the predicted value plus comorbidities, or > or =4 exacerbations per year. A total of 369 patients were included in the intent-to-treat (ITT) population (187 treated with levofloxacin and 182 treated with amoxicillin/clavulanate), and 175 patients were microbiologically assessable (MA) (86 treated with levofloxacin and 89 treated with amoxicillin/clavulanate). In the ITT population, the mean age was 58.7 years, 49.1 % were male, and 48.2% were current smokers. At the on-treatment visit, a significantly higher proportion of MA patients in the levofloxacin group resolved purulent sputum production (57.5% vs 35.6%; P < 0.006), sputum production (65.4% vs 45.3%; P < 0.013), and cough (60.0% vs 44.0%; P < 0.045), compared with the amoxicillin/clavulanate group. However, no significant between-group differences were observed at posttreatment. A total of 341 pathogens were isolated, of which 143 (41.9%) were traditional ABECB flora, 181 (53.1%) were other gram-negative organisms, and 17 (5.0%) were gram-positive organisms. Overall susceptibility of the pathogens was 97.1% for levofloxacin and 90.6% for amoxicillin/clavulanate (P < 0.001). The prevalence of treatment-emergent adverse events was 42.1 % in patients who received levofloxacin and 48.6 % in those who received amoxicillin/clavulanate (95% CI,-4.0 to 17.0).

Levofloxacin 750-mg for 5 days for the treatment of hospitalized Fine Risk Class III/IV community-acquired pneumonia patients.

BACKGROUND: The efficacy and safety of 750-mg, 5-day levofloxacin was recently shown to be comparable to 500-mg, 10-day levofloxacin in a randomized, double-blind, multicentre clinical trial for mild-to-severe community-acquired pneumonia (CAP). This subgroup analysis attempted to compare the safety and efficacy of a short-course levofloxacin regimen with traditional levofloxacin dosing for PSI Class III/IV patients. METHODS: This retrospective, subgroup analysis focused on Pneumonia Severity Index Class III and IV patients enrolled in the study. Measurements included clinical and microbiological success rates, adverse events, and symptom resolution by day 3 of therapy. RESULTS: Of the 528 patients in the ITT population, 219 (41.5%) were categorized as PSI Class III/IV and included in this analysis. Among the clinically evaluable patients, 90.8% (69/76) of patients treated with the 750-mg regimen achieved clinical success, compared with 85.5% (71/83) treated with 500-mg levofloxacin (95% CI,-15.9 to 5.4). Eradication rates in the microbiologically evaluable population were comparable for the 750- and 500-mg regimens (88.9% vs 87.5%, respectively; 95% CI,-18.3 to 15.6). Both regimens were well tolerated and had comparable safety profiles. A greater proportion of patients in the 750-mg treatment group experienced resolution of fever (48.4% vs 34.0%; P=.046) and purulent sputum (48.4% vs 27.5%; P=.007) by day 3 of therapy. CONCLUSIONS: The 750-mg, 5-day levofloxacin course achieved comparable clinical and microbiologic efficacy to the 500-mg, 10-day regimen. By day 3 of therapy, a greater proportion of patients in the 750-mg group had objective and subjective resolution of fever. Further research is needed to determine the economic significance of short-course levofloxacin therapy.

Clinical implications of 750 mg, 5-day levofloxacin for the treatment of community-acquired pneumonia.

OBJECTIVE: To evaluate the time to symptom resolution and i.v.-to-p.o. transition in community-acquired pneumonia (CAP) patients treated with 750 mg or 500 mg levofloxacin. RESEARCH DESIGN: A retrospective, subset analysis of a multicenter, randomized, double-blind, controlled trial comparing 750 mg levofloxacin for 5 days to 500 mg levofloxacin for 10 days for the treatment of CAP. PATIENTS AND METHODS: A total of 528 CAP patients were included. Baseline symptoms were re-evaluated on Day 3 of therapy, and time to i.v.-to-p.o. transition was recorded for inpatients. RESULTS: For the overall population, 67.4% of patients receiving 750 mg levofloxacin had resolution of fever by Day 3 of therapy, compared to 54.6% of 500 mg treated patients (P = 0.006). Patients who started on 750 mg levofloxacin i.v. (N = 108) transitioned to p.o. in an average of 2.68 days while those starting on 500 mg i.v. (N = 124) transitioned in 2.95 days (P = 0.144). The median time for i.v.-to-p.o. switch was 2.35 days and 2.75 days for patients receiving 750 mg and 500 mg levofloxacin, respectively (P = 0.098, log rank test). By Day 3 of therapy, 68% of patients receiving the 750 mg dose had transitioned from i.v. to p.o. levofloxacin, compared with 61% of the 500 mg group (P = 0.280). The safety profiles were comparable for the two regimens. CONCLUSIONS: The 750 mg levofloxacin dose resulted in a greater proportion of patients with resolution of CAP symptoms by Day 3 when compared with 500 mg therapy. Consequently, the 750 mg regimen trended toward more rapid transition to p.o., potentially resulting in lower overall drug costs. Time to switch from i.v. to p.o. was determined by the investigators' discretion rather than a set protocol. Additionally, length of stay data was not collected in this study, which can significantly impact overall healthcare costs. Further research is required to fully understand the economic impact of the 750 mg, 5-day levofloxacin regimen.

Levofloxacin efficacy in the treatment of community-acquired legionellosis.

BACKGROUND: Although fluoroquinolones possess excellent in vitro activity against Legionella, few large-scale clinical trials have examined their efficacy in the treatment of Legionnaires disease. Even fewer studies have applied rigorous criteria for diagnosis of community-acquired Legionnaires disease, including culture of respiratory secretions on selective media. METHODS: Data from six clinical trials encompassing 1,997 total patients have been analyzed to determine the efficacy of levofloxacin (500 mg qd or 750 mg qd) in treating patients with community-acquired pneumonia (CAP) due to Legionella. RESULTS: Of the 1,997 total patients with CAP from the clinical trials, 75 patients had infection with a Legionella species. Demographics showed a large portion of these patients were < 55 years of age and nonsmokers. More than 90% of mild-to-moderate and severe cases of Legionella infection resolved clinically at the posttherapy visit, 2 to 14 days after treatment termination. No deaths were reported for any patient with Legionnaires disease treated with levofloxacin during the studies. CONCLUSIONS: Levofloxacin was efficacious at both 500 mg for 7 to 14 days and 750 mg for 5 days. Legionnaires disease is not associated only with smokers, the elderly, and the immunosuppressed, but also has the potential to affect a broader demographic range of the general population than previously thought.

Efficacy of 750-mg, 5-day levofloxacin in the treatment of community-acquired pneumonia caused by atypical pathogens.

BACKGROUND: Current recommended durations for treatment of atypical community-acquired pneumonia (CAP) range from 10 to 21 days. However, antibiotics such as the fluoroquinolones may allow for effective, short-course regimens. OBJECTIVE: This study evaluated the efficacy of 750 mg levofloxacin for 5 days compared to a 500-mg, 10-day levofloxacin regimen for the treatment of atypical CAP. METHODS: A randomized, active-controlled, double-blind, multicenter study was conducted within the United States. Of the 528 patients enrolled in the study, 149 were diagnosed with CAP due to Legionella pneumophila, Chlamydia pneumoniae, or Mycoplasma pneumoniae. Patients' baseline symptoms were re-evaluated on Day 3 of therapy. Clinical efficacy and resolution of CAP symptoms were evaluated at the posttherapy visit (7-14 days after the last dose of active drug). RESULTS: This report represents a subgroup analysis of a previous clinical study. Among the 123 clinically evaluable patients diagnosed with atypical CAP (26 patients were unevaluable), the clinical success rates were 95.5% (63 of 66 patients) for the 750-mg group and 96.5% (55 of 57 patients) for the 500-mg group (95% CI for success rate of the 500-mg group minus that of the 750-mg group, -6.8 to 8.8). At the poststudy evaluation (31-38 days after treatment began), relapse occurred in

High-dose, short-course levofloxacin for community-acquired pneumonia: a new treatment paradigm.

Levofloxacin demonstrates concentration-dependent bactericidal activity most closely related to the pharmacodynamic parameters of the ratio of area under the concentration-time curve (AUC) to minimum inhibitory concentration (MIC) and the ratio of peak plasma concentration (C(max)) to MIC. Increasing the dose of levofloxacin to 750 mg exploits these parameters by increasing peak drug concentrations, allowing for a shorter course of treatment without diminishing therapeutic benefit. This was demonstrated in a multicenter, randomized, double-blind investigation that compared levofloxacin dosages of 750 mg per day for 5 days with 500 mg per day for 10 days for the treatment of mild to severe community-acquired pneumonia (CAP). In the clinically evaluable population, the clinical success rates were 92.4% (183 of 198 persons) for the 750-mg group and 91.1% (175 of 192 persons) for the 500-mg group (95% confidence interval, -7.0 to 4.4). Microbiologic eradication rates were 93.2% and 92.4% in the 750-mg and 500-mg groups, respectively. These data demonstrate that 750 mg of levofloxacin per day for 5 days is at least as effective as 500 mg per day for 10 days for treatment of mild-to-severe CAP.