SEARCH · Search PubMed

Results for “Clarithromycin”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 127 records · Page 7Linked to original sources

PubMed1999

Comparison of sparfloxacin and clarithromycin in the treatment of acute bacterial maxillary sinusitis. Sparfloxacin Multicenter AMS Study Group.

Five hundred four patients were enrolled in a randomized, double-masked, multicenter study comparing the efficacy and tolerability of a 10-day regimen of sparfloxacin with a 14-day regimen of clarithromycin in the treatment of acute maxillary sinusitis. Two hundred fifty-two patients received sparfloxacin as a single 400-mg dose on day 1 and 200 mg once daily for 9 additional days, and 252 patients received clarithromycin 500 mg twice daily for 14 days. In the all-treated population, clinical success was observed at 6 to 10 days after therapy in approximately 82% of the patients in each treatment group. A total of 430 patients met the inclusion criteria for clinical assessment. The success rates in these patients were also comparable, at 83.1% and 83.4% for the sparfloxacin and clarithromycin groups, respectively. Sustained clinical success rates in the all-treated population 3 to 4 weeks after therapy were 71.6% for the sparfloxacin group and 68.6% for the clarithromycin group. All treated patients were included in the tolerability analysis. The frequency of adverse events in the clarithromycin and sparfloxacin groups was 57.9% and 48.4%, respectively. The most frequently noted adverse events were diarrhea, photosensitivity reaction, taste perversion, nausea, and abdominal pain; >96% of adverse events in the sparfloxacin group and 94% of adverse events in the clarithromycin group were of mild or moderate severity. Among adverse events at least possibly related to study drug, photosensitivity reaction was more common in the sparfloxacin group (9.5% vs. 0.4%), whereas taste perversion (8.7% vs. 0.8%) and abdominal pain (3.6% vs. 1.6%) were more common in the clarithromycin group. Thus the sparfloxacin's more convenient regimen was as effective as clarithromycin in the treatment of acute bacterial maxillary sinusitis, and the overall frequency of adverse events with sparfloxacin was comparable to that with clarithromycin.

Acute Disease↗

PubMed1999

Loracarbef versus clarithromycin in children with acute otitis media with effusion.

Two multicenter, randomized, single-masked, parallel-group studies compared loracarbef and clarithromycin with regard to efficacy, tolerability, and patient acceptance. Three hundred thirty-four children aged 6 months to 3 years with acute otitis media with effusion received loracarbef (15 mg/kg) or clarithromycin (7.5 mg/kg) orally twice daily for 10 days. Patients were assessed for the presence of the diagnostic signs and symptoms of otitis media with effusion by physical examination and pneumatic otoscopy at 48 hours pretreatment, 3 to 5 days after initiation of treatment, 0 to 3 days after the final dose (posttreatment), and 14 to 21 days later (termination). Symptoms were assigned numeric values. Symptomatic response was assessed at the posttherapy and termination visits. Tolerability was determined by assessing adverse events, and a patient acceptance survey was completed by each patient's caregiver. The combined results of these 2 studies showed that the efficacy and tolerability of loracarbef were comparable to those of clarithromycin. Adverse events were reported by 46.4% of loracarbef patients and 41.0% of clarithromycin patients, with no statistically significant difference between groups. In the intent-to-treat analysis, 57.9% of loracarbef patients were cured at the termination of the study, compared with 55.7% of clarithromycin patients. Improvement was seen in 4.1% of loracarbef patients and 2.7% of clarithromycin patients. Results of the patient acceptance survey showed a clear preference for loracarbef over clarithromycin. Difficulties with administration of treatment were reported by 36.3% of clarithromycin caregivers, compared with 7.8% of loracarbef caregivers (P < 0.001). A desire to stop treatment was reported by 23.8% of clarithromycin caregivers, compared with 7.8% of loracarbef caregivers (P < 0.001). Taste and texture issues were most frequently cited as reasons for nonacceptance.

Acute Disease↗

PubMed2002

A comparison of gemifloxacin and clarithromycin in acute exacerbations of chronic bronchitis and long-term clinical outcomes.

BACKGROUND: Gemifloxacin is an enhanced-affinity quinolone with potent activity against lower respiratory tract pathogens. OBJECTIVE: The efficacy and safety of a 5-day course of gemifloxacin were compared with those of a standard 7-day regimen of clarithromycin in patients with an acute exacerbation of chronic bronchitis (AECB). The impact of treatment on the long-term (26 weeks) clinical outcome was also assessed. METHODS: The acute phase of this randomized, double-blind study was performed in 93 centers in 7 countries. Adult patients (age >40 years) with a history of chronic bronchitis and an Anthonisen type 1 acute exacerbation (increased dyspnea, cough, and sputum purulence) were eligible. Patients receiving systemic steroids at a dose of >10 mg prednisone or the equivalent were excluded. Patients were randomized to receive gemifloxacin 320 mg once daily for 5 days or clarithromycin 500 mg twice daily for 7 days. Clinical and bacteriologic response rates were assessed at the end-of-therapy visit (days 8-12), the week 2-3 follow-up visit (days 13-24), and the week 4-5 follow-up visit (days 25-38). The long-term phase (26 weeks), which included US and Canadian participants only, evaluated the proportion of patients who remained free of a recurrence of AECB requiring additional antimicrobial therapy after resolution of the initial episode. RESULTS: Seven hundred twelve patients were randomized to treatment, 351 to gemifloxacin and 361 to clarithromycin. The long-term study included 438 patients, 214 receiving gemifloxacin and 224 receiving clarithromycin. Clinical success rates at the 2-3 week follow-up visit were 85.4% for gemifloxacin and 84.6% for clarithromycin. Bacteriologic success rates were 86.7% for gemifloxacin and 73.1% for clarithromycin. Significantly more patients receiving gemifloxacin than clarithromycin remained free of AECB recurrences (71.0% vs 58.5%, respectively; P = 0.016). Both treatments were well tolerated. CONCLUSIONS: In the acute treatment of Anthonisen type 1 AECB, a 5-day course of gemifloxacin was at least as effective as a 7-day regimen of clarithromycin. In this population, significantly more patients receiving gemifloxacin remained free of AECB recurrence after 26 weeks compared with those receiving clarithromycin.

Adult↗

PubMed2003

Efficacy and tolerability of 5-day, once-daily telithromycin compared with 10-day, twice-daily clarithromycin for the treatment of group A beta-hemolytic streptococcal tonsillitis/pharyngitis: a multicenter, randomized, double-blind, parallel-group study.

BACKGROUND: Telithromycin, a ketolide antibacterial, has been developed for the treatment of community-acquired respiratory infections. OBJECTIVE: This study compared the efficacy and tolerability of 5-day, once-daily telithromycin with 10-day, twice-daily clarithromycin in adolescents and adults with acute tonsillitis/pharyngitis caused by group A beta-hemolytic streptococci ([GABHS] Streptococcus pyogenes). METHODS: In this multicenter, randomized, double-blind, parallel-group study, adolescent (aged > or = 13 years) and adult patients with a diagnosis of GABHS tonsillitis/pharyngitis received once-daily telithromycin 800 mg for 5 days (followed by placebo for 5 days) or twice-daily clarithromycin 250 mg for 10 days. Bacteriologic and clinical outcomes were assessed at a test-of-cure visit (days 16 to 23) and a late posttherapy visit (days 31 to 45). RESULTS: A total of 526 patients were enrolled in the study, of which 463 (288 females, 175 males) were randomized to receive treatment (telithromycin, n = 232; clarithromycin, n = 231). The mean age of the telithromycin group was 30.9 years; in the clarithromycin group, it was 30.0 years. Bacterial eradication was achieved in 91.3% of telithromycin-treated patients and 88.1% of clarithromycin recipients (difference, 3.2%; 95% CI, -4.5 to 11.0). Clinical cure was achieved in 92.7% of telithromycin recipients and 91.1% of clarithromycin-treated patients (difference, 1.6%; 95% CI, -5.5 to 8.6). Bacteriologic and clinical cures for the 2 treatment groups also were similar at the late posttherapy visit. Treatment-related adverse events occurred more frequently in the telithromycin group than the clarithromycin group (67.2% vs 57.5%, respectively); diarrhea, nausea, and vomiting were significantly more common with telithromycin than with clarithromycin (P = 0.004, 0.010, and 0.001, respectively). Adverse events were generally mild. CONCLUSION: This study demonstrates that telithromycin 800 mg once daily for 5 days was an effective and generally well-tolerated treatment for tonsillitis/pharyngitis caused by GABHS, providing similar bacteriologic and clinical efficacy to clarithromycin 250 mg twice daily for 10 days in the per-protocol population.

Adolescent↗

PubMed2002

Lower concentrations of clarithromycin suppress urease activity, motility, and binding to gastric epithelial cells in Helicobacter pylori isolates.

BACKGROUND: Our previous study showed that histological scores of gastric mucosal inflammation and Helicobacter pylori density decreased even in patients who failed to eradicate Helicobacter pylori after antimicrobial therapy including clarithromycin. This may reflect indirect suppressive effects of lower concentrations of clarithromycin on Helicobacter pylori, as suggested in other Gram-negative rod infections. AIMS: To investigate whether clarithromycin suppresses virulence factors of Helicobacter pylori at sub-minimal inhibitory concentration. METHODS: Six clarithromycin-susceptible Helicobacter pylori isolates and 7 clarithromycin-resistant isolates were obtained from patients with peptic ulcer disease. These isolates were analysed for urease activity, motility, and ability to bind to gastric epithelial cells after they were incubated with or without clarithromycin at sub-minimal inhibitory concentrations. RESULTS: Incubation of Helicobacter pylori isolates with clarithromycin at sub-minimal inhibitory concentrations reduced urease activity motility, and binding to gastric epithelial cells in a dose-dependent manner. These findings were observed both in clarithromycin-susceptible and resistant strains. CONCLUSIONS: Suppressive effects of clerithromycin on virulence factors of Helicobacter pylori at sub-minimal inhibitory concentrations may be associated with observed attenuation of gastric inflammation and Helicobacter pylori density in patients who failed in bacterial eradication after triple therapy including clarithromycin.

Anti-Bacterial Agents↗

PubMed1997

Ranitidine bismuth citrate and clarithromycin twice daily in the eradication of Helicobacter pylori.

BACKGROUND: Ranitidine bismuth citrate (RBC) 400 mg when given twice daily (b.d.) for 4 weeks with clarithromycin 250 mg four times daily (q.d.s.) for the first 2 weeks effectively heals duodenal ulcers and eradicates Helicobacter pylori. AIMS: To compare two dosage regimens of clarithromycin, 250 mg q.d.s. and 500 mg b.d., used with ranitidine bismuth citrate (Pylorid) 400 mg b.d., for the eradication of H. pylori and for symptom relief in patients with active duodenal ulcers. SUBJECTS: 236 patients with active duodenal ulcer and confirmed H. pylori infection. METHODS: In a randomized, double-blind, parallel group, multi-centre study, RBC was given with clarithromycin for 2 weeks followed by 2 weeks treatment with RBC alone to allow for ulcer healing. Ulcer status was assessed by endoscopy at entry. H. pylori status was assessed by CLO Test and 13C-urea breath test (UBT) at entry and UBT alone 4 weeks after the end of treatment. At entry, during the study and at follow-up, ulcer symptoms were recorded on a scale of none, mild, moderate or severe. RESULTS: 176 patients had an evaluable UBT at least 4 weeks post-treatment. H. pylori eradication rates were 96.2% for the RBC plus clarithromycin b.d. regimen and 91.8% for the RBC plus clarithromycin q.d.s. regimen (observed data). Four weeks post-treatment, 92% of patients receiving RBC b.d. plus clarithromycin q.d.s. and 89% receiving RBC b.d. plus clarithromycin b.d. were considered symptom successes (none or mild symptoms). CONCLUSIONS: RBC 400 mg b.d. plus clarithromycin 500 mg b.d. was as effective as RBC 400 mg b.d. plus clarithromycin 250 mg q.d.s. in eradicating H. pylori and both regimens were well tolerated. The simpler dual therapy in a b.d. regimen might well encourage greater patient compliance.

Adult↗

PubMed2001

Cure of Helicobacter pylori infection in elderly patients: comparison of low versus high doses of clarithromycin in combination with amoxicillin and pantoprazole.

BACKGROUND: Advancing age may influence clarithromycin's pharmacokinetics. No studies have yet compared the effects of different dosages of clarithromycin in combination with a proton pump inhibitor and amoxicillin in elderly patients. AIM: To compare the efficacy and tolerability of clarithromycin 250 mg vs. clarithromycin 500 mg twice daily (b.d.) in combination with pantoprazole and amoxicillin in elderly patients. METHODS: One hundred and fifty-four elderly patients with H. pylori-associated ulcer disease or chronic gastritis were consecutively randomized to receive pantoprazole 40 mg daily plus amoxicillin 1 g, and either clarithromycin 250 mg b.d. (PAC 250) or clarithromycin 500 mg b.d. (PAC 500). Two months after therapy, endoscopy and gastric biopsies were repeated. RESULTS: The cure rates of H. pylori infection in the PAC 250 and PAC 500 groups were, respectively, 83% and 79% (ITT analysis) and 94% and 88% (PP analysis) (P=N.S.). Significant decreases in chronic gastritis activity both in the body (P < 0.00001) and the antrum (P < 0.0001) of the stomach were found in H. pylori-cured patients, independently of clarithromycin dosage. Four patients in PAC 250 (5%) and seven in PAC 500 (9%) reported adverse events (P=N.S.). One patient in PAC 250 (25%) and three in PAC 500 (43%) discontinued the study because of these drug-related side-effects (P=N.S.). CONCLUSIONS: In elderly patients, 1-week triple therapy with a proton pump inhibitor, amoxicillin and clarithromycin is a highly effective and well tolerated anti-H. pylori treatment. With this combination, clarithromycin at the lower dose of 250 mg b.d. achieved excel- lent cure rates and minimized adverse events and costs.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed2002

Emergence of clarithromycin-resistant Helicobacter pylori (CRHP) with a high prevalence in children compared with their parents.

BACKGROUND: Clarithromycin-resistant Helicobacter pylori (CRHP) is increasing worldwide. Clarithromycin resistance in H. pylori from familial members has not been investigated. MATERIALS AND METHODS: Biopsy specimens were taken from 13 families living in Tokyo, Yokohama, and Niigata between 1998 and 2001. Drug resistance was tested with the replica plating method. The minimum inhibitory concentrations of antimicrobial agents for H. pylori strains were determined by the agar dilution method. Molecular analyses of H. pylori strains were performed by ribosomal RNA gene restriction pattern analysis. The DNA region, associated with clarithromycin resistance, was analyzed by PCR and sequencing. RESULTS: Helicobacter pylori strains isolated from a 5-year-old-son displayed clarithromycin resistance with a mutation (A --> G at position 2143) in the 23S ribosomal RNA, whereas H. pylori strains from his parents did not. DNA analyses revealed that the boy was infected with his father's strain. The boy had repeatedly developed otitis media and received clarithromycin since the age of 2 years. Studies on an additional 12 families demonstrated that clarithromycin resistance in the children's strains reached 42.9% and was significantly higher than those of H. pylori strains from their parents (0%) or from adult patients (11.1%) (p <.05). CONCLUSIONS: The rate of clarithromycin resistance in H. pylori strains from Japanese children was extremely high, in contrast to those from their parents or adult patients. Prior history of clarithromycin usage in a child suggested development of clarithromycin resistance in resident H. pylori, which was originated from a parent.

Adult↗

PubMed1996

A randomized trial of clarithromycin as prophylaxis against disseminated Mycobacterium avium complex infection in patients with advanced acquired immunodeficiency syndrome.

BACKGROUND: Disseminated infection with Mycobacterium avium complex is the most common opportunistic infection in patients with advanced stages of the acquired immunodeficiency syndrome (AIDS). We studied the efficacy and safety of prophylactic treatment with clarithromycin, a macrolide antibiotic. METHODS: We conducted a randomized, placebo-controlled, double-blind study of clarithromycin in patients with AIDS in the United States and Europe. Entry criteria included blood cultures that were negative for M. avium complex, a Karnofsky performance score of 50 or higher, a CD4 cell count of 100 or less per cubic millimeter, and a life expectancy of at least six months. RESULTS: After the first interim analysis, the study was stopped. M. avium complex infection developed in 19 of the 333 patients (6 percent) assigned to clarithromycin and in 53 of the 334 (16 percent) assigned to placebo (adjusted hazard ratio, 0.31; 95 percent confidence interval, 0.18 to 0.53; P<0.001). During the follow-up period of about 10 months, 32 percent of the patients in the clarithromycin group died and 41 percent of those in the placebo group died (hazard ratio, 0.75; P=0.026). In the clarithromycin group, isolates from 11 of the 19 patients with M. avium complex infection were resistant to clarithromycin. Prophylaxis with clarithromycin was associated with an increased incidence of taste perversion (11 percent in the clarithromycin group vs. 2 percent in the placebo group, P<0.001) and rectal disorders (8 percent vs. 3 percent, P = 0.007); however, the frequency of more severe adverse events was similar in the two groups (7 percent and 6 percent, respectively). CONCLUSIONS: In patients with advanced AIDS, the prophylactic administration of clarithromycin is well tolerated, prevents M. avium complex infection, and reduces mortality.

AIDS-Related Opportunistic Infections↗

PubMed2001

The cytochrome P4503A4 inhibitor clarithromycin increases the plasma concentrations and effects of repaglinide.

OBJECTIVE: Our objective was to study the effects of the macrolide antibiotic clarithromycin on the pharmacokinetics and pharmacodynamics of repaglinide, a novel short-acting antidiabetic drug. METHODS: In a randomized, double-blind, 2-phase crossover study, 9 healthy volunteers were treated for 4 days with 250 mg oral clarithromycin or placebo twice daily. On day 5 they received a single dose of 250 mg clarithromycin or placebo, and 1 hour later a single dose of 0.25 mg repaglinide was given orally. Plasma repaglinide, serum insulin, and blood glucose concentrations were measured up to 7 hours. RESULTS: Clarithromycin increased the mean total area under the concentration-time curve of repaglinide by 40% (P <.0001) and the peak plasma concentration by 67% (P <.005) compared with placebo. The mean elimination half-life of repaglinide was prolonged from 1.4 to 1.7 hours (P <.05) by clarithromycin. Clarithromycin increased the mean incremental area under the concentration-time curve from 0 to 3 hours of serum insulin by 51% (P <.05) and the maximum increase in the serum insulin concentration by 61% (P <.01) compared with placebo. No statistically significant differences were found in the blood glucose concentrations between the placebo and clarithromycin phases. CONCLUSIONS: Even low doses of the cytochrome P4503A4 (CYP3A4) inhibitor clarithromycin increase the plasma concentrations and effects of repaglinide. Concomitant use of clarithromycin or other potent inhibitors of CYP3A4 with repaglinide may enhance its blood glucose-lowering effect and increase the risk of hypoglycemia.

Adult↗

PubMed1999

Prevalence of resistance to clarithromycin and its clinical impact on the efficacy of Helicobacter pylori eradication.

BACKGROUND: Triple therapy with a proton-pump inhibitor (PPI) in combination with metronidazole and clarithromycin is the method of choice for eradication of Helicobacter pylori. Failures have been primarily blamed on the development of resistance to clarithromycin. The present study investigated the prevalence and clinical significance of resistance to clarithromycin and metronidazole in determining therapeutic success of both triple therapy as a primary eradication method and high-dose dual therapy in non-responders. METHODS: On the basis of prior therapy, H. pylori-positive patients were assigned to one of two groups in the present prospective study. Group A (n = 93) included patients who had not undergone any prior eradication treatment, whereas group B (n = 15) consisted of patients who had received clarithromycin but in whom eradication had been unsuccessful. All patients underwent endoscopy with biopsy for bacterial culture and resistance studies. Patients in group A were treated with a 7-day regimen of pantoprazole (40 mg twice daily), metronidazole (500 mg twice daily), and clarithromycin (250 mg twice daily), whereas those in group B received omeprazole (40 mg three times a day) and amoxycillin (1000 mg three times a day ) for 14 days. Success of the eradication treatment was ascertained by means of the 13C urea breath test. RESULTS: In group A resistance to clarithromycin and metronidazole was identified in 3 patients (4.9%) and in 14 patients (22.9%), respectively. Eradication proved successful in 78 of 84 patients (92.6%) followed up. Two of the 3 patients with primary clarithromycin resistance and 1 of the 14 patients with metronidazole resistance did not respond to treatment. In group B isolated or combined resistance to clarithromycin was found in seven patients, whereas another four showed isolated resistance to metronidazole. Eradication proved successful in 10 of 13 controlled patients (76.9%) followed up, and only 2 patients reported severe side effects. CONCLUSION: Determination of antibiotic resistance before initiating therapy is not necessary, since primary resistance to clarithromycin is rare. The Italian triple therapy remains a highly effective primary therapeutic method. Further, routine determination of resistance in non-responders also seems to be superfluous because high-dose dual therapy is an effective and well-tolerated second-line therapy regardless of the patients' resistance status.

2-Pyridinylmethylsulfinylbenzimidazoles↗

PubMed1992

Azithromycin and clarithromycin: overview and comparison with erythromycin.

Azithromycin and clarithromycin are erythromycin analogues that have recently been approved by the FDA. These drugs inhibit protein synthesis in susceptible organisms by binding to the 50S ribosomal subunit. Alteration in this binding site confers simultaneous resistance to all macrolide antibiotics. Clarithromycin is several-fold more active in vitro than erythromycin against gram-positive organisms, while azithromycin is 2- to 4-fold less potent. Azithromycin has excellent in vitro activity against H influenzae (MIC90 0.5 microgram/ml), whereas clarithromycin, although less active against H influenzae (MIC90 4.0 micrograms/ml) by standard in vitro testing, is metabolized into an active compound with twice the in vitro activity of the parent drug. Both azithromycin and clarithromycin are equivalent to standard oral therapies against respiratory tract and soft tissue infections caused by susceptible organisms, including S aureus, S pneumoniae, S pyogenes, H influenzae, and M catarrhalis. Clarithromycin is more active in vitro against the atypical respiratory pathogens (e.g., Legionella), although insufficient in vivo data are available to demonstrate a clinical difference between azithromycin and clarithromycin. Superior pharmacodynamic properties separate the new macrolides from the prototype, erythromycin. Azithromycin has a large volume of distribution, and, although serum concentrations remain low, it concentrates readily within tissues, demonstrating a tissue half-life of approximately three days. These properties allow novel dosing schemes for azithromycin, because a five-day course will provide therapeutic tissue concentrations for at least ten days. Clarithromycin has a longer serum half-life and better tissue penetration than erythromycin, allowing twice-a-day dosing for most common infections. Azithromycin pharmacokinetics permit a five-day, single daily dose regimen for respiratory tract and soft tissue infections, and a single 1 g dose of azithromycin effectively treats C trachomatis genital infections; these more convenient dosing schedules improve patient compliance. Azithromycin and clarithromycin also are active against some unexpected pathogens (e.g., B burgdorferi, T gondii, M avium complex, and M leprae). Clarithromycin, thus far, appears the most active against atypical mycobacteria, giving new hope to what has become a difficult group of infections to treat. Gastrointestinal distress, a well known and major obstacle to patient compliance with erythromycin, is relatively uncommon with the new macrolides. Further clinical data and experiences may better define and expand the role of these new macrolides in the treatment of infectious diseases.

Azithromycin↗

PubMed1998

Ocular penetration of oral clarithromycin in humans.

Clarithromycin has a wide spectrum of activity against many gram-positive and gram-negative organisms, intracellular pathogens, and opportunistic pathogens. To examine the penetration of clarithromycin in the ocular tissues, 21 patients who underwent elective cataract surgery (Group I) received a single 500-mg dose of clarithromycin orally either 4, 8, 10, 12, or 22 hours before cataract surgery, and 21 patients who underwent elective retina/vitreous surgery (Group II) received 500 mg every 12 hours orally for 3 days before the surgery with the last dose given either 3, 6, 8, 11, or 24 hours before the surgery. Serum from all patients was assayed for clarithromycin prior to drug administration and at the time ocular specimen was taken. Aqueous, iris, and vitreous samples were also assayed for clarithromycin concentration. The concentrations of clarithromycin in the aqueous fluid 4, 8, 10, 12, and 22 hours after administration were: (mean +/- SD) 0.13+/-0.05, 0.137+/-0.11, 0.074+/-0.03, 0.06+/-0.02, and 0.074+/-0.04 microg/ml, respectively. Concentration of clarithromycin in vitreous 3, 6, 8, 11, and 24 hours after administration were: (mean +/- SD) 0.11+/-0.02, 0.257+/-0.13, 0.27+/-0.21, 0.307+/-0.26 and 0.108+/-0.07 microg/ml, respectively. The mean concentration of clarithromycin in the iris was 6.2 microg/g. In conclusion, this data suggest that clarithromycin widely penetrates and adequately concentrates in the aqueous humor, vitreous humor, and iris tissue after oral administration and therefore is effective in the management of many infectious ocular conditions.

Administration, Oral↗

PubMed1993

Clarithromycin versus cefaclor for the treatment of mild-to-moderate acute bacterial bronchitis.

Four hundred and eight outpatients with the clinical signs and symptoms of mild-to-moderate acute bronchitis of bacterial aetiology were enrolled in a multicentre, double-blind, randomized clinical trial comparing the efficacy and safety of clarithromycin and cefaclor, both administered orally. Two hundred and seven patients received clarithromycin 250 mg bd and 201 patients received cefaclor 500 mg tds for a maximum of seven days. Clinical and bacteriological evaluations were performed before treatment was initiated, during the course of treatment, and within 72 h of completing therapy; all adverse events were recorded. Two hundred and three patients in the clarithromycin group and 195 in the cefaclor group were evaluable for clinical response and 129 and 124 patients in the clarithromycin and cefaclor groups, respectively, were evaluable for bacteriological response. The clinical response rates three to five days after starting treatment and at the post-treatment assessment were 97% (193/199) and 99.5% (202/203), respectively, for the clarithromycin group and 97.4% (187/192) and 97.9% (191/195), respectively, for the cefaclor group. The bacteriological cure rates were 94.6% (122/129) for the clarithromycin group and 90.3% (112/124) for the cefaclor group. None of the differences between the groups was statistically significant. Adverse events, which were generally mild and predominantly related to the gastrointestinal tract, were reported by 5.8% of clarithromycin-treated patients and 10.4% of cefaclor-treated patients. Adverse reactions caused one patient in the clarithromycin group and three in the cefaclor group to discontinue treatment prematurely. The results of this study indicate that clarithromycin and cefaclor are comparable with respect to efficacy and safety when used as treatment for patients with mild-to-moderate acute bacterial bronchitis.

Acute Disease↗

PubMed1993

Comparison of azithromycin versus clarithromycin in the treatment of patients with upper respiratory tract infections.

The efficacy and safety of azithromycin and clarithromycin were compared in an open multicentre study involving 380 adult patients with acute otitis media, acute sinusitis, or acute streptococcal pharyngitis or tonsillitis. Patients were assigned randomly to receive azithromycin as a single dose of 500 mg daily for three days, or clarithromycin 250 mg bid for ten days. Overall clinical efficacy was found to be similar in each treatment group at day 10-14, with a satisfactory outcome (cured or improved) in 95% of azithromycin and 96% of clarithromycin patients. Bacteriological efficacy was also similar, with eradication of the pathogen in 94% and 95% of isolates, respectively, in the azithromycin and clarithromycin groups. In otitis media, a satisfactory clinical response was seen in 97% of patients in each treatment group. Azithromycin therapy resulted in a clinical response rate of 93% in sinusitis patients, with bacteriological eradication in 93% of patients. Two patients (who were cured clinically) had persistent pathogens. Similarly, clarithromycin achieved clinical response and bacteriological eradication in 95% and 92% of sinusitis patients, respectively. Pathogens persisted in two patients with clinical cure, and in one case of clinical failure. In pharyngitis or tonsillitis, Streptococcus pyogenes was eradicated successfully in 95% of patients in both groups, and the clinical success rates were 96% and 97% for azithromycin and clarithromycin, respectively. No case of clinical failure was associated with persistence of S. pyogenes infection. At the follow-up assessment of this diagnosis group, reinfection had occurred in three (8%) azithromycin patients and one (3%) clarithromycin patient, and all but one patient remained asymptomatic. Both drugs were well-tolerated, with 8.4% of patients on azithromycin and 7.4% on clarithromycin reporting adverse events, mainly gastrointestinal. It was concluded that a three-day course of azithromycin was as effective and well-tolerated as a ten-day course of clarithromycin in adults with acute upper respiratory tract infections.

Acute Disease↗

PubMed2000

Comparison of the abilities of grepafloxacin and clarithromycin to eradicate potential bacterial pathogens from the sputa of patients with chronic bronchitis: influence of pharmacokinetic and pharmacodynamic variables.

A randomized open-label study was conducted to compare the pharmacokinetics and pharmacodynamics of grepafloxacin with those of clarithromycin in patients with chronic bronchitis whose sputa were colonized with potential bacterial pathogens. Patients received oral grepafloxacin 400 mg od for 10 days (n = 15) or oral clarithromycin 500 mg bd for 10 days (n = 10). Sputum samples were collected before the first dose, 1, 4 and 8 h after a dose on day 1 and then before a dose on days 2, 3, 5, 7 and 10 to determine the time to eradication (T(erad)) of the potential bacterial pathogens. Blood samples for measurement of grepafloxacin or clarithromycin and 14-hydroxyclarithromycin concentrations were obtained before a dose and 1, 2, 4, 8 and 12 h after doses on days 1 and 5. The area under the inhibitory serum concentration-time curve over 24 h (AUIC(24)), peak serum concentration:MIC ratio (C(max):MIC) and the percentage of the dosing interval during which the serum concentration exceeded the MIC (%tau >MIC) were calculated and serum inhibitory titres (SITs) were determined. Haemophilus spp. were the predominant potential bacterial pathogens and were recovered from the sputa of 24 patients. Strains of Streptococcus pneumoniae were isolated from two patients in the grepafloxacin group and a strain of Moraxella catarrhalis was isolated from one patient in the clarithromycin group. Haemophilus spp. isolates were eradicated from the sputa of 13 of 14 (93%) patients given grepafloxacin, but from only two of 10 (20%) patients given clarithromycin (P < 0.05). In the other eight (80%) patients who received clarithromycin, the sputum cultures remained positive throughout the 10 day course. Grepafloxacin eliminated potential bacterial pathogens more quickly than clarithromycin (median T(erad) 4 h versus 76 h). The S. pneumoniae strains were eradicated by grepafloxacin within 4 h and the single M. catarrhalis strain was eradicated by clarithromycin within 1 h. The greater efficacy of grepafloxacin, compared with that of clarithromycin, in terms of the incidence and speed of eradication of the Haemophilus spp. isolates, was associated with higher median values of AUIC(24) (169 SIT(-1)*h versus 8.1 SIT(-1)*h), C(max):MIC ratio (23.6 versus 0.7) and %tau >MIC (100% versus 0%). A Hill-type model adequately described the relationship between the percentage probability of eradicating potential bacterial pathogens from sputa and the plasma grepafloxacin concentration.

Adolescent↗

PubMed1998

Long-term outcomes of treatment of Mycobacterium avium complex bacteremia using a clarithromycin-containing regimen.

OBJECTIVES: To describe the long-term outcomes of treatment of AIDS-related Mycobacterium avium complex (MAC) bacteremia using a standard clarithromycin-based regimen. DESIGN: Retrospective study of patients with MAC bacteremia diagnosed between April 1992 and April 1995. SETTING: An urban AIDS clinic SUBJECTS: One hundred seventy-six consecutive patients with MAC bacteremia. INTERVENTIONS: Clarithromycin 500 mg twice daily, ethambutol 800 or 1200 mg daily, and clofazimine 100 mg daily. MAIN OUTCOME MEASURES: Late treatment failure (defined as a positive blood culture more than 90 days after starting treatment), clarithromycin susceptibility of initial and treatment-failure isolates, DNA fingerprinting of isolates from treatment failures. RESULTS: Two out of 176 (1.1%) baseline isolates were resistant to clarithromycin. One hundred and fifty-one patients were treated for MAC bacteremia, 144 (95%) with the standard regimen. Of the 117 patients who survived > 90 days after starting therapy, 25 (21%) met the criteria for late treatment failure. Of the 22 treatment-failure isolates available for susceptibility testing, 19 (86%) were resistant to clarithromycin. Therefore, 13% of patients treated using the standard regimen (19 out of 144) had treatment failure associated with the emergence of clarithromycin resistance. Using logistic regression, non-compliance was associated with treatment failure (P = 0.02). Fourteen out of the 17 (82%) evaluable paired isolates had identical DNA fingerprint patterns, whereas three pairs showed that a different strain of MAC was present at the time of treatment failure. CONCLUSIONS: Initial resistance to clarithromycin was rare during this period. However, late treatment failure associated with the emergence of clarithromycin resistance was relatively common during long-term follow-up. Most late treatment failures represented emergence of clarithromycin resistance in the initial strain.

AIDS-Related Opportunistic Infections↗

PubMed2001

Efficacy and safety of clarithromycin versus erythromycin for the treatment of pertussis: a prospective, randomized, single blind trial.

BACKGROUND: Pertussis is still a prevalent public health problem, and antibiotic therapy may decrease disease severity and limit communicability. Erythromycin is the recommended antibiotic for treatment and prophylaxis of pertussis; however, side effects of erythromycin limit its usefulness in some patients. Clarithromycin, a newer macrolide, has good in vitro activity against Bordetella pertussis and a better side effect profile. GOALS OF THE STUDY: To compare the microbiologic and clinical efficacy and the clinical safety of a 7-day course of clarithromycin vs. a 14-day course of erythromycin in children with pertussis. DESIGN: Prospective, randomized, single blind (investigator), parallel group trial. METHODS: Children from 1 month to 16 years of age presenting with a clinically defined pertussis syndrome were eligible for the study. After obtaining informed written consent, we randomized patients to receive either clarithromycin (7.5 mg/kg/dose twice a day for 7 days) or erythromycin (13.3 mg/kg/dose three times a day for 14 days). Nasopharyngeal cultures for B. pertussis were performed at enrollment and after end of treatment. Clinical assessments were performed at enrollment, at end of treatment and at a 1-month follow-up visit. Adverse event data were collected throughout the study. RESULTS: The clarithromycin (n = 76) and erythromycin (n = 77) groups were well-matched for age and previous pertussis immunization. Microbiologic eradication and clinical cure rates were 100% (31 of 31) for clarithromycin and 96% (22 of 23) for erythromycin. The clarithromycin group had significantly fewer adverse events [45% (34 of 76) for clarithromycin vs. 62% (48 of 77) for erythromycin; P = 0.035], and compliance with the medication regimen was significantly higher in these patients. CONCLUSIONS: A 7-day regimen of clarithromycin and a 14-day course of erythromycin were equally effective for treatment of pertussis. Clarithromycin was better tolerated than conventional erythromycin therapy.

Anti-Bacterial Agents↗