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PubMed2004

Effect of multiple doses of clarithromycin and amoxicillin on IL-6, IFNgamma and IL-10 plasma levels in patients with community acquired pneumonia.

Inflammation is crucial for the pathogenesis of both infectious and chronic obstructive pulmonary diseases. It is therefore important to modulate pulmonary inflammation in patients with these lung disorders. Macrolide antibiotics modulate inflammation in vitro and in in vivo by inhibiting the production of proinflammatory cytokines and prostaglandin E2, neutrophil chemotactic activity and elastase activity. This study evaluates the effect of clarithromycin (500 mg b.i.d. x 7 days) in comparison to amoxicillin (1 g t.i.d. x 7 days) in patients with community acquired pneumonia by testing plasma levels of IL-6, IFNgamma and IL-10 before starting therapy and at the 3rd and 7th days of therapy. Clarithromycin significantly decreased plasma levels of IL-6 and significantly increased those of IFNgamma and IL-10 at the 3rd and 7th day in comparison to basal levels. In patients treated with amoxicillin a significant decrease in IL-6 plasma levels was observed at the 7th day of therapy, probably in relation to the resolution of inflammatory symptoms. In the same patients IFNgamma plasma levels decreased during treatment while IL-10 plasma levels were unaffected.

Administration, Oral↗
PubMed2006

Effect of clarithromycin on rhinovirus-16 infection in A549 cells.

Clarithromycin (CM) has been found to inhibit the production of the intercellular adhesion molecule (ICAM)-1 and the secretion of interleukin (IL)-6 and IL-8, which may have beneficial effects on the pathophysiological changes related to rhinovirus (RV) infection. The effect of CM on RV infection in A549 cells was therefore investigated. Cells were pre-treated with 1, 10 or 100 microM CM, either starting 3 days before infection and continuing thereafter, or by addition at the time of infection. RV titre, as measured by culture on Medical Research Council 5 cells, was reduced by CM, with the degree of reduction being greater when CM was added 3 days before infection than when it was added at the time of infection. CM treatment inhibited the RV-induced increase in ICAM-1 mRNA and protein, as well as the RV-induced secretion of IL-1beta, IL-6, and IL-8. These effects were greater in cells treated with 10 microM than in those treated with 100 microM CM, and the maximum effect was observed 3 days after viral infection. In contrast, secretion of IL-8 was not inhibited significantly when CM was added at the time of viral infection. The findings of this study suggest that, in A549 cells, clarithromycin inhibits the induction of intercellular adhesion molecule-1 expression, cytokine elaboration, and viral infection.

Cells, Cultured↗
PubMed1998

Erythromycin and clarithromycin attenuate cytokine-induced endothelin-1 expression in human bronchial epithelial cells.

Erythromycin and its fourteen-member macrolide analogues have attracted attention for their efficacy in bronchial asthma. However, their mechanisms of action remain unclear. We evaluated the effects of the macrolide antibiotics on endothelin-1 (ET-1) expression in normal and transformed human bronchial epithelial cells, one of the sources of this potent bronchoconstrictor important in the pathogenesis of asthma. Human bronchial epithelial cells were obtained from the resected bronchi, and the effect of several antimicrobial and antiasthmatic drugs on the production and messenger ribonucleic acid (mRNA) levels of ET-1 was evaluated. Bronchoepithelial cells were also isolated from the mucosa of asthmatic patients under fibreoptic bronchoscopy, and the modulating effects of the drugs were studied. Erythromycin and clarithromycin uniquely suppressed mRNA levels as well as the release of ET- at therapeutic and non-cytotoxic concentrations (percentage inhibition of ET-1 protein release: 26.4+/-5.22% and 31.2+/-7.45%, respectively, at 10(-6) M). Furthermore, erythromycin and clarithromycin inhibited ET-1 expression in bronchoepithelial cells from patients with chronic, stable asthma. A glucocorticosteroid, dexamethasone, also inhibited ET-1 expression. In contrast, theophylline, salbutamol and FK506 had no effect on ET-1 production. Our findings demonstrated that these fourteen-member macrolide antibiotics had an inhibitory effect on endothelin-1 expression in human bronchial epithelial cells. Moreover, this new mode of action may have some relevance to their clinical efficacy in bronchial asthma.

Adult↗
PubMed1992

Physicochemical properties and stability in the acidic solution of a new macrolide antibiotic, clarithromycin, in comparison with erythromycin.

Clarithromycin (6-O-methylerythromycin), a new 14-membered macrolide antibiotic, has been studied to clarify its physicochemical properties and stability in acidic solution, as compared with erythromycin (EM). The solubility of clarithromycin (CAM) in distilled water was lower than that of EM and decreased with increasing temperature. The solubilities of CAM and EM in the phosphate buffer solution at 37 degrees C decreased with an increasing pH and kept constant above pH 9. From pH-solubility profiles, the dissociation constants of CAM and EM were determined to be 8.76 and 8.36, respectively. The partition coefficient of CAM took a higher value than that of EM and increased with an increasing pH. In the acidic solution, the decomposition of CAM and EM obeyed the pseudo-first order kinetics. From the decomposition rate constants, the half life (T1/2) of CAM and EM were determined. In pH 1.39, CAM degraded with a T1/2 of 17 min while EM kinetics corresponded to a T1/2 of 3 s. Therefore, CAM was 340-fold more stable in pH 1.39 and markedly more stable in the acidic solution than EM.

Clarithromycin↗
PubMed2002

Characterization and quantitation of clarithromycin polymorphs by powder X-ray diffractometry and solid-state NMR spectroscopy.

Characterization of clarithromycin polymorph was performed by solid-state cross polarization and magic angle spinning (CP/MAS) 13C-NMR spectroscopy. Two polymorphs, form II and form I, of clarithromycins indicated characteristic resonances of C1 carbonyl carbon at 176.2 and 175.2 ppm, respectively. Since each peak of C1 carbon was well separated in the spectrum of the two polymorphs, we performed quantitative analysis of the polymorphic fraction from the peak area of these peaks. The peak area of form I was found to linearly increase with an increase of its content, with a correlation coefficient of above 0.99. Solid-state NMR was found to be a useful technique to determine the characteristics of the polymorphic forms.

Clarithromycin↗
PubMed1999

Clarithromycin associated with torsades de pointes.

Two cases of QT prolongation and torsades de pointes (TdP) are presented. The patients had been taking clarithromycin (400 mg/day) for respiratory disease. Although erythromycin is reportedly associated with TdP, this is the first report of clarithromycin associated with TdP in the absence of other drugs already known to produce QT prolongation.

Aged↗
PubMed2003

An economic evaluation of sequential i.v./po moxifloxacin therapy compared to i.v./po co-amoxiclav with or without clarithromycin in the treatment of community-acquired pneumonia.

STUDY OBJECTIVE: To evaluate costs, clinical consequences, and cost-effectiveness from a German and French health-care system perspective of sequential i.v./po moxifloxacin monotherapy compared to co-amoxiclav with or without clarithromycin (AMC +/- CLA) in patients with community-acquired pneumonia (CAP) who required parenteral treatment. METHODS: Costs and consequences over 21 days were evaluated based on clinical cure rates 5 to 7 days after treatment and health resource use reported for the TARGET multinational, prospective, randomized, open-label trial. This trial compared sequential i.v./po monotherapy with moxifloxacin (400 mg qd) to i.v./po co-amoxiclav (1.2 g i.v./625 mg po tid) with or without clarithromycin (500 mg bid) for 7 to 14 days in hospitalized patients with CAP. Since no country-by-treatment interaction was found in spite of some country differences for length of hospital stays, resource data (antimicrobial treatment, hospitalization, and out-of-hospital care) from all centers were pooled and valued using German and French unit prices to estimate CAP-related cost to the German Sickness Funds and French public health-care sector, respectively. RESULTS: Compared to AMC +/- CLA, treatment with moxifloxacin resulted in 5.3% more patients achieving clinical cure 5 to 7 days after therapy (95% confidence interval [CI], 1.2 to 11.8%), increased speed of response (1 day sooner for median time to first return to apyrexia, p = 0.008), and a reduction in hospital stay by 0.81 days (95% CI, - 0.01 to 1.63) within the 21-day time frame. Treatment with moxifloxacin resulted in savings of 266 euro and 381 euro for Germany and France respectively, primarily due to the shorter length of hospital stay. Cost-effectiveness acceptability curves show moxifloxacin has a > or = 95% chance of being cost saving from French and German health-care perspectives, and higher probability of being cost-effective at acceptability thresholds up to 2,000 euro per additional patient cured. CONCLUSION: i.v./po monotherapy with moxifloxacin shows clinical benefits including increased speed of response and is cost-effective compared to i.v./po AMC +/- CLA in the treatment of CAP.

Administration, Oral↗
PubMed2001

Phase II trial of clarithromycin and pamidronate therapy in myeloma.

A phase II study to further evaluate any possible antimyeloma activity of clarithromycin was conducted following a report of possible clinical efficacy. Twenty patients, 11 male and 9 female with a median age of 73 yr, received clarithromycin 500 mg twice daily with monthly intravenous infusions of disodium pamidronate. None of the study patients received concomitant cytotoxic or steroid therapy. Ten patients had relapsed disease, five had refractory disease, four were previously untreated, and one patient was unsuitable for cytotoxic therapy. The median number of previous treatment modalities was 1.5. Serum M protein levels and urinary M protein excretion were monitored along with other parameters to assess response. Median duration of therapy was 16 wk and six patients had dose escalation. A significant decrease in M protein production occurred in one patient at wk 12 of therapy, which maximized following dose escalation to a 47% decrease from baseline. Two patients had incremental but unsustained M protein reductions. Serum/urine M protein levels remained static in six patients and rose in the remaining six evaluable patients. The M protein response rates in this study are much lower than those previously reported and do not confirm efficacy. In addition, the recently postulated antimyeloma activity of pamidronate may explain some of the M protein decreases.

Administration, Oral↗
PubMed1999

Hypoglycemia induced by interaction between clarithromycin and disopyramide.

A 59-year-old man receiving hemodialysis was hospitalized due to severe hypoglycemic attack. The patient had been treated with disopyramide (50 mg/day) because of paroxysmal atrial fibrillation. Hypoglycemia occurred after taking clarithromycin (CAM, 600 mg/day), a macrolide antibiotic. The serum disopyramide concentration reached 8.0 micrograms/ml (23.6 microM) in the presence of CAM, while it was 1.5 micrograms/ml before the addition of CAM. A 75 g oral glucose tolerance test and daily profiles of blood glucose value showed that blood glucose levels were significantly lower in the presence of CAM and disopyramide compared to that in the absence of these drugs. The Turner index in the presence of CAM and disopyramide was significantly higher than that in the absence of these drugs, suggesting that a toxic concentration of disopyramide enhanced insulin secretion, resulting in the induction of hypoglycemic attacks, in which the inhibitory effects of CAM on the hepatic chytochrome P-450 might be involved. QT and QTc intervals were prolonged in the presence of CAM and disopyramide, but torsades de points were not observed in this patient receiving nicorandil (15 mg/day). Thus, it should be taken into account that life-threatening hypoglycemia may result from the interaction between clarithromycin and disopyramide.

Anti-Arrhythmia Agents↗
PubMed1998

One-week triple therapy with omeprazole, clarithromycin, and nitroimidazole for Helicobacter pylori infection in children and adolescents.

BACKGROUND: Resolution of Helicobacter pylori infection is important in the management of peptic ulcer disease and reduces peptic ulcer recurrence in both adults and children. Various anti-H pylori treatment regimens have been proposed, reflecting the incomplete clinical success of each. A combination of omeprazole, clarithromycin, and tinidazole, given for 1 week, has been shown to be highly tolerable and effective, achieving a success rate of >90% in the adult population. OBJECTIVE: The aim of this study was to evaluate this short-term regimen in pediatric and adolescent populations. METHODS: The study group consisted of 35 children referred for evaluation of dyspeptic symptoms. They all underwent upper gastrointestinal endoscopy, in which H pylori infection was confirmed by rapid urease test and/or histologic staining. They were given omeprazole (20 mg twice daily), clarithromycin (250 mg twice daily), and tinidazole or metronidazole (500 mg twice daily) for 1 week. The patients were divided into two groups: those who received the first course of anti-H pylori therapy during this study (group 1) and those who had previously received standard metronidazole and bismuth combination therapies that failed to eradicate H pylori (group 2). Therapeutic efficacy was assessed by a 13C-urea breath test performed 4 weeks after completion of treatment. Results. The 35 study patients had a mean age of 15.9 years (range, 10 to 19) and included 19 males and 16 females, of whom 22 were born in Israel and 13 were immigrants from the former USSR. There were 27 patients (77. 1%) in group 1 and 8 patients (22.9%) in group 2. Endoscopic findings were nodular gastritis (14), gastritis (11), gastric ulcer (1), duodenal ulcer (5), and duodenitis (4). H pylori resolution was significantly higher in group 1 patients (24/27, 88.9%) than in group 2 patients (1/8, 12.5%). There was no difference between patients with nodular gastritis and those with nonnodular gastritis, and between Israeli-born patients and patients born in the former USSR. Compliance in both groups was equally good, and no major side effects were recorded. CONCLUSIONS: One-week omeprazole/clarithromycin/tinidazole triple therapy is highly tolerable and effective for treating H pylori in the pediatric age group, but previous treatment failure diminishes the likelihood of success with this regimen.

Adolescent↗
PubMedDate not supplied

Triple therapy with clarithromycin, amoxicillin and omeprazole for Helicobacter pylori eradication in children and adolescents.

BACKGROUND: Helicobacter pylori infection presents high prevalence in developing countries, but there are few pediatric assays evaluating antimicrobial treatment. OBJECTIVE: The aim of this study was to investigate Helicobacter pylori eradication rate using a short regimen (7 and 10 days) of triple therapy with clarithromycin, amoxicillin and omeprazole. PATIENTS AND METHODS: Twenty-five Hp positive patients who presented severe epigastralgia, were submitted to antimicrobial treatment with amoxicillin (50 mg/kg/day--maximum dose 1 g bid), clarithromycin (30 mg/kg/day--maximum dose 500 mg bid) and omeprazole (0.6 mg/kg/day--maximum dose 20 mg bid) during 7 or 10 days. After 2 months, clinical symptoms were evaluated and gastric biopsies were taken to test Hp eradication. RESULTS: Overall eradication rate was achieved in 16/25 patients (64%--IC(95% = 45-83%), in 11/15 (73%--IC(95%) = 51-95%) patients who used 10 days therapy course and in 5/10 (50%--IC(95%) = 19-81%) who used 7 days therapy course. Eradication drugs were well accepted and adverse effects were reported in two patients (8%). CONCLUSIONS: This triple therapy regimen had moderate efficacy (64%). The data suggests that 10 days therapy course achieves better eradication rate (73%) than 7 days course (50%) to treat Hp infection in our population.

Adolescent↗
PubMedDate not supplied

[Clarithromycin combined with pyrimethamine in cerebral toxoplasmosis--a report of 2 cases].

The authors report the use and the outcome of claritromycin associated with pyrimethamine in the treatment of toxoplasma encephalites in two patients with AIDS. Both patients had the diagnosis stablished on clinical grounds, positive sorology (IgG) for toxoplasmosis and computed-tomographic (CT) scan of the brain showing lesions consistent with T. gondii encephalitis. The two patients were initially treated with pyrimethamine and sulfadiazine, which was changed to clindamycin due to allergic reactions. These reactions (skin rash) occurred with clindamycin as well and the patients were treated with claritromycin and pyrimethamine. The scheduled regimens were 1.5 to 2 g of clarithromycin plus 25 mg of pyrimethamine. The clinical response was very good in both cases with regression of neurologic signs and encephalitic abnormalities observed on CT scan. The authors suggest that clarithromycin associated with pyrimethamine may be an alternative treatment for toxoplasmosis in AIDS patients, who cannot receive or tolerate sulfa treatment.

AIDS-Related Opportunistic Infections↗
PubMed1995

Triple therapy with ranitidine, clarithromycin, and metronidazole in the treatment of Helicobacter pylori.

BACKGROUND: To determine whether a triple therapy regimen for the treatment of Helicobacter pylori infection, consisting of ranitidine 300 mg q.i.d., clarithromycin 500 mg t.i.d., and metronidazole 500 mg t.i.d. would provide a safe and effective treatment regimen, we performed an open prospective study in 20 consecutive patients with proven H. pylori-associated non-ulcer dyspepsia or peptic ulcer disease. METHODS: The percentage of patients in whom eradication of H. pylori succeeded was determined. A semiquantitative assessment of histology was performed, and the results were analysed using Wilcoxon's matched-pairs ranks tests; side effects were noted and graded. RESULTS: Eradication was achieved in 19 of 20 patients, i.e. in 95% (confidence interval 85-100%). Eradication of the bacterium led to a significant improvement in semiquantitative histology scores; active antral inflammation decreased from (mean +/- SEM) 1.84 +/- 0.19 to 0.21 +/- 0.16 (p = 0.0004) and chronic antral inflammation from 2.47 +/- 0.14 to 1.16 +/- 0.14 (p = 0.0002); active gastric body inflammation decreased from 0.95 +/- 0.19 to 0.00 +/- 0.00 (p = 0.0015) and chronic inflammation from 1.68 +/- 0.17 to 0.32 +/- 0.11 (p = 0.0007). Side effects occurred in 45% of patients, but in over half of these patients only mild side effects occurred. Severe side effects did not occur, none of the patients discontinued the triple therapy. CONCLUSIONS: Triple therapy with ranitidine, clarithromycin, and metronidazole provides a safe and effective treatment of H. pylori infection, resulting in a high eradication rate, and in significant decrease in semiquantitative histology scores. Further prospective studies are warranted.

Adult↗
PubMed2005

Persistence of resistant Staphylococcus epidermidis after single course of clarithromycin.

We examined how a common therapy that includes clarithromycin affects normally colonizing Staphylococcus epidermidis. Samples from the nostrils of 5 patients receiving therapy were collected before, immediately after, 1 year after, and 4 years after treatment. From each patient and sample, S. epidermidis strains were isolated and analyzed for clarithromycin susceptibility and presence of the erm(C) gene. We show that macrolide-resistant strains of S. epidermidis were selected during therapy and that the same resistant strain may persist for 4 years, in the absence of further antimicrobial treatment.

Anti-Bacterial Agents↗
PubMed2005

Assessment of Helicobacter pylori clarithromycin resistance mutations in archival gastric biopsy samples.

AIM: First, to assess the clarithromycin resistance (Cla(R)) rate 1) in patients with persistent Helicobacter pylori (H. pylori) infection after eradication,2) in patients with untreated infection and 3) in patients with successful status post eradication. Second, to evaluate the techniques sequencing and line probe hybridisation INNO-LipA for resolution of uniform and mixed populations in archival gastric biopsy samples. METHODS: The genomic 2142/43 23s rRNA mutations of the 50S ribosomal subunit conferring Cla(R) were detected by PCR-based assays. RESULTS: A total of 130 patients were investigated. Out of 21 patients of a first series with persistent infection after eradication, 19 (90%; CI (95%): 67-99%) exhibited point mutations at position 2142/43. In the second series of untreated patients, primary resistance was observed in 8 out of 93 patients (9%; CI: 4-16%). In a third series of 16 successfully eradicated patients, pure wild type populations (WT; for loci 2142/43) without any minimal mutated part were found (resistance rate 0%; CI: 0-21%). Further, in all 24 biopsies with uniform mutated and in 8 of 11 biopsies with mixed populations the two molecular biological methods yielded concordant results (100%; CI: 86-100% and 73%; CI: 39-94%, respectively). CONCLUSION: In the Baden region of Switzerland, most clarithromycin resistant H. pylori strains harbour mutations at position 2142/43. The primary resistance rate is below 10%. Mixed populations, even with minor mutated part, cannot become successfully eradicated. The two investigated techniques are equally valid for resolution of uniform mutated or mixed H. pylori populations in archival biopsy material.

Anti-Bacterial Agents↗
PubMed2005

Comparative bioavailability of clarithromycin formulations in healthy brazilian volunteers.

OBJECTIVE: To compare the bioavailability of clarithromycin 500 mg tablets (Merck S.A Industrias Quimicas, Sao Paulo, SP, Brazil, used as test formulation) and Klaricid (Abbott Laboratórios do Brasil Ltda, Sao Paulo, SP, Brazil, used as reference formulation) in 24 healthy volunteers. MATERIAL AND METHODS: The study was conducted using an open, randomized, two-period crossover design with one-week interval between doses. Blood samples were collected at pre-dose, 0.33, 0.66, 1, 1.33, 1.66, 2, 2.5, 3, 4, 6, 8, 10, 12, 16, 20 and 24 hours after the administration. AUC was calculated by the trapezoidal rule extrapolation method. Cmax and tmax were compiled from the plasmatic concentration-time data. Analysis of variance was carried out using logarithmically transformed AUC(0-inf), AUC(0-24 h), Cmax and untransformed tmax. RESULTS: Intraindividual coefficient of variation (CV%) values were 14.25% and 12.62%, respectively for Cmax and AUC(0-24 h). The geometric mean values (+/- SD) for AUC(0-24 h) (microg x h/ml), AUC(0-inf) (microg x h/ml), and Cmax (microg/ml) for test medication were 18.56 (+/- 6.87), 18.8 (+/- 5.70) and 2.45 (+/- 0.88); the obtained values for reference medication were 18.29 (+/- 5.39), 19.10 (+/- 7.21) and 2.5 (+/- 0.69). 90% Cl for clarithromycin geometric mean of AUC(0-24 h), AUC(0-inf) and Cmax ratios (test/reference) were: 93.6-105.9%, 93.8-106.2% and 89- 103.2%. CCONCLUSION The test medication was considered bioequivalent to the reference medication based on the rate and extent of absorption.

Administration, Oral↗
PubMed1999

[Treatment with omeprazole, clarithromycin and amoxicillin over 6 days in patients with Helicobacter pylori-infected duodenal ulcer].

OBJECTIVE: To investigate the eradication rate of Helicobacter pylori with omeprazole, amoxicillin and clarithromycin during 6 days in patients with duodenal ulcer. To compare the reliability of the analysis of the eradication with urea-13C breath test performed one month and 3 months after therapy. To evaluate the one-year reinfection rate. PATIENTS AND METHODS: Prospective study including 99 patients with duodenal ulcer (65 with acute disease and 34 in maintenance treatment) infected by Helicobacter pylori (urease rapid test and urea-13C breath test positive). Patients were treated with omeprazole 20 mg, clarithromycin 500 mg and amoxicillin 1 g, b.i.d., during 6 days. The infection status was investigated 1 and 3 months after treatment by urea-13C breath test. The one-year reinfection rate was investigated using the same test. RESULTS: Per protocol eradication rates were 76% (95%-CI: 66-84) one month and 73% (95%-CI: 63-81) 3 months after treatment. In the intention to treat analysis, eradication rates were 74% (95%-CI: 64-82) and 70% (95%-CI: 60-79), respectively. Side effects were mild and uncommon. The rate of false negative urea-13C breath test results one month after therapy with respect to 3 months was 4.2% (95%-CI: 0.8-11.7). One-year reinfection rate determined in 56 patient was absent. CONCLUSIONS: The eradication of Helicobacter pylori with triple therapy for 6 days in patients with duodenal ulcer is not satisfactory. To investigate Helicobacter pylori infection with urea-13C breath test one month after treatment overestimates the results of the eradication. One-year reinfection rate is clinically irrelevant.

Adolescent↗
PubMed1993

Drug usage evaluation: clarithromycin as sequential therapy.

A drug usage evaluation (DUE) of the new macrolide antibiotic clarithromycin was conducted at Christ Hospital and Medical Center, an 824-bed community teaching hospital in Oak Lawn, Illinois. The purpose of this DUE was to determine whether clarithromycin was being used as early sequential therapy following other parenteral antimicrobials as recommended by the Pharmacy and Therapeutics Committee.

Administration, Oral↗