Once daily clarithromycin extended-release vs twice-daily amoxicillin/clavulanate in patients with acute bacterial sinusitis: a randomized, investigator-blinded study

A 10-Year Follow-Up of a Randomized Prospective Study of 2 Treatments for Chronic Rhinosinusitis Without Nasal Polyps and Investigation of the Impact of Gastroeosophageal Reflux Disease in the Resistance to Treatment

OBJECTIVES

To compare the 2 long-term medical strategies in chronic rhinosinusitis without nasal polyps (CRSnNP) and to identify the role of gastroesophageal reflux disease (GERD) and Helicobacter pylori as factors of treatment failure.

MATERIAL AND METHODS

Fifty-seven patients with CRSnNP were randomized into 2 therapeutic groups. The first group was treated with 4 weeks of amoxicillin/clavulanate and a short course of oral steroids. The second group received 8 weeks of clarithromycin. Sinonasal Outcome Test-20 (SNOT-20) and Lund and Mackay scores were assessed at baseline and after treatment, and GERD Health-Related Quality of Life (GERD-HRQL) questionnaire was evaluated in all patients. Patients with a GERD-HRQL score >8 received esogastroscopy and H pylori detection. Patients were followed during a 10-year period for clinical course and GERD evolution. The 10-year evolution of patients was described in terms of recurrence, medical, and surgical treatments.

RESULTS

Thirty-seven patients completed the study; SNOT-20 and Lund and Mackay scores similarly improved in both groups. Amoxicillin/clavulanate group had significantly more adverse reactions than the clarithromycin group (P = .03). After the therapeutic course, 35% (amoxicillin/clavulanate) and 41% (clarithromycin) of patients needed functional endoscopic sinus surgery (FESS). During the long-term follow-up, 54% (amoxicillin/clavulanate) and 40% (clarithromycin) of patients had late CRSnNP recurrence; FESS was performed in less than 15% of cases of recurrence. Gastroesophageal reflux disease complaint's severity was associated with late recurrence of CRSnNP.

CONCLUSION

Amoxicillin/clavulanate and clarithromycin would be competitive treatments for CRSnNP. Gastroesophageal reflux disease seems to be a negative factor for treatment response and recurrence.

In vitro activity and pharmacodynamic/pharmacokinetic parameters of clarithromycin and azithromycin: why they matter in the treatment of respiratory tract infections

Clarithromycin and azithromycin are second-generation macrolides established and widely used for treating a range of upper and lower respiratory tract infections. Extensive clinical trials data indicate that these drugs are highly effective in these applications and broadly comparable in their clinical and microbiological effectiveness. However, consideration of pharmacokinetic, metabolic, and tissue-penetration data, including the significant antibacterial activity of the metabolite 14-hydroxy-clarithromycin, plus the findings of pharmacodynamic modeling, provide evidence that the long half-life and lower potency of azithromycin predispose this agent to select for resistant isolates. Comparison of the "mutant-prevention concentrations" of clarithromycin and azithromycin, and examination of large-scale epidemiological data from Canada, also support the view that these drugs differ materially in their propensity to promote resistance among bacterial strains implicated in common respiratory infections, and that clarithromycin may offer important advantages over azithromycin that should be considered when choosing a macrolide to treat these conditions.

WITHDRAWN: Antibiotics for acute maxillary sinusitis in adults

Currently, two separate Cochrane reviews, ‘Antibiotics for acute maxillary sinusitis in adults ’ and ‘Antibiotics for clinically diagnosed acute rhinosinusitis in adults ’ describe the effect of antibiotics for acute rhinosinusitis. Although both Cochrane reviews study the same condition, they look at different populations (patients in which the diagnosis was based on clinical signs and symptoms and patients in which the diagnosis was confirmed by imaging). Because of this, the conclusions are different in these Cochrane reviews. This was confusing for clinicians who needed to read both Cochrane reviews to know which conclusions are most applicable to their patients.
 
 This review is being withdrawn and will be incorporated into the updated publication of ‘Antibiotics for clinically diagnosed acute rhinosinusitis in adults ’. This ‘merged’ review will still maintain the relevant distinction between the two populations. However, information on the effectiveness of antibiotics for rhinosinusitis will be published in the ‘merged’ Cochrane review. We will omit the comparison between antibiotics (as published in this Cochrane review) because the choice for certain antibiotics and/or doses differs according to the local antibiotic resistance patterns and therefore this comparison is less relevant.

The editorial group responsible for this previously published document have withdrawn it from publication.

Preparation, characterization and pharmacokinetics evaluation of clarithromycin-loaded Eudragit(®) L-100 microspheres

The aim of this work was to prepare pH-dependent clarithromycin microsphere formulation by emulsion solvent evaporation method, employing Eudragit(®) L-100. Prepared microspheres were evaluated by carrying out in vitro release and in vivo pharmacokinetics studies. Drug-polymer interactions were studied by differential scanning calorimetry, X-ray diffractometry analyses and results showed that clarithromycin was molecularly dispersed in the polymer. The particle size distribution of microspheres was found over the range of 10~50 μm. The drug is hardly released in the HCl solution pH 1.2 in the first 2 h, but is rapidly released in phosphate buffer pH 7.2, and the cumulated release reached 98.1 % at 8 h. The pharmacokinetic profiles were conducted open, randomized, two-period crossover design with a 7-day interval between doses in healthy beagle dogs. The results indicated that the extent of absorption of the clarithromycin-load microspheres was the same as pure drug, but different in the rate of drug absorption in vivo.

The prevalence of bacterial infection in acute rhinosinusitis: a Systematic review and meta-analysis

OBJECTIVES/HYPOTHESIS

To systematically assess the prevalence of bacterial infection in adults with acute rhinosinusitis (ARS).

METHODS

Electronic databases were systematically searched for relevant studies published up to June 2012.

RESULTS

Twenty-nine articles, evaluating a total of 9,595 patients with a clinical diagnosis of ARS, were included in the study. Of these, 14 (48%) studies required radiographic confirmation of sinusitis, one study (3%) required evidence of purulence, 10 studies (35%) required both for inclusion in the study population, and four studies (14%) required neither. The random effects model estimate of prevalence of bacterial growth on all cultures was 53.7% (CI 48.4%-59.0%), ranging from 52.5% (CI 46.7%-58.3%) in studies requiring radiographic confirmation of sinusitis to 61.1% (CI 54.0%-68.1%) in studies requiring neither radiographic evidence nor purulence on exam. Studies that obtained cultures from antral swab had a prevalence of bacterial growth of 61.0% (CI 54.7%-67.2%), whereas those utilizing endoscopic meatal sampling had a prevalence of 32.9% (CI 19.0%-46.8%).

CONCLUSIONS

Few studies evaluate the recovery of bacteria via culture in adults with a diagnosis of ABRS or ARS based on clinical criteria alone. With radiographic and/or endoscopic confirmation, antral puncture and endoscopically guided cultures produce positive bacterial cultures in approximately one-half of patients. Opportunities exist to improve diagnostic accuracy for bacterial infection in ARS.

Antibiotics for acute maxillary sinusitis in adults

BACKGROUND

Sinusitis is one of the most common diagnoses among adults in ambulatory care, accounting for 15% to 21% of all adult outpatient antibiotic prescriptions. However, the role of antibiotics for sinusitis is controversial.

OBJECTIVES

To assess the effects of antibiotics in adults with acute maxillary sinusitis by comparing antibiotics with placebo, antibiotics from different classes and the side effects of different treatments.

SEARCH METHODS

We searched CENTRAL 2013, Issue 2, MEDLINE (1946 to March week 3, 2013), EMBASE (1974 to March 2013), SIGLE (OpenSIGLE, later OpenGrey (accessed 15 January 2013)), reference lists of the identified trials and systematic reviews of placebo-controlled studies. We also searched for ongoing trials via ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP). We imposed no language or publication restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing antibiotics with placebo or antibiotics from different classes for acute maxillary sinusitis in adults. We included trials with clinically diagnosed acute sinusitis, confirmed or not by imaging or bacterial culture.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened search results, extracted data and assessed trial quality. We calculated risk ratios (RRs) for differences between intervention and control groups in whether the treatment failed or not. All measures are presented with 95% confidence intervals (CIs). We conducted the meta-analyses using either the fixed-effect or random-effects model. In meta-analyses of the placebo-controlled studies, we combined data across antibiotic classes. Primary outcomes were clinical failure rates at 7 to 15 days and 16 to 60 days follow-up. We used GRADEpro to assess the quality of the evidence.

MAIN RESULTS

We included 63 studies in this updated review; nine placebo-controlled studies involving 1915 participants (seven of the studies clearly conducted in primary care settings) and 54 studies comparing different classes of antibiotics (10 different comparisons). Five studies at low risk of bias comparing penicillin or amoxicillin to placebo provided information on the main outcome: clinical failure rate at 7 to 15 days follow-up, defined as a lack of full recovery or improvement, for participants with symptoms lasting at least seven days. In these studies antibiotics decreased the risk of clinical failure (pooled RR of 0.66, 95% CI 0.47 to 0.94, 1084 participants randomised, 1058 evaluated, moderate quality evidence). However, the clinical benefit was small. Cure or improvement rates were high in both the placebo group (86%) and the antibiotic group (91%) in these five studies. When clinical failure was defined as a lack of full recovery (n = five studies), results were similar: antibiotics decreased the risk of failure (pooled RR of 0.73, 95% CI 0.63 to 0.85, high quality evidence) at 7 to 15 days follow-up.Adverse effects in seven of the nine placebo-controlled studies (comparing penicillin, amoxicillin, azithromycin or moxicillin to placebo) were more common in antibiotic than in placebo groups (median of difference between groups 10.5%, range 2% to 23%). However, drop-outs due to adverse effects were rare in both groups: 1.5% in antibiotic groups and 1% in control groups.In the 10 head-to-head comparisons, none of the antibiotic preparations were superior to another. However, amoxicillin-clavulanate had significantly more drop-outs due to adverse effects than cephalosporins and macrolides.

AUTHORS' CONCLUSIONS

There is moderate evidence that antibiotics provide a small benefit for clinical outcomes in immunocompetent primary care patients with uncomplicated acute sinusitis. However, about 80% of participants treated without antibiotics improved within two weeks. Clinicians need to weigh the small benefits of antibiotic treatment against the potential for adverse effects at both the individual and general population levels.

Review of macrolides (azithromycin, clarithromycin), ketolids (telithromycin) and glycylcyclines (tigecycline)

The advanced macrolides, azithromycin and clarithromycin, and the ketolide, telithromycin, are structural analogs of erythromycin. They have several distinct advantages when compared with erythromycin, including enhanced spectrum of activity, more favorable pharmacokinetics and pharmacodynamics, once-daily administration, and improved tolerability. Clarithromycin and azithromycin are used extensively for the treatment of respiratory tract infections, sexually transmitted diseases, and Helicobacter pylori-associated peptic ulcer disease. Telithromycin is approved for the treatment of community-acquired pneumonia. Severe hepatotoxicity has been reported with the use of telithromycin.

Canadian clinical practice guidelines for acute and chronic rhinosinusitis

This document provides healthcare practitioners with information regarding the management of acute rhinosinusitis (ARS) and chronic rhinosinusitis (CRS) to enable them to better meet the needs of this patient population. These guidelines describe controversies in the management of acute bacterial rhinosinusitis (ABRS) and include recommendations that take into account changes in the bacteriologic landscape. Recent guidelines in ABRS have been released by American and European groups as recently as 2007, but these are either limited in their coverage of the subject of CRS, do not follow an evidence-based strategy, or omit relevant stakeholders in guidelines development, and do not address the particulars of the Canadian healthcare environment.

Advances in understanding the pathophysiology of CRS, along with the development of appropriate therapeutic strategies, have improved outcomes for patients with CRS. CRS now affects large numbers of patients globally and primary care practitioners are confronted by this disease on a daily basis. Although initially considered a chronic bacterial infection, CRS is now recognized as having multiple distinct components (eg, infection, inflammation), which have led to changes in therapeutic approaches (eg, increased use of corticosteroids). The role of bacteria in the persistence of chronic infections, and the roles of surgical and medical management are evolving. Although evidence is limited, guidance for managing patients with CRS would help practitioners less experienced in this area offer rational care. It is no longer reasonable to manage CRS as a prolonged version of ARS, but rather, specific therapeutic strategies adapted to pathogenesis must be developed and diffused.

Guidelines must take into account all available evidence and incorporate these in an unbiased fashion into management recommendations based on the quality of evidence, therapeutic benefit, and risks incurred. This document is focused on readability rather than completeness, yet covers relevant information, offers summaries of areas where considerable evidence exists, and provides recommendations with an assessment of strength of the evidence base and degree of endorsement by the multidisciplinary expert group preparing the document.

These guidelines have been copublished in both Allergy, Asthma & Clinical Immunology and the Journal of Otolaryngology-Head and Neck Surgery.

Macrolides, ketolides, and glycylcyclines: azithromycin, clarithromycin, telithromycin, tigecycline

The advanced macrolides, azithromycin and clarithromycin, and the ketolide, telithromycin, are structural analogs of erythromycin. They have several distinct advantages when compared with erythromycin, including enhanced spectrum of activity, more favorable pharmacokinetics and pharmacodynamics, once-daily administration, and improved tolerability. Clarithromycin and azithromycin are used extensively for the treatment of respiratory tract infections, sexually transmitted diseases, and Helicobacter pylori-associated peptic ulcer disease. Telithromycin is approved for the treatment of community-acquired pneumonia. Severe hepatotoxicity has been reported with the use of telithromycin.

Clinical efficacy and time to symptom resolution of 5-day telithromycin versus 10-day amoxicillin-clavulanate in the treatment of acute bacterial sinusitis

OBJECTIVE

This study compared the clinical efficacy, time to symptom resolution, and tolerability of a 5-day regimen of telithromycin with a 10-day regimen of high-dose amoxicillin-clavulanate in acute bacterial sinusitis (ABS).

RESEARCH DESIGN AND METHODS

In this multinational (41 centers in Canada, Germany, Greece, Portugal, and Turkey), open-label, noninferiority study, patients >/=18 years old (n=298) with a clinical (>7 days' symptoms) and radiological (air/fluid level, total opacification, mucosal thickening >/=10 mm) diagnosis of ABS were randomized to receive telithromycin 800 mg once daily for 5 days or amoxicillin-clavulanate 875/125 mg twice daily for 10 days. Clinical efficacy and tolerability were assessed at the test-of-cure visit (days 17-21). Time to symptom resolution was based on patients' daily diary assessment of individual symptoms.

RESULTS

The per-protocol clinical success rate (primary endpoint) with telithromycin (88.6% (109/123)) was noninferior to that with amoxicillin-clavulanate (88.8% (111/125)) (95% confidence interval: -8.9 to 8.5). In the modified intention-to-treat (mITT) population, the median time for 50% reduction of total symptom scores was significantly shorter for telithromycin (4 days) vs. amoxicillin-clavulanate (5 days; p=0.044); median times for 75% reduction of total symptom scores were: telithromycin, 7 days; amoxicillin-clavulanate, 8 days (p=0.115). The median time for reduction of total symptom scores to the absent/very mild category (mITT population) was 6 days for telithromycin vs. 8 days for amoxicillin-clavulanate (p=0.04). All treatment-emergent adverse events (TEAEs) were mostly gastrointestinal and occurred in 20.7% (30/145) of telithromycin-treated patients vs. 31.8% (47/148) of amoxicillin-clavulanate-treated patients (p=0.034). One serious AE was reported in the telithromycin group, but it was considered not to be related to treatment.

CONCLUSIONS

This open-label, randomized study demonstrated that treatment of ABS with telithromycin resulted in comparable clinical efficacy, shorter times to symptom resolution, and fewer total TEAEs than treatment with amoxicillin-clavulanate.

Antibiotics for acute maxillary sinusitis

BACKGROUND

Expert opinions vary on the appropriate role of antibiotics for sinusitis, one of the most commonly diagnosed conditions among adults in ambulatory care.

OBJECTIVES

We examined whether antibiotics are effective in treating acute sinusitis, and if so, which antibiotic classes are the most effective.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, 2007, Issue 3); MEDLINE (1950 to May 2007) and EMBASE (1974 to June 2007).

SELECTION CRITERIA

Randomized controlled trials (RCTs) comparing antibiotics with placebo or antibiotics from different classes for acute maxillary sinusitis in adults. We included trials with clinically diagnosed acute sinusitis, whether or not confirmed by radiography or bacterial culture.

DATA COLLECTION AND ANALYSIS

At least two review authors independently screened search results, extracted data and quality assessed trials. Risk ratios (RR) were calculated for differences in the intervention and control groups to see whether or not the treatment was a failure. In meta-analysing the placebo-controlled studies, the data across antibiotic classes were combined. Primary outcomes were the clinical failure rates at 7 to 15 days and 16 to 60 days follow up.

MAIN RESULTS

Fifty-seven studies were included in the review; six placebo-controlled studies and 51 studies comparing different classes of antibiotics. Five studies involving 631 participants provided data for comparison of antibiotics to placebo, when clinical failure was defined as a lack of cure or improvement at 7 to 15 days follow up. These studies found a slight statistical difference in favor of antibiotics, compared to placebo, with a pooled RR of 0.66 (95% confidence interval (CI) 0.44 to 0.98). However, the clinical significance of the result is equivocal, also considering that cure or improvement rate was high in both the placebo group (80%) and the antibiotic group (90%). Based on six studies, when clinical failure was defined as a lack of total cure, there was significant difference in favor of antibiotics compared to placebo with a pooled RR of 0.74 (95% CI 0.65 to 0.84) at 7 to 15 days follow up. None of the antibiotic preparations was superior to each other.

AUTHORS' CONCLUSIONS

Antibiotics have a small treatment effect in patients with uncomplicated acute sinusitis in a primary care setting with symptoms for more than seven days. However, 80% of participants treated without antibiotics improve within two weeks. Clinicians need to weigh the small benefits of antibiotic treatment against the potential for adverse effects at both the individual and general population level.

Comparative tolerability, safety and efficacy of tablet formulations of twice-daily clarithromycin 250 mg versus once-daily extended-release clarithromycin 500 mg in pediatric and adolescent patients

Clarithromycin is widely used to treat respiratory tract and superficial skin infections in pediatric and adult populations. Using clinical endpoints and 7-day therapy, we compared the efficacy of clarithromycin 250 mg tablets given twice daily versus clarithromycin 500 mg extendedrelease tablets given once daily in ambulatory children and adolescents 6 to 16 years old. Of the 199 evaluable patients, 124 were infected with group A streptococcal pharyngitis, 39 with sinusitis, 21 with ambulatory pneumonia, and 15 with superficial skin infections. The overall cure rate exceeded 90% for each treatment group. Discontinuation rates and adverse events were 4.5% and 24.6%, respectively.

Macrolide immunomodulatory effects and symptom resolution in acute exacerbation of chronic bronchitis and acute maxillary sinusitis: a focus on clarithromycin

Bacterial respiratory tract infections are common in the primary care setting and patients often seek the assistance of a healthcare professional in order to achieve resolution of their symptoms. Antibiotic agents that offer rapid symptom relief, in addition to excellent bacteriological and clinical cure, are highly desired. Macrolides have proven to be highly effective in treating acute bacterial exacerbations of chronic bronchitis and acute maxillary sinusitis. In addition, immunomodulatory effects that may contribute to symptom resolution have been reported. This article reviews current literature on symptom resolution in acute bacterial exacerbations of chronic bronchitis and acute maxillary sinusitis, with a focus on clarithromycin, and explores the potential mechanisms that may contribute to this action.