Cost-effectiveness of Gatifloxacin vs Ceftriaxone With a Macrolide for the Treatment of Community-Acquired Pneumonia

Comparative efficacy of azithromycin versus clarithromycin in combination with beta-lactams to treat community-acquired pneumonia in hospitalized patients: a systematic review

OBJECTIVE

The objective was to compare the efficacy of azithromycin and clarithromycin in combination with beta-lactams to treat community-acquired pneumonia among hospitalized adults.

METHODS

Five databases (PubMed, Google Scholar, Trip, Medline, and Clinical Key) were searched to identify randomized clinical trials with patients exposed to azithromycin or clarithromycin in combination with a beta-lactam. All articles were critically reviewed for inclusion in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Seven clinical trials were included. The treatment success rate for azithromycin-beta-lactam after 10 to 14 days was 87.55% and that for clarithromycin-beta-lactam after 5 to 7 days of therapy was 75.42%. Streptococcus pneumoniae was commonly found in macrolide groups, with 130 and 80 isolates in the clarithromycin-based and azithromycin-based groups, respectively. The length of hospital stay was an average of 8.45 days for patients receiving a beta-lactam-azithromycin combination and 7.25 days with a beta-lactam-clarithromycin combination.

CONCLUSION

Macrolide inter-class differences were noted, with a higher clinical success rate for azithromycin-based combinations. However, a shorter length of hospital stay was achieved with a clarithromycin-beta-lactam regimen. Thus, a macrolide combined with a beta-lactam should be chosen using susceptibility data from the treating facility.

Pneumococcal Disease: A Systematic Review of Health Utilities, Resource Use, Costs, and Economic Evaluations of Interventions

BACKGROUND

Pneumococcal diseases cause substantial mortality, morbidity, and economic burden. Evidence on data inputs for economic evaluations of interventions targeting pneumococcal disease is critical.

OBJECTIVES

To summarize evidence on resource use, costs, health utilities, and cost-effectiveness for pneumococcal disease and associated interventions to inform future economic analyses.

METHODS

We searched MEDLINE, Embase, Web of Science, CINAHL, PsycINFO, EconLit, and Cochrane databases for peer-reviewed studies in English on pneumococcal disease that reported health utilities using direct or indirect valuation methods, resource use, costs, or cost-effectiveness of intervention programs, and summarized the evidence descriptively.

RESULTS

We included 383 studies: 9 reporting health utilities, 131 resource use, 160 economic costs of pneumococcal disease, 95 both resource use and costs, and 178 economic evaluations of pneumococcal intervention programs. Health state utility values ranged from 0 to 1 for both meningitis and otitis media and from 0.3 to 0.7 for both pneumonia and sepsis. Hospitalization was shortest for otitis media (range: 0.1-5 days) and longest for sepsis/septicemia (6-48). The main categories of costs reported were drugs, hospitalization, and household or employer costs. Resource use was reported in hospital length of stay and number of contacts with general practitioners. Costs and resource use significantly varied among population ages, disease conditions, and settings. Current vaccination programs for both adults and children, antibiotic use and outreach programs to promote vaccination, early disease detection, and educational programs are cost-effective in most countries.

CONCLUSION

This study has generated a comprehensive repository of health economic evidence on pneumococcal disease that can be used to inform future economic evaluations of pneumococcal disease intervention programs.

Economic evaluation of community acquired pneumonia management strategies: A systematic review of literature

Background

Community-acquired pneumonia (CAP) is a major cause of mortality and morbidity worldwide. Efficient use of resources is fundamental for best use of money among the available and novel treatment options for the management of pneumonia. The objective of this study was to systematically review the economic analysis of management strategies of pneumonia.

Methods

A systematic search was performed using Academic Search Complete, MEDLINE, EconLit, Global health, MEDLINE complete and Embase databases using specific subject headings or key words in May 2018 without restricting publication year. All search results were recorded and any type of economic evaluation for management of CAP was included for detailed review. The Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist was used for quality appraisal.

Results

Nineteen studies met the inclusion criteria; ten studies were trial based, five conducted analysis using model based techniques and the rest of the studies were either based on observational, record review or pre-post intervention studies. Most of the studies conducted cost-effectiveness analysis (n = 15) and compared different combinations of antimicrobials. Most were based on developed countries (n = 17), considered adult age groups (n = 16) and used a provider perspective (n = 14). Nine studies reported dominant alternatives (lower cost with higher benefit). Sensitivity analysis was performed by the majority of studies (n = 15). Fourteen studies were assessed as either being excellent, very good or good quality, with no relationship found between publication year and study quality. Methodological variation, type of microbial used, perspective, costs and outcome measures limit the compatibility among the results of the included studies.

Conclusion

Economic evaluation of interventions for management of CAP to date supports cost-effectiveness of studied interventions. However, evidence relates largely to antimicrobials choice in older populations in developed countries. Parallel economic evaluation of different management strategies of CAP is recommended for both developed and developing countries to support rigorous and robust comparative economic analysis within health care systems.

PROSPERO registration no: CRD42018097174

Declining mortality among hospitalized patients with community-acquired pneumonia

Little information is available on the changes over time in community-acquired pneumonia (CAP) management and their impact on 30-day mortality in hospitalized patients. We performed a prospective, observational study of non-severely immunosuppressed hospitalized adults with CAP from 1995 to 2014. A total of 4558 patients were included. Thirty-day mortality decreased from 9.6% in the first study period (1995-99) to 4.1% in the last period (2010-14); with a progressive downward trend (-0.2% death/year; p for trend = 0.003). Over time, patients were older (p 0.02), had more co-morbidities (p 0.037), more frequently presented severe illness according to the Pneumonia Severity Index (p <0.001) and septic shock (p <0.001), and more often required intensive care unit admission (p <0.001). Combination antibiotic therapy (p <0.001) and fluoroquinolone use (p <0.001) increased. Factors independently associated with 30-day mortality were increasing age (OR 1.04; 95% CI 1.03-1.05), co-morbidities (OR 1.48; 95% CI 1.04-2.11), shock at admission (OR 4.95; 95% CI 3.49-7.00), respiratory failure (OR 1.89; 95% CI 1.42-2.52), bacteraemia (OR 2.16; 95% CI 1.58-2.96), Gram-negative bacilli aetiology (OR 4.79; 95% CI 2.52-9.10) and fluoroquinolone use (OR 0.45; 95% CI 0.29-0.71). When we adjusted for a propensity score to receive fluoroquinolones, the protective effect of fluoroquinolone use was not confirmed. In conclusion, 30-day mortality decreased significantly over time in hospitalized patients with CAP in spite of an upward trend in patient age and other factors associated with poor outcomes. Several changes in the management of CAP and a general improvement in global care over time may have caused the observed outcomes.

A retrospective analysis of practice patterns in the treatment of methicillin-resistant Staphylococcus aureus skin and soft tissue infections at three Canadian tertiary care centres

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) infections are increasingly being encountered and pose an increasing burden to the health care system in Canada.

OBJECTIVE

To elucidate and characterize the factors influencing the current MRSA treatment patterns in patients with skin and soft tissue infections (SSTIs) before linezolid became available on the Canadian market.

METHODS

A retrospective study collected demographic, treatment and resource use data on patients hospitalized at one of three geographically distinct tertiary care facilities, where MRSA SSTI treatment was initiated with intravenous (IV) vancomycin. Analysis of opportunities for IV-to-oral switch therapy was based on eligibility criteria.

RESULTS

Of 89 patients identified over a 43-month period, the mean (+/-SD) durations of anti-infective treatment and hospitalization were 22.4+/-21 days and 28.9+/-20.8 days, respectively. An infected surgical wound was most common, representing 62.9% of infections. The mean duration of vancomycin treatment was 19.5 days and the mean number of 1 g doses received was 29.0+/-32.9. The majority of patients (55.1%) initiated vancomycin therapy a mean of 5.4+/-8.9 days after confirmation of MRSA. Of the 70% of patients meeting criteria for IV-to-oral switch therapy, only 10% received oral treatment. The most common reason cited for not switching was lack of an effective oral alternative. Analysis of switch therapy criteria found that IV treatment continued for a mean of 13 days despite the appropriateness of the oral route.

CONCLUSIONS

Considerable variation exists in treatment patterns for MRSA infections. Improvements in the initiation of therapy and the use of IV-to-oral switch therapy may improve care and reduce the duration of hospitalization for MRSA SSTIs.

Current challenges in the management of the infected patient

PURPOSE OF REVIEW

Management of hospital-associated infections (HAIs) has been made more challenging by the increasing proportion of immunocompromised or otherwise severely ill patients and increasing prevalence of antibiotic-resistant pathogens in this environment. This review examines strategies to optimize clinical outcomes and lower healthcare costs for patients with HAIs by focusing on patient-related, pathogen-related, and drug-related factors.

RECENT FINDINGS

Factors have converged to increase the risk of infection with antibiotic-resistant pathogens in the current hospital environment, including the increasing prevalence of resistant species and number of hospitalized patients with conditions increasingly susceptible to infection with drug-resistant bacteria. Although the list of bacterial pathogens associated with HAIs has been fairly constant over time, the prevalence and resistance profile of these individual species continues to evolve. Periodic antibiograms should be utilized to access local patterns of resistance within the different hospital wards. Outcomes for patients with HAIs are optimized with early empiric treatment with an appropriate regimen, selected on the basis of patient characteristics and local resistance patterns. Dosing strategies should be utilized to ensure that the efficacy of an appropriate antibiotic is optimized, by achieving the pharmacodynamic target predictive of its efficacy. Using these strategies improves quality of care and is associated with lower overall healthcare costs.

SUMMARY

Bacterial resistance is an increasing problem in the hospital environment, and has been associated with poorer clinical outcomes and elevated healthcare costs. By using patient characteristics, local antibiograms, and dosing strategies to achieve an optimal pharmacodynamic profile, early appropriate empiric therapy can be utilized to improve clinical outcomes, minimize the development of resistance, and reduce healthcare costs.

Alvimopan use in laparoscopic and open bowel resections: clinical results in a large community hospital system

BACKGROUND

Alvimopan has received Food and Drug Administration approval to accelerate the time to upper and lower gastrointestinal recovery following partial large or small bowel resection with primary anastomosis.

OBJECTIVE

To assess the efficacy, safety, and economic benefit of alvimopan in patients undergoing open or laparoscopic bowel resection in a community hospital system setting.

METHODS

This 6-month, open-label, multi-hospital, prospective study combined with a retrospective chart review compared postoperative length of stay and postoperative ileus-related morbidity (nasogastric tube insertion, hospital readmission) for patients undergoing open or laparoscopic bowel resection who received alvimopan 12 mg (n = 108) versus historical control bowel resection patients (n = 91) who would have been eligible to receive alvimopan. Multivariate analysis assessed the effects of age and surgery type on postoperative length of stay. Additional-day hospital costs were estimated using ordinary least-squares regression to calculate costs based on length of stay in the control cohort.

RESULTS

Compared with historical controls, patients receiving alvimopan had a mean 1.8-day shorter postoperative length of stay (p = 0.01) and lower rates of nasogastric tube insertion (2% vs 15%, p < 0.001). Multivariate analysis revealed a statistically significant reduction in postoperative length of stay in the alvimopan group of approximately 1.2 days (p = 0.01), regardless of age or surgery type, with an even larger difference (3.2 days) observed in patients ≥70 years old. Mean cost savings associated with alvimopan use ranged from $531 (laparoscopic bowel resection) to $997 (open bowel resection) per patient.

CONCLUSIONS

Consistent with clinical trial data, alvimopan use resulted in an approximately 1 day shorter postoperative length of stay and was associated with substantial cost savings.

Health economics of use fluoroquinolones to treat patients with community-acquired pneumonia

Respiratory diseases account for approximately 10% of all hospital admissions in the United States. Pneumonia constitutes 35% of these cases, with an average length of stay (LOS) of 5.1 days. It is estimated that $8.4 billion to $10 billion of all annual US hospital expenditures are attributable to community-acquired pneumonia (CAP). As such, medical decisions, including empiric antibiotic choice, potentially exert an impact on hospital LOS and associated costs. In this review, we focus on the empiric antibiotic choices and associated costs of treatment for hospitalized patients with CAP, focusing on the use of fluoroquinolone therapy as recommended by the CAP guidelines.

A cost-minimisation analysis comparing different antibiotic regimens used in treating all-cause bacterial pneumonia in Hong Kong

BACKGROUND

To find out the antibiotic treatment regimens with the lowest cost for all-cause bacterial pneumonia, a study to compare the costs of different antibiotic regimens in the treatment of patients diagnosed with all-cause bacterial pneumonia who required hospitalisation was carried out.

METHODOLOGY

This was a multicentre, retrospective study of patient medical records. The primary aim was to examine whether the initial choice of antibiotic had affected the total cost of treatment, while the secondary aim was to find out whether the initial choice of antibiotic had affected the initial treatment failure rates and death rates. A cost-minimisation analysis (CMA) from a public hospital perspective was employed.

RESULTS

A total of 333 patient medical case notes were reviewed. The most commonly prescribed antibiotic regimen was amoxycillin-clavulanate (AC) followed by amoxycillin-clavulanate plus macrolide (ACM) and quinolone (Q). In the study population, no statistical significance could be detected between the mean cost of the three regimens. In the subgroup analysis of patients with a history of chronic obstructive pulmonary disease (COPD) and patients with a history of smoking, the Q regimen appeared to be the least expensive.

CONCLUSION

In the study population, no significant difference could be identified between the mean cost of the three antibiotic regimens. In a special populations such as patients with a history of COPD and patients with a history of smoking, the Q regimen appeared to be superior. Further studies in these areas are needed.

Review: Novel targets in the management of pneumonia

Community-acquired pneumonia (CAP) is the leading cause of death from infectious diseases in the US. It accounts each year for 500,000 hospitalizations and 45,000 deaths and represents one of the most common causes of intensive care unit (ICU) admission. The mortality rate due to severe CAP has shown little improvement in the past three decades, remaining between 21% and 58% in patients admitted to the intensive care unit. Antimicrobial agents are the cornerstone of therapy against CAP, but there are some novel antibiotic and nonantibiotic therapies that have been recently tested that may potentially impact outcomes of patients with severe CAP. We will review the most recent data regarding novel therapies in patients with the highest risk of death such as those with severe CAP.

The etiology of community-acquired pneumonia in Australia: why penicillin plus doxycycline or a macrolide is the most appropriate therapy

BACKGROUND

Available data on the etiology of community-acquired pneumonia (CAP) in Australia are very limited. Local treatment guidelines promote the use of combination therapy with agents such as penicillin or amoxycillin combined with either doxycycline or a macrolide.

METHODS

The Australian CAP Study (ACAPS) was a prospective, multicenter study of 885 episodes of CAP in which all patients underwent detailed assessment for bacterial and viral pathogens (cultures, urinary antigen testing, serological methods, and polymerase chain reaction). Antibiotic agents and relevant clinical outcomes were recorded.

RESULTS

The etiology was identified in 404 (45.6%) of 885 episodes, with the most frequent causes being Streptococcus pneumoniae (14%), Mycoplasma pneumoniae (9%), and respiratory viruses (15%; influenza, picornavirus, respiratory syncytial virus, parainfluenza virus, and adenovirus). Antibiotic-resistant pathogens were rare: only 5.4% of patients had an infection for which therapy with penicillin plus doxycycline would potentially fail. Concordance with local antibiotic recommendations was high (82.4%), with the most commonly prescribed regimens being a penicillin plus either doxycycline or a macrolide (55.8%) or ceftriaxone plus either doxycycline or a macrolide (36.8%). The 30-day mortality rate was 5.6% (50 of 885 episodes), and mechanical ventilation or vasopressor support were required in 94 episodes (10.6%). Outcomes were not compromised by receipt of narrower-spectrum beta-lactams, and they did not differ on the basis of whether a pathogen was identified.

CONCLUSIONS

The vast majority of patients with CAP can be treated successfully with narrow-spectrum beta-lactam treatment, such as penicillin combined with doxycycline or a macrolide. Greater use of such therapy could potentially reduce the emergence of antibiotic resistance among common bacterial pathogens.

Cost-effectiveness of oral gemifloxacin versus intravenous ceftriaxone followed by oral cefuroxime with/without a macrolide for the treatment of hospitalized patients with community-acquired pneumonia

We studied the cost-effectiveness of oral gemifloxacin with intravenous ceftriaxone followed by oral cefuroxime with or without a macrolide to treat patients hospitalized with community-acquired pneumonia. Data were prospectively collected as part of a randomized multicenter study. The costs evaluated included antimicrobial acquisition (1st level); plus preparation, dispensing, and administration costs, and treatment of antimicrobial-related adverse events and clinical failures (2nd level); plus per diem costs for hospital stay related to study drug administration (3rd level). At follow-up, clinical success was similar between gemifloxacin (76.9%)- and ceftriaxone (79.1%)-treated patients. The median 1st-level costs for gemifloxacin and ceftriaxone were $136 and $470 (P<0.001), respectively. For the 2nd level, these costs were $158 and $542 (P<0.001), and for the 3rd level, these were $5052 and $5789 (P=0.025), respectively. The median cost per expected success was $6568 for gemifloxacin and $7321 for ceftriaxone (P=0.29). Oral gemifloxacin is clinically effective and has an economic advantage over ceftriaxone, followed by oral cefuroxime with or without a macrolide.

Direct costs in patients hospitalised with community-acquired pneumonia after non-response to outpatient treatment with macrolide antibacterials in the US

INTRODUCTION

Antibacterial cost-containment programmes emphasise the use of narrow-spectrum generic agents whenever possible. The use of these agents is driven by their lower purchase prices; the consequences of treatment failure are rarely considered. This study was conducted to identify the costs of treating patients hospitalised with community-acquired pneumonia (CAP) associated with Streptococcus pneumoniae following failure to respond to outpatient treatment with macrolide antibacterials.

METHODS

A multicentre, retrospective, observational study was performed in patients with CAP due to S. pneumoniae who were admitted to 31 North American hospitals following a lack of response to >or=2 days of outpatient treatment with a macrolide antibacterial. Direct medical costs (year 2004 values) of infection-related hospital resources, including antibacterials (purchase, preparation, dispensing, administration and monitoring), diagnostic tests, therapeutic procedures, treatment of adverse events and therapeutic failures, and hospitalisation per diem (ward, critical care and ventilator days), were analysed. Total hospital costs were then compared with standard diagnosis-related group (DRG) reimbursement.

RESULTS

A total of 122 patients were enrolled. Patients were frequently bacteraemic (52%) and infected with macrolide-resistant strains of S. pneumoniae (71%). Initial inpatient antibacterial treatment was not successful in 17 patients (14%) and seven patients (5.7%) died. The mean length of stay was 8.7 days (SD 7) including 1.3 days (SD 2.9) in a critical care unit and 1.4 days (SD 4.4) of mechanical ventilation. The mean cost of hospitalisation was US dollars 12,678 (SD 13 346) but standard DRG reimbursement averaged only US dollars 8,634.

CONCLUSIONS

Patients who do not respond to outpatient treatment with a macrolide antibacterial and who are subsequently hospitalised with CAP caused by S. pneumoniae are likely to be infected with a non-susceptible strain, are frequently bacteraemic, are at an increased risk for mortality compared with previously published estimates in patients with CAP due to S. pneumoniae, and incur hospital costs that far exceed standard DRG reimbursement for CAP.

Community-Acquired Respiratory Complications in the Intensive Care Unit: Pneumonia and Acute Exacerbations of COPD

This chapter will review the two most common lower respiratory tract infections in the intensive care unit (ICU), community-acquired pneumonia (CAP) and acute exacerbations of chronic obstructive pulmonary disease (AECOPD). In addition we will provide an overview of the topics including recommendations for the diagnosis and treatment.

The role of new therapies for severe community-acquired pneumonia

PURPOSE OF REVIEW

Community-acquired pneumonia (CAP) is associated with significant morbidity and mortality and is the most common cause of death from infectious diseases. CAP patients requiring intensive care unit (ICU) admission carry the highest mortality rates. This paper aims to review the current literature regarding epidemiology, risk factors, severity criteria and reasons for admitting the hospitalized patient to the ICU, and the empiric and specific antibiotic therapeutic regimens employed.

RECENT FINDINGS

Multiple sets of clinical practice guidelines have been published in the past few years addressing the treatment of CAP. The guidelines all agree that CAP patients admitted to the hospital represent a major concern, and appropriate empiric therapy should be instituted to improve clinical outcomes.

SUMMARY

The cost, morbidity and mortality of CAP patients requiring ICU admission remain unacceptably high. These are heterogeneous groups of patients, so it is important to use risk-stratification based on clinical parameters and prediction tools. Appropriate antibiotic therapy is an important component in the management of both groups of patients. In particular, it is essential to administer an appropriate antimicrobial agent from the initiation of therapy, so that the risks of treatment failure and the morbidity of CAP may be minimized.

Resource utilization of adults admitted to a large urban hospital with community-acquired pneumonia caused by Streptococcus pneumoniae

OBJECTIVE

To determine if penicillin-nonsusceptible Streptococcus pneumoniae, among other variables, was significantly associated with greater hospital costs among patients with community-acquired pneumonia (CAP).

DESIGN

Retrospective, cohort study.

SETTING

Eight hundred ten-bed, urban, private, teaching hospital.

PATIENTS

Adult patients admitted between 1999 and 2003 with CAP caused by S pneumoniae.

INTERVENTION

Clinical criteria and costs (inflated to 2004 dollars) were collected from the medical charts and detailed hospital bills for each individual patient. Costs were compared according to classification by penicillin susceptibility. Multivariate linear regression was utilized to determine variables independently associated with increased hospital costs and length of stay.

RESULTS

Of 168 patients included, 44 patients (26%) had CAP caused by penicillin-nonsusceptible S pneumoniae. Median total hospital costs were 8,654 dollars (25th to 75th percentile, 5,457 dollars to 16,027 dollars), with no difference between susceptible and nonsusceptible groups. Bed costs accounted for 55.6% of total costs, followed by laboratory (9.9%) and pharmacy (9.8%) costs. Regression analyses determined that ICU admission (p < 0.001), unexplained delays in discharge (p = 0.001), and neoplasm (p < 0.04) were independently predictive of both total hospital costs (adjusted r2 = 0.46) and increasing length of stay (adjusted r2 = 0.30). Hospital mortality, bacteremia, and congestive heart failure were also associated with at least one of the dependent variables.

CONCLUSION

In the current era in which more potent antibiotics are empirically utilized to treat CAP, it does not appear that a simple classification of penicillin nonsusceptibility complicates the economic impact of S pneumoniae infection. Focused efforts to reduce length of stay, including minimizing prolonged and unnecessary observation of patients, should have the most profound effect on reducing total costs.

Pharmacoeconomic considerations associated with the use of intravenous-to-oral moxifloxacin for community-acquired pneumonia

BACKGROUND

Intravenous-to-oral (iv/po) conversion is one cost-effective approach to the management of community-acquired pneumonia (CAP).

METHODS

Consecutive patients with CAP were enrolled during 3 study periods (January-March of 2001, 2002, and 2004) with different pharmacy intervention (PI) strategies: iv beta -lactam plus a macrolide (no PI), iv beta-lactam plus a macrolide with iv/po PI (PI switch), and iv moxifloxacin with pharmacist-initiated automatic po moxifloxacin conversion (PI sequential). Costs and outcomes were compared among groups.

RESULTS

Two hundred fifty-one patients were enrolled. The average Fine score was 75, and the mean age of patients was 51 years. In the PI groups, the duration of treatment with iv antibiotics was decreased. Clinical success on day 3 of therapy was improved in the PI sequential group but was similar in all 3 groups on day 7 of therapy and at the end of therapy. The length of stay in the hospital was similar for patients in all 3 groups (mean, 4.39 days). Antibiotic costs were significantly reduced, by $110/patient, in the PI sequential group.

CONCLUSIONS

Conversion from iv to po therapy was accomplished more quickly when converting to the same agent with pharmacist-initiated automatic iv/po conversion, thus reducing the associated cost without compromising efficacy.

Pharmacoeconomics of treatment with the newer anti-Gram-positive agents

The unmet medical need of emerging resistance among Gram-positive pathogens, such as methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci and penicillin-resistant Streptococcus pneumoniae, has driven industry towards the identification and development of novel anti-Gram-positive agents. Among the newer agents are improved quinolones, a lipopeptide, an oxazolidinone and novel glycopeptides. Scientific distinctions between these drugs, which impact on the placement, usage and, ultimately, the pharmacoeconomics of several of these new agents, may lead to further consideration despite poor initial observations of minimal improvement. Key differences in the characteristics of these drugs (i.e., spectrum, activity, resistance emergence, efficacy, target, safety) provide a basis for an emerging pharmacoeconomic-based distinction between these newer anti-Gram-positive agents.

Optimal pharmacological therapy for community-acquired pneumonia: the role of dual antibacterial therapy

The optimal pharmacological therapy of community-acquired pneumonia (CAP) is one of the most ardently debated issues in medicine. Presently, most guidelines recommend either a fluoroquinolone alone or dual therapy with a third-generation cephalosporin plus a macrolide in patients hospitalised with CAP, but few provide clinicians with specific considerations for selecting from these agents. Despite a similar spectrum of activity and favourable resistance patterns (for fluoroquinolones and third-generation cephalosporins) against CAP pathogens, there is emerging evidence that dual therapy may be superior to monotherapy in certain populations.In patients with non-severe CAP, the evidence supports the use of either monotherapy or dual therapy in most patients; however, patients with severe CAP or bacteraemic pneumococcal CAP experience improved survival when treated with dual therapy. It is unclear from this evidence if any specific combination of agents is the most effective, but the combination of a third-generation cephalosporin plus a macrolide is the most extensively studied. Dual therapy was superior to monotherapy irrespective of the susceptibility of the aetiological pathogen, thus insufficient antimicrobial spectrum does not explain the disparity. The most likely explanation for improved outcomes with dual therapy is the combined effect of optimised antimicrobial spectrum (including atypicals), decreased impact of resistance to a single agent and the immunomodulatory effects of macrolides. Increasing resistance in patients with non-severe CAP warrants the consideration of dual therapy and perhaps a reappraisal of agents usually reserved for second-line therapy, including doxycycline, in these populations as well. In light of the available evidence, dual therapy should be strongly considered in all patients with severe CAP, especially when complicated by pneumococcal bacteraemia.

Highlights on the appropriate use of fluoroquinolones in respiratory tract infections

The impact of respiratory infections on public health is increasing, and lower respiratory tract infections are a major cause of morbidity and mortality. Moreover, most antibiotic prescriptions are related to respiratory infections and this is probably one of the main determinants of the increasing rate of bacterial resistance in both community and hospital settings. This has been the catalyst for the development of new drugs, such as the new fluoroquinolones. The new fluoroquinolones have an excellent spectrum providing cover for the most important respiratory pathogens, including atypical and "typical" pathogens. The pharmacokinetic and dynamic properties of the new fluoroquinolones have a significant impact on their clinical and bacteriological efficacy. They cause a concentration-dependent killing with a sustained post-antibiotic effect. Fluoroquinolones combine exceptional efficacy with cost-effectiveness. Not surprisingly, different guidelines have inserted these agents among the drugs of choice in the empirical therapy of LRTIs. This review discusses the most recent data on the bacteriological and clinical activity of the new fluoroquinolones and critically analyses the risks of a potential overuse of this valuable new class of drugs.

A cost-minimization analysis comparing azithromycin-based and levofloxacin-based protocols for the treatment of patients hospitalized with community-acquired pneumonia: results from the CAP-IN trial

BACKGROUND

A randomized trial was performed comparing azithromycin and levofloxacin for treating moderately to severely ill patients hospitalized with community-acquired pneumonia. This is a cost-minimization analysis comparing those regimens.

METHODS

The cost-minimization analysis compares 81 patients receiving sequential therapy with IV azithromycin plus IV ceftriaxone followed by oral azithromycin with 82 patients receiving IV levofloxacin followed by oral levofloxacin, all with complete economic data over approximately 30 days, including information about hospitalization, study medications, home care, postdischarge utilization, and lost productivity. Units of utilization were multiplied by unit prices in order to estimate cost per patient. These total costs were compared using a two-sample t test.

RESULTS

Direct medical costs of the azithromycin group were 2,481 US dollars less than the corresponding costs in the levofloxacin group (p = 0.03; 95% confidence interval, 238 US dollars to 4,724 US dollars). Most of the cost difference (2,300 US dollars) is attributable to hospital days, with the majority of these days being spent on the general medicine wards. The precise magnitude of the cost advantage attributable to azithromycin, if any, depends on both the reduction in length of hospital stay and its associated daily cost.

CONCLUSIONS

Azithromycin was no more costly than levofloxacin, and perhaps less so. Cost is but one of many factors that should be considered by clinicians in decisions involving any individual patient.

Gemifloxacin for the treatment of respiratory tract infections: in vitro susceptibility, pharmacokinetics and pharmacodynamics, clinical efficacy, and safety

Gemifloxacin is a synthetic fluoroquinolone antimicrobial agent exhibiting potent activity against most gram-negative and gram-positive organisms, such as the important community-acquired respiratory pathogens Streptococcus pneumoniae (including multidrug-resistant S. pneumoniae), Haemophilus influenzae , and Moraxella catarrhalis . The agent's mechanism of action involves dual targeting of two essential bacterial enzymes: DNA gyrase and topoisomerase IV. Gemifloxacin was approved by the Food and Drug Administration in April 2003 for treatment of community-acquired pneumonia and acute bacterial exacerbation of chronic bronchitis. The drug has an oral bioavailability of approximately 71%. Approximately 20-35% of gemifloxacin is excreted unchanged in the urine after 24 hours. The elimination half-life of gemifloxacin is 6-8 hours in patients with normal renal function, supporting once-daily dosing. The 24-hour free-drug area under the plasma concentration-time curve:minimum inhibitory concentration ratio (fAUC(0-24):MIC) associated with efficacy, based on results from in vitro and animal models of infection, is approximately 30. With a mean fAUC(0-24) of approximately 3 microg*hour/ml (35% of total AUC(0-24) of 8.4) and a median S. pneumoniae MIC for 90% of tested strains of 0.03, a fAUC(0-24):MIC ratio of 100 would be expected after standard dosing (320 mg once/day). In clinical studies involving both hospitalized and outpatient populations, gemifloxacin has been highly effective in the treatment of community-acquired pneumonia and acute exacerbation of chronic bronchitis. Clinical success rates ranged from 93.9-95.9% in patients with community-acquired pneumonia and 96.1-97.5% in those with acute exacerbation of chronic bronchitis. Gemifloxacin is well tolerated; the frequency of adverse events with this agent is low. Most adverse events are mild-to-moderate in severity, with diarrhea (< 4%), nausea and rash (< 3%), and headache (< 2%) most commonly reported. Drug interactions with gemifloxacin are not common, although absorption is greatly reduced when given with divalent and trivalent cation-containing compounds, such as antacids. Due to its potent activity against many common gram-positive and gram-negative respiratory pathogens, its proven clinical efficacy, and its favorable safety profile, gemifloxacin is a highly effective empiric treatment for community-acquired lower respiratory tract infections.

The Controversy of Combination vs Monotherapy in the Treatment of Hospitalized Community-Acquired Pneumonia

BACKGROUND

The majority of community-acquired pneumonia (CAP) patients (about 80%) will be treated as outpatients, because therapy with a single agent will work. For the remaining 20% of patients requiring hospitalization, there is some growing debate regarding the efficacy of different management approaches. For hospitalized patients, monotherapy with a respiratory fluoroquinolone agent seems to be gaining popularity, but dual therapy combining a beta-lactam and an advanced macrolide still represents a good choice. Indeed, this regimen was recommended for all of the inpatient categories in the latest Infectious Disease Society of America CAP guidelines in 2003.

AIM

The purpose of this review was to examine the current clinical evidence to support one option or the other by gathering all of the available published literature. We will review the existing controversies in terms of microbiology, immunology, and clinical outcomes comparing dual therapy (ie, with any combination of beta-lactams, macrolides, or fluoroquinolones) with monotherapy in the treatment of CAP.

RESULTS

For the vast majority of patients with CAP (ie, outpatients and inpatients on medical wards), the type of antibiotic regimen prescribed does not have any significant impact. For patients with severe pneumonia, for which there is no accepted definition so far, the controversy remains alive. Mortality from pneumococcal pneumonia has been reduced over the last decades, but despite improved medical care, bacteremic pneumococcal pneumonia is still as lethal as ever, probably because of the aging population, the greater number of immunocompromised patients, and the number of patients with frequent comorbid conditions. Worldwide, the increasing rates of resistance of Streptococcus pneumoniae to antibiotics are also a serious concern, and the clinical implications are not always obvious. Although limited in number, the four studies showing the importance of adding a macrolide to a beta-lactam regimen for the treatment of bacteremic S pneumoniae pneumonia are retrospective and nonblinded, the findings are consistent, and they point to a trend that has to be explored more thoroughly. Studies published in the last few years suggest that combination therapy may be superior for bacteremic S pneumoniae pneumonia.

CONCLUSION

In the meantime, for practical purposes, patients hospitalized with a diagnosis of severe CAP may benefit from a dual antibiotic therapy combining a third-generation cephalosporin and a macrolide. For the majority of hospitalized patients with CAP who are not severely ill, fluoroquinolone monotherapy remains an approved, tested, and reliable option. Indeed, the time for more aggressive outpatient fluoroquinolone therapy may reduce the number of patients who are hospitalized with CAP. Independent prospective studies comparing combination therapy with standard monotherapy are urgently required for hospitalized patients with severe CAP.

Antimicrobial treatment of community-acquired pneumonia

Community-acquired pneumonia (CAP) is a clinical diagnosis that has a significant impact on health care management around the world. Early clinical suspicion and prompt empiric antimicrobial therapies are mandatory in patients with CAP. This article provides a review of recent studies and guidelines addressing antimicrobial therapy for hospitalized patients with CAP.

Monotherapy versus combination antimicrobial therapy for pneumococcal pneumonia

PURPOSE OF REVIEW

In the past 5 years a number of studies have suggested that combination antibiotic therapy may be superior to monotherapy for pneumococcal pneumonia. This review outlines the major findings for and against combination therapy.

RECENT FINDINGS

The evidence for a benefit of multiple antibiotics is strongest in patients with severe, bacteremic pneumococcal disease. All of these studies have limitations due to their retrospective or uncontrolled design. Unfortunately prospective, randomized, double-blind, controlled studies have not been performed in an appropriately severe disease cohort and are therefore urgently needed. Several viable mechanisms for a benefit of combination therapy have been proposed, especially related to non-antibiotic effects of macrolides. There is also some evidence that third-generation cephalosporins may be superior to penicillins as the non-macrolide component of combination therapy.

SUMMARY

Although based on retrospective and observational data, there is substantial evidence to support combination antibiotic therapy, at least in patients with severe bacteremic pneumococcal pneumonia. What evidence is available supports a cephalosporin/macrolide combination as being associated with the highest survival, but proper prospective studies in patients with severe pneumonia are urgently required to clarify this issue.

Economics of antibiotic use policies

Today more than ever, hospitals must effectively manage the use of antibiotics to control costs and preserve their usefulness. To achieve this goal, antibiotic management must evolve from overly simplistic antibiotic cost containment to more complex, multidisciplinary, appropriate use programs that are founded on clinical outcomes-based pharmacoeconomic analyses. This article addresses common cost-containment activities as they relate to antibiotics and examines their consequences. Examples of successful antimicrobial stewardship and the role of pharmacoeconomic analyses also are provided. Cost-effectiveness studies of cefepime are presented to illustrate the utility of these analyses and provide information that can form the basis for decisions regarding placement of cefepime on hospital formularies.

The cost of glucocorticoid-associated adverse events in rheumatoid arthritis

OBJECTIVE

To estimate the costs of glucocorticoid associated adverse events (GAEs) in patients with rheumatoid arthritis (RA).

METHODS

We conducted a literature review of studies reporting GAEs in RA patients, and developed a Markov model with the following GAEs: fractures (vertebral, hip, pelvic), hypertension, diabetes, gastrointestinal complications, pneumonia, urinary tract infection, cataract and, in an extended model, myocardial infarction (MI) and stroke. Two-year total costs were calculated using direct medical costs (2001 US dollars [USD]) and by running 10,000 Monte Carlo simulations with probability values randomly selected from the GAE literature.

RESULTS

On average, glucocorticoid users spent USD 445 more than non-users, or USD 0.46 for each dollar spent on purchasing the drug. When adding MI and stroke, users spent on average USD 430 more than non-users, or USD 0.44 for each dollar spent on purchasing the drug; this incremental cost ranged from USD 193 to USD 682 if MI and stroke were excluded, respectively. In 70% of the simulations there were more deaths among users than among non-users, in both the model with and without MI and stroke.

CONCLUSIONS

Although results varied depending on attributed GAEs, in general glucocorticoid users spent more than non-users on GAE treatment, and had higher mortality. Patients, providers and policy makers should consider these potential costs of GAEs when making treatment decisions.

Community-acquired pneumonia: new management strategies for evolving pathogens and antimicrobial susceptibilities

Community-acquired pneumonia (CAP) is still one of the leading causes of mortality and morbidity. The most common bacterial cause of CAP is Streptococcus pneumoniae. The increase in antimicrobial resistance has raised concerns about the efficacy of available therapies, and a call for the reassessment of both existing and newer therapeutic agents. Although microbiological breakpoints are useful for monitoring the emergence of resistance, the current National Committee for Clinical Laboratory Standards (NCCLS) guidelines make no distinction between clinical and microbiological breakpoints. Recent changes in NCCLS breakpoints for extended spectrum cephalosporins have provided a more meaningful approach to susceptibility testing and to consideration of the site of infection. Further controversy surrounds the clinical guidelines relating to CAP in terms of which antimicrobial agents should be given empirically to which types of patients. Within this review, the role of monotherapy versus the need for combination antimicrobial therapy, which often includes a macrolide and an extended spectrum cephalosporin such as ceftriaxone, is discussed. This review also discusses the various aspects of antimicrobial susceptibilities of S. pneumoniae, the drivers and influences of increasing resistance, the clinical relevance of this resistance and possible therapeutic options in the face of changing susceptibilities and mixed bacterial aetiologies. New guidelines from the IDSA attempt to embrace these changes.

The costs and consequences of methicillin-resistant Staphylococcus aureus infection treatments in Canada

BACKGROUND

A multinational randomized controlled trial has shown a trend toward early discharge of patients taking oral linezolid versus intravenous vancomycin (IV) in the treatment of methicillinresistant Staphylococcus aureus (MRSA) infections. Infection treatments resulting in shorter hospitalization durations are associated with cost savings from the hospital perspective.

OBJECTIVE

To determine whether similar economic advantages are associated with oral linezolid, the costs and consequences of linezolid use following vancomycin IV versus the existing practice in the treatment of infections caused by MRSA were compared.

METHODS

The charts of all patients admitted to one of three tertiary care teaching hospitals between January 1, 1997 and August 31, 2000 and treated with vancomycin IV for an active MRSA infection (skin and soft tissue only) were reviewed. Based on the vancomycin IV chart review data set and a simulated linezolid data set, the clinical consequences and the associated costs of MRSA treatment with vancomycin IV, and oral and IV forms of linezolid were quantified and compared within the framework of a cost-consequence analysis.

RESULTS

Patients treated with oral and IV forms of linezolid compared with the existing practice had a shorter length of stay and required fewer home IV care services, which resulted in a cost savings of $750 (2001 values) to the Canadian health care perspective.

CONCLUSIONS

The estimated cost savings associated with linezolid use not only offset the higher acquisition cost of the anti-infective, but may be substantial to health care systems across Canada, especially as the incidence of MRSA continues to rise.

Monotherapy versus Dual Therapy for Community-Acquired Pneumonia in Hospitalized Patients

Several medical-specialty professional societies have suggested that combination therapy with a beta -lactam plus a macrolide or doxycycline or monotherapy with a "respiratory quinolone" (i.e., levofloxacin, gatifloxacin, moxifloxacin, or gemifloxacin) are optimal first-line therapy for patients hospitalized with community-acquired pneumonia. These recommendations are based predominantly on retrospective studies that suggest improved rates of morbidity and mortality and hospital length of stay among patients treated in such a fashion. Well-designed, prospective, randomized studies confirming this tenet of therapy have not been published, although numerous prospective studies have provided indirect confirmation. The biological rationale for such a differential response (i.e., favoring combination therapy or fluoroquinolone therapy) includes the immunomodulatory effects of macrolides or more-optimal treatment of primary infection or coinfection with atypical pathogens. Well-designed, prospective, randomized trials are required to best define the effectiveness of combination therapy with a beta -lactam plus macrolide or doxycycline or with a respiratory quinolone in hospitalized patients with community-acquired pneumonia.

Linezolid for treatment of ventilator-associated pneumonia: A cost-effective alternative to vancomycin*

OBJECTIVES

To determine the incremental cost-effectiveness of linezolid compared with vancomycin for treatment of ventilator-associated pneumonia due to Staphylococcus aureus.

DESIGN

Decision model analysis of the cost and efficacy of linezolid vs. vancomycin for treatment of ventilator-associated pneumonia. The primary outcome was the incremental cost-effectiveness of linezolid in terms of cost per added quality-adjusted life-year gained. Other outcomes were the marginal costs per hospital survivor and per year of life saved generated by using linezolid. Model estimates were derived from prospective trials of linezolid for ventilator-associated pneumonia and from other studies describing the costs and outcomes for ventilator-associated pneumonia.

SETTING AND PATIENTS

Hypothetical cohort of 1,000 patients diagnosed with ventilator-associated pneumonia.

INTERVENTIONS

In the model, patients received either linezolid or vancomycin.

MEASUREMENTS AND MAIN RESULTS

The incremental cost-effectiveness of linezolid was calculated as the additional quality-adjusted life-years resulting from therapy with linezolid divided by the sum of the incremental costs arising because of use of linezolid (e.g., higher direct costs for linezolid, costs per in-hospital care of survivors, and posthospitalization costs). Despite its higher cost, linezolid was cost-effective for treatment of ventilator-associated pneumonia. The cost per quality-adjusted life-year equals approximately 30,000 dollars. The model was moderately sensitive to the estimated efficacy of linezolid over vancomycin. Nonetheless, even with all inputs simultaneously skewed against, linezolid remains a cost-effective option (cost per quality-adjusted life-year approximately 100,000 dollars). Based on Monte Carlo simulation, the results of our analysis are robust across a range of model inputs and assumptions (95% confidence interval for cost per quality-adjusted life-year ranges from 23,637 dollars to 42,785 dollars).

CONCLUSIONS

Linezolid is a cost-effective alternative to vancomycin for the treatment of ventilator-associated pneumonia.

Economic aspects of pneumococcal pneumonia: a review of the literature

In this review, the economic aspects of pneumococcal pneumonia are analysed, including the costs, cost effectiveness and cost benefit of treatment and prevention. We identified eight cost-of-illness studies, 15 analyses comparing the costs of different treatment options and 15 economic evaluations of prevention that met our search criteria. The studies were conducted largely in Europe and the US. Most pertained to community-acquired pneumonia (CAP) in general, without specific analysis of pneumococcus-related illness. Many of the studies were considered to be of poor quality for the following reasons: comparison without randomisation or control variables, disregard of health outcomes, small sample size, restriction of costs to drug costs and vague or disputable sources of cost information. In the US, hospitalisation costs resulting from CAP can be estimated to be between US 7,000 dollars and US 8,000 dollars per admission or US 4 million dollars per 100,000 population. Hospitalisation costs are significant (representing about 90% of total costs), but are much lower in Europe than in the US (one-third to one-ninth of the US estimates in the UK and Spain, respectively). In general, economic studies of treatment for pneumococcal pneumonia are in line with clinical evidence. A drug with proven clinical effectiveness would also appear to be supported from an economic stand point. Furthermore, economic data support an early switch from an intravenous to an oral antibacterial, the use of quinolones for inpatients with CAP, and also the use of guidelines built on clinical evidence. Of all the possible preventive strategies for pneumococcal pneumonia, only vaccination has been subjected to economic evaluation. Pneumococcal polysaccharide vaccine seems relatively cost effective (and potentially cost saving) for those between 65 and 75 years of age, for military recruits and for HIV positive patients with a sufficiently high CD4 cell count. Evaluations of the pneumococcal conjugate vaccine (PCV) indicate the price of the vaccine to be the main determinant of cost effectiveness. As the current price is high (in the order of US 50 dollars per dose), the economic attractiveness of the universal PCV vaccination strategies hinges on the potential for price reductions and the willingness of decision makers to adopt a societal perspective.

Economic aspects of severe sepsis: a review of intensive care unit costs, cost of illness and cost effectiveness of therapy

Severe sepsis remains both an important clinical challenge and an economic burden in intensive care. An estimated 750,000 cases occur each year in the US alone (300 cases per 100,000 population). Lower numbers are estimated for most European countries (e.g. Germany and Austria: 54-116 cases per year per 100,000). Sepsis patients are generally treated in intensive care units (ICUs) where close supervision and intensive care treatment by a competent team with adequate equipment can be provided. Staffing costs represent from 40% to >60% of the total ICU budget. Because of the high proportion of fixed costs in ICU treatment, the total cost of ICU care is mainly dependent on the length of ICU stay (ICU-LOS). The average total cost per ICU day is estimated at approximately 1200 Euro for countries with a highly developed healthcare system (based on various studies conducted between 1989 and 2001 and converted at 2003 currency rates). Patients with infections and severe sepsis require a prolonged ICU-LOS, resulting in higher costs of treatment compared with other ICU patients. US cost-of-illness studies focusing on direct costs per sepsis patient have yielded estimates of 34,000 Euro, whereas European studies have given lower cost estimates, ranging from 23,000 Euro to 29,000 Euro. Direct costs, however, make up only about 20-30% of the cost of illness of severe sepsis. Indirect costs associated with severe sepsis account for 70-80% of costs and arise mainly from productivity losses due to mortality. Because of increasing healthcare cost pressures worldwide, economic issues have become important for the introduction of new innovations. This is evident when introducing new biotechnology products, such as drotrecogin-alpha (activated protein C), into specific therapy for severe sepsis. Data so far suggest that when drotrecogin-alpha treatment is targeted to those patients most likely to achieve the greatest benefit, the drug is cost effective by the standards of other well accepted life-saving interventions.

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.

Evaluation of outcomes in community-acquired pneumonia: a guide for patients, physicians, and policy-makers

Community-acquired pneumonia (CAP) is a key target for research and quality improvement in acute medicine. However, many of the outcome measures used in prognostic and antibiotic studies are not validated and do not capture features of outcome that are important to patients. Substitutes for traditional outcome measures include a recently validated patient-based symptom questionnaire (the CAP-Sym) and process-of-care measures. The interpretation of outcomes also depends on the quality of the study design and methods used. This paper discusses the advantages and disadvantages of outcome, process-of-care, and economic measures in CAP and the interpretation of these measures in randomised and observational studies. A core set of measures for use in clinical CAP research and performance measurement is proposed.

Therapeutic potential of the new quinolones in the treatment of lower respiratory tract infections

The impact of respiratory infections on public health is increasing and lower respiratory tract infections are a major cause of morbidity and mortality. We are also facing a worldwide burst of antibiotic bacterial resistance. The new fluoroquinolones have an excellent spectrum covering the most important respiratory pathogens, including atypical and 'typical' pathogens. Pharmacokinetic and dynamic properties of the new fluoroquinolones have a significant impact on their clinical and bacteriological efficacy. They cause a concentration-dependent killing with a sustained postantibiotic effect. Fluoroquinolones combine exceptional efficacy with cost-effectiveness. Not surprisingly, different guidelines have inserted these agents among the drugs of choice in the empirical therapy of community-acquired pneumonia. This review discusses the more recent data on bacteriological and clinical activity and critically analyses the risks of a potential overuse of this valuable new class of drugs.

A novel method of estimating cost of therapy by using patient population characteristics: analysis of fluoroquinolones in various populations with different distributions of renal function

INTRODUCTION

Formulary decisions regarding a given drug class are often made in the absence of patient outcome and/or sophisticated pharmacoeconomic data. Analyses that consider factors beyond simple acquisition costs may be useful in such situations. For example, the cost implications of using manufacturers' recommendations for dosing in patients with renal dysfunction may be important, depending on the distribution of various levels of renal function within a patient population.

METHODS

Using four 1000-patient populations representing different renal function distributions and a fifth population of our medical center's distribution, we determined the costs of therapy for intravenous and oral levofloxacin, gatifloxacin, and moxifloxacin for a 10-day course of therapy for community-acquired pneumonia. Costs considered were average wholesale prices (AWPs), 50% of AWP, or same daily price, plus intravenous dose preparation and administration costs when applicable. Costs for each renal function distribution were examined for significant differences with an analysis-of-variance test. Also, costs of failing to adjust dosing regimens for decreased renal function were determined.

RESULTS

Differences in fluoroquinolone costs (AWP, 50% AWP, or when matched as the same daily price) among the populations were found. When considering same daily prices, differences among populations ranged from about 35,000 dollars with intravenous gatifloxacin to more than 51,000 dollars for intravenous levofloxacin (all fluoroquinolones, p>0.05). Within a population, differences in costs among the intravenous fluoroquinolones ranged from 47,000-99,000 dollars. Rank orders of the drugs and population costs of therapy were affected by the pricing structure used and varied by the specific population and drug. Differences among the fluoroquinolones or populations were much smaller (<2100 dollars) when considering oral regimens. Costs potentially incurred by failing to adjust dosing for renal function were substantial.

CONCLUSION

Formulary decisions can be facilitated by considering factors such as patient characteristics and related dosing in addition to simple acquisition costs. In our example, consideration of the distribution of renal function within a given patient population and related dosing for these fluoroquinolones revealed potentially important differences within the class.

Oral gemifloxacin versus sequential therapy with intravenous ceftriaxone/oral cefuroxime with or without a macrolide in the treatment of patients hospitalized with community-acquired pneumonia: a randomized, open-label, multicenter study of clinical efficacy and tolerability

OBJECTIVE

This study aimed to compare the efficacy and safety of oral gemifloxacin, an enhanced-affinity quinolone, with sequential therapy with IV ceftriaxone followed by oral cefuroxime (with or without a macrolide) in patients hospitalized for community-acquired pneumonia (CAP).

METHODS

A randomized, open-label, multicenter study comprised adults hospitalized with a clinical and radiologic diagnosis of CAP. Patients were randomized 1:1 to receive either (1) oral gemifloxacin 320 mg once daily (7-14 days); or (2) IV ceftriaxone 2 g once daily (1-7 days) followed by oral cefuroxime 500 mg twice daily (1-13 days) for a total of < or = 14 days. Patients receiving ceftriaxone/cefuroxime were allowed concomitant macrolide treatment.

RESULTS

A total of 345 patients were randomized, of whom 341 received at least 1 dose of study medication (gemifloxacin, 169/172; ceftriaxone/cefuroxime, 172/173). Clinical success rates in the clinically evaluable (CE) population at follow-up (day 21-28 post-therapy), the primary end point, were 92.2% (107/116) for gemifloxacin and 93.4% (113/121) for ceftriaxone/cefuroxime (treatment difference, -1.15; 95% CI, -7.73 to 5.43). In patients in Fine risk classes IV and V, the clinical success rate was 87.0% (20/23) for gemifloxacin versus 83.3% (20/24) for ceftriaxone/cefuroxime. No difference in clinical response at follow-up was noted based on macrolide use. Bacteriologic success rates at follow-up in the bacteriologically evaluable (BE) population were 90.6% (58/64) for gemifloxacin and 87.3% (55/63) for ceftriaxone/cefuroxime (treatment difference 3.32; 95% CI, -7.57 to 14.21). The clinical success rate in bacteremic patients at follow-up (BE population) was 100.0%. Both treatments were generally well tolerated. The frequency and types of adverse events were similar between the 2 groups. The most common treatment-related adverse events with gemifloxacin were diarrhea, liver-function adverse events, and rash; with ceftriaxone/cefuroxime, they were diarrhea, elevated hepatic-enzyme activity, and moniliasis.

CONCLUSION

The clinical efficacy and tolerability of oral gemifloxacin 320 mg once daily were similar to those of IV ceftriaxone followed by oral cefuroxime (with or without a macrolide) in the treatment of adult patients hospitalized with moderate to severe CAP. Both treatments were effective in bacteremic patients and those at increased risk of mortality.

Cost-effectiveness of IV-to-oral switch therapy: azithromycin vs cefuroxime with or without erythromycin for the treatment of community-acquired pneumonia

STUDY OBJECTIVE

To conduct a cost-effectiveness analysis of IV-to-oral regimens of azithromycin vs cefuroxime with or without erythromycin in the treatment of patients hospitalized with community-acquired pneumonia (CAP).

PATIENTS

Of the 268 evaluable patients enrolled into a randomized, multicenter clinical trial of adults, 266 patients had sufficient data to be included in this cost-effectiveness analysis. One hundred thirty-six patients received azithromycin, and 130 patients received cefuroxime with or without erythromycin.

METHODS

A pharmacoeconomic analysis from the hospital provider perspective was conducted. Health-care resource utilization was extracted from the clinical database and converted to national reference costs. Decision analysis was used to structure and characterize outcomes. Sensitivity analyses were performed, and statistics were applied to the cost-effectiveness ratios.

RESULTS

The clinical success and adverse event rates and antibiotic-related length of stay were 78%, 11.8%, and 5.8 days for the azithromycin group and 75%, 20.7%, and 6.4 days for the group receiving cefuroxime with or without erythromycin, respectively. Geometric mean treatment costs were 4,104 US dollars (95% confidence interval [CI], 3,874 to 4,334 US dollars) for the azithromycin group, and 4,578 US dollars (95% CI, 4,319 to 4,837 US dollars) for the group receiving cefuroxime with or without erythromycin (p = 0.06). The cost-effectiveness ratios were 5,265 US dollars per expected cure for the azithromycin group, and 6,145 US dollars per expected cure for group receiving cefuroxime with or without erythromycin (p = 0.05).

CONCLUSIONS

Despite a higher per-dose purchase price, overall costs with azithromycin tended to be lower due to decreased duration of therapy, lower preparation and administration costs, and reduced hospital length of stay. As empiric therapy, azithromycin monotherapy was cost-effective compared to cefuroxime with or without erythromycin for patients hospitalized with CAP who have no underlying cardiopulmonary disease, and no risk factors for either drug-resistant pneumococci or enteric Gram-negative pathogens.

Evaluation and cost assessment of fluoroquinolones in community-acquired respiratory infections

Several new fluoroquinolones have been marketed since the late 1990s. Fluoroquinolones are an effective treatment for most community-acquired respiratory tract infections, including acute sinusitis, acute exacerbations of chronic bronchitis and community-acquired pneumonia. However, other antibiotics, including beta-lactams, macrolides, tetracyclines and trimethoprim-sulfamethoxazole, are also effective against these respiratory infections. From a managed care perspective, it is the subtle differences between the drugs in the eradication of bacterial pathogens, adverse effects, dose regimens, compliance issues, bacterial resistance and cost that determine the best choice for the management of pneumonia, sinusitis or exacerbations of chronic bronchitis. The potential for bacterial resistance is perhaps the only significant barrier to extensive fluoroquinolone use in community-acquired respiratory tract infections. Cost-effectiveness must be balanced with quality care, both from an individual perspective and that of the greater society.

IV-to-oral switch therapy for community-acquired pneumonia requiring hospitalization: focus on gatifloxacin

The majority of the 1.1 million patients hospitalized for community-acquired pneumonia (CAP) in the United States begin therapy with an intravenous antibiotic. A switch to oral therapy as soon as patients are clinically stable reduces the length of hospitalization and associated costs. Fluoroquinolones are appropriate candidates for switch therapy. Gatifloxacin is an excellent choice when a fluoroquinolone is being considered for sequential switch therapy in the treatment of CAP requiring hospitalization.

Randomized controlled trial of sequential intravenous (i.v.) and oral moxifloxacin compared with sequential i.v. and oral co-amoxiclav with or without clarithromycin in patients with community-acquired pneumonia requiring initial parenteral treatment

The objective of the present trial was to compare the efficacy, safety, and tolerability of moxifloxacin (400 mg) given intravenously (i.v.) once daily followed by oral moxifloxacin (400 mg) for 7 to 14 days with the efficacy, safety, and tolerability of co-amoxiclav (1.2 g) administered by i.v. infusion three times a day followed by oral co-amoxiclav (625 mg) three times a day, with or without clarithromycin (500 mg) twice daily (i.v. or orally), for 7 to 14 days in adult patients with community-acquired pneumonia requiring initial parenteral therapy. A total of 628 patients were enrolled and assessed by evaluation of their clinical and bacteriological responses 5 to 7 days and 21 to 28 days after administration of the last dose of study medication. Although the trial was designed, on the basis of predefined outcomes, to demonstrate the equivalence of the two regimens, the results showed statistically significant higher clinical success rates (for moxifloxacin, 93.4%, and for comparator regimen, 85.4%; difference [Delta], 8.05%; 95% confidence interval [CI], 2.91 to 13.19%; P = 0.004) and bacteriological success rates (for moxifloxacin, 93.7%, and for comparator regimen, 81.7%; Delta, 12.06%; 95% CI, 1.21 to 22.91%) for patients treated with moxifloxacin. This superiority was seen irrespective of the severity of the pneumonia and whether or not the combination therapy included a macrolide. The time to resolution of fever was also statistically significantly faster for patients who received moxifloxacin (median time, 2 versus 3 days), and the duration of hospital admission was approximately 1 day less for patients who received moxifloxacin. The treatment was converted to oral therapy immediately after the initial mandatory 3-day period of i.v. administration for a larger proportion of patients in the moxifloxacin group than patients in the comparator group (151 [50.2%] versus 57 [17.8%] patients). There were fewer deaths (9 [3.0%] versus 17 [5.3%]) and fewer serious adverse events (38 [12.6%] versus 53 [16.5%]) in the moxifloxacin group than in the comparator group. The rates of drug-related adverse events were comparable in both groups (38.9% in each treatment group). The overall incidence of laboratory abnormalities was similar in both groups. Thus, it is concluded that monotherapy with moxifloxacin is superior to that with a standard combination regimen of a beta-lactam and a beta-lactamase inhibitor, co-amoxiclav, with or without a macrolide, clarithromycin, in the treatment of patients with community-acquired pneumonia admitted to a hospital.

Severe community-acquired pneumonia: current outcomes, epidemiology, etiology, and therapy

Severe community-acquired pneumonia is a clinical diagnosis with a significant impact on healthcare management around the world, with the highest morbidity and mortality of all of the forms of community-acquired pneumonia. Patients with severe pneumonia usually require intensive care unit management, including vasopressors or mechanical ventilation. Early clinical suspicion and prompt empiric antimicrobial therapies are mandatory in patients with severe pneumonia. A number of recent studies and guidelines addressing these issues have been published, and they will be reviewed in this article.