Preparation Times and Estimated Costs for Vancomycin Formulations: Does the Difference Matter?

Objective Infections from methicillin-resistant Staphylococcus aureus are increasingly treated in longterm care facilities, but long-term care pharmacies face high costs in the provision of sterile vancomycin for intravenous administration. This study compares pharmaceutical costs of outsourced, compounded, and room temperature premixed vancomycin formulations in a long-term care pharmacy. Design This retrospective observational study reviewed 124 orders of vancomycin. Means for total pharmacy preparation time, pharmacist labor time, and extrapolated time over complete course of treatment were compared for three vancomycin preparations: outsourced, compounded by pharmacy, and room temperature premixed vancomycin formulations. Cost calculations were generated using ingredient costs as reported by the pharmacy and median pharmacist labor costs as published from national sources. Results Mean total preparation times and pharmacist preparation times were shortest for premixed vancomycin. Over full courses of treatment, mean pharmacy preparation time for compounded was 5 hours 3 minutes (mean of 28 treatments) and 2 hours 8 minutes for premixed (mean of 54 treatments). Data on pharmacist time in outsourced orders were not available. Total pharmacy costs were $993.94 for compounded vancomycin, $2220.34 for outsourced, and $809.36 for room temperature premixed vancomycin. Conclusion There were reduced preparation times for room temperature premixed vancomycin compared with compounded and outsourced formulations for skilled nursing facilities. As multiple drug-resistant organism infections are increasingly treated in long-term care, finding cost-effective approaches to medication provision from pharmacies is critical.

A real-world cost-effectiveness study of vancomycin versus linezolid for the treatment of late-onset neonatal sepsis in the NICU in China

BACKGROUND AND OBJECTIVE

Currently, the detection rates of methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) in the blood cultures of neonates with sepsis exceed the national average drug resistance level, and vancomycin and linezolid are the primary antibacterial drugs used for these resistant bacteria according to the results of etiological examinations. However, a comprehensive evaluation of their costs and benefits in late-onset neonatal sepsis in a neonatal intensive care unit (NICU) has not been conducted. This study aimed to compare the cost and effectiveness of vancomycin and linezolid in treating neonatal sepsis in the NICU.

METHODS

A cost-effectiveness analysis of real-world data was carried out by retrospective study in our hospital, and the cost and effectiveness of vancomycin and linezolid were compared by establishing a decision tree model. The drug doses in the model were 0.6 g for linezolid and 0.5 g for vancomycin. The cost break down included cost of medical ward, NICU stay, intravenous infusion of vancomycin or linezolid, all monitoring tests, culture tests and drugs. The unit costs were sourced from hospital information systems. The effectiveness rates were obtained by cumulative probability analysis. One-way sensitivity analysis was used to analyze uncertain influencing factors.

RESULTS

The effectiveness rates of vancomycin and linezolid in treating neonatal sepsis in the NICU were 89.74% and 90.14%, respectively, with no significant difference. The average cost in the vancomycin group was ¥12261.43, and the average cost in the linezolid group was ¥17227.96. The incremental cost effectiveness was ¥12416.33 cost per additional neonate with treatment success in the linezolid group compared to vancomycin group at discharge. Factors that had the greatest influence on the sensitivity of the incremental cost-effectiveness ratio were the price of linezolid and the effectiveness rates.

CONCLUSIONS

The cost for treatment success of one neonate in linezolid group was ¥5449.17 more than that in vancomycin group, indicating that vancomycin was more cost-effective. Therefore, these results can provide a reference for a cost effectiveness treatment scheme for neonatal sepsis in the NICU.

Efficacy and Cost-effectiveness of Topical Vancomycin Powder in Primary Cementless Total Hip Arthroplasty

Topical vancomycin has been shown to effectively reduce infections after spinal surgery while remaining safe and cost-effective; however, there are few studies evaluating topical vancomycin in total hip arthroplasty. The authors hypothesized that the incidence of periprosthetic joint infection would decrease with the use of topical vancomycin in total hip arthroplasty and that topical vancomycin would be cost-effective. A retrospective patient chart review was performed to evaluate consecutive primary cementless total hip arthroplasties performed in the authors' hospital system between April 2015 and December 2016. Demographic data were collected. Periprosthetic joint infection was defined by Musculoskeletal Infection Society criteria. Statistical analysis included t test, Fisher's exact test, and logistic regression. The costs of vancomycin and postoperative infection were used to determine the absolute risk reduction (1/number needed to treat) threshold needed for topical vancomycin to be cost-effective. In this study, 309 patients (55.7%) undergoing total hip arthroplasty were treated with topical vancomycin, and 246 patients (44.3%) did not receive treatment. There were 2 infections in the vancomycin group (0.6% incidence), and 4 in the no vancomycin group (1.6% incidence). There was no statistical difference in infection rate between the 2 cohorts (P=.414). The absolute risk reduction was 0.98%, and the number needed to treat with topical vancomycin was 102 patients to prevent 1 periprosthetic joint infection. Topical vancomycin ($12 per vial) resulted in an expected cost savings of $904 per patient. Topical vancomycin is inexpensive and cost-effective. Although not statistically significant, the topical vancomycin group had a 60% lower incidence of infection. Further research regarding appropriate prophylactic topical and intravenous antibiotic use is needed prior to widespread adoption. [Orthopedics. 2019; 42(5):e430-e436.].

Potential for Cost Saving with Iclaprim Owing to Avoidance of Vancomycin-Associated Acute Kidney Injury in Hospitalized Patients with Acute Bacterial Skin and Skin Structure Infections

BACKGROUND AND OBJECTIVE

Vancomycin is the most prescribed antibiotic for hospitalized adults with skin and skin structure infections. Vancomycin is associated with acute kidney injury. Iclaprim is an antibiotic under development for the treatment of patients with acute bacterial skin and skin structure infections and is not associated with acute kidney injury. This economic model sought to determine the potential cost saving with iclaprim owing to avoidance of vancomycin-associated acute kidney injury among hospitalized patients with acute bacterial skin and skin structure infections.

MATERIALS AND METHODS

A hospital cost-minimization model was developed to estimate the overall cost impact of replacing empiric vancomycin with iclaprim among hospitalized adult patients with skin and skin structure infections. The structural model included: vancomycin acquisition; vancomycin assay; incidence of vancomycin-associated acute kidney injury; excess hospital length of stay if acute kidney injury occurred; frequency/cost of specialty physician consults after occurrence of acute kidney injury; and probability/cost of acute dialysis as a result of acute kidney injury. Iclaprim treatment duration was 7 days and iclaprim acquisition cost was varied to determine the upper end of the daily iclaprim price that still conferred cost savings relative to vancomycin. Duration of hospitalization for iclaprim was assumed to be the same as patients with no acute kidney injury.

RESULTS

Based on the overall acute kidney injury rate (9.2%), the neutral acquisition price threshold for iclaprim vs. vancomycin was US$1373.47/regimen. Across various subpopulations where acute kidney injury risk ranged between 9.2 and 16.7%, the daily iclaprim acquisition cost that still conferred cost savings was up to US$300/day.

CONCLUSIONS

Iclaprim has the potential to reduce the economic burden of acute bacterial skin and skin structure infections in hospitalized patients at risk for vancomycin-associated acute kidney injury when iclaprim acquisition is US$300/day or less.

Appropriateness of vancomycin therapeutic drug monitoring and its outcomes among non-dialysis patients in a tertiary hospital in Singapore

Background Vancomycin therapeutic drug monitoring (TDM) is commonly performed to ensure safe and effective use of the antibiotic. Aim of Study To evaluate appropriateness of vancomycin TDM and its outcomes in Singapore General Hospital. Method A retrospective, cross-sectional study was conducted between 1 January 2014 and 28 February 2014 involving patients who received ≥ 1 dose of intravenous vancomycin with TDM. Patient demographics and relevant vancomycin TDM data were collected from medical records. Results Of 746 vancomycin troughs measured among 234 patients, 459 troughs (61.5%) were taken inappropriately, with a median time of 2.6 h (interquartile range 1.1-4.3) before the next scheduled dose. Inappropriate interpretation of vancomycin troughs resulted in 41 unnecessary dose suspensions, 24 dose changes, and 102 unchanged vancomycin doses. The cost incurred due to inappropriate interpretation and measurement after discontinuation of treatment was US$7286. No differences in rates of vancomycin related nephrotoxicity, ototoxicity, recurrent infection, development of infection secondary to vancomycin resistant microorganism and mortality were observed (p > 0.05). Conclusion This study highlighted a high incidence of inappropriate vancomycin TDM which has led to increased healthcare cost.

A Systematic Literature Review of Economic Evaluations of Antibiotic Treatments for Clostridium difficile Infection

BACKGROUND AND OBJECTIVE

Clostridium difficile infection (CDI) is associated with high management costs, particularly in recurrent cases. Fidaxomicin treatment results in lower recurrence rates than vancomycin and metronidazole, but has higher acquisition costs in Europe and the USA. This systematic literature review summarises economic evaluations (EEs) of fidaxomicin, vancomycin and metronidazole for treatment of CDI.

METHODS

Electronic databases (MEDLINE®, Embase, Cochrane Library) and conference proceedings (ISPOR, ECCMID, ICAAC and IDWeek) were searched for publications reporting EEs of fidaxomicin, vancomycin and/or metronidazole in the treatment of CDI. Reference bibliographies of identified manuscripts were also reviewed. Cost-effectiveness was evaluated according to the overall population of patients with CDI, as well as in subgroups with severe CDI or recurrent CDI, or those at higher risk of recurrence or mortality.

RESULTS

Overall, 27 relevant EEs, conducted from the perspective of 12 different countries, were identified. Fidaxomicin was cost-effective versus vancomycin and/or metronidazole in 14 of 24 EEs (58.3%), vancomycin was cost-effective versus fidaxomicin and/or metronidazole in five of 27 EEs (18.5%) and metronidazole was cost-effective versus fidaxomicin and/or vancomycin in two of 13 EEs (15.4%). Fidaxomicin was cost-effective versus vancomycin in most of the EEs evaluating specific patient subgroups. Key cost-effectiveness drivers were cure rate, recurrence rate, time horizon, drug costs and length and cost of hospitalisation.

CONCLUSIONS

In most EEs, fidaxomicin was demonstrated to be cost-effective versus metronidazole and vancomycin in patients with CDI. These results have relevance to clinical practice, given the high budgetary impact of managing CDI and increasing restrictions on healthcare budgets.

OTHER

This analysis was initiated and funded by Astellas Pharma Inc.

Cost-effectiveness analysis on the use of fidaxomicin and vancomycin to treat Clostridium difficile infection in France

BACKGROUND

Fidaxomicin is a macrocyclic antibiotic with proven efficacy against Clostridium difficile infection (CDI) in adults. It was licensed in France in 2012, but, due to higher acquisition costs compared with existing treatments, healthcare providers require information on its cost/benefit profile.

OBJECTIVE

To compare healthcare costs and health outcomes of fidaxomicin and vancomycin, as reference treatment for CDI.

METHODS

A Markov model was used to simulate the treatment pathway, over 1 year, of adult patients with CDI receiving fidaxomicin or vancomycin. Several patient sub-groups (severe CDI; recurrent CDI; concomitant antibiotics; cancer; renal failure; elderly) were evaluated. Cost-effectiveness was analyzed based on cure and recurrence rates derived from published randomized clinical trials comparing fidaxomicin and vancomycin, and costs calculated from the payer perspective using French hospitalization data and drug cost databases. Model outputs included costs in euros (reference year 2014) and health outcomes (recurrence; sustained cure rates). Alternative scenario and sensitivity analyses were performed using data from other clinical trials in CDI, including one conducted in real-life clinical practice in France.

RESULTS

Drug acquisition costs were €1,692 higher in fidaxomicin-treated patients, but this was offset by the lower hospitalization costs with fidaxomicin, which were reduced by €1,722. The reduction in the cost of hospitalization was driven by the significantly lower number of recurrences in fidaxomicin-treated patients, offsetting the acquisition cost of fidaxomicin in all sub-groups except recurrent CDI and concomitant antibiotics.

CONCLUSION

This study demonstrated that, despite higher acquisition costs, the lower recurrence rate with fidaxomicin resulted in cost savings or low incremental costs compared with vancomycin.

Cost-Effectiveness Analysis of Five Competing Strategies for the Management of Multiple Recurrent Community-Onset Clostridium difficile Infection in France

Background

Clostridium difficile infection (CDI) is characterized by high rates of recurrence, resulting in substantial health care costs. The aim of this study was to analyze the cost-effectiveness of treatments for the management of second recurrence of community-onset CDI in France.

Methods

We developed a decision-analytic simulation model to compare 5 treatments for the management of second recurrence of community-onset CDI: pulsed-tapered vancomycin, fidaxomicin, fecal microbiota transplantation (FMT) via colonoscopy, FMT via duodenal infusion, and FMT via enema. The model outcome was the incremental cost-effectiveness ratio (ICER), expressed as cost per quality-adjusted life year (QALY) among the 5 treatments. ICERs were interpreted using a willingness-to-pay threshold of €32,000/QALY. Uncertainty was evaluated through deterministic and probabilistic sensitivity analyses.

Results

Three strategies were on the efficiency frontier: pulsed-tapered vancomycin, FMT via enema, and FMT via colonoscopy, in order of increasing effectiveness. FMT via duodenal infusion and fidaxomicin were dominated (i.e. less effective and costlier) by FMT via colonoscopy and FMT via enema. FMT via enema compared with pulsed-tapered vancomycin had an ICER of €18,092/QALY. The ICER for FMT via colonoscopy versus FMT via enema was €73,653/QALY. Probabilistic sensitivity analysis with 10,000 Monte Carlo simulations showed that FMT via enema was the most cost-effective strategy in 58% of simulations and FMT via colonoscopy was favored in 19% at a willingness-to-pay threshold of €32,000/QALY.

Conclusions

FMT via enema is the most cost-effective initial strategy for the management of second recurrence of community-onset CDI at a willingness-to-pay threshold of €32,000/QALY.

Continuous vs. intermittent vancomycin therapy for Gram-positive infections not caused by methicillin-resistant Staphylococcus aureus

BACKGROUND

The aim of this study was to evaluate the effects of vancomycin pharmacokinetics (PKs) on effectiveness and safety in the treatment of Gram-positive infections due to pathogens other than methicillin-resistant Staphylococcus aureus (MRSA).

METHODS

Prospective study including septic patients received either continuous (N.=21) or intermittent (N.=21) infusions of vancomycin; the target drug concentration was 15-20 mg/L and target area under the curve of vancomycin concentrations over the minimum inhibitory concentration of the pathogen on day 1 (AUC24/MIC) >400. Clinical and microbiological responses, the development of acute kidney injury (AKI) and therapy costs were recorded.

RESULTS

The median AUC24/MIC was 195(133-343) vs. 189(136-328) mg/L*h in the continuous and intermittent infusion groups. Target drug concentrations were achieved in 15/21 vs. 9/21 (P=0.12) patients and AUC24/MIC>400 in only 5/21 vs. 3/21 (P=0.35) patients of continuous and intermittent groups, respectively. High clinical cure (17/21 for continuous vs. 17/21 for intermittent, P=1.00) and microbiological eradication (17/21 vs. 15/21, P=0.47) were observed in both groups and not associated with drug concentrations or with AUC24/MIC. AKI was diagnosed during therapy in 5/21 patients in the continuous group and 8/21 in the intermittent group (P=0.32). The median total therapy costs were lower in the continuous than in the intermittent group (377 [304-485] vs. 552 [371-644] €, P=0.04).

CONCLUSIONS

Vancomycin resulted in high clinical response during non-MRSA Gram-positive infections treatment even at drug concentrations lower than those for MRSA. A continuous infusion of vancomycin was associated with a significant reduction in therapy costs compared to intermittent infusions.

Economic evaluation among Chinese patients with nosocomial pneumonia caused by methicillin-resistant Staphylococcus aureus and treated with linezolid or vancomycin: a secondary, post-hoc analysis based on a Phase 4 clinical trial study

OBJECTIVE

To assess cost-effectiveness of linezolid vs vancomycin in treating nosocomial pneumonia caused by methicillin-resistant Staphylococcus aureus (MRSA-NP) in China and the impact of renal failure on healthcare resource utilization (HCRU) and costs.

METHODS

Cost-effectiveness analysis was conducted based on data from the ZEPHyR trial, with efficacy measured by treatment success and costs calculated from HCRU. Confidence intervals (CI) for cost, efficacy and incremental cost-effectiveness ratios (ICER) were calculated by non-parametric bootstrap. Chi-square test was used for renal failure rate and t-test for HCRU/cost comparisons. Impact of renal failure was assessed using regression model.

RESULTS

Data from 448 patients (1:1 linezolid:vancomycin) were analyzed. More patients treated with linezolid achieved success (55% [95% CI = 48-62%]) than with vancomycin (45% [38-52%]). Treatment cost were ¥79,551 (95% CI = ¥72,421-¥86,680) for linezolid vs ¥77,587 (¥70,656-¥84,519) for vancomycin in Beijing, ¥90,995 (¥82,598-¥99,393) vs ¥89,448 (¥81,295-¥97,601) in Guangzhou, ¥82,383 (¥74,956-¥89,810) vs ¥80,799 (¥73,545-¥88,054) in Nanjing and ¥59,413 (¥54,366-¥64,460) vs ¥57,804 (¥52,613-¥62,996) in Xi'an. Per successful treatment, the ICER of linezolid over vancomycin were ¥19,719 (-¥143,553 to ¥320,980) (Beijing), ¥15,532 (-¥185,411 to ¥349,693) (Guangzhou), ¥15,904 (-¥161,935 to ¥314,987) (Nanjing) and ¥16,145 (-¥100,738 to ¥234,412) (Xi'an). From simulations, the majority of linezolid cases had greater efficacy and higher costs and more than one third had greater efficacy and lower costs. More vancomycin patients developed renal failure (15% vs 4%, p < 0.001). Patients with renal failure had higher cost (Nanjng: ¥100,449 (SD = ¥65,080) vs ¥74,944 (SD = ¥49,632), p = 0.002).

CONCLUSION

Linezolid was more cost-effective than vancomycin in treating MRSA-NP from a Chinese payer's perspective, and associated with less renal failure, HCRU and cost.

Linezolid Versus Vancomycin in the Empiric Treatment of Nosocomial Pneumonia: A Cost-Utility Analysis Incorporating Results from the ZEPHyR Trial

OBJECTIVE

To examine the cost-effectiveness of vancomycin versus linezolid in the empiric treatment of nosocomial pneumonias incorporating results from a recent prospective, double-blind, multicenter, controlled trial in adults with suspected methicillin-resistant Staphylococcus aureus (MRSA) nosocomial pneumonia.

METHODS

A decision-analytic model examining the cost-effectiveness of linezolid versus vancomycin for the empiric treatment of nosocomial pneumonia was created. Publicly available cost, efficacy, and utility data populated relevant model variables. A probabilistic sensitivity analysis varied parameters in 10,000 Monte-Carlo simulations, and univariate sensitivity analyses assessed the impact of model uncertainties and the robustness of our conclusions.

RESULTS

Results indicated that the cost per quality-adjusted life-year (QALY) increased 6% ($22,594 vs. $23,860) by using linezolid versus vancomycin for nosocomial pneumonia. The incremental cost per QALY gained by using linezolid over vancomycin was $6,089, and the incremental cost per life saved was $68,615 with the use of linezolid. Vancomycin dominated linezolid in the subset of patients with documented MRSA. The incremental cost per QALY gained using linezolid if no mortality benefit exists between agents or a 60-day time horizon was analyzed was $19,608,688 and $443,662, respectively.

CONCLUSIONS

Linezolid may be a cost-effective alternative to vancomycin in the empiric treatment of patients with suspected MRSA nosocomial pneumonia; however, results of our model were highly variable on a number of important variables and assumptions including mortality differences and time frame analyzed.

Cost savings analysis of intrawound vancomycin powder in posterior spinal surgery

BACKGROUND CONTEXT

Recent studies have shown that prophylactic use of intrawound vancomycin in posterior instrumented spine surgery substantially decreases the incidence of wound infections requiring repeat surgery. Significant cost savings are thought to be associated with the use of vancomycin in this setting.

PURPOSE

To elucidate cost savings associated with the use of intrawound vancomycin in posterior spinal surgeries using a budget-impact model.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

Data from a cohort of 303 patients who underwent spinal surgery (instrumented and noninstrumented) over 2 years were analyzed; 96 of these patients received prophylactic intrawound vancomycin powder in addition to normal intravenous (IV) antibiotic prophylaxis, and 207 received just routine IV antibiotic prophylaxis. Patients requiring repeat surgical procedures for infection were identified, and the costs of these additional procedures were elucidated.

OUTCOME MEASURE

Cost associated with the additional procedure to remediate infection in the absence of vancomycin prophylaxis.

METHODS

We retrospectively reviewed the cost of return procedures for treatment of surgical site infection (SSI). The total reimbursement received by the health care facility was used to model the costs associated with repeat surgery, and this cost was compared with the cost of a single local application of vancomycin costing about $12.

RESULTS

Of the 96 patients in the treatment group, the return-to-surgery rate for SSI was 0. In the group without vancomycin, seven patients required a total of 14 procedures. The mean cost per episode of surgery, based on the reimbursement, the health care facility received was $40,992 (range, $14,459-$114,763). A total of $573,897 was spent on 3% of the 207-patient cohort that did not receive intrawound vancomycin, whereas a total of $1,152 ($12×96 patients) was spent on the cohort treated with vancomycin.

CONCLUSIONS

This study shows a reduction in SSIs requiring a return-to-surgery-with large cost savings-with use of intrawound vancomycin powder. In our study population, the cost savings totaled more than half a million dollars.

Modeling economic implications of alternative treatment strategies for acute bacterial skin and skin structure infections

OBJECTIVE

The economic implications from the US Medicare perspective of adopting alternative treatment strategies for acute bacterial skin and skin structure infections (ABSSSIs) are substantial. The objective of this study is to describe a modeling framework that explores the impact of decisions related to both the location of care and switching to different antibiotics at discharge.

METHODS

A discrete event simulation (DES) was developed to model the treatment pathway of each patient through various locations (emergency department [ED], inpatient, and outpatient) and the treatments prescribed (empiric antibiotic, switching to a different antibiotic at discharge, or a second antibiotic). Costs are reported in 2012 USD.

RESULTS

The mean number of days on antibiotic in a cohort assigned to a full course of vancomycin was 11.2 days, with 64% of the treatment course being administered in the outpatient setting. Mean total costs per patient were $8671, with inpatient care accounting for 58% of the costs accrued. The majority of outpatient costs were associated with parenteral administration rather than drug acquisition or monitoring. Scenarios modifying the treatment pathway to increase the proportion of patients receiving the first dose in the ED, and then managing them in the outpatient setting or prescribing an oral antibiotic at discharge to avoid the cost associated with administering parenteral therapy, therefore have a major impact and lower the typical cost per patient by 11-20%. Since vancomycin is commonly used as empiric therapy in clinical practice, based on these analyses, a shift in treatment practice could result in substantial savings from the Medicare perspective.

CONCLUSIONS

The choice of antibiotic and location of care influence the costs and resource use associated with the management of ABSSSIs. The DES framework presented here can provide insight into the potential economic implications of decisions that modify the treatment pathway.

Cost-Effectiveness Analysis of the Treatment of Ventilator-Associated Pneumonia with Linezolid or Vancomycin in Spain

The aim of this study was to assess the cost-effectiveness of linezolid (LIN) versus vancomycin (VAN) for the treatment of ventilator-associated pneumonia (VAP) using a decision model analysis from the National Health System perspective. Patients and participants comprising four subgroups were analyzed: all, Gram-positive (GP), Staphylococcus aureus (SA), methicillin-resistant SA (MRSA). The treatments were LIN 600 mg i.v., every 12 hours, 10 days and VAN 1,000 mg i.v., every 12 hours 10 days. The primary outcome was the incremental cost-effectiveness of LIN in terms of cost per added quality-adjusted life year (QALY) gained. The secondary outcome was the marginal cost per year of life saved (LYS) generated by using LIN. Clinical cure and survival rates estimates were derived from a retrospective analysis of two trials comparing LIN with VAN. QALY was based on time-trade off study. Resource use and unit costs (Euros 2003) were obtained from Spanish VAP treatment and health cost databases. The additional QALY and LYS per LIN patients were 0.392; 0.688; 0.606; 1.805 and 0.471; 0.829; 0.729; 2.175 respectively, compared with those of VAN in the patients with VAP (all, GP, SA, and MRSA, respectively). The additional costs for LYS with LIN, as compared to VAN were 1,501.31; 827.63; 955.13 and 289.51 Euros, respectively. The additional cost per QALY with LIN was 1,803.87; 997.25; 1,149.00 and 348.85 Euros, respectively.

CONCLUSIONS

LIN was more cost-effective than VAN in the treatment of VAP in Spain, with an additional cost per QALY/LYS gained below the acceptable threshold in Spain of Euros 30,000 for new therapies.

Ceftaroline fosamil use in hospitalized patients with acute bacterial skin and skin structure infections: Budget impact analysis from a hospital perspective

PURPOSE

The budgetary impact of adding ceftaroline fosamil to a hospital formulary for the treatment of acute bacterial skin and skin structure infections (ABSSSIs) was evaluated.

METHODS

A three-year hospital budget impact model was constructed with three initial treatment options for ABSSSIs: ceftaroline fosamil, vancomycin plus aztreonam, and other vancomycin-containing regimens. The target population was hospitalized adult patients with an ABSSSI. Clinical cure rates with initial treatment were assumed to be similar to those from ceftaroline fosamil clinical trials. Patients who did not respond to initial treatment were assumed to be treated successfully with second-line antimicrobial therapy. Length of stay and cost per hospital day (by success or failure with initial treatment) were estimated based on a large database from more than 100 U.S. hospitals. Other model inputs included the annual number of ABSSSI admissions, projected annual case growth rate, proportion of ABSSSI target population receiving vancomycin-containing regimen, expected proportion of ABSSSI target population to be treated with ceftaroline fosamil, drug acquisition cost, cost of antibiotic administration, and cost of vancomycin monitoring. Sensitivity analysis using 95% confidence limits of clinical cure rates was also performed.

RESULTS

The estimated total cost of care for treating a patient with an ABSSSI was $395 lower with ceftaroline fosamil ($15,087 versus $15,482) compared with vancomycin plus aztreonam and $72 lower ($15,087 versus $15,159) compared with other vancomycin-containing regimens.

CONCLUSION

Model estimates indicated that adding ceftaroline fosamil to the hospital formulary would not have a negative effect on a hospital's budget for ABSSSI treatment.

Cost-effectiveness analysis evaluating fidaxomicin versus oral vancomycin for the treatment of Clostridium difficile infection in the United States

OBJECTIVES

Fidaxomicin is a novel treatment for Clostridium difficile infections (CDIs). This new treatment, however, is associated with a higher acquisition cost compared with alternatives. The objective of this study was to evaluate the cost-effectiveness of fidaxomicin or oral vancomycin for the treatment of CDIs.

METHODS

We performed a cost-utility analysis comparing fidaxomicin with oral vancomycin for the treatment of CDIs in the United States by creating a decision analytic model from the third-party payer perspective.

RESULTS

The incremental cost-effectiveness ratio with fidaxomicin compared with oral vancomycin was $67,576/quality-adjusted life-year. A probabilistic Monte Carlo sensitivity analysis showed that fidaxomicin had an 80.2% chance of being cost-effective at a willingness-to-pay threshold of $100,000/quality-adjusted life-year. Fidaxomicin remained cost-effective under all fluctuations of both fidaxomicin and oral vancomycin costs. The decision analytic model was sensitive to variations in clinical cure and recurrence rates. Secondary analyses revealed that fidaxomicin was cost-effective in patients receiving concominant antimicrobials, in patients with mild to moderate CDIs, and when compared with oral metronidazole in patients with mild to moderate disease. Fidaxomicin was dominated by oral vancomycin if CDI was caused by the NAP1/Bl/027 Clostridium difficile strain and was dominant in institutions that did not compound oral vancomycin.

CONCLUSION

Results of our model showed that fidaxomicin may be a more cost-effective option for the treatment of CDIs when compared with oral vancomycin under most scenarios tested.

[Pharmacoeconomic analysis of the treatment of methicillin-resistant Staphylococcus aureus with daptomycin or vancomycin]

INTRODUCTION

The increased morbidity, mortality and high costs associated with bacteremia caused by methicillin-resistant Staphylococcus aureus (MRSA) is a major public health problem. Pharmacoeconomic analysis was performed to compare the efficiency of daptomycin (DAP) against vancomycin (VAN) in the treatment of this infection.

METHODS

Retrospective, deterministic and probabilistic cost-effectiveness analysis. The effectiveness of the treatments was estimated from the results of a randomized clinical trial, which compared DAP (6 mg / kg IV daily) and VAN (1 g IV every 12 hours), both with or without gentamicin (1 mg / kg IV every 8 hours). Resource utilization was estimated from the clinical trial of the drug datasheets and Spanish sources, the unit costs were obtained also from Spanish sources. Monte Carlo probabilistic analysis and deterministic analysis were performed.

RESULTS

The clinical trial cure rates were higher with DAP (44.4%, 95% CI 43.5 to 45.4%) than with VAN (31.8%, 95% CI 30.9 to 32.7%) not statistically significant (p = 0.2203) but with economic impact. With DAP would occur less costs due to treatment failure (rescue antibiotics, additional tests, prolonged hospital stay and adverse reactions) than with VAN. In the base case the average cost of disease per patient was € 12,329 to € 12,696 with DAP and VAN (difference of 367 €). DAP treatment was dominant (more effective, with lower costs than VAN) both in the deterministic and probabilistic analysis. In the Monte Carlo simulation, DAP was the most cost-effective treatment in 100% of the 10,000 simulations, for a willingness to pay € 12,000 per additional cure (approximate cost of MRSA bacteraemia episode).

CONCLUSIONS

According to this model, daptomycin is more cost-effective than vancomycin in treating MRSA bacteremia. The higher cost of acquisition of daptomycin does not imply a higher cost of treating this infection.

Outcomes and costs associated with a history of vancomycin exposure in patients with MRSA-related complicated bacteremia and infective endocarditis

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) is the primary cause of complicated bacteremia (CB) and infective endocarditis (IE). Studies have compared the costs of treatment with vancomycin to those of other agents, as well as the efficacy and tolerability of these treatments. However, a literature search found no published studies of the effects of vancomycin exposure on outcomes and hospital costs in patients with CB or IE due to MRSA.

OBJECTIVE

The aim of this study was to determine whether there is a quantitative relationship between the duration of vancomycin treatment or cumulative vancomycin exposure and outcomes or costs in patient with CB or IE due to MRSA.

METHODS

Electronic medical records of confirmed cases of MRSA-related CB or IE from July 1, 2006, to June 30, 2008, were retrospectively reviewed to identify patients with a history of vancomycin exposure or no vancomycin exposure. Those who received vancomycin were stratified by the amount of drug administered or the duration of treatment to determine the relationship between treatment and outcomes. Data collected included demographic information, treatment information, attributable mortality, MIC data, and hospital costs. Classification and regression tree analysis (CART) was used to determine whether a history of vancomycin exposure was associated with treatment failure, attributable mortality, or both. The Mann-Whitney U test and the Fisher exact test were used for univariate analyses, and logistic regression was used for multivariate modeling.

RESULTS

Data from 50 patients were evaluated (CB, 32; IE, 18). Overall rates of failure and attributable mortality were 32% and 16%, respectively. No significant differences were observed between the variables and costs. The CART break points for failure were ≥18.75 g and ≥14 days of vancomycin treatment in the previous 3 years; for attributable mortality, the CART break points were ≥45 g and ≥31 days. In the final multivariate model for failure, ≥18.75 g and ≥14 days of vancomycin treatment in the previous 3 years were predictors of failure (both, P = 0.002). Acute Physiology and Chronic Health Evaluation (APACHE) II score (P = 0.04), ≥45 g (P = 0.002), and ≥31 days of treatment (P = 0.002) in the previous 3 years were predictors of attributable mortality after adjustment for all covariates.

CONCLUSIONS

Using the present model, cumulative vancomycin amount and duration were associated with attributable mortality and clinical failure but not with costs.

[Pharmacoeconomic assessment of daptomycin as first-line therapy for bacteraemia and complicated skin and skin structure infections caused by gram-positive pathogens in Spain]

OBJECTIVE

To assess the efficiency of daptomycin as firstline therapy (D) versus daptomycin as salvage therapy after vancomycin (V→D ) or linezolid (L→D) failure in gram-positive bacteraemia and complicated skin and skin-structure infections (cSSTIs).

METHODS

Cost-effectiveness analysis of 161 bacteraemia and 84 cSSTIs patients comparing the above mentioned therapeutic alternatives was performed using the data from 27 Spanish hospitals involved in the EUCORE study. Direct medical costs were considered. Patients were observed from the first antibiotic dose for infection until either the end of daptomycin therapy or exitus. A multivariate Monte Carlo probabilistic sensitivity analysis was applied for costs (lognormal distribution) and effectiveness (normal distribution).

RESULTS

In terms of effectiveness there were no statistical differences between groups but referring total costs per patient, there were significant differences. Sensitivity analysis confirmed that D dominates over L→D between 44.2%-62.1% of simulations in bacteraemia and between 48.2%-67.5% in cSSTIs. In comparison to V→D, D dominance was detected in 29.2%-33.2% of simulations in bacteraemia and between 48.2%-59.3% in cSSTIs.

CONCLUSIONS

Daptomycin as first-line therapy dominates over daptomycin as salvage therapy after linezolid failure both in bacteraemia and cSSTIs. Comparing daptomycin as first-line therapy with its use after vancomycin failure, in cSSTIs the former is dominant. In bacteremia daptomycin as first line therapy is as effective as daptomycin as salvage therapy after vancomycin failure and implies lower costs.

Cost-effectiveness analysis of linezolid, daptomycin, and vancomycin in methicillin-resistant Staphylococcus aureus: complicated skin and skin structure infection using Bayesian methods for evidence synthesis

BACKGROUND

Methicillin-resistant Staphylococcus aureus (MRSA) complicated skin and skin structure infection (cSSSI) is a prominent infection encountered in hospital and outpatient settings that is associated with high resource use for the health-care system.

OBJECTIVE

A decision analytic (DA) model was developed to evaluate the cost-effectiveness analysis (CEA) of linezolid, daptomycin, and vancomycin in MRSA cSSSI.

METHODS

Bayesian methods for evidence synthesis were used to generate efficacy and safety parameters for a DA model using published clinical trials. CEA was done from the US health-care perspective. Efficacy was defined as a successfully treated patient at the test of cure without any adverse reaction. Primary outcome was the incremental cost-effectiveness ratio between linezolid and vancomycin, daptomycin and vancomycin, and linezolid and daptomycin in MRSA cSSSI. Univariate and probabilistic sensitivity analyses were performed to test the robustness of the model.

RESULTS

The total direct costs of linezolid, daptomycin, and vancomycin were $18,057, $20,698, and $23,671, respectively. The cost-effectiveness ratios for linezolid, daptomycin, and vancomycin were $37,604, $44,086, and $52,663 per successfully treated patient, respectively. Linezolid and daptomycin were dominant strategies compared to vancomycin. However, linezolid was dominant when compared to daptomycin. The model was sensitive to the duration of daptomycin and linezolid treatment.

CONCLUSION

Linezolid and daptomycin are potentially cost-effective based on the assumptions of the DA model; however, linezolid appears to be more cost-effective compared to daptomycin and vancomycin for MRSA cSSSIs.

Cradle-to-gate life cycle inventory of vancomycin hydrochloride

A life cycle analysis on the cradle-to-gate production of vancomycin hydrochloride, which begins at natural resource extraction and spans through factory (gate) production, not only shows all inputs, outputs, and energy usage to manufacture the product and all related supply chain chemicals, but can highlight where process changes would have the greatest impact on raw material and energy consumption and emissions. Vancomycin hydrochloride is produced by a low-yield fermentation process that accounts for 47% of the total cradle-to-gate energy. The fermentation step consumes the most raw materials and energy cradle-to-gate. Over 75% of the total cradle-to-gate energy consumption is due to steam use; sterilization within fermentation is the largest user of steam. Aeration and agitation in the fermentation vessels use 65% of the cradle-to-gate electrical energy. To reduce raw materials, energy consumption, and the associated environmental footprint of producing vancomycin hydrochloride, other sterilization methods, fermentation media, nutrient sources, or synthetic manufacture should be investigated. The reported vancomycin hydrochloride life cycle inventory is a part of a larger life cycle study of the environmental consequences of the introduction of biocide-coated medical textiles for the prevention of MRSA (methicillin-resistant Staphylococcus aureus) nosocomial infections.

An economic model for the prevention of MRSA infections after surgery: non-glycopeptide or glycopeptide antibiotic prophylaxis?

AIM

Surgical site infection is commonly caused by Staphylococcus aureus. The multiresistant strains (MRSA) are resistant to most antibiotic prophylaxis regimens. Our aim was to explore whether there is a threshold of MRSA prevalence at which switching to routine glycopeptide-based antibiotic prophylaxis becomes cost-effective.

METHODS

An indicative model was designed to explore the cost-effectiveness of vancomycin, cephalosporin or a combination, in patients undergoing primary hip arthroplasty.

RESULTS

If the MRSA infection rate is equal to or above 0.25% and the rate of other infections with cephalosporin prophylaxis is equal to or above 0.2%, use of the combination antibiotic prophylaxis is optimal.

DISCUSSION

Modelling the cost-effectiveness of interventions for MRSA prevention is complex due to uncertainty around resistance and effectiveness of glycopeptides.

CONCLUSIONS

The indicative model provides a framework for evaluation. More work is needed to understand the impact of antibiotic resistance over time in these currently effective antibiotics.

Cost-effectiveness analysis of linezolid vs. vancomycin in treating methicillin-resistant Staphylococcus aureus complicated skin and soft tissue infections using a decision analytic model

PURPOSE

To evaluate the cost-effectiveness of vancomycin vs. linezolid in complicated skin and soft tissue infections (cSSTIs) with methicillin-resistant Staphylococcus aureus (MRSA) using a decision analytic (DA) model.

METHODS

A DA model was created to evaluate the cost-effectiveness of four treatment strategies in the treatment of MRSA cSSTIs: linezolid intravenous (i.v.) to oral (LIN), vancomycin i.v. inpatient treatment (VAN-1), vancomycin i.v. switch to oral linezolid (VAN-2) and vancomycin i.v. switch to outpatient vancomycin i.v. (VAN-3). Probabilities were determined from published clinical trials. Incremental cost-effectiveness ratios for the various strategies were the primary outcome. Univariate (one-way) sensitivity analysis and second-order Monte Carlo simulation (using 10,000 trials) were conducted for all parameters used in the model.

RESULTS

The DA model predicted that VAN-3 was the most cost-effective strategy from the base-case analysis. Average cost-effectiveness ratio for this strategy was $26,831.42/cure. Univariate sensitivity analysis revealed that the model was sensitive to linezolid duration of inpatient stay and duration of i.v. vancomycin before switching to an oral agent or discharged with outpatient i.v. administration with vancomycin. Probabilistic sensitivity analysis showed that VAN-1 was dominated by LIN, but LIN was only 30% cost-effective compared with VAN-3. Acceptability curve showed that the probability of choosing LIN as a cost-effective strategy compared with VAN-1, VAN-2 and VAN-3 increased as the willingness-to-pay (WTP) increased.

CONCLUSION

Alternative vancomycin strategies (VAN-2 and VAN-3) that take advantage of early discharge opportunities were cost-effective compared with LIN. However, LIN's higher efficacy would make it cost-effective for payers with a high WTP threshold.

Cost-effectiveness of linezolid versus vancomycin for hospitalised patients with complicated skin and soft-tissue infections in Germany

This study used a decision analytic model approach to evaluate the cost-effectiveness of linezolid versus vancomycin in the empirical treatment of complicated skin and soft-tissue infection (cSSTI) due to suspected methicillin-resistant Staphylococcus aureus (MRSA) from the German hospital and health care system perspective. Clinical probabilities were obtained from trial data, resource utilisation and MRSA prevalence rates were obtained through German physician interviews, and costs from published sources were applied to resource units. Outcomes included total cost/patient and cure. The estimated first-line cure rate for linezolid-treated patients was 90.1% versus 85.5% for vancomycin; total cure rates after two lines of treatment were 98.4% and 98.1%, respectively. Average total cost/episode was 8,232 euro for linezolid versus 9,206 euro for vancomycin. The model outcomes were sensitive to changes in length of stay (LOS), isolation days, rate of confirmed MRSA and price of linezolid. Linezolid was expected to result in a shorter intravenous treatment duration and shorter LOS that offset its higher acquisition cost versus vancomycin in cSSTI in Germany.

Outcomes associated with initial versus later vancomycin use in patients with complicated skin and skin-structure infections

BACKGROUND

Delayed coverage of pathogens including meticillin-resistant Staphylococcus aureus (MRSA) in pneumonia and bacteraemia has been associated with increased mortality and length of hospital stay (LOS). However, less is known about the impact of delayed appropriate coverage in complicated skin and skin-structure infections (cSSSIs).

OBJECTIVE

To evaluate the clinical and economic outcomes associated with early versus late use of vancomycin in the management of patients hospitalized for cSSSIs.

METHODS

Retrospective analysis was performed using an inpatient claims database of >500 US hospitals in 2005. Using prescription claims, patients with primary or secondary cSSSI admissions were classified into three groups: 1 = early vancomycin monotherapy; 2 = early vancomycin combination therapy; 3 = late vancomycin therapy. Outcomes studied included LOS and inpatient hospital costs. One-way analysis of variance was used for unadjusted analysis and multivariate regression methods were used to control for co-variates.

RESULTS

A total of 34,942 patients (27.78% of all patients with cSSSIs) were treated with vancomycin. Mean age was 54.7 years and 54.3% of the patients were males. Mean unadjusted total LOS was 8.46, 9.44 and 13.2 days, and hospital costs in 2005 values were USD10 211.94, USD12 361.94 and USD18 344.00 for groups 1, 2 and 3, respectively. In-hospital mortality rate was highest in group 3 (4.18%) and lowest in group 1 (1.75%). Generalized linear models used to control for potential confounding variables between early versus late vancomycin use suggest that among cSSSI patients late vancomycin use is an independent predictor of higher LOS and costs.

CONCLUSION

In this large inpatient database, later vancomycin use in patients with cSSSIs appears to be significantly associated with higher LOS and total costs.

A comparison of costs and hospital length of stay associated with intravenous/oral linezolid or intravenous vancomycin treatment of complicated skin and soft-tissue infections caused by suspected or confirmed methicillin-resistant Staphylococcus aureus in elderly US patients

OBJECTIVES

This study compared the costs and hospital length of stay (LOS) and duration of intravenous therapy associated with intravenous/oral linezolid or intravenous vancomycin treatment of complicated skin and soft-tissue infections (cSSTIs) caused by suspected or confirmed methicillin-resistant Staphylococcus aureus (MRSA) in elderly US patients.

METHODS

Data were obtained from elderly (>or=65 years) US patients participating in a multinational randomized trial of hospitalized cSSTI patients treated with linezolid or vancomycin. Costs (hospital and total) from the provider perspective were estimated for intent-to-treat (ITT) patients (ie, all those receiving >or=1 dose) using national 2003 costs (ward, medication, intravenous administration). LOS for inpatient care, duration of intravenous linezolid and vancomycin therapy (ITT and MRSA groups), and cure rates were evaluated.

RESULTS

Of 717 enrolled subjects, 163 (23%) were elderly (87 linezolid, 76 vancomycin), with no significant differences in demographic characteristics between the linezolid and vancomycin groups. Mean hospitalization and total costs were lower with linezolid compared with vancomycin (hospitalization: US $4510 vs US $6478, P<0.001; total: US $6009 vs US $7329, P=0.03). Linezolid was associated with a 3.5-day reduction in LOS and a 9.5-day reduction in the duration of intravenous therapy compared with vancomycin in the ITT group (both, P<0.001). Cure rates were comparable between linezolid and vancomycin in both the ITT group (88.7% vs 81.4%, respectively) and the MRSA group (80.0% vs 71.4%). In multivariate analyses of the ITT group, linezolid patients were 57% less likely than vancomycin patients to have a LOS >7 days (odds ratio = 0.43; 95% CI, 0.21-0.87). Chronic renal failure, malnutrition, and a diagnosis of infected ulcer predicted an LOS >7 days.

CONCLUSIONS

In this analysis of data from elderly patients with cSSTI caused by suspected or confirmed MRSA, linezolid treatment was associated with reductions in the costs of care, LOS, and duration of intravenous treatment without affecting the clinical outcomes. Although the use of a subset of patients from a larger trial that did not focus on the elderly can be seen as a study limitation, the elderly represent an important population when evaluating health care resource use and costs.

Linezolid versus Vancomycin for Prosthetic Joint Infections: a Cost Analysis

BACKGROUND

Prosthetic joint infections (PJIs) caused by methicillin-resistant gram-positive bacteria are primarily treated by intravenous vancomycin. Linezolid, active against methicillin-resistant strains and available in oral and intravenous dosage forms, is a potential alternative to vancomycin for the treatment of PJIs.

OBJECTIVE

To analyze the cost of linezolid therapy (outpatient setting) and vancomycin therapy (inpatient and outpatient settings) for PJIs caused by methicillin-resistant gram-positive bacteria.

METHODS

A decision tree was designed to simulate the clinical outcome and healthcare resource utilization of linezolid, vancomycin by outpatient and home parenteral antimicrobial therapies (OHPAT) and vancomycin administered in inpatient setting (rehabilitation facility) for patients with PJIs caused by methicillin-resistant strains. Clinical inputs were estimated from literature and the cost analysis was conducted from the perspective of the public healthcare provider in Hong Kong.

RESULTS

The base-case analysis showed that the vancomycin (OHPAT) group (USD14,470 per patient) was the least costly alternative, followed by the linezolid group (USD17,877 per patient) and the vancomycin (rehabilitation) group (USD19,980 per patient) (1USD = 7.8HKD). The clinical treatment success rates of vancomycin and linezolid were influential factors. Monte Carlo 10,000 simulations showed that the vancomycin (OHPAT) group was less costly than the arms of linezolid and vancomycin (rehabilitation) 64% and 100% of the time, respectively. The linezolid group was less costly than the vancomycin (rehabilitation) group in 65%of the times.

CONCLUSION

Home-infusion of vancomycin therapy appears to be the least costly treatment approach for PJIs caused by methicillin-resistant gram-positive bacteria from the perspective of a Hong Kong public health organization.

Cost-effectiveness of linezolid and vancomycin in the treatment of surgical site infections

OBJECTIVE

This decision-analytic study was intended to determine the expected cost-effectiveness of linezolid compared to vancomycin for treating surgical site infections (SSIs) caused by methicillin-resistant Staphyloccocus aureus (MRSA) from the perspective of a tertiary-care academic medical center.

RESEARCH DESIGN AND METHODS

This study is a cost-effectiveness analysis based on a modeling approach for the treatment of MRSA SSIs. Three clinical scenarios were considered in the decision analysis: (1) treatment with intravenous (IV) vancomycin during hospitalization and after discharge with home-care follow-up; (2) treatment with IV vancomycin during hospitalization, followed by oral linezolid after discharge; (3) treatment with oral linezolid during hospitalization and after discharge. Cost data was obtained from internal and external sources. Cure rate probabilities for MRSA SSIs were obtained from records at the medical center and from results of a randomized, multicenter trial. Healthcare costs for each scenario were obtained from the medical center, healthcare buying groups, and national databases. The robustness of the baseline cost-effectiveness determination was evaluated using sensitivity analyses over a broad range of costs and probabilities.

RESULTS

Treatment with oral linezolid during hospitalization and after discharge (scenario 3) was associated with lower costs (8923, 11,479, and 12,481 dollars, respectively) and greater effectiveness (0.867, 0.787, and 0.707, respectively) compared to the IV vancomycin/oral linezolid switch (scenario 2) and IV vancomycin (scenario 1), so it dominated the latter options in the base-case, incremental cost-effectiveness analysis (10,292, 14,486, and 17,653 dollars per MRSA SSI cure, respectively). Furthermore, the sensitivity analysis demonstrated that the IV vancomycin/oral linezolid (scenario 2) option would be the expected cost-effective choice only if the length of hospitalization for this scenario was less than 6 days or if the probability of cure with oral linezolid (scenario 3) was less than or equal to 0.72; otherwise, the oral linezolid option was dominant. A major limitation of this study is the utilization of probability estimates from both institutional and published research sources. Additionally, the success rates for linezolid were obtained from one relatively small randomized, open-label trial.

CONCLUSIONS

Using decision-analytic modeling, treatment with oral linezolid during hospitalization and after discharge is expected to be the most cost-effective approach for treating SSIs caused by MRSA.

The economic effect of oral linezolid versus intravenous vancomycin in the outpatient setting: the payer perspective

Oral antibiotic therapy can reduce complications and costs compared with intravenous (IV) therapy. The object of this study was to determine the health economic and resource utilization effects of outpatient treatment with oral linezolid relative to IV vancomycin. Longitudinal claims data from 80 health care plans were used. Patients 18 years and older, who did not have osteomyelitis, with a pharmacy claim for linezolid or vancomycin between January 1, 2002 and March 31, 2004 were eligible. Clinical and resource utilization data were collected for 12 months before and 35 days after treatment. Patients treated with linezolid were matched with controls treated with vancomycin, based on propensity scoring. Direct medical costs paid by health plans were compared. A total of 1,048 matched pairs were identified. Demographic and clinical characteristics were comparable between groups. Patients with linezolid claims had lower resource utilization versus those with vancomycin claims during follow-up, including fewer mean physician office visits (4.1+/-5.7 vs. 8.4+/-13.8 visits; P< .001); lab/diagnostic claims (6.3+/-18.0 vs. 10.4 +/-15.2 claims; P< .001); pharmacy claims (7.3+/-8.1 vs. 13.6+/-17.4 claims; P< .001); emergency room visits (9.7% vs. 13.9%; P= .003) and hospitalization (15.3% vs. 19.1%; P= .024). Patients receiving vancomycin were more likely to be hospitalized or have an emergency room visit than patients receiving linezolid. Mean total adjusted cost was 4,707 dollars less for linezolid compared with vancomycin (8,401dollars vs. 13,108 dollars; P< .001). Similar trends were observed for patients matched based on complicated skin and soft tissue infection diagnosis. Outpatient treatment with oral linezolid was associated with significantly lower resource utilization and total medical costs compared with IV vancomycin.

Outpatient parenteral antibiotic therapy in Singapore

Outpatient parenteral antibiotic therapy (OPAT) remains in its infancy in Singapore, with the first patients enrolled 4 years ago. Singapore's three largest hospitals, with over 3000 inpatient beds, now have designated and approved OPAT services. This study reviews the demographic, clinical and cost data of all patients enrolled in 2005 to facilitate benchmarking between services in Singapore and abroad and also to identify common needs for further development. In 2005, 225 OPAT enrollments in 208 different patients resulted in 4050 days of OPAT care. Orthopaedic diagnoses constituted 40% of admissions. Vancomycin was the most frequently used antibiotic (34%). The re-admission rate was 8.9%, but complications of OPAT care were only occasionally implicated. An estimated $207,200 was saved by patients despite there being significant financial disincentives to subsidised patients. OPAT is a safe, cost-efficient system that is becoming increasingly accepted in Singapore by patients, clinicians and management. Our three services have evolved independently into very similar practices. There is potential for further innovation, including outreach and carer-delivered dosing. However, major financial disincentives require review.

Impact of linezolid on economic outcomes and determinants of cost in a clinical trial evaluating patients with MRSA complicated skin and soft-tissue infections

BACKGROUND

In clinical trials, linezolid has demonstrated higher clinical cure rates and shorter hospital duration for patients than has vancomycin for the treatment of complicated skin and soft-tissue infections (cSSTIs).

OBJECTIVE

To assess economic outcomes of linezolid versus vancomycin and evaluate determinants of treatment costs for cSSTIs.

METHODS

Economic data were obtained from US subjects enrolled in a multinational, open-label, clinical trial of cSSTIs caused by suspected or proven methicillin-resistant Staphylococcus aureus (MRSA). Subjects were randomized to receive intravenous or oral linezolid or intravenous vancomycin for 7-21 days. Costs for each patient were evaluated by applying nationally representative per diem hospital costs by hospital ward. Intravenous administration costs were applied to the duration of intravenous treatment. Factors contributing to the cost of therapy were evaluated using multivariate regression analysis.

RESULTS

Seven hundred seventeen US patients were included in the study. Demographics were similar between treatment groups. Length of stay and duration of intravenous therapy were shorter for linezolid-treated patients. Mean +/- SD cost for intent-to-treat population patients treated with linezolid versus vancomycin was 4865 US dollars +/- 4367 versus 5738 US dollars +/- 5190, respectively (p = 0.017), and in the MRSA population was 4881 US dollars +/- 3987 versus 6006 US dollars +/- 5039, respectively (p = 0.041). Factors significantly associated with increased cost included vancomycin therapy, age, and comorbidities, including diabetes. After adjusting for all other factors, treatment with linezolid was associated with significantly lower treatment costs compared with vancomycin.

CONCLUSIONS

Linezolid therapy was associated with improved clinical outcomes and significantly lower treatment costs than was vancomycin. The largest cost advantage was demonstrated in patients with documented MRSA cSSTIs.

Impact of rapid in situ hybridization testing on coagulase-negative staphylococci positive blood cultures

OBJECTIVES

To evaluate the impact of the rapid differentiation of Staphylococcus aureus from coagulase-negative staphylococci (CoNS) in blood cultures using peptide nucleic acid fluorescence in situ hybridization (PNA FISH) on vancomycin usage, length of patient hospital stay and hospital costs.

DESIGN

This was a retrospective, cost-effective analysis of PNA FISH in its initial 3 month implementation period in 2004 in a 650 bed academic medical centre. Blood cultures with Gram-positive cocci in clusters (GPCC) that were negative for S. aureus using the PNA FISH assay were compared with an untested control group in the same period that had similar illness severity and location. We evaluated the effectiveness of the early identification of CoNS by ruling out S. aureus in conjunction with an antimicrobial team (AMT) on antimicrobial therapy, patient length of stay and hospital costs.

RESULTS

A total of 139 blood cultures positive with GPCC had PNA FISH results while 84 in the control group did not. Evaluable criteria were met in 53 patients in the PNA FISH group and 34 in the control group. When comparing the results obtained from using the PNA FISH assay with those for the control group, there was a significant reduction in median length of hospital stay from 6 to 4 days (P < 0.05, CI 0.95-1.87) and a trend towards less vancomycin usage with a decrease in associated hospital costs of approximately Dollars 4000 per patient.

CONCLUSIONS

The PNA FISH assay is rapid, accurate and reliable and in association with an AMT could decrease hospital length of stay in patients with CoNS bacteraemia in non-intensive care unit settings and prevent excessive vancomycin usage.

Health economics assessment study of teicoplanin versus vancomycin in Gram-positive infections

The objective of this study, conducted at Hospital Clínico San Carlos, Madrid, Spain, was to compare the cost of treatment of Gram-positive infections with teicoplanin and vancomycin under normal conditions. Using a prospective observational study design for drug utilization and economic assessment, we evaluated the comparability of the sample, adverse events, features of treatment with teicoplanin/vancomycin and factors influencing the consumption of resources until the end of glycopeptide treatment or discharge (whichever occurred later) using Health System perspective. Costs were assigned using the hospital's evaluation at the time of the study. Analyses made: multivariate, sensitivity (by modifying staff or acquisition costs) and simulation of reduction of stay by early discharge in the teicoplanin group. Study participants included 201 patients who had been using teicoplanin (n=100) or vancomycin (n=101) for at least four days. Data collected daily outside morning work timetable. Costs of acquisition, administration and monitoring by course of treatment (mean+/-SD, in euros) were lower in the vancomycin group (teicoplanin euro647.62+/-euro572.75 vs. vancomycin euro378.11+/-euro225.90); when total costs (including hospital stay) were considered, no differences were found (teicoplanin euro4,432.04+/-euro3,383.46 vs. vancomycin euro4,364.44+/-euro2,734.24). Conditions of use and results were similar for both antibiotics. The economic results of acquisition, administration and monitoring were advantageous for vancomycin; when global costs of care were taken into account, these differences were not evident. Tolerability was significantly advantageous in the teicoplanin group (with regard to phlebitis and elevation of creatininemia), without differences in clinical or economic outcomes. The formulation of teicoplanin did not take advantage of its potential benefits of administration.

Clinical and economic outcomes of pharmacist-managed aminoglycoside or vancomycin therapy

PURPOSE

The associations between pharmacist-managed aminoglycoside or vancomycin therapy for hospitalized Medicare patients who had diagnoses indicating probable treatment with these antibiotics and the major health care outcomes of death rate, length of stay, Medicare charges, hearing loss, and renal impairment were explored.

METHODS

Pharmacist management of drug therapy was evaluated in a study population composed of 199,082 Medicare patients treated in 961 hospitals.

RESULTS

In hospitals that did not have pharmacist-managed aminoglycoside or vancomycin therapy, death rates were 6.71% higher (1,048 excess deaths [chi(2) (1) = 43.801, p < 0.0001]), length of stay was 12.28% higher (131,660 excess patient days [U = 4.701 x 10(9), p < 0.0001]), total Medicare charges were 6.30% higher (140,745,924 US dollars in excess total Medicare charges [U = 4.864 x 10(9), p < 0.0001]), drug charges were 8.15% higher (34,769,250 US dollars in excess drug charges [U = 4.785 x 10(9), p < 0.0001]), laboratory charges were 7.80% higher (22,530,474 US dollars in excess laboratory charges [U = 4.860 x 10(9), p < 0.0001]), hearing loss was 46.42% higher (134 more patients with hearing loss [chi(2) = 54.423, df = 1, p < 0.0001]), renal impairment was 33.95% higher (2,801 more patients with renal impairment [chi(2) = 118.13, df = 1, p < 0.0001]), and the death rate in patients who developed complications was 10.15% higher (231 excess deaths [chi(2) = 22.345, df = 1, p < 0.0001]) than in hospitals with pharmacists managing these drugs.

CONCLUSION

The presence of pharmacist-managed aminoglycoside or vancomycin therapy was associated with significant improvement in health care and economic outcomes for Medicare patients who received these drugs.

Cost-effectiveness of linezolid versus vancomycin in mechanical ventilation-associated nosocomial pneumonia caused by methicillin-resistant staphylococcus aureus

Linezolid, an oxazolidinone-class antimicrobial agent, is a new drug; its use has frequently been questioned due to its high price. However, recent trials have demonstrated that the use of linezolid in mechanical ventilation-associated nosocomial pneumonia caused by methicillin-resistant Staphylococcus aureus (VAP-MRSA) may be justified due to its improved efficacy compared to vancomycin. Price and cost have different magnitudes, and clinical efficacy should always be considered in the decision-making process. Our objective was to determine whether linezolid treatment was more cost-effective than vancomycin for treating VAP-MRSA.

METHODOLOGY

Elaboration of an economic model from a metanalysis of previous clinical trials comparing both drugs, through a cost-effectiveness analysis. Costs of the treatments were calculated using Brazilian parameters and were compared to the results obtained in the metanalysis. In order to compare the results with real life conditions, costs were calculated for both name brand and for generic vancomycin.

RESULTS

The cost (May/2004) per unit (vial, ampoule or bag) was R$ 47.73 for the name-brand vancomycin, R$ 14.45 for generic vancomycin and R$ 214.04 for linezolid. Linezolid's efficacy in VAP-MRSA according to the metanalysis was 62.2% and vancomycin's efficacy was 21.2%. The total cost per cured patient was R$ 13,231.65 for the name-brand vancomycin, R$ 11,277.59 for generic vancomycin and R$ 7,764.72 for linezolid.

CONCLUSION

Despite the higher price per unit, linezolid was more cost-effective than vancomycin.

Clinical and economic outcomes of oral linezolid versus intravenous vancomycin in the treatment of MRSA-complicated, lower-extremity skin and soft-tissue infections caused by methicillin-resistant Staphylococcus aureus

BACKGROUND

Resistant bacteria often complicate the management of skin and soft tissue infections of the lower extremities. This open-label study compared oral linezolid and intravenous vancomycin for management of complicated skin and soft-tissue infections caused by methicillin-resistant Staphylococcus aureus (MRSA).

METHODS

Patients aged 18 years or older with proven MRSA-related complicated skin and soft-tissue infections requiring surgical intervention were randomized to receive oral linezolid (n=30) or intravenous vancomycin (n=30) for 7 to 21 days. Clinical and microbiological outcomes, duration of hospitalization and drug treatment, and outpatient charges were determined.

RESULTS

Linezolid was associated with greater rates of clinical cure and improvement (P=.015), a 3-day shorter median length of stay (P=.003), and reduced outpatient charges (P<.001). Vancomycin therapy was associated with more treatment failures and subsequent lower-extremity amputations (P=.011).

CONCLUSIONS

Clinical outcomes were significantly better with linezolid than with vancomycin. Additionally, linezolid was associated with reduced length of stay and outpatient charges.

Vancomycin dosing in high flux hemodialysis: a limited-sampling algorithm

PURPOSE

The feasibility of using a limited-sampling algorithm for administration of vancomycin for treatment of vascular-access-related bacteremia in outpatient high flux hemodialysis was investigated.

METHODS

The original vancomycin-dosing algorithm used at our hemodialysis unit required stat orders for serum vancomycin concentrations before each hemodialysis session to determine the dose of vancomycin to be administered posthemodialysis. Vancomycin concentration data obtained using this original algorithm from January through September 2001 were retrospectively analyzed to determine how many vancomycin concentrations measured 5-20 microg/mL and identify potential clinical predictors of vancomycin removal.

RESULTS

A total of 409 serum vancomycin concentrations were drawn during the study period. Ninety-seven percent of concentrations drawn were within 5-20 microg/mL. Twenty-eight patients had data evaluable to determine pharmacokinetic parameters. Mean +/- S.D. vancomycin removal was 39% +/- 13%. Body weight and duration of dialysis alone, blood flow rate, and dialysate flow rate were not predictive of vancomycin removal. Based on these data, a revised algorithm with limited vancomycin sampling data was initiated in December 2002. Retrospective analysis of concentrations obtained and achieved by this algorithm demonstrated a 70% reduction in the number of vancomycin concentration determinations, with 93% of these concentrations within 5-20 microg/mL. The estimated annual cost saving to the hemodialysis unit with the revised algorithm was 7552 dollars.

CONCLUSION

A vancomycin-dosing algorithm using limited concentration monitoring for hemodialysis patients achieved comparable vancomycin concentrations to those found with more frequent monitoring and resulted in significant cost savings.

Addition of Teicoplanin or Vancomycin for the Treatment of Documented Bacteremia due to Gram-Positive Cocci in Neutropenic Patients with Hematological Malignancies: Microbiological, Clinical and Economic Evaluation

A prospective, randomized, double-blind trial was conducted on 124 febrile patients with hematological malignancies to compare teicoplanin with vancomycin as an addition to the initial empiric amikacin-ceftazidime regimen after documented bacteremia due to gram-positive cocci. At enrollment, patients in both groups were comparable with respect to age, sex, underlying hematologic disorders and duration of neutropenia. Rates of therapeutic success were 55/63 (87.3%) in the teicoplanin group and 56/61 (91.8%) in the vancomycin group (p = 0.560). The mean duration of treatment was similar, being 12.2 and 11.4 days, respectively (p = 0.216). Patients treated with teicoplanin remained febrile for slightly longer than those treated with vancomycin (4.9 vs. 4.0 days) (p = 0.013). Thirteen patients experienced an adverse drug reaction, but without any significant difference in the two arms. Isolated staphylococci showed a progressive and significant decrease in susceptibility to both glycopeptides during the 8 study years. The economic analysis performed showed that the addition of vancomycin is cost-saving.

Direct medical costs associated with using vancomycin in methicillin-resistant Staphylococcus aureus infections: an economic model

OBJECTIVES

To quantify the direct medical costs associated with using vancomycin, as inpatient treatment, in methicillin-resistant Staphylococcus aureus infections, in four clinical indications: complicated skin and soft tissue infections (SSTI), bacteremia, infective endocarditis (IE), and hospital-acquired pneumonia (HAP).

RESEARCH DESIGN AND METHODS

A decision-analytic model was constructed to evaluate the cost of administering intravenous vancomycin. Cost inputs included hospitalization, drug procurement, materials, preparation and administration, renal function and drug monitoring, treating adverse events, and treatment failure. Probabilities and lengths of stay and treatment were obtained from the literature, an antimicrobial therapy database and clinical expert opinion. Univariate and multivariate sensitivity analyses were conducted to confirm the robustness of the baseline scenario.

MAIN OUTCOME MEASURES

The cost of using vancomycin in the four indications, including and excluding hospital cost.

RESULTS

Whereas the drug acquisition price of vancomycin 1g is US dollars 9.01 per dose, when all costs associated with using vancomycin were included, the cost per dose rose to US dollars 29-US dollars 43 per patient. Total costs per patient receiving multiple doses in a single course of treatment, excluding hospital room costs, were for SSTI, bacteremia, IE, and HAP,US dollars 779, US dollars 749, US dollars 2261, and US dollars 768, respectively. Total costs, including hospital length of stay, were for SSTI US dollars 23616, bacteremia US dollars 26446, IE US dollars 48925, and HAP US dollars 22493. In univariate analyses varying per diem hospital costs and length of stay had the greatest impact. Results of the multivariate analysis were comparable to the costs in the baseline scenario for all indications.

CONCLUSIONS

This analysis highlights the importance of capturing all costs associated with using a drug and not simply focusing on drug acquisition cost. Future economic analyses should identify and account for the key cost burdens of a particular treatment to calculate its true cost.

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.

Cost analysis of switching from IV vancomycin to PO linezolid for the management of methicillin-resistant Staphylococcus species

BACKGROUND

Infections with methicillin-resistant Staphylococcus species (MRSS) are associated with higher treatment costs than infections with methicillin-sensitive Staphylococcus species in the United States--partly because of an increased length of hospital stay (LOS).

OBJECTIVE

This study used pharmacoeconomic modeling to evaluate the costs and outcomes associated with the use of i.v. vancomycin compared with p.o. linezolid in the treatment of MRSS-infected patients.

METHODS

A retrospective chart review was used to determine the number of cases with confirmed or presumed MRSS infections treated with i.v. vancomycin during calendar-year 2000 at the Veterans Affairs Greater Los Angeles Healthcare System inpatient facility. Patients who were eligible for a switch to p.o. linezolid with or without early discharge to home were identified. Cost differences associated with conversion from i.v. to p.o. therapy (compared with continued i.v. therapy) were estimated based on a mean decreased LOS and a decrease in the costs associated with catheter-related adverse events. Rates and costs of catheter-related adverse events were based on estimates from the literature. Sensitivity analyses were performed by variation of the estimated mean LOS decrease in the SD and by variation of the estimates for incidence and costs related to catheter complications. Costs were measured in year 2000 US dollars, and differences were not assessed for statistical significance.

RESULTS

Of 177 patients treated with i.v. vancomycin, 103 (58%) were eligible for conversion to p.o. linezolid and 55 (31%) were eligible for early discharge from the hospital with continuation of p.o. therapy. Early discharge was associated with a mean (SD) LOS decrease of 3.3 (2.9) days. Annual mean total cost savings in patients eligible for conversion from i.v. vancomycin to p.o. linezolid with early discharge were $294,750 (range, $35,730-$553,790). For cases eligible for inpatient conversion from i.v. vancomycin to p.o. linezolid therapy (n=48), the mean total annual cost difference was an increase of $6340 for p.o. linezolid (range, -$12,910 to $11,900).

CONCLUSION

These results--although partly based on estimates from the literature, rather than direct measurements--support the use of p.o. linezolid with or without early discharge as a potential cost-savings alternative for eligible patients treated with a full course of i.v. vancomycin for suspected or confirmed MRSS infection.