Caspofungin versus amphotericin B for candidemia: A pharmacoeconomic analysis

Pharmacoeconomic evaluation of micafungin versus caspofungin as definitive therapy for candidaemia and invasive candidiasis (IC) in Turkey

Micafungin was shown to be as efficacious as caspofungin in treating patients with candidaemia and invasive candidiasis (IC). However, it remains unknown if micafungin or caspofungin is a cost-effective definitive therapy for candidaemia and IC in Turkey. The present study aimed to determine the economic impact of using micafungin versus caspofungin for treatment of candidaemia and IC in the Turkish setting. A decision analytic model was constructed and was populated with data (i.e. transition probabilities, duration of initial antifungal treatment, reasons for treatment failure, percentage of patients who stepped down to oral fluconazole, and duration on oral fluconazole) obtained from a published randomised clinical trial. Cost inputs were derived from the latest Turkish resources while data that were not readily available in the literature were estimated by expert panels. One-way sensitivity analyses, threshold analyses, scenario analyses and probabilistic sensitivity analyses were conducted. Caspofungin (€2693) incurred a lower total cost than micafungin (€4422), with a net cost saving of €1729 per treated patient. Drug acquisition cost was the main cost driver for both study arms. The model outcome was robust over wide variations (of ±100.0% from the base case value) for all input parameters except for micafungin drug cost and the duration of initial treatment with micafungin. Caspofungin appears to be a cost-saving option in treating candidaemia and IC from the Turkish hospital perspective.

Treatment of invasive candidiasis: between guidelines and daily clinical practice

Invasive candidiasis, including candidemia (IC/C), is a major cause of morbidity and mortality among hospitalized patients. While incidence is higher in intensive care units, the majority of cases of candidemia are documented in medical wards. Although Candida albicans is still the most frequently isolated species, IC/C due to non-albicans species, usually less susceptible to fluconazole, is increasing. Early identification of patients at risk, knowledge of local epidemiology and prompt efforts to define etiologic diagnosis play a pivotal role for appropriateness. Starting therapy with an echinocandin, switching then to fluconazole when possible, seems to represent a potentially useful strategy for the management of IC/C. The choice between the three echinocandins should be based on the specific indications, pharmacokinetic/pharmacodynamic profile, clinical experience and relative cost.

Impact of first-line antifungal agents on the outcomes and costs of candidemia

Candida species are the leading causes of invasive fungal infection among hospitalized patients and are responsible for major economic burdens. The goals of this study were to estimate the costs directly associated with the treatment of candidemia and factors associated with increased costs, as well as the impact of first-line antifungal agents on the outcomes and costs. A retrospective study was conducted in a sample of 199 patients from four university-affiliated tertiary care hospitals in Korea over 1 year. Only costs attributable to the treatment of candidemia were estimated by reviewing resource utilization during treatment. Risk factors for increased costs, treatment outcome, and hospital length of stay (LOS) were analyzed. Approximately 65% of the patients were treated with fluconazole, and 28% were treated with conventional amphotericin B. The overall treatment success rate was 52.8%, and the 30-day mortality rate was 47.9%. Hematologic malignancy, need for mechanical ventilation, and treatment failure of first-line antifungal agents were independent risk factors for mortality. The mean total cost for the treatment of candidemia was $4,743 per patient. Intensive care unit stay at candidemia onset and antifungal switch to second-line agents were independent risk factors for increased costs. The LOS was also significantly longer in patients who switched antifungal agents to second-line drugs. Antifungal switch to second-line agents for any reasons was the only modifiable risk factor of increased costs and LOS. Choosing an appropriate first-line antifungal agent is crucial for better outcomes and reduced hospital costs of candidemia.

[Cost analysis of 3 candins in the treatment of invasive candidiasis in adult non-neutropaenic patients in Spain]

OBJECTIVE

To estimate the cost of 3 candins (anidulafungin, caspofungin and micafungin) in the treatment of adult non-neutropaenic patients with invasive candidiasis (IC) in a Spanish hospital pharmacy setting.

METHODS

The overall cost impact was evaluated by varying the percentage dosage required of each candin in different possible scenarios. The prices (in euros) for each presentation were obtained from the Drug Catalogue (in August 2010). Only drug purchase costs were considered. The results are expressed as total cost for each of the 3 candins.

RESULTS

The cost per episode (14 days) of anidulafungin was constant at €5400 per patient. The cost of caspofungin varied from €4281 to €7991, depending on patient weight and liver dysfunction. The cost of micafungin varied from €6000 (100mg/day) to €9000 (when increasing the dose due to inadequate response). Based on a hypothetic cohort of 100 patients with IC, the total cost of anidulafungin treatment would be €540,000, for caspofungin it would be €631,459, and for micafungin it would be €632,998, depending on any dose adjustment required.

CONCLUSION

Patients treated with anidulafungin did not require dose adjustment, unlike those treated with caspofungin or micafungin. The use of anidulafungin is a cost-saving treatment for adult non-neutropaenic patients with IC, which would result in better control of the Spanish pharmacy budget.

Resource utilization and cost of treatment with anidulafungin or fluconazole for candidaemia and other forms of invasive candidiasis: focus on critically ill patients

BACKGROUND

Candidaemia and other forms of invasive candidiasis (C/IC) are serious and costly events for hospitalized patients, particularly those in the ICU. Both fluconazole and the echinocandins are recommended as first-line therapy for C/IC. Resource use and cost considerations are important in selecting appropriate treatment but little information is available on the economic implications of using echinocandins in this setting.

OBJECTIVE

To compare resource utilization and treatment costs (in $US) associated with the echinocandin anidulafungin (200 mg intravenously on day 1, then 100 mg intravenously daily) versus those of fluconazole (800 mg intravenously on day 1, then 400 mg intravenously daily) as first-line treatment for C/IC.

METHODS

Available charts from patients enrolled in a recent clinical trial comparing anidulafungin and fluconazole for C/IC were reviewed. Patients who were in the ICU at study entry were identified, and the following data, collected during the 13-week study period, were compared between treatment groups: global response at end of study treatment, number of days patients survived after hospital discharge ('hospital-free' days), hospital resource use, and C/IC-related costs (year 2008 values) to a US hospital payer. These comparisons were also conducted for all non-ICU hospitalized patients, and for survivors in both study populations. Sensitivity analyses explored the cost impact of variability in the hospitalization costs between ICUs and non-ICU wards and of reduced duration intravenous therapy. Statistical comparisons between the two treatment groups were conducted for clinical outcomes, resource use and cost measures, using regression models. All statistical comparisons were adjusted for baseline co-variates (Acute Physiology and Chronic Health Evaluation [APACHE] II score, absolute neutrophil count and catheter removal status).

RESULTS

For ICU patients with C/IC (n = 63), global response was significantly higher for anidulafungin than fluconazole (68.6% vs 42.9%; p = 0.03). ICU patients treated with anidulafungin had an average of 13.9 more hospital-free days (18.2 vs 4.3 days; p = 0.04) than those treated with fluconazole. After adjustment for co-variates, although lower costs were observed for anidulafungin vs fluconazole in ICU patients and in ICU patients who survived, no statistical differences were found. For all hospitalized patients (n = 159), global response was also higher for anidulafungin (78.3% vs 60.5%; p < 0.01). There was no difference in average length of hospitalization (29.6 days) or hospital-free days. After adjustment for co-variates, anidulafungin treatment resulted in an incremental C/IC-related cost of $US2680 (p = 0.73). For hospitalized patients who survived (anidulafungin 81.9%, fluconazole 69.7%), anidulafungin treatment was associated with an incremental cost of $US231 (p = 0.98).

CONCLUSION

Anidulafungin as first-line treatment of C/IC appears to be of particular benefit to ICU patients, improving clinical outcomes and possibly decreasing costs, driven by reduced ICU and hospital stay, when compared with fluconazole. Anidulafungin also yielded significantly improved treatment outcomes in the general inpatient population, with total costs similar to fluconazole.

Treatment and prophylaxis of invasive candidiasis with anidulafungin, caspofungin and micafungin and its impact on use and costs: review of the literature

Invasive fungal infections are on the rise. Echinocandins are a relatively new class of antifungal drugs that act by inhibition of a key enzyme necessary for integrity of the fungal cell wall. Currently there are three available agents: caspofungin, micafungin and anidulafungin. While the individual echinocandin antifungals have a different spectrum of licensed indications, basically all of them are available for the treatment of candidemia and invasive candidiasis. Antifungal treatment modalities basically include in therapy for suspected or proven infection and prophylaxis. All three drugs are comparatively expensive. Therefore a systematic review of the literature was performed to investigate the following aspects: * General aspects of cost-effectiveness in the treatment of invasive fungal infections * Cost-effectiveness of the treatment with the above-mentioned antifungals * Cost-effectiveness in two settings: therapy and prophylaxis - Early initiation of antifungal therapy, adjustment after availability of microbiological results, duration of therapy, success and occurrence of severe complications (e.g. renal failure) are the most important cost drivers in antifungal therapy. - Considering the specific antifungals, for caspofungin the best evidence for cost-effectiveness is found in treatment of invasive candidiasis and in empiric therapy of suspected infections. Favourable economic data are available for micafungin as a cost-effective alternative to LAmB for prophylaxis in patients with hematopoietic stem cell transplantation (HSCT). For anidulafungin, cost-effectiveness was demostrated in a pharmacoeconomic model. Net savings - yet not significant - were observed in a retrospective chart review of 234 patients. Generally, however, most analyses are still based on pharmacoeconomic modelling rather than direct analysis of trial data or real-life clinical populations. - As an overall conclusion, using caspofungin, micafungin, or anidulafungin is not more expensive than using other established therapies. Micafungin has proven to be cost-effective in prophylaxis if the local fungal epidemiology indicates a high level of resistance to fluconazole. Switch strategies involving early initiation of broadly active therapy with switch to cheaper alternatives according to microbiology results and clinical status and early initiation of an appropriate therapy have been proven to be cost-efficient independent of the antifungal agent.

Overview of the changing epidemiology of candidemia

Candida spp. are currently the fourth most common cause of bloodstream infections in US hospitals, and the third most common cause of bloodstream infections in the intensive care unit. Over the last 2 decades there has been a shift towards a greater involvement of non-Candida albicans spp. as the cause of candidemia. Several of these non-albicans spp. (e.g., C. glabrata and C. krusei ) exhibit resistance to traditional triazole antifungals like fluconazole, and cross-resistance with newer triazoles, focusing attention on the first-line use of antifungals such as the echinocandins, which possess improved activity against fluconazole-resistant strains. Recent treatment guidelines from the Infectious Diseases Society of America (IDSA) recommend an echinocandin as primary therapy for nonneutropenic or neutropenic patients with moderately severe to severe candidiasis and for patients at risk for infection with a triazole-resistant strain. However, further improvement in candidemia-associated mortality will only be attainable with the development and validation of new diagnostic tools that will allow earlier detection, discrimination, and treatment of invasive candidiasis. Clinicians should remain vigilant to wider emergence of Candida spp. with echinocandin resistance.

Comparative cost-effectiveness of posaconazole versus fluconazole or itraconazole prophylaxis in patients with prolonged neutropenia

PURPOSE

A cost-effectiveness analysis was performed to investigate the financial impact of using posaconazole versus fluconazole or itraconazole prophylaxis in patients with prolonged neutropenia.

METHODS

A decision-analytic model was developed from a hospital perspective based on the use of posaconazole versus fluconazole or itraconazole prophylaxis in patients with prolonged neutropenia (i.e., longer than 7-10 days). Data reported in a multicenter study, medication-cost information, and reports of costs to treat invasive fungal infections were used to accurately populate the model. Sensitivity analyses enhanced the robustness of the model through variation of all probabilities and costs.

RESULTS

In the base case, patients initiated on posaconazole displayed a 45% reduction in overall cost as compared with patients initiated on fluconazole or itraconazole ($3051 versus $5529, respectively). Sensitivity analyses determined that univariate changes in all model variables, including medication cost, duration of therapy, and cost of treating invasive fungal infections, did not impact overall results. A Monte Carlo simulation analysis found that use of posaconazole remains the best overall prophylactic strategy when taking into consideration the potential variance in all model assumptions. Posaconazole dominated the use of fluconazole or itraconazole because of previously demonstrated lower incidence of breakthrough fungal infections and lower overall treatment cost.

CONCLUSION

The decision model indicated that use of posaconazole as prophylaxis in patients with prolonged neutropenia should result in lower overall treatment costs relative to the cost of fluconazole or itraconazole.

Treatment of invasive candidal infections: systematic review and meta-analysis

OBJECTIVE

To compare available antifungal treatments for invasive candidiasis, a leading cause of nosocomial bloodstream infections.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials that compared different antifungal agents for the treatment of candidemia and other forms of invasive candidiasis. Two reviewers independently appraised the quality of trials and extracted data. The primary outcome was all-cause mortality, and secondary outcomes were microbiological failure, treatment failure, and adverse events. Relative risks (RRs) with 95% confidence intervals (CIs) were pooled.

RESULTS

Of the 15 included trials, 9 compared fluconazole with other drugs (amphotericin B, itraconazole, or a combination of fluconazole and amphotericin B), 4 compared echinocandins with other drugs (fluconazole, amphotericin B, liposomal amphotericin B), 1 compared micafungin and caspofungin, and 1 compared amphotericin B plus fluconazole and voriconazole. No difference in mortality was observed with fluconazole vs amphotericin B (RR, 0.92; 95% CI, 0.72-1.17); however, the rate of microbiological failure increased in the fluconazole arm (RR, 1.52; 95% CI, 1.12-2.07). Anidulafungin decreased the rate of microbiological failure compared with fluconazole (RR, 0.50; 95% CI, 0.29-0.86) with fewer adverse events. Caspofungin was comparable to amphotericin B in mortality and efficacy, with fewer adverse events requiring discontinuation (RR, 0.11; 95% CI, 0.04-0.36). Micafungin was comparable to liposomal amphotericin B in mortality.

CONCLUSION

All assessed antifungal agents showed similar efficacy, but the rate of microbiological failure increased with fluconazole vs amphotericin B or anidulafungin. Amphotericin B is associated with a higher rate of adverse events than fluconazole and echinocandins.

Candidemia in the in-patient setting: treatment options and economics

Candidemia is the most common nosocomial fungal infection in the US. More than one in four adults who acquire candidemia in the hospital setting die prior to discharge. In addition to high case-fatality rates and other adverse clinical outcomes in survivors, candidemia is associated with a substantial economic burden. High costs associated with complex diagnostics and procedures contribute to this burden, as do new pharmacotherapeutic approaches. Despite the high costs of many antifungal agents recommended for the treatment of candidemia, unambiguous clinical evidence to guide treatment selection does not exist. This article reviews the clinical and economic burdens of candidemia, describes candidemia cost drivers and discusses existing pharmacoeconomic data regarding the cost-effectiveness of candidemia rapid identification and treatment approaches.

Treatment options in candidaemia

Candida spp. are the fourth leading cause of bloodstream infections. Mortality in candidaemia remains substantial. In recent years Candida non-albicans species are increasing. Inadequate and delayed antifungal treatment for candidaemia is associated with increased hospital mortality. While fluconazole has been shown to be safe and effective in Candida albicans, amphotericin B deoxycholate has substantial adverse events although being effective in most patients with candidaemia caused by non-albicans species. With the advent of new antifungals the efficacy and safety of antifungal treatment have been improved substantially. This review summarises the new treatment options in candidaemia.

Pharmacoeconomic analysis of caspofungin versus liposomal amphotericin B as empirical antifungal therapy for neutropenic fever

PURPOSE

An analysis was conducted that evaluated and compared the cost differences between caspofungin and liposomal amphotericin B when the medications were used as empirical antifungal therapy for persistent fever during neutropenia.

METHODS

Rates of drug use and impaired renal function (IRF) were based on data from published studies. IRF was defined as a doubling of the serum creatinine level or, if the creatinine level was elevated at enrollment, an increase of at least 1 mg/dL. The estimates of the costs for drug acquisition and treating IRF were derived using published data and applied to compare caspofungin with liposomal amphotericin B. Sensitivity analyses were performed by varying the IRF and relative acquisition costs to assess the effect of these factors on the cost differences.

RESULTS

The acquisition costs per patient were 6942 dollars for liposomal amphotericin B and 3996 dollars for caspofungin. The estimated cost per patient from IRF was 3173 dollars for liposomal amphotericin B and 793 dollars for caspofungin. Combining drug acquisition and IRF costs, the overall treatment cost per patient for caspofungin was 5326 dollars less than for liposomal amphotericin B. In sensitivity analyses of drug costs, the price of liposomal amphotericin B would have to be 23.95 dollars per vial for the overall treatment costs to be equal.

CONCLUSION

Comparison of cost estimates derived from published data revealed that a combined estimate of acquisition costs and costs related to the treatment of IRF was lower for caspofungin than for liposomal amphotericin B for empirically treating patients with neutropenic fever.

Economic evaluation of the prevention and management of systemic fungal infections in neutropenic patients

Systemic fungal infections in neutropenic patients remain a clinical problem that is associated with morbidity and mortality. Continuing efforts are being made to develop improved (i.e., more effective or safe) drugs, and several new treatments have recently become available. These have increased the therapeutic options available to clinicians to address the problem of systemic fungal infections. Therapeutic choices are difficult when taking into account aspects of efficacy, safety and costs that are associated with the available alternatives. This review summarises the present status of health economic knowledge of the standard therapies that have been available for many years, and also reports on the most recent health economic evidence available for the newly developed treatment alternatives.