Utilization and dosage pattern of echinocandins for treatment of fungal infections in US hospital practice

Fungal diseases: could nanostructured drug delivery systems be a novel paradigm for therapy?

Invasive mycoses are a major problem for immunocompromised individuals and patients in intensive care units. Morbidity and mortality rates of these infections are high because of late diagnosis and delayed treatment. Moreover, the number of available antifungal agents is low, and there are problems with toxicity and resistance. Alternatives for treating invasive fungal infections are necessary. Nanostructured systems could be excellent carriers for antifungal drugs, reducing toxicity and targeting their action. The use of nanostructured systems for antifungal therapy began in the 1990s, with the appearance of lipid formulations of amphotericin B. This review encompasses different antifungal drug delivery systems, such as liposomes, carriers based on solid lipids and nanostructure lipids, polymeric nanoparticles, dendrimers, and others. All these delivery systems have advantages and disadvantages. Main advantages are the improvement in the antifungal properties, such as bioavailability, reduction in toxicity, and target tissue, which facilitates innovative therapeutic techniques. Conversely, a major disadvantage is the high cost of production. In the near future, the use of nanosystems for drug delivery strategies can be used for delivering peptides, including mucoadhesive systems for the treatment of oral and vaginal candidiasis.

[Echinocandins: Applied pharmacology]

The echinocandins share pharmacodynamic properties, although there are some interesting differences in their pharmacokinetic behaviour in the clinical practice. They are not absorbed by the oral route. They have a somewhat special distribution in the organism, as some of them can reach high intracellular concentrations while, with some others, the concentration is reduced. They are highly bound to plasma proteins, thus it is recommended to administer a loading dose for anidulafungin and caspofungin, although this procedure is not yet clear with micafungin. Echinocandins are excreted via a non-microsomal metabolism, so the urinary concentration is very low. Some carrier proteins that take part in the biliary clearance process are probably involved in the interactions described with caspofungin and micafungin. These two drugs must be used with caution in patients with severely impaired hepatic function, while all of them can be used without special precautions when there is renal impairment or the patient requires renal replacement therapy.

The impact of clinical pharmacist and ID intervention in rationalization of antimicrobial use

What is known and objective

There is little research on the impact of implementing and monitoring antimicrobial policy in Saudi hospitals. The purpose of this study is to measure the impact of the clinical pharmacist (CP) and infectious disease consultant (ID) interventions on the use of three antimicrobials (caspofungin, imipenem, meropenem) in hospitalized patients in the King Abdullah Medical City hospital.

Methods

The study was carried out in the King Abdullah Medical City, in Mekkah, Saudi Arabia. The hospital is a tertiary center that provides CCU, CSICU, Cardiac, Hematology, ICU, Medical, Neuroscience, Oncology, and specialized surgery services. The use of three antimicrobials (caspofungin, imipenem, meropenem) was reviewed by the clinical pharmacist for four periods, pre and post implementation of policy. Relevant data were collected in four periods. In the first period, before policy implementation, data were collected retrospectively to be used as baseline status reference, and in the three remaining periods that followed data were collected prospectively, and compared to baseline data, to evaluate the role of clinical pharmacist and ID interventions in optimizing antimicrobial therapy.

Results and discussion

Caspofungin duration of therapy was not affected significantly by the intervention. Statistically significant reduction in antimicrobial therapy duration was observed in imipenem (37%) and meropenem (37%) from baseline, which indicate a better control on antimicrobial use and reduction in antimicrobial resistance.

What is new and conclusion

The impact of the clinical pharmacist and ID interventions, in reducing antimicrobial therapy duration using imipenem and meropenem, is clear from the result presented above. However, lack of restriction and follow up in the antimicrobial policy in case of negative culture makes antimicrobial use uncontrollable in these cases. Establishing good and accepted policy may help reduce consumption and total cost of therapy.

Utilization of critical care services among patients undergoing total hip and knee arthroplasty: epidemiology and risk factors

BACKGROUND

A paucity of data exist on the use of critical care services (CCS) among hip and knee arthroplasty patients. The authors sought to identify the incidence and risk factors for the use of CCS among these patients and compare the characteristics and outcomes of patients who require CCS to those who do not.

METHODS

The authors analyzed hospital discharge data of patients who underwent primary hip or knee arthroplasty in approximately 400 United States hospitals between 2006 and 2010. Patient and healthcare system-related demographics for admitted patients requiring CCS were compared with those who did not. Differences in outcomes, including mortality, complications, disposition status, and hospital charges, were analyzed. Regression analysis was performed to identify risk factors for requiring CCS.

RESULTS

A total of 528,495 patients underwent primary total hip (n = 172,467, 33%) and knee arthroplasty (n = 356,028, 67%). Of these, 3% required CCS. On average, CCS patients were older and had a higher comorbidity burden than did patients not requiring CCS. CCS patients experienced more complications, had longer hospital stays and higher costs, and were less likely to be discharged home than were non-CCS patients. Risk factors with increased odds for requiring CCS included advanced age, use of general versus neuraxial anesthesia, and the presence of postoperative cardiopulmonary complications.

CONCLUSIONS

Approximately 1 of 30 patients undergoing total joint arthroplasty requires CCS. Given the large number of these procedures performed annually, anesthesiologists, orthopedic surgeons, critical care physicians, and administrators should be aware of the attendant risks this population represents and allocate resources accordingly.

Critical care in patients undergoing lumbar spine fusion: a population-based study

BACKGROUND

Data on the utilization of critical care services (CCSs) among patients who underwent spine fusion are rare. Given the increasing popularity of this procedure, information regarding demographics and risk factors for the use of these advanced services is needed in order to appropriately allocate resources, educate clinical staff, and identify targets for future research.

METHODS

We analyzed hospital discharge data of patients who underwent lumbar spine fusion in approximately 400 US hospitals between 2006 and 2010. Patient, procedure, and health care system-related demographics for those requiring CCS were compared to those who did not. Outcomes such as mortality, complications, disposition status, and hospital charges were compared among groups and risk factors for the utilization of CCS identified.

RESULTS

A total of 95 434 entries of patients who underwent posterior lumbar spine fusion surgery between 2006 and 2010 were identified. Approximately 10% of the patients required CCS. On average, patients requiring CCS were older and had a higher comorbidity burden, developed more complications, had longer hospital stays and higher costs, and were less likely to be discharged home compared to non-CCS patients. Risk factors with increased odds for requiring CCS included advanced age, increasing comorbidity burden, increasing surgical invasiveness, and presence of postoperative complications, especially pulmonary.

CONCLUSIONS

Approximately, 10% of the patients undergoing lumbar spine surgery require CCS. Utilizing the present data, critical care physicians and administrators can identify patients at risk, educate clinical staff, identify targets for intervention, and allocate resources to meet the needs of this particular patient population.

Frequency of decreased susceptibility and resistance to echinocandins among fluconazole-resistant bloodstream isolates of Candida glabrata

The echinocandin class of antifungal agents is considered to be the first-line treatment of bloodstream infections (BSI) due to Candida glabrata. Recent reports of BSI due to strains of C. glabrata resistant to both fluconazole and the echinocandins are of concern and prompted us to review the experience of two large surveillance programs, the SENTRY Antimicrobial Surveillance Program for the years 2006 through 2010 and the Centers for Disease Control and Prevention population-based surveillance conducted in 2008 to 2010. The in vitro susceptibilities of 1,669 BSI isolates of C. glabrata to fluconazole, voriconazole, anidulafungin, caspofungin, and micafungin were determined by CLSI broth microdilution methods. Fluconazole MICs of ≥64 μg/ml were considered resistant. Strains for which anidulafungin and caspofungin MICs were ≥0.5 μg/ml and for which micafungin MICs were ≥0.25 μg/ml were considered resistant. A total of 162 isolates (9.7%) were resistant to fluconazole, of which 98.8% were nonsusceptible to voriconazole (MIC > 0.5 μg/ml) and 9.3%, 9.3%, and 8.0% were resistant to anidulafungin, caspofungin, and micafungin, respectively. There were 18 fluconazole-resistant isolates that were resistant to one or more of the echinocandins (11.1% of all fluconazole-resistant isolates), all of which contained an acquired mutation in fks1 or fks2. By comparison, there were no echinocandin-resistant strains detected among 110 fluconazole-resistant isolates of C. glabrata tested in 2001 to 2004. These data document the broad emergence of coresistance over time to both azoles and echinocandins in clinical isolates of C. glabrata.

[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.

US hospital database analysis of invasive aspergillosis in the chronic obstructive pulmonary disease non-traditional host

OBJECTIVES

Invasive aspergillosis (IA) is reported increasingly in non-traditional hosts, typically patients with chronic obstructive pulmonary disease (COPD). Objectives were to describe the excess burden of IA in COPD, including mortality, resource utilization, and costs, as well as to examine the impact of initial antifungal selection on clinical and economic outcomes.

METHODS

This retrospective cohort study used national data from 2005 to 2008, from the Premier Perspective hospital database. IA was identified using proxy ICD-9 codes based on published algorithms. The COPD + IA patient cohort was analyzed using descriptive statistics. Excess resource utilization was analyzed by matching cases (COPD + IA) and controls (COPD patients without aspergillosis) on demographic and clinical variables. Multivariate analyses were used to assess the impact of initial antifungal drug selection on outcomes in COPD + IA.

RESULTS

In total, 475 COPD + IA patients were identified (mean age 69 years, 50% male, 76% Caucasian). COPD + IA cases had significantly higher costs, length of stay, intensive care unit (ICU) stay, and mortality compared to COPD controls (all p < 0.01). On average, antifungal therapy was initiated on hospital day 6, with mean length of therapy 15 days, and one-third of patients were in the ICU when antifungal treatment was initiated. Most commonly used antifungals were voriconazole, fluconazole, and caspofungin. Patients receiving fluconazole as the initial antifungal, an agent inactive against moulds, had almost two times greater mortality (p = 0.016), two additional hospital days (p = 0.002), and 25% greater costs (p = 0.007), compared to patients receiving voriconazole first-line. Findings were consistent in sub-analyses including ICU patients.

LIMITATIONS

'Invasive' form of aspergillosis was identified using proxy ICD-9 codes based on published literature. Additional limitations stem from the study's non-randomized, retrospective design that is typical with any database analyses.

CONCLUSIONS

COPD + IA patients had significantly higher mortality, resource utilization, and costs versus COPD controls. Treatment with an agent active against Aspergillus was associated with better survival and reduced economic burden, therefore this potential etiology of pneumonia should be considered when contemplating antifungal therapy in COPD patients.

Pharmacokinetics, antifungal activity and clinical efficacy of anidulafungin in the treatment of fungal infections

IMPORTANCE OF THE FIELD

Anidulafungin is one of three available intravenous echinocandins that plays an important role in the treatment of serious fungal infections. Currently, anidulafungin is approved for the treatment of esophageal candidiasis, candidemia and other invasive Candida infections including intra-abdominal abscesses and peritonitis.

AREAS COVERED IN THIS REVIEW

This paper covers a comprehensive review of anidulafungin.

WHAT THE READER WILL GAIN

The reader will be provided the most recent data available regarding the pharmacology, pharmacokinetics, in vitro activity and clinical utility of anidulafungin for the treatment of serious fungal infections.

TAKE HOME MESSAGE

Echinocandin antifungals, such as anidulafungin, are now considered first line for the treatment of candidemia and invasive candidiasis, particularly in critically ill patients or those who have previously received azole therapy. Anidulafungin has potent in vitro activity against Candida and Aspergillus species, predictable pharmacokinetics that does not require dosage adjustment, few drug interactions and is well tolerated. Because of these favorable characteristics, anidulafungin is an important addition to our antifungal armamentarium.

Comparison of European Committee on Antimicrobial Susceptibility Testing (EUCAST) and Etest methods with the CLSI broth microdilution method for echinocandin susceptibility testing of Candida species

The antifungal broth microdilution (BMD) method of the European Committee on Antibiotic Susceptibility Testing (EUCAST) and the Etest agar diffusion method were compared with the Clinical and Laboratory Standards Institute (CLSI) BMD method M27-A3 for anidulafungin, caspofungin, and micafungin susceptibility testing of 133 clinical isolates of Candida species. The isolates were characterized for the presence or absence of fks1 and/or fks2 gene mutations and included 34 isolates of C. glabrata (4 mutant strains), 32 of C. albicans (1 mutant strain), 25 of C. parapsilosis, 19 of C. guilliermondii, 12 of C. tropicalis (2 mutant strains), and 11 of C. krusei. Excellent essential agreement (EA; within 2 dilutions) between the CLSI and EUCAST and CLSI and Etest MIC results was observed. The overall EA between the EUCAST and CLSI results ranged from 89.5% (caspofungin) to 99.2% (micafungin), whereas the EA between the Etest and CLSI results ranged from 90.2% (caspofungin) to 93.2% (anidulafungin). The categorical agreement (CA) between methods for each antifungal agent was assessed using previously determined epidemiological cutoff values (ECVs). Excellent CA (>90%) was observed for all comparisons between the EUCAST and CLSI results with the exceptions of C. glabrata and caspofungin (85.3%) and C. krusei and caspofungin (54.5%). The CA between the Etest and CLSI results was also excellent for all comparisons, with the exception of C. krusei and caspofungin (81.8%). All three methods were able to differentiate wild-type (WT) strains from those with fks mutations. With anidulafungin as the test reagent, the CLSI method identified 5 of 7 mutant strains, whereas the EUCAST method and the Etest identified 6 of 7 mutant strains. With either caspofungin or micafungin as the test reagent, the CLSI method identified all 7 mutant strains and the EUCAST method identified 6 of 7 mutant strains. The Etest identified all 7 mutant strains using caspofungin as the reagent. All three test methods showed a high level of agreement and of ability to distinguish fks mutant strains of Candida species from WT strains using each of the echinocandins.