In vitro activity of voriconazole and amphotericin B against Candida albicans, Candida krusei, and Cryptococcus neoformans in human cerebrospinal fluid.

PURPOSE: Fungal central nervous system (CNS) infections show a high mortality rate and only a few antifungal agents are available to treat these infections. We hypothesize that the different biochemical properties of human cerebrospinal fluid (CSF) compared to the standard growth medium lead to the altered activity of antifungal agents in CSF. We investigated the in vitro activity of two of these agents, i.e., amphotericin B (AmB) and voriconazole (VOR), against three different fungi in CSF in comparison to sabouraud-dextrose broth (SDB). METHODS: CSF samples from patients who did not receive any antibiotics were collected. Time-kill curves were performed in CSF and SDB using static antibiotic concentrations of AmB and VOR against ATCC strains of Candida albicans, Candida krusei, and Cryptococcus neoformans. RESULTS: In our experiments, both AmB and VOR showed superior activity in SDB compared to CSF. Nevertheless, AmB achieved fungicidal activity in CSF after 24 h against all test strains. Voriconazole only achieved fungistatic activity against C. albicans and C. neoformans in CSF. CONCLUSIONS: In summary, our data demonstrate that growth of fungal pathogens but even more importantly activity of antifungal agents against Candida and Cryptococcus species can differ significantly in CSF compared to the standard growth medium. Both findings should be taken into consideration when applying PK/PD simulations to fungal infections of the CNS.

A survey of medicine use in children and adolescents in Austria.

Aims of this survey were to evaluate prescription patterns for children and adolescents in primary and hospital care settings in Austria and to identify the medicines used most frequently in this population. Prescription data were assessed for the year 2014: for primary care, reimbursement data were obtained from Austrian health insurances; for hospital care, information on medicines dispensed to pediatric wards from hospital pharmacies. Frequencies of medicine use were analyzed by Anatomical Therapeutic Chemical classification system, age groups, and care setting. In primary care, anti-infectives (25%) and medicines for the respiratory system (14%) and for the nervous system (13%); in hospitals, anti-infectives (23%) and medicines for the nervous system (13%) and alimentary tract (12%) were prescribed most frequently. Amoxicillin/beta-lactamase inhibitor, ibuprofen, and paracetamol were the most frequent substances in both primary and hospital care settings. Based on the top 80% prescribed substances, a hit list of 150 pediatric medicines was defined for Austria. CONCLUSION: This is the first representative and comprehensive survey of medicine use in children and adolescents in Austria, allowing comparison of prescription patterns to other European countries and assessing temporal trends in the future. Moreover, it serves as basis for planned measures to improve rational use of pediatric medicines. What is Known: • Large knowledge gaps exist for medicine use in children and adolescents concerning appropriate dosing, efficacy, and safety aspects. • Off-label medicine use is common in the treatment of children and adolescents. What is New: • We present a comprehensive survey of current prescription patterns for children and adolescents in Austria and define a hit list of pediatric medicines, as basis for developing an evidence-based information platform for health care professionals. • Anti-infectives, medicines for respiratory tract system, and pain medication are most frequently prescribed.

Pharmacokinetics of doripenem in plasma and epithelial lining fluid (ELF): comparison of two dosage regimens.

PURPOSE: In 2014, FDA released a warning for prescription of doripenem for ventilator-associated bacterial pneumonia due to unsatisfactory clinical cure rates. The present study explores if the observed lack of efficacy might be explained by insufficient target site pharmacokinetics in intensive care patients after two different infusion schemes. METHODS: Plasma and bronchoalveolar lavage sampling was performed in 16 intubated patients with pneumonia receiving doripenem either as 1-h or as 4-h infusion. Doripenem concentrations were measured at steady state in plasma over 8 h, bronchoalvoelar lavage was performed in each patient once either after 0 h, 2 h, 4 h or 6 h. RESULTS: In plasma, mean values of Cmax, Tmax and AUC0-8 were 16.87 mg/L, 0.69 h and 52.98 mg/L×h after 1 h of infusion, and 12.94 mg/L, 3.21 h and 70.64 mg/L×h after 4 h of infusion, respectively. While the later tmax in plasma was with delay mirrored in the lung, for ELF, much lower concentrations were observed (Cmax, Tmax and AUC0-8 after 1-h infusion of 4.6 mg/L, 2 h and 15.3 mg/L×h and after 4-h infusion 6.9 mg/L, 4 h and 14.8 mg/L×h). CONCLUSION: The difference in plasma pharmacokinetics after 1-h and 4-h infusion reflects in the concentration versus time profile in the lung, but concentration at the target site was not only considerably lower but also subject to high inter-individual variability. We hypothesise that insufficient concentrations at the target site might have contributed to the previously described lack of clinical efficacy and confirmed the demand for assessment of target site pharmacokinetics in larger patient collectives.

Understanding the Activity of Antibiotics in Cerebrospinal Fluid in vitro.

BACKGROUND: In vitro studies suggest that antimicrobial activity of antibiotics meant to treat central nervous system infections such as meningitis or ventriculitis may be altered by cerebrospinal fluid (CSF). This could explain the reason behind the often observed discrepancies between the activity of antibiotics determined in artificial growth media in vitro, and their sometimes reduced clinical efficacy in CSF in vivo. If conducted in CSF, in vitro microbiological investigations might predict the ability of antibiotic drugs to treat CSF infections better than experiments in artificial growth media. In addition, they are less expensive, critical and time consuming than animal studies, and might potentially be appreciated in drug development as a rapid and cost-effective means to gain valuable information on drugs meant to treat infections residing in CSF. SUMMARY: Data from microbiological in vitro experiments performed in CSF were compiled for fosfomycin, rifampicin, cefepime, cefotaxime, ceftriaxone, ciprofloxacin, gentamicin and vancomycin. Where possible, correlations between in vitro data and evidence from in vivo studies were established. KEY MESSAGES: As discussed in the text, no clear correlations between in vitro studies in CSF and clinical outcomes could be identified. Methodological recommendations derived from the collected studies are summarized in order to optimize future research on the topic.

Acetylic Salicylic Acid for the Treatment of Chronic Obstructive Pulmonary Disease: A Randomized, Double-Blind, Placebo-Controlled Trial.

PURPOSE: Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death in the world. Current treatment options provide relief from symptoms rather than stop disease progress. Results from various preclinical experiments suggest a causal benefit of acetylic salicylic acid (ASA) in the treatment of COPD. Hence, this study set out to examine the clinical benefit of ASA in the treatment of COPD. COPD patients (Global Initiative for Chronic Obstructive Lung Disease II-III) received either once daily 500 mg of ASA or a matching placebo for 12 weeks in addition to their preexisting medication. Clinical response in terms of pulmonary function testing, symptomatic response and adverse events were assessed. After 40 subjects were included, the study was stopped and an interim analysis was performed. The addition of ASA to the treatment of subjects with COPD had no effect on clinical features or spirometry (forced expiratory volume in 1 s: F = 0.49, d.f.1 = 1, d.f.2 = 74, p = 0.486) and non-pulmonary markers. COPD represents a complex of different diseases, although currently classified mainly by markers of lung function. If future trials test the effects of anti-inflammatory therapies, COPD subpopulations should be predefined based on inflammatory features.

[Polypharmacy--activities of the social insurance in Austria]. / Polypharmazie--Aktivitäten der österreichischen Sozialversicherung.

In Austria, about a quarter of the population older than 60 years receives more than five medicines per quarter at the expense of the statutory health insurance. Especially for older and multimorbid people the risk of adverse drug reactions increases by taking multiple drugs. The social insurance has initiated activities to direct the focus on the issue of polypharmacy and the associated problems. An information campaign with the title "Vorsicht Wechselwirkung" has been developed which addresses physicians and patients. Tailored to the target groups, useful information and assistance should contribute to strengthening the awareness and compliance, and to improving the quality of drug therapies. To specifically sensitize general practitioners to the issue of polypharmacy, the "Poly-rate" is calculated. It is used as a parameter to assess the extent of polypharmacy in a physician's practice, and is being sent to general practitioners by the social insurance for information purposes.

Tissue pharmacokinetics of ertapenem at steady-state in diabetic patients with leg infections.

OBJECTIVES: Ertapenem pharmacokinetics were determined in the interstitium of healthy tissue and of infected tissue of patients suffering from diabetic foot infections, to evaluate if antibiotic concentrations at the target site are sufficient to achieve bacterial killing. PATIENTS AND METHODS: Nine patients with diabetic foot infections received 1 g of ertapenem per day intravenously. At steady-state, ertapenem concentrations were measured over 8 h in plasma and in the interstitium of healthy subcutaneous adipose tissue and of soft tissue adjacent to the foot infection using microdialysis. RESULTS: The maximum total concentration (Cmax) of ertapenem in plasma was 59.4 ± 12.9 mg/L. Free interstitial Cmax in the infected leg (4.5 ± 2.7 mg/L) was significantly higher (P=0.01) than in healthy subcutaneous tissue (2.4 ± 1.6 mg/L). For bacterial pathogens with an MIC of 1 mg/L, the free mean 'time above MIC' (T>MIC) in the interstitium of infected tissue was calculated to be 38%± 25% of the 24 h dosing interval. Accordingly, bacteriostatic (T>MIC >20%) and maximal bactericidal (T>MIC >40%) effects would be reached in 8/9 and 4/9 diabetic feet, respectively. CONCLUSIONS: Although total plasma concentrations of ertapenem were lower in diabetics than reported for healthy subjects, free interstitial tissue concentrations in diabetics were similar to those known from healthy volunteers. Penetration of ertapenem into the interstitium of inflamed tissue of diabetic feet was not impaired in spite of angiopathy. Daily doses of >1 g of ertapenem might be considered to optimize bactericidal effects in diabetic foot infections caused by moderately susceptible strains.

Corrigendum to "Utilisation Trend of Long-Acting Insulin Analogues including Biosimilars across Europe: Findings and Implications".

[This corrects the article DOI: 10.1155/2021/9996193.].

Penetration of doripenem into skeletal muscle and subcutaneous adipose tissue in healthy volunteers.

Sufficient antibiotic concentrations at the infection site are a prerequisite for good bacterial killing. This study was performed to determine pharmacokinetics of doripenem in soft tissues and saliva. Six healthy male volunteers received a single intravenous infusion of 500 mg doripenem over 1 h. The concentrations of doripenem were measured over 8 h in saliva, plasma, and extracellular space fluid of skeletal muscle and subcutaneous adipose tissue employing in vivo microdialysis. Unbound drug concentrations were determined using ultra-high-performance liquid chromatography-tandem mass spectrometry. Maximum concentrations of doripenem were 15.3 ± 6.0 mg/liter in plasma, 9.9 ± 2.3 mg/liter in subcutaneous adipose tissue, 6.6 ± 2.9 mg/liter in skeletal muscle, and 0.5 ± 0.2 mg/liter in saliva. Areas under the concentration-time curve (AUC) from 0 to infinity were 26.3 ± 10.1, 20.4 ± 3.8, 12.8 ± 3.0, and 1.0 ± 0.5 mg · h/liter in plasma, adipose tissue, skeletal muscle, and saliva, respectively. Ratios of AUC in adipose tissue, skeletal muscle, and saliva to those in plasma were 0.84 ± 0.28, 0.53 ± 0.19, and 0.04 ± 0.03, respectively. In all six volunteers, a threshold of ≥40% for "time above MIC," an index indicative of good antimicrobial activity, was exceeded in adipose tissue for MICs of ≤2 mg/liter and in skeletal muscle for MICs ≤1.5 mg/liter. Doripenem penetrates well into interstitial space fluid of skeletal muscle and adipose tissue, suggesting good antimicrobial activity in infected soft tissues, whereas it is detectable in relatively low concentrations in saliva.

Abscess penetration of cefpirome: concentrations and simulated pharmacokinetic profiles in pus.

PURPOSE: Abscess patients frequently receive antibiotic therapy when incision cannot be performed or in addition to incision. However, antibiotic concentrations in human abscesses are widely unknown. METHODS: Pharmacokinetics of cefpirome in 12 human abscesses located in different body regions was studied. Cefpirome (2 g) was administered as an intravenous short infusion, and concentrations were measured in plasma over an 8-h period and in abscesses at incision. A pharmacokinetic two-stage model was applied. RESULTS: At abscess incision performed 158 ± 112 min after the start of the infusion, the cefpirome concentrations in the abscess fluid varied markedly, ranging from ≤0.1 (limit of quantification) to 47 (mean 8.4 ± 14.1 ) mg/L. Cefpirome was detectable in nine of 12 abscesses. Maximum concentrations were calculated to be 183 ± 106 mg/L in plasma and 12 ± 16 mg/L in the abscess. A cefpirome concentration of 2 mg/L, which is the minimum concentration inhibiting growth of 90% of the most relevant bacterial pathogens, was exceeded spontaneously in six of 12 abscesses after a single dose. Cefpirome concentrations in the abscess did not correlate with either the pH or the ratio of surface area to volume of the abscesses, nor with plasma pharmacokinetics. CONCLUSIONS: Cefpirome may be useful to treat abscess patients because it was detectable in most abscesses after a single dose. However, the penetration of cefpirome into abscesses is extremely variable and cannot be predicted by measuring other available covariates.

Good penetration of moxifloxacin into human abscesses.

Abscesses are often treated with antibiotics in addition to incision or when incision is unfeasible, but accurate information about antibiotic abscess penetration in humans is missing. This study aimed at evaluating the penetration of moxifloxacin into human abscesses. After administration of a single dose of 400 mg moxifloxacin, drug concentrations were measured in 10 differently located abscesses at incision, and in plasma over 8 h. At incision performed 0.9-4.8 h after administration, moxifloxacin concentrations in abscesses ranged from ≤0.01 to 9.2 mg/l (1.9 ± 3.4 mg/l), indicating pronounced drug accumulation in some abscesses. The degree of abscess penetration could not be explained by covariates like the ratio of surface area to volume or pH of abscesses, or by moxifloxacin plasma concentrations. Concluding, moxifloxacin was detectable in most abscesses and may be a useful antibiotic for this indication. However, antibiotic abscess penetration was highly variable and unpredictable, suggesting surgical abscess incision whenever possible.

Ramipril modulates circadian gene expression in skeletal muscle.

OBJECTIVES: Treatment with angiotensin converting enzyme (ACE)-inhibitors favorably affects glucose metabolism and the development of diabetes mellitus by largely elusive mechanisms. To identify these mechanisms, we studied the effect of ACE-inhibition on gene expression in skeletal muscle, a primary target tissue for insulin in glucose homeostasis. METHODS: A subject-blinded and analyst-blinded, placebo-controlled study was conducted in nine healthy men. Two consecutive muscle biopsies were conducted before and 9 h after a single dose of either 10-mg ramipril (n=6) or placebo (n=3), (randomly allocated). Muscle ribonucleic acid was subjected to transcriptome profiling. RESULTS: In both ramipril-treated or placebo-treated individuals, the majority of genes with differential expression between the two time points belonged to the family of diurnally regulated genes, such as the NR1D1 and NR1D2 genes (nuclear receptor subfamily 1, group D, members 1 and 2) or members of the period homolog family (PER1-3). Ramipril significantly modulated the expression of other diurnally regulated genes, such as aryl hydrocarbon receptor nuclear translocator-like (ARNTL), encoding aryl hydrocarbon receptor nuclear translocator-like, a core component of the circadian clock (P=0.02). Concomitant attenuation of NR1D1 downregulation (-2.4-fold compared with -4.1-fold in placebo; P=0.04), a transcriptional repressor of ARNTL, supported the view that ramipril might modulate glucose homeostasis pathways involving the NR1D1 ARNTL axis. CONCLUSION: As circadian rhythms are deranged in patients who are diabetic, modulated expression of circadian clock genes by ramipril could explain the favorable metabolic effects of therapeutic ACE-inhibition.

Assessing the Accuracy of Sales Forecasts Submitted by Pharmaceutical Companies Applying for Reimbursement in Austria.

Objectives: Reimbursement decisions on new medicines require an assessment of their value. In Austria, when applying for reimbursement of new medicines, pharmaceutical companies are also obliged to submit forecasts of future sales. We systematically examined the accuracy of these pharmaceutical sales forecasts and hence the usefulness of these forecasts for reimbursement evaluations. Methods: We retrospectively analyzed reimbursement applications of 102 new drugs submitted between 2005 and 2014, which were accepted for reimbursement outside of hospitals, and for which actual reimbursed sales were available for at least 3 years. The main outcome variable was the accuracy ratio, defined as the ratio of forecasted sales submitted by pharmaceutical companies when applying for reimbursement to actual sales from reimbursement data. Results: The median accuracy ratio [95% confidence interval] was 1.33 [1.03; 1.74, range 0.15-37.5], corresponding to a median overestimation of actual sales by 33%. Forecasts of actual sales for 55.9% of all examined products either overestimated actual sales by more than 100% or underestimated them by more than 50%. The accuracy of sales forecasts did not show systematic change over the analyzed decade nor was it discernibly influenced by reimbursement status (restricted or unrestricted), the degree of therapeutic benefit, or the therapeutic area of the pharmaceutical product. Sales forecasts of drugs with a higher degree of innovation and those within a dynamic market tended to be slightly more accurate. Conclusions: The majority of sales forecasts provided by applicants for reimbursement evaluations in Austria were highly inaccurate and were on average too optimistic. This is in line with published results for other jurisdictions and highlights the need for caution when using such forecasts for reimbursement procedures.

Potential approaches for the pricing of cancer medicines across Europe to enhance the sustainability of healthcare systems and the implications.

Introduction: There are growing concerns among European health authorities regarding increasing prices for new cancer medicines, prices not necessarily linked to health gain and the implications for the sustainability of their healthcare systems.Areas covered: Narrative discussion principally among payers and their advisers regarding potential approaches to the pricing of new cancer medicines.Expert opinion: A number of potential pricing approaches are discussed including minimum effectiveness levels for new cancer medicines, managed entry agreements, multicriteria decision analyses (MCDAs), differential/tiered pricing, fair pricing models, amortization models as well as de-linkage models. We are likely to see a growth in alternative pricing deliberations in view of ongoing challenges. These include the considerable number of new oncology medicines in development including new gene therapies, new oncology medicines being launched with uncertainty regarding their value, and continued high prices coupled with the extent of confidential discounts for reimbursement. However, balanced against the need for new cancer medicines. This will lead to greater scrutiny over the prices of patent oncology medicines as more standard medicines lose their patent, calls for greater transparency as well as new models including amortization models. We will be monitoring these developments.

Utilisation Trend of Long-Acting Insulin Analogues including Biosimilars across Europe: Findings and Implications.

BACKGROUND: Diabetes mellitus rates and associated costs continue to rise across Europe enhancing health authority focus on its management. The risk of complications is enhanced by poor glycaemic control, with long-acting insulin analogues developed to reduce hypoglycaemia and improve patient convenience. There are concerns though with their considerably higher costs, but moderated by reductions in complications and associated costs. Biosimilars can help further reduce costs. However, to date, price reductions for biosimilar insulin glargine appear limited. In addition, the originator company has switched promotional efforts to more concentrated patented formulations to reduce the impact of biosimilars. There are also concerns with different devices between the manufacturers. As a result, there is a need to assess current utilisation rates for insulins, especially long-acting insulin analogues and biosimilars, and the rationale for patterns seen, among multiple European countries to provide future direction. Methodology. Health authority databases are examined to assess utilisation and expenditure patterns for insulins, including biosimilar insulin glargine. Explanations for patterns seen were provided by senior-level personnel. RESULTS: Typically increasing use of long-acting insulin analogues across Europe including both Western and Central and Eastern European countries reflects perceived patient benefits despite higher prices. However, activities by the originator company to switch patients to more concentrated insulin glargine coupled with lowering prices towards biosimilars have limited biosimilar uptake, with biosimilars not currently launched in a minority of European countries. A number of activities were identified to address this. Enhancing the attractiveness of the biosimilar insulin market is essential to encourage other biosimilar manufacturers to enter the market as more long-acting insulin analogues lose their patents to benefit all key stakeholder groups. CONCLUSIONS: There are concerns with the availability and use of insulin glargine biosimilars among European countries despite lower costs. This can be addressed.

Cerebrospinal fluid impairs antimicrobial activity of fosfomycin in vitro.

OBJECTIVES: Fosfomycin penetrates well into cerebrospinal fluid (CSF) and is considered for treatment of infections of the central nervous system (CNS). This study evaluated the influence of human CSF on the antimicrobial activity of fosfomycin. METHODS: Time-kill curves were performed in Mueller-Hinton broth (MHB) and in pooled human CSF using fosfomycin concentrations ranging from 0.25x to 8x MIC for a clinical Staphylococcus aureus isolate. To estimate the activity of fosfomycin at the target site, the concentration-time curve measured in CSF of a patient at steady state was simulated in vitro in human CSF using two S. aureus isolates. RESULTS: In CSF a higher fosfomycin concentration (8x MIC) was required to achieve sustained bacterial killing than in MHB (1x MIC). In vitro simulation of the pharmacokinetic profile measured in CSF of the selected patient showed initial killing, but terminal re-growth of both test strains. CONCLUSIONS: The antibacterial activity of fosfomycin is lower in CSF than in MHB, and drug concentrations slightly exceeding the MIC may not be sufficient to achieve bactericidal effects in the CNS.

Pharmacokinetics and safety of intrathecal liposomal cytarabine in children aged <3 years.

BACKGROUND AND OBJECTIVE: Liposomal cytarabine (DepoCyte) is a slow-release formulation for intrathecal application, ensuring prolonged drug exposure. Although there is an urgent need for new treatment options for infants with leptomeningeal dissemination of a malignant brain tumour, there are no clinical and pharmacokinetic data available on this drug for children aged <3 years. The objective of this pilot study was to determine the feasibility, safety and pharmacokinetics of cytarabine after intrathecal administration of liposomal cytarabine 25 mg in patients aged <3 years. PATIENTS AND METHODS: Six male patients with a mean age of 21 months and CNS primitive neuroectodermal tumours (n = 3) or atypical teratoid/rhabdoid tumours (n = 3) were included. Liposomal cytarabine (25 mg) was administered intraventricularly. One patient also received the drug by lumbar puncture. Dexamethasone was used concomitantly for 3-5 days to prevent arachnoiditis. Cerebrospinal fluid (CSF) and plasma samples were collected before administration of liposomal cytarabine and 1 hour, 12 hours, 24 hours, 1 week and 2 weeks post-dosing. Noncompartmental pharmacokinetic analysis of CSF and plasma was performed. RESULTS: Liposomal cytarabine was generally well tolerated; only grade 2 headache occurred in one patient. After intraventricular administration of cytarabine 25 mg, free and encapsulated drug concentrations above the cytotoxic drug level of 0.1 microg/mL were detectable in the CSF for at least 7 days and up to 14 days post-dosing. The average elimination half-lives were 56.7 hours for encapsulated cytarabine and 59.3 hours for free cytarabine. After intralumbar administration, the elimination half-life of free cytarabine, measured in the ventricular CSF during two courses in one patient, was significantly shorter (32.7 hours). CONCLUSION: Application of liposomal cytarabine with concomitant dexamethasone appears to be safe and well tolerated in children aged <3 years. Drug exposure in infants aged <3 years after an intraventricular dose of 25 mg is comparable to that after administration of 50 mg in adult patients and 35 mg in older children.

Proposal for a regulation on health technology assessment in Europe - opinions of policy makers, payers and academics from the field of HTA.

INTRODUCTION: In January 2018 the European Commission published a Proposal for a Regulation on Health Technology Assessment (HTA): 'Proposal for a Regulation on health technology assessment and amending Directive 2011/24/EU'. A number of stakeholders, including some Member States, welcomed this initiative as it was considered to improve collaboration, reduce duplication and improve efficiency. There were however a number of concerns including its legal basis, the establishment of a single managing authority, the preservation of national jurisdiction over HTA decision-making and the voluntary/mandatory uptake of joint assessments by Member States. Areas covered: This paper presents the consolidated views and considerations on the original Proposal as set by the European Commission of a number of policy makers, payers, experts from pricing and reimbursement authorities and academics from across Europe. Expert commentary: The Proposal has since been extensively discussed at Council and while good progress has been achieved, there are still divergent positions. The European Parliament gave a number of recommendations for amendments. If the Proposal is approved, it is important that a balanced, improved outcome is achieved for all stakeholders. If not approved, the extensive contribution and progress attained should be sustained and preserved, and the best alternative solutions found.

Effects of olanzapine and ziprasidone on glucose tolerance in healthy volunteers.

Atypical antipsychotics have been linked to a higher risk for glucose intolerance, and consequentially the development of type 2 diabetes mellitus (DM2). We have therefore set out to investigate the acute effects of oral administration of olanzapine and ziprasidone on whole body insulin sensitivity in healthy subjects. Using the standardized hyperinsulinemic euglycemic clamp technique we compared whole body insulin sensitivity of 29 healthy male volunteers after oral intake of either olanzapine 10 mg/day (n = 14) or ziprasidone 80 mg/day (n = 15) for 10 days. A significant decrease (p<0.001) in whole body insulin sensitivity from 5.7 ml/h/kg ( = mean, SM = 0.4 ml/h/kg) at baseline to 4.7 ml/h/kg ( = mean, SM = 0.3 ml/h/kg) after oral intake of olanzapine (10 mg/day) for 10 days was observed. The ziprasidone (80 mg/day) group did not show any significant difference (5.2+/-0.3 ml/h/kg baseline vs 5.1+/-0.3 ml/h/kg) after 10 days of oral intake. Our main finding demonstrates that oral administration of olanzapine but not ziprasidone leads to a decrease in whole body insulin sensitivity in response to a hyperinsulinemic euglycemic challenge. Our finding is suggestive that not all atypical antipsychotics cause acute direct effects on glucose disposal and that accurate determination of side effect profile should be performed when choosing an atypical antipsychotic.

Plasma protein binding of fluoroquinolones affects antimicrobial activity.

OBJECTIVES: In contrast to most antimicrobial classes, there is a doubt about the impact of protein binding (PB) on the antimicrobial activity of fluoroquinolones. We set out to evaluate the suitability of previously used models for investigating the influence of PB on bacterial killing by fluoroquinolones. METHODS: PB of moxifloxacin and trovafloxacin was determined in Mueller-Hinton broth (MHB) containing different concentrations of human serum or albumin. Bacterial growth curves of Staphylococcus aureus and Pseudomonas aeruginosa were determined in pure serum, pure MHB and MHB containing different amounts of serum or albumin. Killing of both strains at concentrations equal to the MIC was investigated for moxifloxacin and trovafloxacin in MHB and also in medium that showed PB values identical to those of pure serum. RESULTS: Frequently used media for investigating the impact of PB, i.e. MHB containing 20% to 70% serum or 4% albumin, did not reach the level of PB achieved in pure serum or significantly hampered bacterial growth compared with pure MHB. PB in MHB containing 12% albumin was identical to that in pure serum but did not impair bacterial growth. Addition of 12% albumin significantly reduced bacterial killing by both fluoroquinolones compared with that found in pure MHB. CONCLUSIONS: For fluoroquinolones, standard media might be insufficient to investigate the impact of PB on bacterial killing. MHB containing 12% albumin seems to be a promising medium in this context. For moxifloxacin and trovafloxacin, PB leads to significant reduction of antimicrobial activity.