Long-term add-on therapy (compassionate use) with oral artesunate in patients with metastatic breast cancer after participating in a phase I study (ARTIC M33/2).

BACKGROUND: The antimalarial artesunate (ART), a semisynthetic derivative of artemisinin from the Chinese herb artemisia annua has remarkable anticancer properties in vitro and in vivo. Its excellent safety profile known from short-term therapy in malaria was confirmed in an open phase I trial (ARTIC M33/2) for dose-finding as add-on therapy for four weeks. PURPOSE: Patients with metastatic breast cancer, who had not experienced any clinically relevant adverse events (AE) during participation in ARTIC M33/2, were offered to continue ART as compassionate use (CU). Regular monitoring was continued in order to ensure adequate individual safety and tolerability and to collect information about long-term treatment with ART. Clinically relevant AEs or second progression of disease during ART were reasons for discontinuation of the add-on therapy. STUDY DESIGN: Compassionate use was offered open-label to participants of ARTIC M33/2. METHODS: Patients continued to take 100, 150 or 200 mg oral ART daily as add-on therapy to their guideline-based oncological therapy. Clinical and laboratory monitoring included audiological and neurological examination, ECG, NTproBNP and reticulocyte determination. Cumulative treatment days and cumulative ART doses encompass both the phase I study as well as the continued add-on treatment period (CU). RESULTS: Following the 4 ±â€¯1 weeks of the phase I trial, thirteen patients continued the add-on therapy as CU, resulting in a total of 3825 treatment days. In individual patients up to 1115 cumulative treatment days (37 months) and cumulative ART doses up to 167.3 g were reached. A total of 25 AEs grade ≥ 2 at least possibly related to ART long-term add-on therapy were documented, two, six and 17 in dose groups 100, 150 and 200 mg/d ART respectively. Six of these AEs were classified as grade 3, two in patients taking 150 and four in patients on 200 mg/d, none of them being probably or certainly related to ART. CONCLUSIONS: In thirteen patients with metastatic breast cancer up to 200 mg/d long-term oral ART (2.3-4.1 mg/kg BW/d) in up to 1115 cumulative treatment days (37 months) did not result in any major safety concerns.

Prospective open uncontrolled phase I study to define a well-tolerated dose of oral artesunate as add-on therapy in patients with metastatic breast cancer (ARTIC M33/2).

PURPOSE: The antimalarial drug artesunate (ART) is a promising candidate for cancer treatment as it displays anticancer effects in various models. While in short-term treatment of malaria, an excellent safety profile has been found for ART, the potential long-term treatment of cancer patients demands a phase I dose-finding clinical trial determining the daily ART dose which would be well tolerated as add-on therapy. METHODS: Patients with metastatic breast cancer were to receive either 100 or 150 or 200 mg oral ART daily as add-on to their guideline-based oncological therapy for a study period of four weeks with frequent clinical and laboratory monitoring until 4-8 weeks thereafter. According to the statistical design, recruitment was scheduled in groups of three patients in order not to miss a more than 33% frequency of dose-limiting adverse events (DL-AE) prior to dose escalation. RESULTS: Twenty-three patients were recruited, and all planned dose levels were applied. During the actual trial period of 4 ± 1 weeks, three patients experienced six DL-AEs altogether (leucopenia, neutropenia, asthenia, anemia) possibly related to ART (not exceeding 33% in any dose level). CONCLUSIONS: Up to 200 mg/d (2.2-3.9 mg/kg/d) oral ART were safe and well tolerated; therefore, 200 mg/d are recommended for phase II/III trials. Safety monitoring should include reticulocytes, NTproBNP, as well as audiological and neurological exploration.

Investigation of ototoxicity of artesunate as add-on therapy in patients with metastatic or locally advanced breast cancer: new audiological results from a prospective, open, uncontrolled, monocentric phase I study.

PURPOSE: Artesunate (ART) has been used for a long time in the treatment of Plasmodium falciparum malaria and has been considered safe. The present phase I study aimed to determine the daily dose of ART that is well tolerated as add-on therapy in patients with breast cancer for 4 weeks of therapy. Ototoxicity could be a potential safety concern in settings different from malaria. Therefore, comprehensive audiological assessment was essential. METHODS: The ARTIC M33/2 study was a prospective, open, uncontrolled, monocentric phase I dose-escalation study to evaluate the safety and tolerability of ART in patients with advanced breast cancer. Patients received either 100, 150 or 200 mg oral ART daily for a test phase of 4 weeks as add-on therapy to their ongoing oncological treatment. For the investigation of the safety of ART for hearing, an audiological assessment was performed with each patient before the intake of ART and after 4 weeks of therapy. RESULTS: Twenty-three female patients were included in the study. During the test phase, four patients had adverse events (AEs) of the auditory system possibly related to the intake of ART. However, none of these AEs was classified as severe AE (SAE) and did not require treatment interruption. Four patients had AEs concerning the vestibular system (vertigo) during the test phase, one of which was classified as SAE. However, the SAE was fully reversible after discontinuation of ART. CONCLUSION: None of the audiological results after 4 weeks of therapy with ART showed any dose-limiting auditory toxicity. However, audiological monitoring in further clinical studies with prolonged use of oral ART in doses up to 200 mg daily is warranted. The ARTIC M33/2 study is registered at eudract.ema.europa.eu with the Number 2007-004432-23 and at clinicaltrials.gov with the Number NCT00764036.

Haemolysis risk in methylene blue treatment of G6PD-sufficient and G6PD-deficient West-African children with uncomplicated falciparum malaria: a synopsis of four RCTs.

PURPOSE: Methylene blue (MB), which was recently tested in a number of clinical malaria studies in Burkina Faso, is currently investigated for its benefit when added to artemisinin-based combination therapy. Together with a number of other antimalarials, MB is on the list of drugs which potentially induce haemolysis in patients with G6PD deficiency. Ruling out safety concerns is of major importance during drug development. METHODS: A pooled analysis was performed with patient data from four clinical studies conducted in West African children with falciparum malaria between 2003 and 2007. The primary endpoints were haemoglobin levels over time as well as haemolysis in G6PD-deficient (n = 199) and G6PD-sufficient (n = 806) children treated with MB-containing (n = 844) compared to children without MB-containing (n = 161) drug regimens. RESULTS: In the chosen model, the haemoglobin time course was significantly influenced by the G6PD genotype and the MB dose. In children with hemi- or homozygous G6PD (A-) deficiency, MB treatment with 15 mg/kg per day was associated with a significant reduction in Hb values which reached a minimum of 8.5 g/dl. Two episodes of haemolysis occurred (out of 1005 children); one in a girl heterozygous for G6PD deficiency and one in a hemizygous boy, both had received MB. CONCLUSIONS: MB treatment of malaria in Africa is associated with slightly reduced haemoglobin values in children with a full G6PD defect compared to non-G6PD deficient children. This effect appears to be of limited clinical relevance but needs to be monitored.

Objective assessment of nonadherence and unknown co-medication in hospitalized patients.

PURPOSE: The intake of medications (drugs) without the knowledge of the treating physician (unknown co-medication) and nonadherence strongly influence drug safety. The aim of our study was to objectively assess unknown co-medication and nonadherence in hospitalized patients by screening urine for a large number of drugs using highly sensitive full scan gas chromatograpy/mass spectrometry (GC/MS). Secondary objectives were to determine the relationship of co-medication and nonadherence to the number of drugs prescribed and to compare history-taking by a pharmacist versus a physician. METHODS: In 152 patients, the drug histories taken by physicians, patients' self-reported adherence, and information compiled during as many as three structured interviews conducted by a trained pharmacist on days 1-2, 3-4, and 7-11 of the hospital stay were compared with the GC/MS results from urine samples collected after each interview. RESULTS: In the interviews performed by the pharmacist, 235 additional drugs were identified that were not documented in the chart. Of all the drugs indicated in any interview, 16.9% were identified only by the physician, 24.1% only by the pharmacist, and 59% by both. Overall, in 78% of the patients at least one additional drug was identified by urine screening. The findings suggest overall nonadherence to at least one drug in 13.0% of patients on admission and in 23.3% of patients at any time during hospitalization. Nonadherence was less frequent for critical dose drugs and correlated with the number of prescribed drugs. CONCLUSIONS: The drug history among hospitalized patients is often incomplete, and nonadherence and unknown co-medication are alarmingly frequent. This lack of knowledge might impact the overall success of drug therapies in the hospital setting.

Efficacy of methylene blue monotherapy in semi-immune adults with uncomplicated falciparum malaria: a controlled trial in Burkina Faso.

OBJECTIVE: To assess the efficacy of methylene blue (MB) monotherapy in semi-immune adults with uncomplicated malaria in Burkina Faso. METHODS: In an open-label controlled phase II study with 60 semi-immune adults with uncomplicated falciparum malaria in Nouna, north-western Burkina Faso, MB monotherapy (390 mg twice daily) was given sequentially to groups of 20 adults for 7 days (MB7), 5 days (MB5) and 3 days (MB3), respectively. The primary outcome was the rate of adequate clinical and parasitological response (ACPR) on day 28 of follow-up. RESULTS: Of the study population, 27/58 (47%) and 5/51 (10%) patients still had parasites on days 2 and 3, respectively, of follow-up resulting in 9/58 (16%) early treatment failures. By day 14, no recrudescence was observed but in 4/19 (MB5) and 2/20 (MB3) individuals by day 28. The PCR-corrected rate of ACPR was 72%, 58% and 85% in groups 7, 5 and 3, respectively, by per protocol analysis. Self-limiting dysuria was the most frequent adverse event. CONCLUSIONS: MB acts slowly against the blood stages of P. falciparum. MB alone needs to be given for at least 7 days to be efficacious in the treatment of falciparum malaria but should be used in combination with a fast acting antimalarial.

Prevention of adverse drug reactions in intensive care patients by personal intervention based on an electronic clinical decision support system.

OBJECTIVE: We investigated the effect of written drug information for senior clinicians on the incidence of drug-drug interactions (DDIs) and DDI-related adverse events in intensive care patients. DESIGN AND METHODS: A prospective controlled intervention cohort study was conducted in a medical intensive and intermediate care unit in a university hospital. From 1,062 consecutive intensive care patients, those 265 (control: 136, intervention: 129) with > or =8 concurrently prescribed drugs were included in the study (to include high-risk patients with polypharmacy). The DDI information for senior clinicians during an intervention period of 3 months was based on a computerised clinical decision support system (CDSS) containing information on risk and management of 9,453 drug combinations. RESULTS: The number of patients with at least one DDI at the end of the respective study phase decreased by 18% (relative risk reduction) from 90 (66%) patients in controls to 70 (54%) in the intervention group (p = 0.02). The relative risk of a patient suffering from at least one DDI-related adverse event decreased by 43% from 60 (44%) patients in controls to 32 (25%) in the intervention group (p < 0.01). Among these events, the incidence of QT(C) prolongation was reduced by 64% from 15 (11%) patients in the control group to 5 (4%) in the intervention group (p = 0.04), and the incidence of hypokalemia by 80% from 14 (10%) to 2 (2%, p < 0.01). CONCLUSION: Written drug information based on a CDSS considerably decreased DDIs and DDI-related adverse events in routine practice.

Successful strategy to improve the specificity of electronic statin-drug interaction alerts.

PURPOSE: A considerable weakness of current clinical decision support systems managing drug-drug interactions (DDI) is the high incidence of inappropriate alerts. Because DDI-induced, dose-dependent adverse events can be prevented by dosage adjustment, corresponding DDI alerts should only be issued if dosages exceed safe limits. We have designed a logical framework for a DDI alert-system that considers prescribed dosage and retrospectively evaluates the impact on the frequency of statin-drug interaction alerts. METHODS: Upper statin dose limits were extracted from the drug label (SPC) (20 statin-drug combinations) or clinical trials specifying the extent of the pharmacokinetic interaction (43 statin-drug combinations). We retrospectively assessed electronic DDI alerts and compared the number of standard alerts to alerts that took dosage into account. RESULTS: From among 2457 electronic prescriptions, we identified 73 high-risk statin-drug pairs. Of these, SPC dosage information classified 19 warnings as inappropriate. Data from pharmacokinetic trials took quantitative dosage information more often into consideration and classified 40 warnings as inappropriate. This is a significant reduction in the number of alerts by 55% compared to SPC-based information (26%; p < 0.001). CONCLUSION: This retrospective study of pharmacokinetic statin interactions demonstrates that more than half of the DDI alerts that presented in a clinical decision support system were inappropriate if DDI-specific upper dose limits are not considered.

CYP2C19 genotype is a major factor contributing to the highly variable pharmacokinetics of voriconazole.

In vitro data on the metabolism of the antifungal voriconazole suggest that its pharmacokinetics might be influenced by the activity of CYP2C19, CYP2C9, and CYP3A. To elucidate the genetic influence of polymorphic enzymes on voriconazole metabolism, the authors pooled the pharmacokinetic data from 2 interaction studies in which 35 participants were enrolled according to their CYP2C19 genotype to receive a single 400-mg oral dose of voriconazole. Nine participants were homozygous for CYP2C19(*)1/(*)1, 8 heterozygous for (*)1/(*)17, 11 heterozygous for (*)1/(*)2, 2 heterozygous for (*)2/(*)17, 4 homozygous for (*)2/(*)2, and 1 with a double mutation CYP2C19(*)2/(*)2(*)17. Nine (heterozygous) individuals were carriers of the CYP2C9(*)2 or (*)3 variant alleles. Twenty-five participants did not express the CYP3A5 isozyme ((*)3/(*)3), whereas in 5 individuals, the (*)1/(*)3 combination was present (active enzyme). In addition, the CYP2D6 genotype and 2 variants of the drug transporter MDR1 (C3435T and G2677T) were determined. Multiple regression analysis of voriconazole apparent oral clearance revealed that 49% of its variance can be explained solely by the CYP2C19 polymorphism (P < .0001). Including the other polymorphisms into the regression model did not show any significant contribution. The number of variant CYP2C19 alleles therefore explains a substantial part of the wide variability of voriconazole pharmacokinetics, whereas the presence of functional CYP3A5 and the CYP2C9 genotype had no significant impact on voriconazole exposure. Some minor contribution results from the MDR1 C3435T genotype.

High absolute bioavailability of methylene blue given as an aqueous oral formulation.

PURPOSE: Methylene blue (MB) has recently been reevaluated for malaria treatment. With the aim of excluding treatment failures due to low bioavailability, we have investigated the absolute bioavailability of MB given as an aqueous oral formulation and its interaction with chloroquine (CQ). METHODS: A phase I study in 16 healthy individuals was performed as a monocenter prospective open randomized intra-individual cross-over comparison of MB single doses [50 mg intravenous (i.v.), 500 mg orally, separated by a 1-week wash-out]. After a second week, the group was split for a randomized parallel group comparison of CQ 750 mg administered orally alone or combined with 500 mg MB orally. RESULTS: Mean MB plasma area under the substrate concentration-time curve (AUC 0-infinity) was 7,639 +/- 3,384 ng/mL*h and 51,171 +/- 17,147 ng/mL*h after i.v. and oral administration, respectively (dosage 1:10), and 76,897 +/- 46,037 ng/mL*h after MB combined with CQ. The absolute bioavailability was 72.3 +/- 23.9%. Co-administration with CQ significantly increased MB plasma concentrations (p

[Particularities of drug dosing at the beginning and end of therapy]. / Dosierungsbesonderheiten am Anfang und Ende einer Therapie.

The starting dose of a drug determines both onset of action and tolerability of the compound. In contrast to most drug therapies, which may immediately be started with regular maintenance doses, compounds undergoing substantial autoinduction (e.g. carbamazepine) must be administered at slowly increasing doses to compensate for an initially low clearance and to avoid toxicity. Gradual dose escalation is also necessary whenever a drug induces substantial counter-regulatory reflex activation or adaptation processes. In these cases administration of standard doses may lead to excessive adverse reactions (e.g. cardiac decompensation after initiation of beta-receptor antagonism). Also in these situations cautious dose titration is required. After long-term administration those drugs should be withdrawn only very carefully to avoid potentially life-threatening withdrawal syndromes like hypertensive emergencies after abrupt discontinuation of clonidine or rebound epilepsies after discontinuation of anticonvulsants.

Calcium load during administration of calcium carbonate or sevelamer in individuals with normal renal function.

BACKGROUND: Under steady-state conditions urinary calcium (Ca) excretion corresponds to the Ca load in healthy subjects. However, in chronic haemodialysis patients reliable data on Ca load are not available. In these patients Ca-containing phosphate binders are suspected to play a role in the progression of arteriosclerosis via increased but not quantified Ca load. The present study evaluated the effect of calcium carbonate (CC) and sevelamer hydrochloride (SEV), a calcium-free phosphate binder, on serum Ca and urinary Ca excretion in healthy individuals. METHODS: Twelve healthy male individuals were included in a monocentre, randomized, single-blind, placebo-controlled, three-way crossover phase I study. Concurrently with their meals, participants received 4 x 2 tablets of SEV (800 mg), CC (500 mg) or placebo for 6 days with 1-week washout between the treatment periods. During the study, weekly blood samples were taken and 24-h urine was collected each day for measurement of calcium, magnesium, phosphorus, chloride and iPTH. RESULTS: Mean daily urinary phosphorus excretion was significantly lower in subjects undergoing SEV treatment compared to those taking placebo (P < 0.001). Mean daily total urinary excretion of calcium was significantly higher in CC-treated participants compared to those receiving placebo (P < 0.001). Mean 24-h calcium excretion during the 6 treatment days was 6.60 +/- 2.62 mmol [265 +/- 105 mg] (CC) versus 5.15 +/- 2.16 mmol [206 +/- 87 mg] (SEV) versus 4.95 +/- 1.63 mmol [198 +/- 65 mg] (Placebo). Taking into account nutritional calcium intake estimated from dietary records fractional calcium absorption was 8.7% (CC), 13.3% (placebo) and 14.8% (sevelamer). CONCLUSION: Intake of calcium carbonate compared to placebo in contrast to sevelamer in healthy individuals was associated with increased total urinary calcium excretion indicating an increased calcium load due to increased intestinal calcium absorption.

Quantification of cationic anti-malaria agent methylene blue in different human biological matrices using cation exchange chromatography coupled to tandem mass spectrometry.

Selective and sensitive methods for the determination of the cationic dye and anti-malarial methylene blue in human liquid whole blood, dried whole blood (paper spot), and plasma depending on protein precipitation and cation exchange chromatography coupled to electrospray ionisation (ESI) tandem mass spectrometry (MS/MS) have been developed, validated according to FDA standards, and applied to samples of healthy individuals and malaria patients within clinical studies. Acidic protein precipitation with acetonitrile and trifluoroacetic acid was used for liquid whole blood and plasma. For the extraction of methylene blue from paper spots aqueous acetonitrile was used. Sample extracts were chromatographed on a mixed mode column (cation exchange/reversed phase, Uptisphere MM1) using an aqueous ammonium acetate/acetonitrile gradient. Methylene blue was quantified with MS/MS in the selected reaction monitoring mode using ESI and methylene violet 3RAX as internal standard. Depending on the sample volume (whole blood and plasma 250 microL, and 100 microL on paper spots) the method was linear at least within 75 and 10,000 ng/mL and the limit of quantification in all matrices was 75 ng/mL. Batch-to-batch accuracies of the whole blood, plasma, and paper spot methods varied between -4.5 and +6.6%, -3.7 and +7.5%, and -5.8 and +11.1%, respectively, with corresponding precision ranging from 3.8 to 11.8% CV. After a single oral dose (500 mg) methylene blue concentrations were detectable for 72 h in plasma. The methods were applied within clinical studies to samples from healthy individuals and malaria patients from Burkina Faso.

Safety and efficacy of methylene blue combined with artesunate or amodiaquine for uncomplicated falciparum malaria: a randomized controlled trial from Burkina Faso.

BACKGROUND: Besides existing artemisinin-based combination therapies, alternative safe, effective and affordable drug combinations against falciparum malaria are needed. Methylene blue (MB) was the first synthetic antimalarial drug ever used, and recent studies have been promising with regard to its revival in malaria therapy. The objective of this study was to assess the safety and efficacy of two MB-based malaria combination therapies, MB-artesunate (AS) and MB-amodiaquine (AQ), compared to the local standard of care, AS-AQ, in Burkina Faso. METHODS AND FINDINGS: Open-label randomised controlled phase II study in 180 children aged 6-10 years with uncomplicated falciparum malaria in Nouna, north-western Burkina Faso. Follow-up was for 28 days and analysis by intention-to-treat. The treatment groups were similar in baseline characteristics and there was only one loss to follow-up. No drug-related serious adverse events and no deaths occurred. MB-containing regimens were associated with mild vomiting and dysuria. No early treatment failures were observed. Parasite clearance time differed significantly among groups and was the shortest with MB-AS. By day 14, the rates of adequate clinical and parasitological response after PCR-based correction for recrudescence were 87% for MB-AS, 100% for MB-AQ (p = 0.004), and 100% for AS-AQ (p = 0.003). By day 28, the respective figure was lowest for MB-AS (62%), intermediate for the standard treatment AS-AQ (82%; p = 0.015), and highest for MB-AQ (95%; p<0.001; p = 0.03). CONCLUSIONS: MB-AQ is a promising alternative drug combination against malaria in Africa. Moreover, MB has the potential to further accelerate the rapid parasite clearance of artemisinin-based combination therapies. More than a century after the antimalarial properties of MB had been described, its role in malaria control deserves closer attention. TRIAL REGISTRATION: ClinicalTrials.gov NCT00354380.

Cation exchange resins as pharmaceutical carriers for methylene blue: binding and release.

Methylene blue is a competitive inhibitor of the glutathione reductase of Plasmodium falciparum and is used in combination with other antimalarial drugs leading to a renaissance of methylene blue in malaria therapy. Its bitter flavour and tissue colouring property impair compliance, especially in children. These problems may be solved by binding the cationic methylene blue to cation exchange materials as pharmaceutical carriers in order to mask the undesirable properties. However, such carriers are only useful if the antimalarial is released under physiological conditions. The binding to seven cation exchange resins was studied. Ion exchangers on acrylic or methacrylic acid basis bound between 1.54 and 2.16 g methylene blue chloride trihydrate per gram ion exchanger. Polymers on divinylbenzene or styrene basis with sulphonic acid groups bound 306 and 384 mg of methylene blue chloride trihydrate per gram ion exchanger. In aqueous solution at pH of 1.5, nearly all bound methylene blue was released. The release of methylene blue from (meth)acrylic acid polymers in the presence of proteins and fat was not affected. From these data ion exchangers present a promising group of pharmaceutical carrier for the safe and compliant drug administration of methylene blue to children.

Marked differences in the prevalence of chloroquine resistance between urban and rural communities in Burkina Faso.

BACKGROUND: Chloroquine (CQ) resistance has reached high levels in Africa in recent years. Little is known about variations of resistance between urban and rural areas. OBJECTIVES: To compare the rates of in vivo resistance to CQ and the prevalences of the main molecular marker for CQ resistance among young children from urban and rural areas in Burkina Faso. METHODS: The current analysis used the frame of a randomized controlled trial (ISRCTN27290841) on the combination CQ-methylene blue (MB) (n=177) compared to CQ alone (n=45) in young children with uncomplicated malaria. We examined clinical and parasitological failure rates as well as the prevalence of the Plasmodium falciparum chloroquine resistance transporter gene (pfcrt) T76 mutation. RESULTS: Clinical and parasitological failure rates of CQ-MB differed significantly between urban (70%) and rural areas (29%, p<0.0001). Likewise, CQ failure rates were higher in the urban setting. Matching this pattern, pfcrt T76 was more frequently seen among parasite strains from urban areas (81%) when compared to rural ones (64%, p=0.01). In the presence of parasites exhibiting pfcrt T76, the odds of overall clinical failure were increased to 2.6-fold ([1.33, 5.16], p(LR)=0.005). CQ was detected at baseline in 21% and 2% of children from the urban and the rural study area, respectively (p(Chi)=0.002). CONCLUSION: Even within circumscribed geographical areas, CQ efficacy can vary dramatically. The differences in the prevalence of pfcrt T76 and in CQ failure rates are probably explained by a higher drug pressure in the urban area compared to the rural study area. This finding has important implications for national malaria policies.

Methylene blue for malaria in Africa: results from a dose-finding study in combination with chloroquine.

The development of safe, effective and affordable drug combinations against malaria in Africa is a public health priority. Methylene blue (MB) has a similar mode of action as chloroquine (CQ) and has moreover been shown to selectively inhibit the Plasmodium falciparum glutathione reductase. In 2004, an uncontrolled dose-finding study on the combination MB-CQ was performed in 435 young children with uncomplicated falciparum malaria in Burkina Faso (CQ monotherapy had a > 50% clinical failure rate in this area in 2003). Three serious adverse events (SAE) occurred of which one was probably attributable to the study medication. In the per protocol safety analysis, there were no dose specific effects. The overall clinical and parasitological failure rates by day 14 were 10% [95% CI (7.5%, 14.0%)] and 24% [95% CI (19.4%, 28.3%)], respectively. MB appears to have efficacy against malaria, but the combination of CQ-MB is clearly not effective in the treatment of malaria in Africa.

Pharmacokinetics of a netilmicin loading dose on the first postnatal day in preterm neonates with very low gestational age.

OBJECTIVE: Pharmacokinetic parameters are important for dose adjustment of aminoglycosides, but they are highly variable in neonates. In this study the pharmacokinetics of a netilmicin loading dose was investigated on the first postnatal day in preterm neonates with very low gestational age (GA). METHODS: In an open prospective study, 20 neonates with GA between 22.9 and 32.0 weeks and suspected postnatal bacterial infection received an intravenous loading dose of 5 mg/kg netilmicin over 1 h during the first postnatal day. Netilmicin serum concentrations were determined by an enzyme multiplied immunoassay. RESULTS: The systemic clearance of netilmicin normalized to body weight (BW) was not significantly different in three GA subgroups (0.59+/- 0.02 ml/min/kg for GA <24 weeks, 0.72+/-0.14 ml/min/kg for GA 24-27 weeks, and 0.62+/-0.19 ml/min/kg for GA 27-32 weeks, P=0.123). Similar results were also obtained for serum elimination half-time and for the distribution volume normalized to BW. Multiple regression analysis showed that systemic clearance and volume of distribution (both not normalized to BW) significantly correlated with BW (P<0.0001) but not with GA. In the entire group, 20% of peak concentrations were below the target of 6 mg/l, and 63% of trough concentrations were above the target of 2 mg/l. CONCLUSION: In neonates with very low GA, the pharmacokinetic parameters of netilmicin determined after an intravenous loading dose were not dependent on GA when normalized to BW. A number of neonates did not reach targeted peak and trough netilmicin serum concentrations, suggesting that a higher loading dose and a prolonged dosing interval might enhance the effectiveness and safety of netilmicin in preterm neonates immediately after birth.

[Off label use in long-term anticoagulation after liver transplantation due to phenprocoumon-induced hepatic failure]. / Off-label-Use in der Langzeit- Antikoagulation nach Lebertransplantation wegen Phenprocoumon- induzierten Leberversagens.

BACKGROUND: Drug therapy should be individualised according to criteria of efficacy, adverse effects, and treatment adherence. This is particularly important at the interface of inpatient and ambulatory care. Aspects of drug approval (labelling) and individual refunding by health care insurances should also be taken into account. CASE REPORT: A patient (male, 61, painter) showed elevated transaminases after treatment with phenprocoumon because of a deep vein thrombosis in 1999. Transaminases normalized completely after discontinuation of excluded. After a recurrent thrombosis in 2003 phenprocoumon was prescribed again followed by recurrent elevation of transaminases and subsequent cholestatic hepatitis progressing to fulminant hepatic failure that required liver transplantation. After transplantation the patient's general state of health was good and liver function nearly normal. Anticoagulation was indicated beyond the postoperative phase because of recurrent deep vein thrombosis and atrial fibrillation. A low molecular weight heparin was chosen for long-term treatment. CONCLUSION: A low molecular weight heparin appears to be the most appropriate way to maintain effective and safe anticoagulation in this patient. Coumarins carry a residual risk of an extrahepatic, immunologically mediated cross sensitization. Long-term use of ximelagatran (which has been withdrawn meanwhile) may also cause liver damage. For heparinoids, hirudines, and other drugs affecting coagulation like platelet aggregation inhibitors, therapeutic evidence is not sufficient. Though subcutaneous application of heparin is a disadvantage for the patient, therapeutic alternatives do not have better documented efficacy or less hepatotoxic potential. The low molecular weight heparin fulfils the criteria for refunding set by federal jurisdiction.