Impact of choice, timing, sequence and combination of broad-spectrum antibiotics on the outcome of allogeneic haematopoietic stem cell transplantation.

Recent data link the incidence of intestinal GvHD (iGvHD) after allogeneic haematopoietic stem cell transplantation (aSCT) to exposure with piperacillin-tazobactam or imipenem-cilastatin. To assess relevance of timing, duration, sequence and combination of antibiotic treatment in this setting, we applied a time-dependent model to our aSCT cohort. Patients from the prospective Cologne Cohort of Neutropenic Patients (CoCoNut) undergoing aSCT from January 2007 to April 2013 were included into a time-dependent multivariate Cox proportional hazards regression model with backward-stepwise selection. In 399 eligible patients, cumulative antibiotic exposure (hazard ratio (HR) 2.46; 95% confidence interval (95% CI) 1.59-3.81; P<0.001) and exposure to sequential treatment with penicillin derivatives and carbapenems (HR 6.22, 95% CI 1.27-30.31), but not to the individual classes, were associated with iGvHD at day 100. Glycopeptides were assessed as a risk factor (HR 3.73, 95% CI 1.51-9.19), but not considered independent, since their use was dependent on previous exposure to penicillin derivatives and carbapenems. Patients with iGvHD presented with increased non-relapse mortality at day 365 (HR 3.51; 95% CI 2.10-5.89; P<0.001). We identified sequential exposure to penicillin derivatives and carbapenems as well as overall exposure to antibiotics as independent risk factors for iGVHD. Confirmation of these findings in larger, prospective cohorts is necessary.

Micafungin twice weekly as antifungal prophylaxis in paediatric patients at high risk for invasive fungal disease.

BACKGROUND: Current guidelines recommend antifungal prophylaxis for children at high risk for invasive fungal disease (IFD), but the use of polyenes and triazoles may not be feasible in some patients due to toxicities and drug-drug interactions. Micafungin is well tolerated, with intravenous daily dosing being the current standard. Recent reports indicate safety and efficacy of intermittent dosing of micafungin. METHODS: We analysed safety, efficacy and micafungin serum concentrations of children at high risk for IFD receiving prophylactic micafungin between 3 and 4 mg/kg twice weekly. All children were intolerant or had contraindications to polyenes and triazoles. RESULTS: A total of 21 children (median age = 9 years) at high risk for IFD were included in the analysis. No significant clinical adverse event occurred, and end of treatment values of parameters of renal and hepatic function in serum were not different from baseline. Proven or probable breakthrough IFD did not occur in any of the patients. In 9 out of 11 patients in whom plasma micafungin concentrations were assessed, the first trough concentration exceeded 150 ng/mL, a concentration proposed to be effective for prophylaxis. CONCLUSIONS: Our data indicate that micafungin administered twice weekly at a dosage of 3-4 mg/kg of bodyweight could be a convenient, safe and efficient alternative for antifungal prophylaxis in children at high risk for IFD.

Factors influencing the pharmacokinetics of prophylactic posaconazole oral suspension in patients with acute myeloid leukemia or myelodysplastic syndrome.

OBJECTIVES: To estimate the pharmacokinetic (PK) properties of posaconazole in patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS) undergoing chemotherapy in a clinical setting. METHODS: Posaconazole concentrations in patients with AML/MDS receiving prophylactic posaconazole were determined by high-performance liquid chromatography. A population PK model with nonlinear mixed effect modeling was developed. The list of tested covariates included age, weight, height, gender, posaconazole dose, ethnicity, co-administration of antineoplastic chemotherapy, ranitidine or pantoprazole, coincident fever, diarrhea, leukocyte counts, and γ-glutamyltransterase plasma activity. RESULTS: A total of 643 serum concentrations of posaconazole from 84 patients were obtained. A one-compartment model with first order absorption and elimination as the basic structural model appropriately described the data, with an apparent clearance of 56.8 L/h [95% confidence interval (CI) 52.8­60.8 L/h] and an apparent volume of distribution of 2,130 L (95% CI 1,646­2,614 L). Significant effects on apparent clearance (CL/F) were found for presence of diarrhea and for co-medication with proton-pump inhibitors (1.5- and 1.6-fold increase in CL/F, respectively), weight (33.4 L larger apparent volume of distribution per kilogram), and co-administration of chemotherapy (0.6-fold lower apparent volume of distribution). CONCLUSION: We developed a prediction basis for mean posaconazole concentrations in AML/MDS patients. Patient weight, presence of diarrhea, and concomitant medication (chemotherapy and pantoprazole) showed significant effects on posaconazole exposure. Corresponding adjustments of the starting dose according to the presence of diarrhea and during the co-administration of chemotherapy or proton-pump inhibitors appear justified before therapeutic drug monitoring results are available. Further investigation of the interaction between different chemotherapeutic regimens and posaconazole is warranted.

Phase II dose escalation study of caspofungin for invasive Aspergillosis.

Our objective was to evaluate the maximum tolerated dose of caspofungin for invasive aspergillosis (IA). The safety and pharmacokinetics of escalating dosages of caspofungin were investigated in IA. Eight patients each received caspofungin 70, 100, 150, or 200 mg once a day (QD). Dose-limiting toxicity (DLT) was defined as the same non-hematological treatment-related adverse event of grade ≥ 4 in 2 of 8 patients or ≥ 3 in 4 of 8 patients in a cohort. A total of 46 patients (median age, 61 years; 21 female; 89% with hematological malignancies) received caspofungin (9, 8, 9, and 20 patients in the 70-, 100-, 150-, and 200-mg cohorts) for a median of 24.5 days. Plasma pharmacokinetics were linear across the investigated dosages and followed a two-compartment model, with weight as the covariate on clearance and sex as the covariate on central volume of distribution. Simulated peak plasma concentrations at steady state ranged from 14.2 to 40.6 mg/liter (28%), trough concentrations from 4.1 to 11.8 mg/liter (58%), and area under the concentration-time curve from 175 to 500 mg/liter/h (32%) (geometric mean, geometric coefficient of variation). Treatment was well tolerated without dose-limiting toxicity. The rate of complete or partial responses was 54.3%, and the overall mortality at 12-week follow-up was 28.3%. In first-line treatment of invasive aspergillosis, daily doses of up to 200 mg caspofungin were well tolerated and the maximum tolerated dose was not reached. Pharmacokinetics was linear. Response rates were similar to those previously reported for voriconazole and liposomal amphotericin.

Clinical effectiveness of posaconazole prophylaxis in patients with acute myelogenous leukaemia (AML): a 6 year experience of the Cologne AML cohort.

BACKGROUND: Large randomized controlled trials have shown significant decreases in morbidity and mortality in leukaemia patients with posaconazole prophylaxis. However, the value of prophylaxis has been questioned in centres with a low incidence of invasive fungal diseases (IFDs) and pre-emptive treatment strategies. METHODS: We prospectively evaluated the epidemiology of IFDs in acute myelogenous leukaemia (AML) patients undergoing first remission-induction chemotherapy before and after posaconazole prophylaxis had been introduced as a standard of care. Patients admitted from January 2003 to December 2005 received topical polyenes as antifungal prophylaxis (first group), while those admitted between January 2006 and December 2008 received 200 mg of oral posaconazole three times daily (second group). Other diagnostic and therapeutic standard operating procedures remained unchanged. RESULTS: A total of 82 patients in the polyene prophylaxis group and 77 in the posaconazole prophylaxis group were included in the final analysis. Baseline characteristics were well matched between groups. Patients receiving topical polyene prophylaxis were more likely to experience breakthrough IFDs (19.5% and 3.9%; P = 0.003) or breakthrough aspergillosis (13.4% and 2.6%; P = 0.018) than patients receiving systemic posaconazole prophylaxis. They also had more febrile days (mean 10.7 +/- 9.66 and 7.3 +/- 5.73; P = 0.007), longer need for inpatient treatment (mean 53.0 +/- 24.16 and 46.0 +/- 14.39; P = 0.026) and a shorter fungal-free survival (78.7 and 90.4 days; P = 0.024). No significant differences were observed for persistent fever, pneumonia, lung infiltrates indicative of invasive pulmonary aspergillosis, or attributable and overall mortality. CONCLUSIONS: After introduction of posaconazole prophylaxis for patients with AML, the number of febrile days, the incidence rate of IFDs and aspergillosis and the duration of hospitalization decreased significantly.