Mucormycosis is an emerging invasive fungal infection, primarily affecting immunocompromised patients. The disease is difficult to diagnose and mortality reaches 40% even if treated adequately. Depending on site of infection and risk factors, surgical debridement in combination with systemically active antifungal drugs are the mainstay treatment strategies. Lipid-based amphotericin B is the treatment of choice for first-line therapy while posaconazole may be a promising alternative. We performed a PubMed search on reports of patients with mucormycosis treated with posaconazole. From 2003 to 2011, 96 cases have been published. Diagnosis was based on histology alone in 2 (2.1%) and microbiological evidence in 67 (69.8%), while no data on the diagnostic approach was reported in 27 (28.1%) patients. The most frequent pathogens were Rhizopus spp. (31.2%), followed by Mucor spp. (14.6%). The site of infection was predominantly rhino-orbital (38.5%, of which 43% also had central nervous system [CNS] involvement), followed by disseminated disease (22.1%). A complete response was achieved in 62 (64.6%), partial response in 7 (7.3%) patients, and stable disease in 1 (1%). Overall mortality was 24% (lacking data for three patients). In published case reports on posaconazole treatment for mucormycosis, the drug was frequently and successfully used in combination or as second line therapy.

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.

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.

A rapid turnaround is a prerequisite of therapeutic drug monitoring (TDM). For antifungals, this need is

Our objective was to evaluate the maximum tolerated dose of caspofungin for invasive aspergillosis (IA).Invasive aspergillosis (IA) remains an important cause of infectious morbidity and mortality in immunocompromised patients. It is the most common invasive fungal disease (IFD) in patients with hematological malignancies (5). Current first-line therapies with liposomal amphotericin B and voriconazole fail in approximately 50% of patients. With 12-week mortality rates as high as 28%, new approaches are urgently needed (7, 12).High-dose liposomal amphotericin B (i.e., 10 mg/kg per day for the first 2 weeks of treatment) did not yield better outcomes than a standard dose of 3 mg/kg per day but resulted in higher rates of renal adverse events (AEs) (7). Dose escalation of voriconazole is not pursued due to the nonlinear disposition of the compound and a narrow therapeutic window. Antifungal combination therapy is another attractive strategy, but it has yet to be proven superior to monotherapy (22).Caspofungin is generally well tolerated and exhibits favorable pharmacokinetic properties (21). Unlike the triazoles, it is not metabolized through the cytochrome P450 enzyme system (11). The drug had excellent efficacy and safety results in clinical trials of candidiasis (1,17,23,24) and was effective as salvage therapy for IA after amphotericin B or itraconazole proved ineffective or toxic (15), and a large-scale study in neutropenic patients with persistent fever demonstrated an efficacy similar to that of liposomal amphotericin B but improved tolerability (26). Two recently published trials investigated the caspofungin standard maintenance doses of 50 mg once a day (QD) for first-line treatment of IA and yielded response rates of 33 and 42% (13, 25). While these response rates were below the expected outcomes (7, 12), they have been attributed to the severely ill patient groups enrolled in these trials and the rigorous enforcement of the EORTC/MSG

No abstract

Despite the availability of newer antifungal agents, invasive fungal diseases remain a leading cause of morbidity and mortality in immunocompromised patients. Voriconazole and posaconazole are two extended-spectrum triazoles indicated for treatment and prophylaxis of invasive fungal diseases. Recently, there has been increased interest in the utility of therapeutic drug monitoring to optimize safety and efficacy of antifungals in an attempt to improve patient outcomes. We reviewed the pharmacokinetic and pharmacodynamic characteristics of voriconazole and posaconazole in the context of clinical indications for therapeutic drug monitoring. In addition, the most recent evidence examining the relationship between serum concentrations of voriconazole and posaconazole and their efficacy or toxicities was evaluated. This information was then integrated to formulate recommendations for use of therapeutic drug monitoring in clinical settings.

The pharmacokinetic variability of voriconazole (VCZ) in immunocompromised children is high, and adequate exposure, particularly in the first days of therapy, is uncertain. A population pharmacokinetic model was developed to explore VCZ exposure in plasma after alternative dosing regimens. Concentration data were obtained from a pediatric phase II study. Nonlinear mixed effects modeling was used to develop the model. Monte Carlo simulations were performed to test an array of three-times-daily (TID) intravenous dosing regimens in children 2 to 12 years of age. A two-compartment model with first-order absorption, nonlinear Michaelis-Menten elimination, and allometric scaling best described the data (maximal kinetic velocity for nonlinear Michaelis-Menten clearance [] = 51.5 mg/h/70 kg, central volume of distribution [] = 228 liters/70 kg, intercompartmental clearance [] = 21.9 liters/h/70 kg, peripheral volume of distribution [] = 1,430 liters/70 kg, bioavailability [] = 59.4%, = fixed value of 1.15 mg/liter, absorption rate constant = fixed value of 1.19 h). Interindividual variabilities for ,, , and were 63.6%, 45.4%, 67%, and 1.34% on a logit scale, respectively, and residual variability was 37.8% (proportional error) and 0.0049 mg/liter (additive error). Monte Carlo simulations of a regimen of 9 mg/kg of body weight TID simulated for 24, 48, and 72 h followed by 8 mg/kg two times daily (BID) resulted in improved early target attainment relative to that with the currently recommended BID dosing regimen but no increased rate of accumulation thereafter. Pharmacokinetic modeling suggests that intravenous TID dosing at 9 mg/kg per dose for up to 3 days may result in a substantially higher percentage of children 2 to 12 years of age with adequate exposure to VCZ early during treatment. Before implementation of this regimen in patients, however, validation of exposure, safety, and tolerability in a carefully designed clinical trial would be needed.