Switching from posaconazole suspension to tablets increases serum drug levels in leukemia patients without clinically relevant hepatotoxicity

Compare the efficacy of antifungal agents as primary therapy for invasive aspergillosis: a network meta-analysis

BACKGROUND

Several antifungal agents are available for primary therapy in patients with invasive aspergillosis (IA). Although a few studies have compared the effectiveness of different antifungal agents in treating IA, there has yet to be a definitive agreement on the best choice. Herein, we perform a network meta-analysis comparing the efficacy of different antifungal agents in IA.

METHODS

We searched PubMed, Embase, and the Cochrane Central Register of Controlled Clinical Trials databases to find studies (both randomized controlled trials [RCTs] and observational) that reported on treatment outcomes with antifungal agents for patients with IA. The study quality was assessed using the revised tool for risk of bias and the Newcastle Ottawa scale, respectively. We performed a network meta-analysis (NMA) to summarize the evidence on antifungal agents' efficacy (favourable response and mortality).

RESULTS

We found 12 studies (2428 patients) investigating 11 antifungal agents in the primary therapy of IA. There were 5 RCTs and 7 observational studies. When treated with monotherapy, isavuconazole was associated with the best probability of favourable response (SUCRA, 77.9%; mean rank, 3.2) and the best reduction mortality against IA (SUCRA, 69.1%; mean rank, 4.1), followed by voriconazole and posaconazole. When treated with combination therapy, Liposomal amphotericin B plus caspofungin was the therapy associated with the best probability of favourable response (SUCRA, 84.1%; mean rank, 2.6) and the best reduction mortality (SUCRA, 88.2%; mean rank, 2.2) against IA.

CONCLUSION

These findings suggest that isavuconazole, voriconazole, and posaconazole may be the best antifungal agents as the primary therapy for IA. Liposomal amphotericin B plus caspofungin could be an alternative option.

Utility of triazole antifungal therapeutic drug monitoring: Insights from the Society of Infectious Diseases Pharmacists: Endorsed by the Mycoses Study Group Education and Research Consortium

Triazole antifungals (i.e., fluconazole, itraconazole, voriconazole, posaconazole, and isavuconazole) are commonly used in clinical practice to prevent or treat invasive fungal infections. Most triazole antifungals require therapeutic drug monitoring (TDM) due to highly variable pharmacokinetics, known drug interactions, and established relationships between exposure and response. On behalf of the Society of Infectious Diseases Pharmacists (SIDP), this insight describes the pharmacokinetic principles and pharmacodynamic targets of commonly used triazole antifungals and provides the rationale for utility of TDM within each agent.

Hepatic safety of the antifungal triazole agent posaconazole: characterization of adverse event reports in a manufacturer's safety database

BACKGROUND

Second-generation triazoles including posaconazole are efficacious for prophylaxis and salvage treatment of life-threatening invasive fungal diseases but have been associated with hepatic adverse events (AEs). This report evaluated hepatic AEs in posaconazole-treated patients.

RESEARCH DESIGN AND METHODS

Hepatobiliary AEs with posaconazole exposure in the company's global safety database were analyzed to characterize underlying medical conditions and concomitant drug exposure.

RESULTS

As of October 2019, 516 cases (168 from clinical trials, 348 from postmarketing use) containing 618 hepatobiliary AEs were reported regardless of causality. Frequently reported terms were hyperbilirubinemia, hepatic failure, and hepatic function abnormal (clinical trials reports) and hepatotoxicity, hepatocellular injury, and hepatic function abnormal (postmarketing reports). Cases reporting concurrent medications associated with drug-induced liver injury (DILI) included 8% with verified severe DILI (vMost-DILI) concern, 24% with verified mild to moderate DILI (vLess-DILI) concern, and 37% received both vMost-DILI and vLess-DILI-concern medications in the DILIrank data set.

CONCLUSIONS

Use of concomitant medications with known risks for hepatic injury appears to be an important contributor for the development of hepatotoxicity in patients treated with posaconazole.

Evaluating posaconazole, its pharmacology, efficacy and safety for the prophylaxis and treatment of fungal infections

INTRODUCTION

Invasive fungal diseases (IFDs) are a significant cause of morbidity and mortality among immunocompromised patients. Safe and effective antifungal medications used for prophylaxis and treatment are pivotal in their management. Posaconazole is a promising triazole antifungal agent.

AREAS COVERED

The authors discuss the pharmacological properties of posaconazole, including pharmacokinetics/pharmacodynamics, safety and tolerability profile, together with efficacy data for prophylaxis and treatment as well as its use in special populations based on current literature.

EXPERT OPINION

Posaconazole has a favorable safety and tolerability profile; however, caution is advised when co-administered with agents that are CYP3A4 inhibitors, because their concentration may significantly increase, and their levels should be closely monitored. It has an extended spectrum of activity against yeasts and filamentous fungi. It is successfully used as prophylaxis for patients with acute myeloid leukemia (AML)/myelodysplastic syndrome (MDS) and post-hematopoietic cell transplantation (HCT) with graft-versus-host disease (GVHD). It is the first line treatment for oropharyngeal candidiasis and is also used as a salvage treatment for refractory IFDs. Currently available formulations include the oral suspension, delayed-release tablets and solution for intravenous infusion, all with different PK/PD properties and indications. Its use in children and adolescents is currently being examined in Phase-II clinical trials.

Potency and preclinical evidence of synergy of oral azole drugs and miltefosine in an ex vivo model of Leishmania (Viannia) panamensis infection

Failure of treatment of cutaneous leishmaniasis with antimonial drugs and miltefosine is frequent. Use of oral combination therapy represents an attractive strategy to increase efficacy of treatment and reduce the risk of drug resistance. We evaluated the potency of posaconazole, itraconazole, voriconazole and fluconazole, and the potential synergy of those demonstrating the highest potency, in combination with miltefosine (HePC), against infection with Leishmania (Viannia) panamensis. Synergistic activity was determined by isobolograms and calculation of Fractional Inhibitory Concentration Index (FICI), based on parasite quantification using an ex vivo model of human PBMCs infected with a luciferase-transfected, antimony and miltefosine sensitive line of L. panamensis. The drug combination and concentrations that displayed synergy were then evaluated for anti-leishmanial effect in 10 clinical strains of L. panamensis by qRT-PCR of Leishmania 7SLRNA. High potency was substantiated for posaconazole and itraconazole against sensitive as well as HePC and antimony resistant lines of L. panamensis, whereas fluconazole and voriconazole displayed low potency. HePC combined with posaconazole (Poz) demonstrated evidence of synergy at free drug concentrations achieved in plasma during treatment (2 μM HePC + 4 μM Poz). FICI, based on 70% and 90% reduction of infection, was 0.5 for the sensitive line. Combination of 2 μM HePC + 4 μM Poz effected significantly greater reduction of infection by clinical strains of L. panamensis than individual drugs. Orally administrable miltefosine/posaconazole combinations demonstrated synergistic anti-leishmanial capacity ex vivo against L. panamensis, supporting their potential as a novel therapeutic strategy to improve efficacy, and effectiveness of treatment.

Management of posaconazole-induced pseudohyperaldosteronism

BACKGROUND

Posaconazole-induced pseudohyperaldosteronism (PIPH) has been associated with elevated posaconazole serum concentrations. Clinicians are faced with the difficult task of managing patients with PIPH while maintaining the efficacy of antifungal therapy. Commonly, modifications to posaconazole therapy are utilized in managing PIPH, including dosage reduction of posaconazole or switch to an alternative antifungal.

OBJECTIVES

To characterize the management of patients diagnosed with PIPH and their response to various therapeutic interventions.

METHODS

We retrospectively reviewed 20 consecutive adult patients diagnosed with PIPH. Patient data collected included blood pressure, electrolytes, endocrine laboratory values and posaconazole serum concentrations collected before and after therapeutic intervention.

RESULTS

Of 20 patients included, 17 patients (85%) underwent therapeutic modification, with posaconazole dose reduction (n = 11) as the most common change. Other modifications included discontinuation (n = 3), switch to an alternative antifungal (n = 2) and addition of spironolactone (n = 1). Clinical improvement (decrease in systolic blood pressure and increase in serum potassium) was observed in 9 of 17 patients (52.9%). An average decrease in systolic blood pressure of 7.1 mmHg and increase in serum potassium of 0.22 mmol/L was observed following therapeutic modification.

CONCLUSIONS

We report our experience with PIPH management, for which there is no universally effective strategy. We utilized a stepwise approach for management, starting with posaconazole dose reduction and repeat assessment of clinical and laboratory parameters. If resolution of PIPH is not achieved, an alternative triazole antifungal or the addition of an aldosterone antagonist are additional potential interventions. It is possible for PIPH to persist after therapeutic modification despite these interventions. Thus, early diagnosis and continuous monitoring is warranted.

Aspergillosis: Epidemiology, Diagnosis, and Treatment

The spectrum of disease produced by Aspergillus species ranges from allergic syndromes to chronic pulmonary conditions and invasive infections. Invasive aspergillosis is a major cause of morbidity and mortality in immunocompromised patients. Risk factors continue to evolve and include newer biological agents that target the immune system and postinfluenza infection; and it has been observed following COVID-19 infection. Diagnosis remains a challenge but non-culture-based methods are available. Antifungal resistance has emerged. Voriconazole remains the treatment of choice but isavuconazole and posaconazole have similar efficacy with less toxicity. Combination therapy is used with extensive infection and in severe immunosuppression.

Comparison of invasive fungal diseases between patients with acute myeloid leukemia receiving posaconazole prophylaxis and those not receiving prophylaxis: A single-center, observational, case-control study in South Korea

Posaconazole prophylaxis is effective in decreasing the incidence of invasive fungal diseases (IFDs) in patients with acute myeloid leukemia (AML). However, the use of antifungal prophylaxis varies in real-life practice, and only a small number of studies have compared the incidence of IFDs between those receiving posaconazole prophylaxis and those without prophylaxis. We compared the clinical characteristics and outcomes of IFDs between patients with AML who received posaconazole prophylaxis and those without antifungal prophylaxis.We reviewed the medical records of adult AML patients who underwent induction chemotherapy between June 2016 and October 2019 at Asan Medical Center (Seoul, South Korea), where posaconazole prophylaxis is not administered in patients with gastrointestinal symptoms that may hinder sufficient absorption of oral prophylactic agents, and in patients with abnormal liver functions considering the possible exacerbation of adverse events. Patients who received posaconazole prophylaxis for ≥7 days were included in the prophylaxis group. Clinical characteristics and outcomes including the incidence of IFDs were compared between the 2 groups.Of the 247 patients with AML who underwent induction chemotherapy, 162 (66%) received posaconazole prophylaxis and 85 (34%) did not receive any prophylaxis. The incidence of proven/probable IFD was significantly higher in the no prophylaxis group than in the prophylaxis group (9.4% [8/85] vs 2.5% [4/162], P = .03). Of the 8 cases of IFDs in the no prophylaxis group, 7 were mold infections and 1 was invasive candidiasis. Of the 4 cases of IFDs in the prophylaxis group, 3 were mold infections and 1 was invasive candidiasis. Patients with posaconazole prophylaxis less frequently received therapeutic antifungal therapy (2.5% vs 9.4%, P = .03) and had a longer median, duration from chemotherapy to antifungal therapy compared with the no prophylaxis group (18 vs 11 days, P < .01). The rate of IFD-related mortality was similar between the 2 groups (0.6% vs 0%, P > .99).Patients with AML who received posaconazole prophylaxis had a lower incidence of breakthrough IFDs compared with those who did not receive any prophylaxis. Invasive mold infection was the most common IFD regardless of antifungal prophylaxis.

Leveraging Oral Drug Development to a Next Level: Impact of the IMI-Funded OrBiTo Project on Patient Healthcare

A thorough understanding of the behavior of drug formulations in the human gastrointestinal (GI) tract is essential when working in the field of oral drug development in a pharmaceutical company. For orally administered drug products, various GI processes, including disintegration of the drug formulation, drugrelease, dissolution, precipitation, degradation, dosage form transit and permeation, dictate absorption into the systemic circulation. These processes are not always fully captured in predictive in vitro and in silico tools, as commonly applied in the pre-clinical stage of formulation drug development. A collaborative initiative focused on the science of oral biopharmaceutics was established in 2012 between academic institutions and industrial companies to innovate, optimize and validate these in vitro and in silico biopharmaceutical tools. From that perspective, the predictive power of these models can be revised and, if necessary, optimized to improve the accuracy toward predictions of the in vivo performance of orally administered drug products in patients. The IMI/EFPIA-funded "Oral Bioavailability Tools (OrBiTo)" project aimed to improve our fundamental understanding of the GI absorption process. The gathered information was integrated into the development of new (or already existing) laboratory tests and computer-based methods in order to deliver more accurate predictions of drug product behavior in a real-life setting. These methods were validated with the use of industrial data. Crucially, the ultimate goal of the project was to set up a scientific framework (i.e., decision trees) to guide the use of these new tools in drug development. The project aimed to facilitate and accelerate the formulation development process and to significantly reduce the need for animal experiments in this area as well as for human clinical studies in the future. With respect to the positive outcome for patients, high-quality oral medicines will be developed where the required dose is well-calculated and consistently provides an optimal clinical effect. In a first step, this manuscript summarizes the setup of the project and how data were collected across the different work packages. In a second step, case studies of how this project contributed to improved knowledge of oral drug delivery which can be used to develop improved products for patients will be illustrated.

American Society of Transplantation and Cellular Therapy Series, 2: Management and Prevention of Aspergillosis in Hematopoietic Cell Transplantation Recipients

The Practice Guidelines Committee of the American Society of Transplantation and Cellular Therapy partnered with its Transplant Infectious Disease Special Interest Group to update its 2009 compendium-style infectious disease guidelines for hematopoietic cell transplantation (HCT). A completely fresh approach was taken with the goal of better serving clinical providers by publishing each standalone topic in the infectious disease series as a concise format of frequently asked questions (FAQs), tables, and figures. Adult and pediatric infectious disease and HCT content experts developed, then answered FAQs, and finalized topics with harmonized recommendations that were made by assigning an A through E strength of recommendation paired with a level of supporting evidence graded I through III. This second guideline in the series focuses on invasive aspergillosis, a potentially life-threatening infection in the peri-HCT period. The relevant risk factors, diagnostic considerations, and prophylaxis and treatment approaches are reviewed.

Posaconazole Serum Drug Levels Associated With Pseudohyperaldosteronism

BACKGROUND

Posaconazole tablets are well tolerated and efficacious in the prophylaxis and treatment of aspergillosis, mucormycosis, and other invasive fungal infections. There have been case reports of posaconazole-induced pseudohyperaldosteronism (PIPH); however, its occurrence and association with serum posaconazole drug levels have not previously been investigated.

METHODS

In this single-center, retrospective, observational study, we examined the occurrence of PIPH in outpatients newly starting posaconazole and evaluated differences in serum posaconazole concentrations and clinical characteristics between those with and without this syndrome.

RESULTS

Sixty-nine patients receiving posaconazole were included, of whom 16 (23.2%) met the definition of PIPH. Patients with PIPH were significantly older (61.1 vs 44.7 years, P = .007) and more frequently had hypertension prior to starting posaconazole (68.8% vs 32.1%, P = .009). Patients with PIPH had a significantly higher median serum posaconazole level than those without PIPH (3.0 vs 1.2 µg/mL, P ≤ .0001). There was a positive correlation between serum posaconazole levels and changes in systolic blood pressure (r = .37, P = .01), a negative correlation between serum posaconazole levels and changes in serum potassium (r = -.39, P = .006), and a positive correlation between serum posaconazole levels and serum 11-deoxycortisol (r = .69, P < .0001).

CONCLUSIONS

Posaconazole is associated with secondary hypertension and hypokalemia, consistent with pseudohyperaldosteronism, and development is associated with higher serum posaconazole concentrations, older age, and baseline hypertension.

Pharmacokinetics and Pharmacodynamics of Posaconazole

Posaconazole is typically used for preventing invasive yeast and mold infections such as invasive aspergillosis in high-risk immunocompromised patients. The oral suspension was the first released formulation and many pharmacokinetic and pharmacodynamic studies of this formulation have been published. Erratic absorption profiles associated with this formulation were widely reported. Posaconazole exposure was found to be significantly influenced by food and many gastrointestinal conditions, including pH and motility. As a result, low posaconazole plasma concentrations were obtained in large groups of patients. These issues of erratic absorption urged the development of the subsequently marketed delayed-release tablet, which proved to be associated with higher and more stable exposure profiles. Shortly thereafter, an intravenous formulation was released for patients who are not able to take oral formulations. Both new formulations require a loading dose on day 1 to achieve high posaconazole concentrations more quickly, which was not possible with the oral suspension. So far, there appears to be no evidence of increased toxicity correlated to the higher posaconazole exposure achieved with the regimen for these formulations. The higher systemic availability of posaconazole for the delayed-release tablet and intravenous formulation have resulted in these two formulations being preferable for both prophylaxis and treatment of invasive fungal disease. This review aimed to integrate the current knowledge on posaconazole pharmacokinetics, pharmacodynamics, major toxicity, existing resistance, clinical experience in special populations, and new therapeutic strategies in order to get a clear understanding of the clinical use of this drug.

Gynecomastia and hypertension in a patient treated with posaconazole

Posaconazole therapy may lead to increased serum estradiol levels and development of gynecomastia. Early detection by endocrine hormone measurements may help preventing gynecomastia.

Therapeutic drug monitoring and adverse events of delayed-release posaconazole tablets in patients with chronic pulmonary aspergillosis

BACKGROUND

Posaconazole delayed-release tablets offer better bioavailability than the liquid suspension, but no post-marketing data are available in immunocompetent hosts such as those with chronic pulmonary aspergillosis (CPA).

OBJECTIVES

To explore the pharmacokinetics and adverse event (AE) profile of posaconazole tablets in patients with CPA.

METHODS

Patients started on posaconazole tablets at the National Aspergillosis Centre (NAC), Manchester, UK between February 2014 and October 2015 were identified from the NAC database and analysed retrospectively. The medical records were reviewed for factors that could affect posaconazole serum levels and the development of AEs.

RESULTS

Seventy-two patients were included; 50 (69%) were male and the mean age was 48.5 ± 12 years. Therapeutic levels (≥1 mg/L) were achieved in 90% of cases on 200 mg versus 90% of cases on 300 mg daily (P = not significant). Based on multivariate analysis, female sex (P = 0.041), a 100 mg daily dose (P < 0.001), asthma (P = 0.01) and bronchiectasis (P = 0.001) were associated with subtherapeutic levels. Forty-nine (68%) patients developed AEs, mainly fatigue (37%), dyspnoea (18%) and nausea (12%). AEs were present on 115/196 (59%) occasions on 300 mg/day and on 45/115 (39%) occasions on 200 mg/day (P < 0.01). The mean level was 1.81 ± 0.96 mg/L for patients reporting no AEs and 1.90 ± 1.11 mg/L for those reporting AEs (P = not significant). Factors associated with AEs of grade ≥2 were a daily dose of 300 versus 200 mg (P = 0.001) and asthma (P = 0.008).

CONCLUSIONS

A lower-than-recommended posaconazole tablet dose achieved therapeutic levels in most patients and was better tolerated. Males were more likely to achieve a therapeutic level. Underlying conditions affected the degree and frequency of AEs.

Tablets or oral suspension for posaconazole in lung transplant recipients? Consequences for trough concentrations of tacrolimus and everolimus

AIMS

A new formulation of posaconazole (PCZ), delayed-release tablets (PCZ-tab), increases PCZ bioavailability and plasma trough concentrations (C_min ) over those achieved with an oral suspension (PCZ-susp). PCZ is an inhibitor of cytochrome P450 3A4 and P-glycoprotein. We therefore investigated the impact of PCZ-tab treatment on blood C_min and doses of tacrolimus (TAC) and everolimus (EVR).

METHODS

Eighteen lung transplant patients receiving TAC (n = 13) or TAC + EVR (n = 5) between June 2015 and March 2016 were retrospectively included. Ten of these patients received both PCZ-tab and PCZ-susp (i.e. switched patients); the other 8 received only PCZ-tab. Plasma C_min of PCZ (n = 64), blood C_min of TAC (n = 299) and EVR (n = 80) were determined during routine therapeutic drug monitoring by liquid chromatography-tandem mass spectrometry.

RESULTS

PCZ C_min on PCZ-tab treatment (n = 48) was 2.5 times higher than that on PCZ-susp therapy (n = 16), for both PCZ patients (P < .0001) and for switched patients (P = .003). PCZ initiation, regardless of galenic form, increased TAC and EVR C_min adjusted for dose (D), 3-fold and 3.5-fold, respectively (P < .0001 for both). PCZ-tab treatment was associated with a higher TAC C_min /D (PCZ-tab vs PCZ-susp: 0.004 ± 0.004 L^-1 vs 0.009 ± 0.006 L^-1 , P < .0001) and lower TAC daily dose than PCZ-susp (PCZ-tab vs PCZ-susp: 1.08 ± 0.92 vs 2.32 ± 1.62 mg d^-1 , P < .0001). EVR C_min /D was higher and EVR dose tended to be lower on PCZ-tab than on PCZ-susp.

CONCLUSION

The greater PCZ exposure achieved during PCZ-tab treatment increased drug-drug interactions with TAC and EVR, resulting in greater exposure, potentially exposing patients to higher risks of adverse effects.

Pharmacokinetics and Safety of Posaconazole Tablet Formulation in Chinese Participants at High Risk for Invasive Fungal Infection

INTRODUCTION

This study characterized the multidose pharmacokinetic (PK) characteristics of posaconazole tablets used as prophylactic antifungal therapy in Chinese patients with acute myelogenous leukemia (AML) at risk for invasive fungal infection (IFI).

METHODS

Participants in this open-label, single-arm, phase 1b study received posaconazole 300 mg twice daily on day 1 and then once daily for up to 28 days. In the intensive PK sampling subgroup, posaconazole was administered under fasting conditions on days 1 and 8, and blood samples were regularly collected over 24 h. Trough PK sampling was conducted in all participants on days 1, 2, 3, 8, 14, 21, and 28 without regard for food intake. Population PK characteristics were predicted using PK modeling. Primary endpoints were steady-state average concentration (C_avg) and percentage of participants with steady-state C_avg (predicted and observed) > 500 ng/ml. Treatment safety and efficacy were secondary endpoints.

RESULTS

Sixty-five adult Chinese participants were enrolled. On day 8, steady-state arithmetic mean C_avg was 1610 ng/ml (% coefficient of variation [%CV] 42.8%) in the intensive PK subgroup (n = 20). All participants achieved a steady-state C_avg > 500 ng/ml. Predicted C_avg (pC_avg) was 1770 ng/ml (%CV 33.7%) in the total population (n = 64); 92.2% of participants had pC_avg values ≥ 500 ng/ml (n = 59). The posaconazole tablet safety profile was consistent with that of the oral formulation, and the IFI rate was 3%.

CONCLUSION

In Chinese AML patients, the posaconazole 300-mg tablet provided PK data comparable with those of previous studies and was generally well tolerated and efficacious.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT02387983.

Make Sure You Have a Safety Net: Updates in the Prevention and Management of Infectious Complications in Stem Cell Transplant Recipients

Hematopoietic stem cell transplant recipients are at increased risk of infection and immune dysregulation due to reception of cytotoxic chemotherapy; development of graft versus host disease, which necessitates treatment with immunosuppressive medications; and placement of invasive catheters. The prevention and management of infections in these vulnerable hosts is of utmost importance and a key “safety net” in stem cell transplantation. In this review, we provide updates on the prevention and management of CMV infection; invasive fungal infections; bacterial infections; Clostridium difficile infection; and EBV, HHV-6, adenovirus and BK infections. We discuss novel drugs, such as letermovir, isavuconazole, meropenem-vaborbactam and bezlotoxumab; weigh the pros and cons of using fluoroquinolone prophylaxis during neutropenia after stem cell transplantation; and provide updates on important viral infections after hematopoietic stem cell transplant (HSCT). Optimizing the prevention and management of infectious diseases by using the best available evidence will contribute to better outcomes for stem cell transplant recipients, and provide the best possible “safety net” for these immunocompromised hosts.

Therapeutic Drug Monitoring of Antifungal Drugs: Another Tool to Improve Patient Outcome?

Introduction

This study aimed to examine the relationship among adequate dose, serum concentration and clinical outcome in a non-selected group of hospitalized patients receiving antifungals.

Methods

Prospective cross-sectional study performed between March 2015 and June 2015. Dosage of antifungals was considered adequate according to the IDSA guidelines, whereas trough serum concentrations (determined with HPLC) were considered adequate as follows: fluconazole > 11 µg/ml, echinocandins > 1 µg/ml, voriconazole 1–5.5 µg/ml and posaconazole > 0.7 µg/ml.

Results

During the study period, 84 patients (65.4% male, 59.6 years) received antifungals for prophylaxis (40.4%), targeted (31.0%) and empirical therapy (28.6%). The most frequent drug was micafungin (28/84; 33.3%) followed by fluconazole (23/84; 27.4%), voriconazole (15/84; 17.9%), anidulafungin (8/84; 9.5%), posaconazole (7/84; 8.3%) and caspofungin (3/84; 3.6%). Considerable interindividual variability was observed for all antifungals with a large proportion of the patients (64.3%) not attaining adequate trough serum concentrations, despite receiving an adequate antifungal dose. Attaining the on-target serum antifungal level was significantly associated with a favorable clinical outcome (OR = 0.02; 95% CI 0.01–0.64; p = 0.03), whereas the administration of an adequate antifungal dosage was not.

Conclusions

With the standard antifungal dosage, a considerable proportion of patients have low drug concentrations, which are associated with poor clinical outcome.

Therapeutic drug monitoring of systemic antifungal agents: a pragmatic approach for adult and pediatric patients

Introduction: Therapeutic drug monitoring (TDM) has been shown to optimize the management of invasive fungal infections (IFIs), particularly for select antifungal agents with a well-defined exposure-response relationship and an unpredictable pharmacokinetic profile or a narrow therapeutic index. Select triazoles (itraconazole, voriconazole, and posaconazole) and flucytosine fulfill these criteria, while the echinocandins, fluconazole, isavuconazole, and amphotericin B generally do not do so. Given the morbidity and mortality associated with IFIs and the challenges surrounding the use of currently available antifungal agents, TDM plays an important role in therapy.Areas covered: This review seeks to describe the rationale for TDM of antifungal agents, summarize their pharmacokinetic and pharmacodynamic properties, identify treatment goals for efficacy and safety, and provide recommendations for optimal dosing and therapeutic monitoring strategies.Expert opinion: Several new antifungal agents are currently in development, including compounds from existing antifungal classes with enhanced pharmacokinetic or safety profiles as well as agents with novel targets for the treatment of IFIs. Given the predictable pharmacokinetics of these newly developed agents, use of routine TDM is not anticipated. However, expanded knowledge of exposure-response relationships of these compounds may yield a role for TDM to improve outcomes for adult and pediatric patients.

Treatment by Posaconazole Tablets, Compared to Posaconazole Suspension, Does Not Reduce Variability of Posaconazole Trough Concentrations

The delayed-release tablet formulation of posaconazole (POS-tab) results in higher plasma POS trough concentrations (C_min) than the oral suspension (POS-susp), which raises the question of the utility of therapeutic drug monitoring (TDM). We aimed to compare the variability of the POS C_min for the two formulations and identify determinants of the POS-tab C_min and its variability. Demographic, biological, and clinical data from 77 allogeneic hematopoietic stem cell transplant patients (874 C_min) treated with POS-tab (n = 41), POS-susp (n = 29), or both (n = 7) from January 2015 to December 2016 were collected retrospectively. Interpatient and within-subject coefficients of variation (CVs) of the C_min adjusted to dose (D) were calculated for each formulation. Between-group comparisons were performed using a linear mixed effects model. The POS C_min was higher for the tablet than for the suspension (median [25th-75th percentile]: 1.8 [1.2-2.4] mg/liter versus 1.2 [0.7-1.6] mg/liter, P < 0.0001). Interpatient CVs for the tablet and suspension were 60.8 versus 63.5% (P = 0.7), whereas within-subject CVs were 39.7 and 44.9%, respectively (P = 0.3). Univariate analysis showed that age and treatment by POS-tab were significantly and positively associated with the POS C_min, whereas diarrhea was associated with a diminished POS C_min Multivariate analysis identified treatment with POS-tab and diarrhea as independent factors of the POS C_min, with a trend toward a lower impact of diarrhea during treatment with POS-tab (P = 0.07). Despite increased POS exposure with the tablet formulation, the variability of the POS C_min was not significantly lower than that of the suspension. This suggests that TDM may still be useful to optimize tablet POS therapy.

Using State Transition Models to Explore How the Prevalence of Subtherapeutic Posaconazole Exposures Impacts the Clinical Utility of Therapeutic Drug Monitoring for Posaconazole Tablets and Oral Suspension

Therapeutic drug monitoring (TDM) has been recommended in guidelines for patients receiving posaconazole oral suspension, but its utility in patients receiving posaconazole tablet, which has an improved bioavailability, remains unclear. We used state transition models with first-order Monte Carlo microsimulation to re-examine the posaconazole exposure-response relationships reported in two Phase III clinical trials (prophylaxis with posaconazole oral suspension - Models 1 & 2) and a third multicenter observational TDM study (Model 3). We simulated the impact of TDM-guided interventions to improve initial average posaconazole concentrations (C_avg) to reduce clinical failure (in Models 1 & 2) and breakthrough invasive fungal disease (bIFD) in Model 3. Simulations were then repeated using posaconazole tablet C_avg distributions in place of the oral suspension formulation. In all three models with posaconazole oral suspension, TDM interventions associated with maximal improvement in posaconazole C_avg reduced absolute rates of subtherapeutic exposures (C_avg < 700 ng/mL) by 25-49%. Predicted reductions in absolute clinical failure rates were 11% in Model 1 and 6.5% in Model 2, and a 12.6% reduction in bIFD in Model 3. With the tablet formulation, maximally-effective TDM interventions reduced subtherapeutic exposures by approximately 5% in all three models and absolute clinical failure rates by 3.9% in Model 1, and 1.6% in Model 2; and a 1.6% reduction in bIFD in Model 3. Our modeling suggests that routine TDM during prophylaxis with posaconazole tablets may have limited clinical utility unless populations with higher prevalence (>10%) of subtherapeutic exposures can be identified based on clinical risk factors.

Refining the therapeutic range of posaconazole and isavuconazole for efficient therapeutic drug monitoring using a bioassay approach

Therapeutic drug monitoring (TDM) of antifungal triazole was recommended, except for isavuconazole (ISA) whose target trough concentrations (C_min ) need to be specified. Concerning posaconazole (POS), tablet formulation results in higher exposure but no upper C_min threshold has been yet proposed. We aimed to investigate the pharmacokinetic-pharmacodynamic relationship of POS and ISA, using a bioassay approach as surrogate marker of antifungal activity, in order to refine the therapeutic C_min of both antifungals. A bioassay using a cellulose disk diffusion method was performed to determine the growth inhibition zone (GIZ) of POS and ISA on Aspergillus fumigatus and Candida parapsilosis (ISA only). GIZs of plasma from patients undergoing TDM for POS (n = 136) or ISA (n = 40) were determined. GIZs of plasma patients and antifungal C_min were highly correlated for ISA (A. fumigatus: ρ = 0.942, P < 0.0001; C. parapsilosis: ρ = 0.949, P < 0.0001) and POS (ρ = 0.922, P < 0.0001), and these relationships were represented with a Michaelis-Menten model. Based on this modeling, the recommended thresholds of 0.7, 1, and 1.25 mg/L for the POS C_min corresponded to 50.1, 55.2, and 59.1% of the maximal GIZ, respectively. We propose an upper threshold of 4.8 mg/L for the POS C_min and a lower threshold of 2.0 mg/L for the C_min of ISA, as they respectively corresponded to concentrations leading to 90% and 50% of the maximal GIZ on A. fumigatus. The determination of antifungal activity using this bioassay allowed refining target C_min of POS and ISA, especially the upper threshold of POS (4.8 mg/L) and the lower threshold of ISA (2.0 mg/L).

Single-centre study of therapeutic drug monitoring of posaconazole in lung transplant recipients: factors affecting trough plasma concentrations

Objectives

This study describes therapeutic drug monitoring (TDM) of posaconazole suspension and modified release (MR) tablets in lung transplant (LTx) recipients and evaluates factors that may affect posaconazole trough plasma concentration (Cmin).

Methods

A single-centre, retrospective study evaluating posaconazole Cmin in LTx recipients receiving posaconazole suspension or MR tablets between January 2014 and December 2016.

Results

Forty-seven LTx patients received posaconazole suspension, and 78 received the MR tablet formulation; a total of 421 and 617 Cmin measurements were made, respectively. Posaconazole was concurrently administered with proton pump inhibitor in ≥ 90% of patients. The median (IQR) of initial posaconazole Cmin following 300 mg daily of posaconazole tablet was significantly higher than that of 800 mg daily of posaconazole suspension [1.65 (0.97-2.13) mg/L versus 0.81 (0.48-1.15) mg/L, P < 0.01]. Variability in posaconazole Cmin was apparent regardless of the formulations prescribed and dose adjustments were routinely undertaken to maintain therapeutic Cmin. A clear dose-response relationship was observed in patients receiving posaconazole MR tablets. Non-specific adverse events (fatigue, tremor, lethargy, sweating, nausea/vomiting and weight loss) were reported in 3/78 (4%) patients receiving posaconazole MR tablets. Posaconazole Cmin in these three patients was determined to be 9.6, 6.2 and 2.3 mg/L.

Conclusions

The current study has provided clinically important insights into the TDM of posaconazole in LTx recipients. Routine TDM should be undertaken in LTx recipients receiving posaconazole suspension and/or MR tablets.

Posaconazole salvage therapy: The Posifi study

BACKGROUND

Posaconazole (PCZ) is used mainly for the prevention of invasive fungal infection (IFI).

METHODS

A multicentre retrospective, investigational study using a non-randomized, single-arm design carried out in six tertiary hospitals in Spain to evaluate the use of PCZ in different forms of administration in the (non-prophylactic) treatment of IFI.

RESULTS

Over an eight-year-period, 67 patients were included in this study. PCZ was administered as salvage therapy (intolerant or refractory to a previous antifungal agent) in 65/67 (97%); of these, it was used against Aspergillosis (68.6%), Zygomycosis (13.4%), other moulds (8.9%) and yeast (10.5%). The median duration of PCZ therapy was 75 days. The oral solution was associated with low serum levels (<0.7 mg/L) in 63% of available patients. Clinical response at 3 and 12 months of PCZ therapy were for aspergillosis: 47.8% and 41.3%; for zygomycosis: 55.5% and 55.5%; and for other mycoses: 69.2% and 69.2%, respectively. Suspension by toxicity was only observed in 6% and 7.5% of patients at 3 and 12 months, respectively, mainly with grade III/IV elevations of liver function test (LFTs).

CONCLUSIONS

Posaconazole salvage therapy, especially oral tablets, can be an effective alternative option for patients with IFI who cannot tolerate or do not respond to other antifungal therapies.

Treatment of Posaconazole-Induced Peripheral Neuropathy With Methylprednisolone and Magnesium Infusions: A Case Report

The tolerability of long-term posaconazole use remains poorly defined. We present a patient who developed peripheral neuropathy following long-term exposure to the tablet formulation of posaconazole, which was treated with methylprednisolone and magnesium infusions. The potential role of methylprednisolone and magnesium infusions in managing this potentially irreversible triazole-associated complication requires further study.

Examination of Fluconazole-Induced Alopecia in an Animal Model and Human Cohort

Fluconazole-induced alopecia is a significant problem for patients receiving long-term therapy. We evaluated the hair cycle changes of fluconazole in a rat model and investigated potential molecular mechanisms. Plasma and tissue levels of retinoic acid were not found to be causal. Human patients with alopecia attributed to fluconazole also underwent detailed assessment and in both our murine model and human cohort fluconazole induced telogen effluvium. Future work further examining the mechanism of fluconazole-induced alopecia should be undertaken.

Breakthrough Invasive Mold Infections in the Hematology Patient: Current Concepts and Future Directions

Although the widespread use of mold-active agents (especially the new generation of triazoles) has resulted in reductions of documented invasive mold infections (IMIs) in patients with hematological malignancies and allogeneic hematopoietic stem cell transplantation (HSCT), a subset of such patients still develop breakthrough IMIs (bIMIs). There are no data from prospective randomized clinical trials to guide therapeutic decisions in the different scenarios of bIMIs. In this viewpoint, we present the current status of our understanding of the clinical, diagnostic, and treatment challenges of bIMIs in high-risk adult patients with hematological cancer and/or HSCT receiving mold-active antifungals and outline common clinical scenarios. As a rule, managing bIMIs demands an individualized treatment plan that takes into account the host, including comorbidities, certainty of diagnosis and site of bIMIs, local epidemiology, considerations for fungal resistance, and antifungal pharmacological properties. Finally, we highlight areas that require future investigation in this complex area of clinical mycology.

Clinical Outcomes of Oral Suspension versus Delayed-Release Tablet Formulations of Posaconazole for Prophylaxis of Invasive Fungal Infections

Posaconazole is used for prophylaxis for invasive fungal infections (IFIs) among patients with hematologic malignancies. We compared the incidence of breakthrough IFIs and early discontinuation between patients receiving delayed-release tablet and oral suspension formulations of posaconazole.

Posaconazole is used for prophylaxis for invasive fungal infections (IFIs) among patients with hematologic malignancies. We compared the incidence of breakthrough IFIs and early discontinuation between patients receiving delayed-release tablet and oral suspension formulations of posaconazole. This was a retrospective cohort study of patients receiving posaconazole between 1 January 2010 and 30 June 2016. We defined probable or proven breakthrough IFIs using the European Organization for Research and Treatment of Cancer (EORTC) criteria. Overall, 547 patients received 860 courses of posaconazole (53% received the oral suspension and 48% received the tablet); primary indications for prophylaxis were acute myeloid leukemia (69%), graft-versus-host disease (18%), and myelodysplastic syndrome (3%). There were no significant differences in demographics or indications between patients receiving the different formulations. The incidence and incidence rate of probable or proven IFIs were 1.6% and 3.2 per 10,000 posaconazole days, respectively. There was no significant difference in the rate of IFIs between suspension courses (2.8 per 10,000 posaconazole days) and tablet courses (3.7 per 10,000 posaconazole days) (rate ratio = 0.8, 95% confidence interval [CI] = 0.3 to 2.3). Of the 14 proven or probable cases of IFI, 8/14 had posaconazole serum concentrations measured, and the concentrations in 7/8 were above 0.7 μg/ml. Posaconazole was discontinued early in 15.5% of courses; however, the frequency of discontinuation was also not significantly different between the tablet (16.5%) and oral suspension (14.6%) formulations (95% CI for difference = −0.13 to 0.06). In conclusion, the incidence of breakthrough IFIs was low among patients receiving posaconazole prophylaxis and not significantly different between patients receiving the tablet formulation and those receiving the oral suspension formulation.

Therapy of Mucormycosis

Despite the recent introduction of mold-active agents (posaconazole and isavuconazole), in addition to amphotericin B products, to our armamentarium against mucormycosis, many uncertainties remain for the management of this uncommon opportunistic infection, as there are no data from prospective randomized clinical trials to guide therapy. In this mini-review, we present the current status of treatment options. In view of the heterogeneity of the disease (different types of affected hosts, sites of infection, and infecting Mucorales), mucormycosis management requires an individualized management plan that takes into account the net state of immunosuppression of the host, including comorbidities, certainty of diagnosis, site of infection, and antifungal pharmacological properties.

Low dose posaconazole delayed release tablets for fungal prophylaxis in lung transplant recipients

In November 2013, posaconazole delayed release (DR) tablets were approved by the FDA with the labeled dose of 300 mg daily for fungal prophylaxis. There are no studies demonstrating the appropriate dose in lung transplant recipients (LTR). We performed a 2-center retrospective cohort study of LTR taking posaconazole DR tablets for prophylaxis between January 2014 and January 2017. Mean serum trough concentrations and percentage of measurements ≥0.7 mcg/mL were compared by daily dose. Forty-nine subjects with 156 steady state serum posaconazole concentrations were included. There was a significant difference in percentage of first measured concentration ≥0.7 mcg/mL by initial daily dose (P = .04). The mean serum posaconazole concentration by dose was 0.9 (±0.42) mcg/mL for 100 mg daily, 1.66 (±0.91) mcg/mL for 200 mg daily, 2.39 (±1.49) mcg/mL for 300 mg daily, and 1.75 (±0.21) mcg/mL for 400 mg daily (P < .001). Mean concentrations were at goal in 63.3%, 96.9%, 94.9%, and 100% of subjects taking 100 mg, 200 mg, 300 mg, and 400 mg daily respectively (P = .04). Our results suggest that doses less than 300 mg daily of posaconazole DR tablets may be adequate to achieve target serum concentrations in LTR. Larger studies are needed to confirm these findings.

Invasive fungal infections in high-risk patients: report from TIMM-8 2017

Trends in Medical Mycology (TIMM) is the biennial meeting of the Infectious Disease Group of the European Organisation for Research and Treatment of Cancer (EORTC) and the European Confederation of Medical Mycology (ECMM). It brings together clinicians and researchers from across the world to share the latest R&Ds in medical mycology. Despite advances in treatment, invasive fungal infections remain a major cause of morbidity and mortality in certain high-risk groups of patients, particularly in immunocompromised patients, including those undergoing solid organ transplantation and those with acute leukemia. The challenges for clinicians are now compounded by the rapid development of multidrug resistance. The latest data and approaches to identifying patients at high risk for invasive fungal infections, ensuring early diagnosis and achieving effective treatment, including when and how to use therapeutic drug monitoring with azoles, were shared with >1000 clinicians and researchers from around the world attending the eighth TIMM, held in Belgrade, Serbia, in October 2017 (TIMM-8 2017).

Antifungal Prophylaxis with Posaconazole Delayed-Release Tablet and Oral Suspension in a Real-Life Setting: Plasma Levels, Efficacy, and Tolerability

We continuously determined posaconazole plasma concentrations (PPCs) in 61 patients with hematological malignancies receiving posaconazole (PCZ) delayed-release tablets (DRT; 48 patients; median duration of intake, 92 days) and PCZ oral solution (OS; 13 patients; median duration of intake, 124 days). PCZ DRT and OS antifungal prophylaxis was efficient and well tolerated. Thirty-four of 48 patients (71%) receiving DRT always had PPCs of >0.7 mg/liter, while 14 of 48 patients (29%) had at least one PPC of ≤0.7 mg/liter. In patients receiving OS, 4 of 13 patients (31%) always had PPCs of >0.7 mg/liter, 6 of 13 patients (46%) had at least one PPC of ≤0.7 mg/liter, and 3 (23%) patients never reached a PPC of 0.7 mg/liter. In patients with at least one determined PPC, the mean proportion of all PPCs of >0.7 mg/liter was 91% for PCZ DRT, whereas it was 52% for PCZ OS (P = 0.001). In the per sample analysis, PPCs were significantly more likely to be >0.7 mg/liter in patients receiving DRT than in patients receiving OS (PPCs were >0.7 mg/liter in 91.4% [297/325] of patients receiving DRT versus 70.3% [85/121] of patients receiving OS; P < 0.001). Patients receiving PCZ DRT had higher proportions of PPCs of >0.7 mg/liter than patients receiving OS both in the per patient and in the per sample analyses. Two patients (3%) had side effects during PCZ prophylaxis, and one (2%) had fungal breakthrough infection. Therapeutic drug monitoring enables detection of extended periods of PPCs of ≤0.7 mg/liter (e.g., due to nonadherence or graft-versus-host disease), which may also be associated with the loss of protective intracellular PCZ concentrations, regardless of the PCZ formulation.

[Invasive pulmonary aspergillosis]

INTRODUCTION

Invasive pulmonary aspergillosis (IPA) is an important cause of morbidity and mortality in a wide range of patients. Early recognition and diagnosis have become a major focus in improving the management and outcomes of this life-threatening disease.

BACKGROUND

IPA typically occurs during a period of severe and prolonged neutropenia. However, solid organ transplant recipients, patients under immunosuppressive therapy or hospitalized in intensive care units are also at risk. The diagnosis is suspected in the presence of a combination of clinical, biological and CT scan evidence. The microbiological diagnostic strategy should be adapted to the patient's profile. Conventional methods with culture and species identification remain the standard but early diagnosis has been improved by the use of biomarkers such as galactomannan antigen in serum or in bronchoalveolar lavage.

OUTLOOK

The epidemiology of IPA should change with the increased use of antifungal prophylactic regimens and the arrival of targeted therapies. Other microbiological tools, such as PCR and other biomarkers, are currently being assessed.

CONCLUSIONS

IPA must be considered in a wide range of patients. Its prognosis remains poor despite progress in the microbiological diagnosis and therapeutic management.

Prevention of Invasive Aspergillus Fungal Infections with the Suspension and Delayed-Release Tablet Formulations of Posaconazole in Patients with Haematologic Malignancies

Posaconazole is a triazole antifungal used to prevent invasive fungal infections (IFIs) in patients receiving chemotherapy or haemotopoietic stem cell transplantation. Due to highly variable bioavailability of the oral suspension formulation, a delayed-release tablet was developed which showed improved bioavailability. A minimal target posaconazole plasma concentration of 0.7 mg/L is recommended for prophylaxis of IFIs. However, the relationship between plasma concentration of posaconazole and its efficacy against IFIs remains unclear. We analysed trough posaconazole concentrations and response against IFIs in 50 and 104 patients with haematologic malignancies receiving prophylactic posaconazole as the tablet or suspension formulation, respectively. Mean plasma concentration of posaconazole was 1.91 ± 1.06 mg/L and 0.82 ± 0.57 mg/L in the tablet and the oral suspension group, respectively (p < 0.0001). The percentage of patients reaching the minimal target concentration of 0.7 mg/L was 92.0% and 47.1% in the tablet and oral suspension groups, respectively (p < 0.0001). Emergent aspergillosis occurred in 9 (8.7%) patients in the suspension group and in none of the patients taking the tablet formulation (p = 0.032). Our results show a relationship between plasma concentrations of posaconazole and its prophylactic efficacy in patients with haematologic malignancies. Target posaconazole concentrations are reached more efficiently with the tablet than with the suspension formulation.

Population Pharmacokinetics of Posaconazole Tablets and Monte Carlo Simulations To Determine whether All Patients Should Receive the Same Dose

Posaconazole is extensively used for prophylaxis for invasive fungal infections. The gastro-resistant tablet formulation has allowed the bioavailability issues encountered with the oral suspension to be overcome. However, overexposure is now frequent. This study aimed to (i) describe the pharmacokinetics of posaconazole tablets in a real-life cohort of patients with hematological malignancies and (ii) perform Monte Carlo simulations to assess the possibility that the daily dose can be reduced while keeping a sufficient exposure. Forty-nine consecutive inpatients were prospectively included in the study. Posaconazole trough concentrations (TC) were measured once a week, and biological and demographic data were collected. The concentrations were analyzed by compartmental modeling, and Monte Carlo simulations were performed using estimated parameters to assess the rate of attainment of the target TC after dose reduction. The pharmacokinetics of posaconazole were well described using a one-compartment model with first-order absorption and elimination. The values of the parameters (interindividual variabilities) were as follows: the absorption constant (k_a ) was 0.588 h^-1 (fixed), the volume of distribution (V/F) was 420 liters (28.2%), and clearance (CL/F) was 7.3 liters/h (24.2%) with 31.9% interoccasion variability. Forty-nine percent of the simulated patients had TC at steady state of ≥1.5 μg/ml and maintained a TC above 1 μg/ml after a reduction of the dose to 200 mg daily. A third of these patients eligible for a dose reduction had TC of ≥1.5 μg/ml as soon as 48 h of treatment. Though posaconazole tablets were less impacted by bioavailability issues than the oral suspension, the pharmacokinetics of posaconazole tablets remain highly variable. Simulations showed that approximately half of the patients would benefit from a reduction of the dose from 300 mg to 200 mg while keeping the TC above the minimal recommended target of 0.7 μg/ml, resulting in a 33% savings in the cost of this very expensive drug.

Foiling fungal disease post hematopoietic cell transplant: review of prophylactic strategies

Hematopoietic cell transplantation (HCT) offers definitive management for a wide variety of malignant and nonmalignant diseases. Conditioning regimens and therapies used to prevent and treat GvHD are immune suppressive, often increasing the risk of developing fungal disease due to yeasts or molds. Antifungal prophylaxis may be useful in preventing morbidity and mortality during and after HCT. In this article, we review the epidemiology and current literature regarding strategies for prevention of invasive fungal disease (IFD) in the pre-engraftment and post-engraftment settings, and propose future direction for scientific discovery.

Safety study and therapeutic drug monitoring of the oral tablet formulation of posaconazole in patients with haematological malignancies

PURPOSE

Posaconazole is a triazole antifungal widely used for prophylaxis of invasive fungal disease (IFI). Posaconazole tablets allow reaching higher plasma levels than the oral suspension, but safety data with this formulation in real life are scarce. This study aimed at evaluating the safety profile, the pharmacokinetic variability, and the concentration-toxicity relationship of posaconazole tablets in patients with haematological malignancies.

METHODS

Sixty neutropenic patients treated with posaconazole tablets for prophylaxis of IFI were prospectively included in the study. Adverse drug reactions (ADR) were recorded and analyzed by the Regional Pharmacovigilance Centre to assess posaconazole implication. Blood samples were drawn once a week and plasma trough concentrations (C _min) were assayed by LC-MS/MS. The rates of ADR by quartile of C _min were compared.

RESULTS

Eighteen patients (30%) experienced at least one ADR attributed to posaconazole. Liver function test (LFT) abnormalities were encountered in 20% of patients and resulted in four (6.7%) treatment discontinuations. Posaconazole median (range) C _min was 1.36 (< 0.1-3.44) µg/mL (inter-patient CV = 43.9%). During follow-up, 28.6% of patients had at least one concentration < 0.7 µg/mL, and 35.7% had at least one concentration > 2 µg/mL. Rates of ADR by quartile of C _min were not different.

CONCLUSIONS

Posaconazole was well tolerated; however, LFT abnormalities were frequent. ADR occurrence was not linked to posaconazole exposure. Because posaconazole concentrations were highly variable, TDM can be helpful to avoid underexposure to the drug and increase its efficacy in preventing IFI. Conversely, a large proportion of patients was overexposed and might have benefited of a dose reduction.

Chromoblastomycosis

Chromoblastomycosis (CBM), also known as chromomycosis, is one of the most prevalent implantation fungal infections, being the most common of the gamut of mycoses caused by melanized or brown-pigmented fungi. CBM is mainly a tropical or subtropical disease that may affect individuals with certain risk factors around the world. The following characteristics are associated with this disease: (i) traumatic inoculation by implantation from an environmental source, leading to an initial cutaneous lesion at the inoculation site; (ii) chronic and progressive cutaneous and subcutaneous tissular involvement associated with fibrotic and granulomatous reactions associated with microabscesses and often with tissue proliferation; (iii) a nonprotective T helper type 2 (Th2) immune response with ineffective humoral involvement; and (iv) the presence of muriform (sclerotic) cells embedded in the affected tissue. CBM lesions are clinically polymorphic and are commonly misdiagnosed as various other infectious and noninfectious diseases. In its more severe clinical forms, CBM may cause an incapacity for labor due to fibrotic sequelae and also due to a series of clinical complications, and if not recognized at an early stage, this disease can be refractory to antifungal therapy.

Antifungal stewardship considerations for adults and pediatrics

Antifungal stewardship refers to coordinated interventions to monitor and direct the appropriate use of antifungal agents in order to achieve the best clinical outcomes and minimize selective pressure and adverse events. Antifungal utilization has steadily risen over time in concert with the increase in number of immunocompromised adults and children at risk for invasive fungal infections (IFI). Challenges in diagnosing IFI often lead to delays in treatment and poorer outcomes. There are also emerging data linking prior antifungal exposure and suboptimal dosing to the emergence of antifungal resistance, particularly for Candida. Antimicrobial stewardship programs can take a multi-pronged bundle approach to ensure suitable prescribing of antifungals via post-prescription review and feedback and/or prior authorization. Institutional guidelines can also be developed to guide diagnostic testing in at-risk populations; appropriate choice, dose, and duration of antifungal agent; therapeutic drug monitoring; and opportunities for de-escalation and intravenous-to-oral conversion.

In Vivo 11β-Hydroxysteroid Dehydrogenase Inhibition in Posaconazole-Induced Hypertension and Hypokalemia

We describe a case of apparent mineralocorticoid excess (AME) secondary to posaconazole therapy and suggest the biochemical mechanism. Clinical and laboratory investigation confirmed 11β-hydroxysteroid dehydrogenase inhibition and withholding therapy led to a resolution of all clinical and laboratory abnormalities. Posaconazole was later restarted at a lower dose and prevented recurrence of this syndrome. Additional studies are necessary to determine the frequency of posaconazole-induced AME and whether other azole antifungals can be associated with this phenomenon.

Periprosthetic hip joint infection with Aspergillus terreus: A clinical case and a review of the literature

Fungal periprosthetic joint infections due to Aspergillus species are rare but are associated with significant cost and morbidity. We present a case of Asperigillus terreus prosthetic joint infection of the hip. The patient was successfully treated with a prolonged course of systemic antifungals along with surgical management.

Real-Life Assessment of the Safety and Effectiveness of the New Tablet and Intravenous Formulations of Posaconazole in the Prophylaxis of Invasive Fungal Infections via Analysis of 343 Courses

Posaconazole is the preferred mold-active azole for prophylaxis against invasive fungal infections (IFIs) in patients with hematological malignancy. Delayed-release tablet and intravenous formulations of posaconazole have recently become available, but clinical data are limited. We sought to examine the real-world pharmacokinetics and prophylactic effectiveness of the new formulations of posaconazole given as prophylaxis for patients with hematological malignancy. A retrospective cohort of all consecutive adult inpatients with hematological malignancy who received ≥3 days of tablet or intravenous posaconazole therapy for primary IFI prophylaxis at the M. D. Anderson Cancer Center between 1 December 2013 and 31 December 2015 was established. Clinical information was collected and correlated with low posaconazole serum levels (<700 ng/ml). Rates of IFIs and safety events were assessed. A total of 1,321 courses of posaconazole were administered at the M. D. Anderson Cancer Center during the study period, of which 343 courses were assessed for prophylactic safety and effectiveness. Seventy-nine patients (23%) had posaconazole serum level measurements available for interpretation. Acute myeloid leukemia was the primary malignancy (62%), with 20% of all patients having previously received a stem cell transplant. The median posaconazole level was 1,380 ng/ml (interquartile range, 864 to 1,860 ng/ml). Low posaconazole levels (<700 ng/ml) were observed for 14 patients (18%). Proven or probable breakthrough IFIs occurred in 8 patients (2%); posaconazole therapeutic drug monitoring (TDM) was performed for 6 of those patients, all with levels above 700 ng/ml. Overall, 19% of patients experienced grade 3 or 4 liver injury, manifesting primarily as hyperbilirubinemia and being correlated with serum levels of >1,830 ng/ml. Although hepatotoxicity in a small percentage of patients is of concern, posaconazole tablets appeared to be generally safe and effective. As all breakthrough IFIs for which TDM was performed occurred in patients with levels of >700 ng/ml, and a posaconazole level of >1,830 ng/ml was correlated with grade 3 or 4 liver toxicity, further studies are needed to assess the role of TDM.