Isavuconazole: A new broad-spectrum azole. Part 2: pharmacokinetics and clinical activity.

Isavuconazole, the active moiety of its prodrug isavuconazonium, is a new extended-spectrum triazole whose activity against yeasts, molds, including Aspergillus and mucorales, and dimorphic fungi has been shown in vitro and in preclinical models. The most relevant pharmacokinetics features are water-solubility of the prodrug, rapid cleavage of the prodrug into active moiety and cleavage product by plasmatic esterases, high oral bioavailability of isavuconazole with an extensive penetration into most tissues and a good safety profile even in case of renal impairment. The results of two main clinical studies have led to an approval by FDA and EMA in the treatment of invasive aspergillosis and invasive mucormycosis. Isavuconazole is non-inferior to voriconazole in terms of response and survival in invasive aspergillosis and has shown improved safety and tolerability. Importantly, less hepatobiliary, skin and eye disorders have been reported in isavuconazole-treated patients. Isavuconazole has therefore been granted a grade A-I recommendation by the European Conference on Infections in Leukemia (ECIL) for the treatment of invasive aspergillosis. Efficacy has also been demonstrated in mucormycosis in an open-label study. Survival was similar to the survival of matched patients from the international Fungiscope registry and treated with an amphotericin B formulation. Isavuconazole failed to show non-inferiority to caspofungin in a large double-blind candidemia trial. The aim of this review is to give the reader an overview of the data available so far to support inclusion of isavuconazole in the anti-mold therapeutic arsenal.

Isavuconazole: A new broad-spectrum azole. Part 1: In vitro activity.

Triazoles compounds are first-line agents for the treatment of invasive fungal diseases. Isavuconazole is the most recent triazole compound, approved in 2015 by the FDA and the EMA to treat invasive aspergillosis and mucormycosis. We reviewed here the in vitro activity of isavuconazole against a vast spectrum of species. Isavuconazole MICs were evaluated using CLSI, EUCAST or Etest methods, with no significant differences between the technics. Low MIC50 and MIC90 (<1µg/mL) were described for isavuconazole against the majority of Candida spp., except for C. glabrata and C. krusei. In vitro activity against Aspergillus spp. varied according to the species with an overall MIC90 of 1µg/mL ranging from 0.125µg/mL (A. fumigatus) to 16µg/mL (A. niger, A. tubingiensis). As for Aspergillus, the activity of isavuconazole against agents of mucormycosis varies upon genus and species, with an overall MIC90 from 4 (Rhizopus spp.) to 16µg/mL (Rhizomucor spp. and Mucor spp.). Recently, to help detecting non-wild-type isolates, EUCAST committee has proposed ECOFFs values for C. albicans, C. parapsilosis and C. tropicalis (0.03µg/mL), for Aspergillus fumigatus (2µg/mL), A. nidulans (0.25µg/mL), A. terreus (1µg/mL), A. flavus (2µg/mL) and A. niger (4µg/mL). Moreover, clinical breakpoints (susceptible/resistant) were defined for Aspergillus fumigatus (1µg/mL), A. nidulans (0.25µg/mL) and A. terreus (1µg/mL). Using these breakpoints, isavuconazole showed activity against the vast majority of fungi.

Assessment of high-priced systemic antifungal prescriptions.

OBJECTIVES: To assess compliance with international guidelines for costly antifungal prescriptions and to compare these results with a first study performed in 2007. METHODS: Retrospective study including all costly antifungal prescriptions made in surgical and medical intensive care units and in a hepatobiliary, pancreatic, and digestive surgery unit. Prescriptions were assessed in terms of indication, dosage, and antifungal de-escalation. RESULTS: Seventy-four treatments were analyzed. Treatments were prescribed for prophylactic (1%), empirical (22%), pre-emptive (16%), or targeted therapy (61%). Caspofungin accounted for 68% of prescriptions, followed by voriconazole (20%) and liposomal amphotericin B (12%). Indication was appropriate in 91%, debatable in 1%, and inappropriate in 8%. Dosage was appropriate in 69%, debatable in 8%, and inappropriate in 23%. Prescriptions were inappropriate for the following reasons: lack of dosage adjustment in light of the hepatic function (10 cases), underdosage or excessive dosage by>25% of the recommended dose in seven cases. De-escalation to fluconazole was implemented in 40% of patients presenting with a fluconazole-susceptible candidiasis. CONCLUSION: The overall incidence of appropriate use was higher in 2012 compared with 2007 (62% and 37% respectively, P=0.004). Nevertheless, costly antifungal prescriptions need to be optimized in particular for empirical therapy, dosage adjustment, and potential de-escalation to fluconazole.

[Feedback on the evaluation of clinical pharmacy activities developed in surgery]. / Retour d'expérience sur l'évaluation des activités de pharmacie clinique développées en chirurgie.

INTRODUCTION: Our current development strategy integrates clinical pharmacy activities prioritized in surgical services. Patients in these services are typically risk patients: transfers, multiple prescribers, frequent medication change, pharmacotherapeutic risk classes. PATIENTS AND METHODS: Three clinical pharmacy activities (admission reconciliation, pharmaceutical analysis, participation doctors round) have been developed in orthopaedic surgery and neurosurgery. Pharmacists prospectively recorded data describing their activities: number of reconciliations and analyzed requirements and time required to achieve them. Data on pharmaceutical interventions were recorded on the basis ActIP®. The clinical significance of interventions was retrospectively rated by a team of two pharmacists and two physicians on the scale adapted Hatoum et al. RESULTS: Four thousand five hundred pharmaceutical analysis and 248 reconciliations were conducted. One hundred and fifty-six pharmaceutical interventions were issued. The average acceptance rate was 80%. A total of 5.8% of pharmaceutical interventions have been listed with a very significant clinical importance and 48.1% with at least significant clinical importance. The activities and documentation required pharmaceutical average daily time (senior pharmacist, resident and external pharmacist) about 6 hours. DISCUSSION AND CONCLUSION: Other studies, including comparative and medico-economic, must be conducted to support these results. Nevertheless, the indicators obtained attend a better readability of the clinical importance of the activities performed by clinical pharmacists and this particularly in surgical services, both by prescribers and authorities.

[Clinical pharmacy and surgery: Review]. / Pharmacie clinique et chirurgie : revue de la littérature.

Clinical pharmacy has been developed and evaluated in various medical hospital activities. Reviews conducted in this area reported a higher value of this discipline. In surgical services, evenly adverse drug events may occur, so clinical pharmacy activities must also help to optimize the management of drug's patient. The objectives of this literature review is to determine the profile of clinical pharmacy activities developed in surgical services and identify indicators. The research was conducted on Pubmed(®) database with the following keywords (2000-2013), "surgery", "pharmacy", "pharmacist", "pharmaceutical care", "impact" and limited to French or English papers. Studies dealing on simultaneously medical and surgical areas were excluded. Twenty-one papers were selected. The most frequently developed clinical pharmacy activities were history and therapeutic drug monitoring (antibiotics or anticoagulants). Two types of indicators were identified: activity indicators with the number of pharmaceutical interventions, their description and clinical signification, the acceptance rate and workload. Impact indicators were mostly clinical and economic impacts. The development of clinical pharmacy related to surgical patients is documented and appears to have, as for medical patients, a clinical and economical value.

[Mechanisms of pharmacokinetic drug-drug interactions]. / Mécanismes des interactions médicamenteuses d'origine pharmacocinétique.

Pharmacokinetic drug-drug interactions occur when a drug alters the disposition (absorption, distribution, elimination) of a coadministered agent. Pharmacokinetic interactions may result in the increase or the decrease of plasma drug concentrations. These modifications are variable in intensity but can lead to contraindications of the association. The mechanisms of pharmacokinetic interactions involve drug metabolizing enzymes, drug transporters and orphan nuclear receptors that regulate at the transcriptional level the expression of enzymes and transporters. The increase of drug plasma concentrations is generally related to the inhibition of enzymes and/or drug transport. The decrease of drug concentrations reflects the activation of orphan nuclear receptors by inducers that lead to the increase of the expression of enzymes and drug transporters. Inhibition of drug metabolism or transport is quite immediate (24-48h) while induction is a slower process (7-10 days). Complex situations may be observed with drugs that are both inducers and inhibitors (rifampin, ritonavir). They can cause the decrease and the increase of the exposure of the combined agent depending on the duration of the association.

Combination of caspofungin and an azole or an amphotericin B formulation in invasive fungal infections.

OBJECTIVES: Combination of caspofungin and another anti-fungal agent raise expectation of improved efficacy in severe fungal infections including failures to first line therapy. METHODS: We assessed the efficacy and safety of a combination therapy including caspofungin in 17 immunosuppressed or postoperative patients progressive despite standard anti-fungal therapy. RESULTS: The infections included aspergillosis (6), invasive candidiasis (9), mucormycosis (1) and Scedosporium pneumonia (1). Infections had failed one to four prior lines of treatment. The anti-fungal agent combined to caspofungin was either an amphotericin B formulation or an azole. There were 12 favourable responses (71%) and five failures. The survival rate at 3 months was 47%. Eleven patients died within 2-533 days. The causes of death included the initial fungal infection (4), relapse of the infection after switching to oral monotherapy (2), breakthrough aspergillosis (1), and the underlying condition (4). Clinical and renal tolerance were good. Significant hepatic abnormalities were recorded in eight (50%) of the 16 patients evaluable for biological tolerance. CONCLUSION: Caspofungin combined with an azole or with amphotericin B may be of interest in the treatment of serious fungal infections after failure of conventional therapy. Close monitoring of hepatic function is required. These approach should be evaluated in prospective trials.

Clinical antifungal efficacy trials in invasive aspergillosis: Consensus standards for trial design and room for improvement.

Despite recent improvements in outcome of invasive aspergillosis there are still high failure and fatality rates. The trial comparing voriconazole to amphotericin B deoxycholate has become a reference for clinical trials in invasive aspergillosis due to the large number of patients included, the use of definition criteria close to the international consensus criteria, the inclusion of the halo sign on chest computed tomography for the definition of probable cases, the extensive review of the data by a panel of experts including radiologists, and most important, the successful efficacy results. Similar strict methodology for eligibility and assessment of outcome has been applied in the recently completed liposomal amphotericin B trial. This study compared a standard daily dose of liposomal amphotericin B (3 mg/kg) versus a high loading dose (10 mg/kg/d). The option to include possible cases in this trial and to give the investigators a few days to upgrade the diagnosis to a probable or definite level proved to be an effective strategy, saving four months in the duration of the recruitment period. Additional progress can be expected in future trials with the use of a standardized cutoff for the galactomannan detection test and a stratification at randomization on the most critical prognostic factor such as progressive underlying malignancy or allogeneic stem cell transplantation.

Management of systemic fungal infections: alternatives to itraconazole.

For many years, amphotericin B and flucytosine have been the only antifungal agents for invasive fungal infections. Amphotericin B was the standard of care for most of these infections. However, its use was often associated with low efficacy and poor tolerance. Fortunately, the antifungal armamentarium has increased during the past two decades with the addition of several new agents. In addition to itraconazole and fluconazole, lipid formulations of amphotericin B, voriconazole, caspofungin and micafungin have arrived on the market. Other agents are expected to be licensed shortly (anidulafungin, posaconazole). These various antifungal agents differ in their spectrum, pharmacokinetic profile, route of administration, efficacy in clinical trials, safety profile, drug-drug interactions and, importantly, their cost. There is no longer a unique standard agent for all or nearly all invasive fungal infections but a real choice among several agents. The characteristics of these new agents are reviewed to help clinicians in their decision to select an antifungal agent for their patients.