Prospective Cohort Study of Micafungin Population Pharmacokinetic Analysis in Plasma and Peritoneal Fluid in Septic Patients with Intra-abdominal Infections.

The objective of this study was to describe the pharmacokinetics (PK) of micafungin in plasma and peritoneal fluid in septic patients with intra-abdominal infections. Twelve patients with secondary peritonitis in septic shock receiving 100 mg micafungin once daily were included. Total micafungin plasma and peritoneal fluid were subjected to a population pharmacokinetic analysis using Pmetrics. Monte Carlo simulations were performed considering the total area under the curve from 0 to 24 h (AUC0-24)/MIC ratios in plasma. Micafungin concentrations in both plasma and the peritoneal exudate were best described by a three-compartmental PK model with the fat-free mass (FFM) as a covariate of clearance (CL) and the volume of the central compartment (Vc). The mean parameter estimates (standard deviations [SD]) were 1.18 (0.40) liters/h for CL and 12.85 (4.78) liters for Vc. The mean peritoneal exudate/plasma ratios (SD) of micafungin were 25% (5%) on day 1 and 40% (8%) between days 3 and 5. Dosing simulations supported the use of standard 100-mg daily dosing for Candida albicans (FFM, <60 kg), C. glabrata (FFM, <50 kg), and C. tropicalis (FFM, <30 kg) on the second day of therapy. There is a moderate penetration of micafungin into the peritoneal cavity (25 to 40%). For empirical treatment, a dose escalation of at least a loading dose of 150 mg depending on the FFM of patients and the Candida species is suggested to be effective from the first day of therapy.

Drug-Induced Liver Injury (DILI) With Micafungin: The Importance of Causality Assessment.

Background: Micafungin is increasingly used in the treatment and prevention of candidiasis in hospitalized patients. Limited data are available from which to assess the risk of drug-induced liver injury (DILI) with micafungin. No studies, to date, have applied a standardized causality assessment method to the study of micafungin-associated DILI. Objective: This study aimed to identify the frequency and clinical pattern of DILI in micafungin-treated patients as determined using 2 standardized causality assessment algorithms. Methods: A retrospective analysis was conducted of micafungin-treated patients at a single center between May 15, 2017, and May 15, 2018. DILI was defined on the basis of liver test elevations and the presence of associated signs and symptoms. The Roussel UClaf Causality Assessment Method (RUCAM) and the Naranjo algorithm were applied to each case. Results: A total of 99 patients were assessed; 52 were excluded, with a final sample of 47 evaluable patients. The definition of DILI was met in 9 (19%) patients, with a clinical pattern consistent with cholestatic injury in 7 of 9 (78%) patients. No cases were associated with jaundice. Agreement between the 2 causality assessment methods occurred in 4 of 9 (44%) cases. Application of the RUCAM algorithm led to the exclusion of 4 cases, resulting in a final reported prevalence of micafungin-associated DILI of 10.6%. Conclusion and Relevance: Asymptomatic DILI was identified in 10.6% of micafungin-treated patients. The choice of a causality assessment nomogram substantially influenced the determination of DILI prevalence. Compared with the Naranjo algorithm, the RUCAM algorithm is recommended as a more precise tool of assessing the relationship between drug exposure and DILI.

Economic evaluation of micafungin versus liposomal amphotericin B (LAmB) for treating patients with candidaemia and invasive candidiasis (IC) in Turkey.

Micafungin was reported to be non-inferior to liposomal amphotericin B (LAmB) in treating patients with candidaemia and invasive candidiasis (IC). The current study aimed to evaluate the economic impact of using micafungin versus LAmB for treatment of candidaemia and IC in Turkey. A decision analytic model, which depicted economic consequences upon administration of micafungin or LAmB for treating patients with candidaemia and IC in the Turkish hospitals, was constructed. Patients were switched to an alternative antifungal agent if initial treatment failed due to mycological persistence. All patients were followed up until treatment success or death. Outcome probabilities were obtained from published literature and cost inputs were derived from the latest Turkish resources. Expert panels were used to estimate data that were not available in the literature. Cost per patient treated for each intervention was then calculated. Sensitivity analyses including Monte Carlo simulation were performed. For treatment of candidaemia and IC, micafungin (€4809) was associated with higher total cost than LAmB (€4467), with an additional cost of €341 per treated patient. Cost of initial antifungal treatment was the major cost driver for both comparators. The model outcome was robust over a wide variation in input variables except for drug acquisition cost and duration of initial antifungal treatment with micafungin or LAmB. LAmB is cost-saving relative to micafungin for the treatment of candidaemia and IC from the Turkish hospital perspective, with variation in drug acquisition cost of the critical factor affecting the model outcome.

Rapid species identification of Candida directly from blood culture broths by Sepsityper-MALDI-TOF mass spectrometry: impact on antifungal therapy.

Rapid identification of Candida species facilitates pathogen-directed therapy with either fluconazole or an echinocandin. METHOD: We applied Sepsityper matrix-assisted laser desorption ionisation time of flight mass spectrometry (MALDI-TOF-MS) technology on positive blood culture broths for rapid species identification. RESULTS: Of the 74 patients with candidaemia, 25 had the species identified on the day of the positive blood culture directly from the broth (rapid identification group) while the remaining 49 had the species identified from culture (conventional identification group). Three (13.6%) out of 22 treated patients in the rapid identification group received echinocandin compared to 20/45 (44.4%) in the conventional identification group. The appropriateness of therapy was 90.9% in the rapid identification group and 62.2% in the conventional identification group (p = 0.01). Cost savings were more than £10,000 in the first three days of treatment. CONCLUSION: Sepsityper-MALDI-TOF-MS is a useful tool in supporting antifungal stewardship programmes.

Exposure-Response Analysis of Micafungin in Neonatal Candidiasis: Pooled Analysis of Two Clinical Trials.

BACKGROUND: Neonatal candidiasis causes significant morbidity and mortality in high risk infants. The micafungin dosage regimen of 10 mg/kg established for the treatment of neonatal candidiasis is based on a laboratory animal model of neonatal hematogenous Candida meningoencephalitis and pharmacokinetic (PK)-pharmacodynamic (PD) bridging studies. However, little is known about the how these PK-PD data translate clinically. METHODS: Micafungin plasma concentrations from infants were used to construct a population PK model using Pmetrics software. Bayesian posterior estimates for infants with invasive candidiasis were used to evaluate the relationship between drug exposure and mycologic response using logistic regression. RESULTS: Sixty-four infants 3-119 days of age were included, of which 29 (45%) infants had invasive candidiasis. A 2-compartment PK model fits the data well. Allometric scaling was applied to clearance and volume normalized to the mean population weight (kg). The mean (standard deviation) estimates for clearance and volume in the central compartment were 0.07 (0.05) L/h/1.8 kg and 0.61 (0.53) L/1.8 kg, respectively. No relationship between average daily area under concentration-time curve or average daily area under concentration-time curve:minimum inhibitory concentration ratio and mycologic response was demonstrated (P > 0.05). Although not statistically significant, mycologic response was numerically higher when area under concentration-time curves were at or above the PD target. CONCLUSIONS: While a significant exposure-response relationship was not found, PK-PD experiments support higher exposures of micafungin in infants with invasive candidiasis. More patients would clarify this relationship; however, low incidence deters the feasibility of these studies.