Evaluation of sulfobutylether-β-cyclodextrin (SBECD) accumulation and voriconazole pharmacokinetics in critically ill patients undergoing continuous renal replacement therapy

Edoxaban pharmacokinetics during in vitro continuous renal replacement therapy

BACKGROUND

To evaluate the clearance of edoxaban during modeled in vitro continuous renal replacement therapy (CRRT), assess protein binding and circuit adsorption, and provide initial dosing recommendations.

METHODS

Edoxaban was added to the CRRT circuit and serial pre-filter bovine blood samples were collected along with post-filter blood and effluent samples. All experiments were performed in duplicate using continuous veno-venous hemofiltration (CVVH) and hemodialysis (CVVHD) modes, with varying filter types, flow rates, and point of CVVH replacement fluid dilution. Concentrations of edoxaban and urea were quantified via liquid chromatography-tandem mass spectrometry. Plasma pharmacokinetic parameters for edoxaban were estimated via noncompartmental analysis. Two and three-way analysis of variance (ANOVA) models were built to assess the effects of mode, filter type, flow rate, and point of dilution on CLCRRT. Linear regression was utilized to provide dosing estimations across CRRT effluent flow rates from 0.5 to 5 L/h. Optimal edoxaban doses were suggested using CLCRRT and population non-renal clearance (CLNR) to estimate total clearance and match the systemic AUC associated with efficacy in the treatment of venous thromboembolism.

RESULTS

Edoxaban clearance from the CRRT circuit occurred primarily via hemofilter adsorption to the HF1400 and M150 filters at 74% and 65%, respectively, while mean percent protein binding was 41%. Multivariate analyses confirmed the lack of influence of CRRT mode, filter type, and point of dilution on the CLCRRT of edoxaban allowing dosing recommendations to be made based on effluent flow rate. Edoxaban doses of 30-45 mg once daily were estimated to achieve target the AUC threshold for flow rates from 0.5 to 5 L/h.

CONCLUSION

For CRRT flow rates most employed in clinical practice, an edoxaban dose of 45 mg once daily is predicted to achieve target systemic exposure thresholds for venous thromboembolism treatment. The safety and efficacy of this proposed dosing warrants further investigation in clinical studies.

Pharmacokinetics and pharmacodynamics of cyclodextrin-based oral drug delivery formulations for disease therapy

Oral drug administration has become the most common and preferred mode of disease treatment due to its good medication adherence and convenience. For orally administered drugs, the safety, efficacy, and targeting ability requirements have grown as disease treatment research advances. It is difficult to obtain prominent efficacy of traditional drugs simply via oral administration. Numerous studies have demonstrated that cyclodextrins (CDs) can improve the clinical applications of certain orally administered drugs by enhancing their water solubility and masking undesirable odors. Additionally, deeper studies have discovered that CDs can influence disease treatment by altering the drug pharmacokinetics (PK) or pharmacodynamics (PD). This review highlights recent research progress on the PK and PD effects of CD-based oral drug delivery in disease therapy. Firstly, the review describes the characteristics of current drug delivery modes in oral administration. Besides, we minutely summarized the different CD-containing drugs, focusing on the impact of CD-based alterations in PK or PD of orally administered drugs in treating diseases. Finally, we deeply discussed current challenges and future opportunities with regard to PK and PD of CD-based oral drug delivery formulations.

Candidemia in Adult Patients in the ICU: A Reappraisal of Susceptibility Testing and Antifungal Therapy

OBJECTIVE

To provide updates on the epidemiology and recommendations for management of candidemia in patients with critical illness.

DATA SOURCES

A literature search using the PubMed database (inception to March 2023) was conducted using the search terms "invasive candidiasis," "candidemia," "critically ill," "azoles," "echinocandin," "antifungal agents," "rapid diagnostics," "antifungal susceptibility testing," "therapeutic drug monitoring," "antifungal dosing," "persistent candidemia," and "Candida biofilm."

STUDY SELECTION/DATA EXTRACTION

Clinical data were limited to those published in the English language. Ongoing trials were identified through ClinicalTrials.gov.

DATA SYNTHESIS

A total of 109 articles were reviewed including 25 pharmacokinetic/pharmacodynamic studies and 30 studies including patient data, 13 of which were randomized controlled clinical trials. The remaining 54 articles included fungal surveillance data, in vitro studies, review articles, and survey data. The current 2016 Infectious Diseases Society of America (IDSA) Clinical Practice Guideline for the Management of Candidiasis provides recommendations for selecting empiric and definitive antifungal therapies for candidemia, but data are limited regarding optimized dosing strategies in critically ill patients with dynamic pharmacokinetic changes or persistent candidemia complicated.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

Outcomes due to candidemia remain poor despite improved diagnostic platforms, antifungal susceptibility testing, and antifungal therapy selection for candidemia in critically ill patients. Earlier detection and identification of the species causing candidemia combined with recognition of patient-specific factors leading to dosing discrepancies are crucial to improving outcomes in critically ill patients with candidemia.

CONCLUSIONS

Treatment of candidemia in critically ill patients must account for the incidence of non-albicans Candida species and trends in antifungal resistance as well as overcome the complex pathophysiologic changes to avoid suboptimal antifungal exposure.

Contribution of voriconazole N-oxide plasma concentration measurements to voriconazole therapeutic drug monitoring in patients with invasive fungal infection

BACKGROUND

Voriconazole (VRC), a widely used triazole antifungal, exhibits significant inter- and intra-individual pharmacokinetic variability. The main metabolite voriconazole N-oxide (NOX) can provide information on the patient's drug metabolism capacity.

OBJECTIVES

Our objectives were to implement routine measurement of NOX concentrations and to describe the metabolic ratio (MR), and the contribution of the MR to VRC therapeutic drug monitoring (TDM) by proposing a suggested dosage-adjustment algorithm.

PATIENTS AND METHODS

Sixty-one patients treated with VRC were prospectively included in the study, and VRC and NOX levels were assayed by LC-MS/MS. A mixed logistic model on repeated measures was implemented to analyse risk factors for the patient's concentration to be outside the therapeutic range.

RESULTS

Based on 225 measurements, the median and interquartile range were 2.4 μg/ml (1.2; 4.2), 2.1 μg/ml (1.5; 3.0) and 1.0 (0.6; 1.9) for VRC, NOX and the MR, respectively. VRC C_min <2 μg/ml were associated with a higher MR during the previous visit. MR values >1.15 and <0.48 were determined to be the best predictors for having a VRC C_min lower than 2 μg/ml and above 5.5 μg/ml, respectively, at the next visit.

CONCLUSIONS

Measurement of NOX resulted useful for TDM of patients treated with VRC. The MR using NOX informed interpretation and clinical decision-making and is very interesting for complex patients. VRC phenotyping based on the MR is now performed routinely in our institution. A dosing algorithm has been suggested from these results.

Is remdesivir safe in patients with renal impairment? Experience at a large tertiary urban medical center

PURPOSE

Remdesivir is FDA-approved for treatment of patients hospitalized with COVID-19 pneumonia, but not recommended in patients with severe renal failure. This study aims to evaluate the safety of remdesivir in this patient population.

METHODS

This was a single-center, retrospective cohort study including patients ≥ 18 years old, admitted between May 1, 2020 and April 30, 2021 who received remdesivir. Patients were divided into two groups: estimated creatinine clearance (eCrCl) < 30 mL/min and eCrCl ≥ 30 ml/min. Primary outcomes were development of acute kidney injury (AKI) after remdesivir initiation and hepatotoxicity (alanine aminotransferase [ALT] or aspartate aminotransferase [AST] > 5 × upper limit of normal) both at end of treatment (EOT) or 5 days after EOT. Secondary outcomes were length of stay (days) and mortality.

RESULTS

513 patients were assessed with 416 patients included in the study (eCrCl < 30 mL/min, n = 55; eCrCl ≥ 30 mL/min n = 361). Incidence of AKI (eCrCl < 30 mL/min 11% vs eCrCl ≥ 30 mL/min 7%, OR 1.57, 95% CI 0.57, 4.3) and hepatotoxicity (ALT: 2% vs 4%, OR 0.47, 95% CI 0.05, 3.7 and AST: 2% vs 2%, OR 1.26, 95% CI 0.14, 11.04) were similar between the two groups. Length of stay was longer in the eCrCl < 30 mL/min group (mean 18.6 vs 11.9, difference 6.7, 95% CI 3.8, 9.6), and no difference in mortality was observed (21.8% vs 18.8%, OR 1.2, 95% CI 0.6, 2.4).

CONCLUSION

Remdesivir was not associated with development of AKI or hepatotoxicity in patients with eCrCl < 30 mL/min compared to patients with eCrCl ≥ 30 mL/min, and warrants further investigation.

Treatment of Severe COVID-19 Infection With Remdesivir in Peritoneal Dialysis

End-stage kidney disease (ESKD) has been shown to be correlated with an increased risk of COVID-19 infection and mortality. Remdesivir is an effective non-EUA U.S. Food and Drug Administration (FDA)-approved antiviral agent for the treatment of COVID-19 in hospitalized adult and pediatric patients, though a lack of data has prevented its use in patients with severe kidney disease including dialysis patients. Some observational studies report the use of remdesivir in hemodialysis patients, but there are no reports of patients treated with remdesivir on peritoneal dialysis. Dialysis modalities may affect drug pharmacokinetics, and safety and efficiency of remdesivir in peritoneal dialysis is unknown. We report the first case, to our knowledge, of using remdesivir in a patient treated with peritoneal dialysis with no significant adverse events. This case illustrates the potential for remdesivir to be considered in peritoneal dialysis patients with severe COVID infection. Proper risk analysis and careful monitoring should be done, given the unpredictable clearance of the drug.

Pharmacovigilance of triazole antifungal agents: Analysis of the FDA adverse event reporting system (FAERS) database

Triazole antifungal drugs (TAD) are widely used to treat invasive fungal infections due to their broad antifungal spectrum and low toxicity. Despite their preference in the clinic, multiple Adverse Events (AE) are still reported each year.

OBJECTIVE

We aimed to characterize the distribution of Adverse Events associated with Triazole antifungal drugs in different systems and to identify Important Medical Events (IME) signals for Triazole antifungal drugs.

METHODS

The U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) was queried for Adverse Events related to Triazole antifungal drugs from 2012 to 2022. The Adverse Events caused by all other drugs and non-TAD antifungal drugs were analyzed as references. Reporting odds ratio and Bayesian confidence propagation neural network of information components were used to evaluate the association between Triazole antifungal drugs and Important Medical Events. Visual signal spectrum is mapped to identify potential adverse reaction signals.

RESULTS

Overall, 10,262 Adverse Events were reported to be associated with Triazole antifungal drugs, of which 5,563 cases were defined as Important Medical Events. Common adverse drug reactions (ADR) mentioned in the instructions such as delirium and hypokalemia were detected, as well as unlabeled ADRs such as rhabdomyolysis and hepatitis fulminant. Cholestasis, drug-induced liver injury, QT interval prolongation and renal impairment have notable signals in all Triazole antifungal drugs, with 50 percent of patients developing a severe clinical outcome. Isavuconazole had the lowest signal intensity and demonstrated a superior safety profile.

CONCLUSION

Most results are generally consistent with previous studies and are documented in the prescribing instructions, but some IMEs are not included, such as hepatitis fulminant. Additional pharmaco-epidemiological or experimental studies are required to validate the small number of unlabeled ADRs. TAD-related Important Medical Eventshave a considerable potential to cause clinically serious outcomes. Clinical use of Triazole antifungal drugs requires more attention.

Cyclodextrin-based delivery systems in parenteral formulations: a critical update review

Parenteral formulations are indispensable in clinical practice and often are the only option to administer drugs that cannot be administrated through other routes, such as proteins and certain anticancer drugs - which are indispensable to treat some of the most prevailing chronic diseases worldwide (like diabetes and cancer). Additionally, parenteral formulations play a relevant role in emergency care since they are the only ones that provide an immediate action of the drug after its administration. However, the development of parenteral formulations is a complex task owing to the specific quality and safety requirements set for these preparations and the intrinsic properties of the drugs. Amongst all the strategies that can be useful in the development of parenteral formulations, the formation of water-soluble host-guest inclusion complexes with cyclodextrins (CDs) has proven to be one of the most advantageous. CDs are multifunctional pharmaceutical excipients able to form water-soluble host-guest inclusion complexes with a wide variety of molecules, particularly drugs, and thus improve their apparent water-solubility, chemical stability, and bioavailability, to make them suitable for parenteral administration. Besides, CDs can be employed as building blocks of more complex injectable drug delivery systems with enhanced characteristics, such as nanoparticles and supramolecular hydrogels, that has been found particularly beneficial for the delivery of anticancer drugs. However, only a few CDs are considered safe when parenterally administered, and some of these types are already approved to be used in parenteral dosage forms. Therefore, the application of CDs in the development of parenteral formulations has been a more common practice in the last few years, due to their significant worldwide acceptance by the health authorities, promoting the development of safer and more efficient injectable drug delivery systems.

Safety and Tolerability of Remdesivir in Patients with End-stage Renal Disease on Maintenance Hemodialysis

Introduction

The use of remdesivir is not recommended in patients with end-stage renal disease (ESRD) with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection unless potential advantage offset disadvantage due to limited safety data. Our objective was to assess the safety of remdesivir in patients with end-stage renal failure and evaluate the outcome of this vulnerable group.

Methodology

We carried out a retrospective observational study in dialysis-dependent ESRD patients with SARS-CoV-2 infection who received a standard 5-day course of remdesivir (powder form) from June 2020 to December 2020. Oxygen requirement, hemogram, inflammatory markers, and liver function tests before and after remdesivir treatment were compared.

Result

We found thirty-nine such patients with mean age of patients 58.79 ± 12.13 years. Diabetes mellitus, hypertension, and cardiac diseases were present in 58.97, 87.17, and 23.07% of patients, respectively. Mean oxygen saturation on admission was 85.41% (±7.73). There were no events of hepatotoxicity, altered behavior, or infusion reaction. There was statistically significant improvement in total leukocyte count, absolute lymphocyte counts, and C-reactive protein (p value <0.001, 0.01, and 0.02, respectively) post remdesivir treatment. A total of 60% of patients had improved oxygenation while 13% of patients had no change in oxygen requirement after completion of remdesivir course. Mortality in our study was 28.21%. We did not find any significant benefit of early remdesivir administration (3-6 days of illness) on mortality or days of hospitalization.

Conclusion

The use of remdesivir in end-stage kidney disease is safe. Improvement in oxygenation was significant when baseline oxygen requirement was less. It requires prospective controlled trials with larger population to assess its impact on mortality.

How to cite this article

Shah MK, Parikh M, Prajapati D, Kute VB, Bhende P, Prajapati A, et al. Safety and Tolerability of Remdesivir in Patients with End-stage Renal Disease on Maintenance Hemodialysis. Indian J Crit Care Med 2022;26(5):619-625.

Pharmacokinetics, Pharmacodynamics, and Dose Optimization of Cefiderocol during Continuous Renal Replacement Therapy

BACKGROUND

The need for continuous renal replacement therapy (CRRT) in critically ill patients with serious infections is associated with clinical failure, emergence of resistance, and excess mortality. These poor outcomes are attributable in large part to subtherapeutic antimicrobial exposure and failure to achieve target pharmacokinetic/pharmacodynamic (PK/PD) thresholds during CRRT. Cefiderocol is a novel siderophore cephalosporin with broad in vitro activity against resistant pathogens and is often used to treat critically ill patients, including those receiving CRRT, despite the lack of data to guide dosing in this population.

OBJECTIVE

The aim of this study was to evaluate the PK and PD of cefiderocol during in vitro and in vivo CRRT and provide optimal dosing recommendations.

METHODS

The PK and dialytic clearance of cefiderocol was evaluated via an established in vitro CRRT model across various modes, filter types, and effluent flow rates. These data were combined with in vivo PK data from nine patients receiving cefiderocol while receiving CRRT from phase III clinical trials. Optimal dosing regimens and their respective probability of target attainment (PTA) were assessed via an established population PK model with Bayesian estimation and 1000-subject Monte Carlo simulations at each effluent flow rate.

RESULTS

The overall mean sieving/saturation coefficient during in vitro CRRT was 0.90 across all modes, filter types, effluent flow rates, and points of replacement fluid dilution tested. Adsorption was negligible at 10.9%. Three-way analysis of variance (ANOVA) and multiple linear regression analyses demonstrated that effluent flow rate is the primary driver of clearance during CRRT and can be used to calculate optimal cefiderocol doses required to match the systemic exposure observed in patients with normal renal function. Bayesian estimation of these effluent flow rate-based optimal doses in nine patients receiving CRRT from the phase III clinical trials of cefiderocol revealed comparable mean (± standard deviation) area under the concentration-time curve values as patients with normal renal function (1709 ± 539 mg·h/L vs. 1494 ± 58.4 mg·h/L; p = 0.26). Monte Carlo simulations confirmed these doses achieved >90% PTA against minimum inhibitory concentrations ≤4 mg/L at effluent flow rates from 0.5 to 5 L/h.

CONCLUSION

The optimal dosing regimens developed from this work have been incorporated into the prescribing information for cefiderocol, making it the first and only antimicrobial with labeled dosing for CRRT. Future clinical studies are warranted to confirm the efficacy and safety of these regimens.

The determination of Sulfobutylether β-Cyclodextrin Sodium (SBECD) by LC-MS/MS and its application in remdesivir pharmacokinetics study for pediatric patients

SBECD (Captisol®) with an average degree of substitution of 6.5 sulfobutylether functional groups (SBE = 6.5), is a solubility enhancer for remdesivir (RDV) and a major component in Veklury, which was approved by FDA for the treatment of patients with COVID-19 over 12 years old and weighing over 40 kg who require hospitalization. SBECD is cleared mainly by renal filtration, thus, potential accumulation of SBECD in the human body is a concern for patients dosed with Veklury with compromised renal function. An LC-MS/MS method was developed and validated for specific, accurate, and precise determination of SBECD concentrations in human plasma. In this method, the hexa-substituted species, SBE6, was selected for SBECD quantification, and the mass transition from its dicharged molecular ion [(M-2H)/2]^2-, Molecular (parent) Ion (Q1)/Molecular (parent) Ion (Q3) of m/z 974.7/974.7, was selected for quantitative analysis of SBECD. Captisol-G (SBE-γ-CD, SBE = 3) was chosen as the internal standard. With 25 µL of formic-acid-treated sample and with a calibration range of 10.0-1000 µg/mL, the method was validated with respect to pre-established criteria based on regulatory guidelines and was applied to determine SBECD levels in plasma samples collected from pediatric patients during RDV clinical studies.

Use of tocilizumab, remdesivir, and high-dose methylprednisolone prevents intubation in an ESRD patient with COVID-19 pneumonia

Coronavirus disease 2019 (COVID-19) has affected over 200 million patients worldwide. COVID-19 is transmitted through respiratory droplets from patient to patient or by touching a surface that has been contaminated by an infected patient. Many COVID-19 patients have other comorbidities, such as end-stage renal disease. Currently, management of COVID-19 in patients with end-stage renal disease is unclear. Some studies have shown improvement in this population with the use of tocilizumab, a humanized interleukin-6 monoclonal antibody, in addition to the standard therapy as per guidelines published by the National Institutes of Health. In this case report, we present a patient case where the use of remdesivir, tocilizumab, and pulse-dose methylprednisolone significantly improved symptoms and inflammatory biomarkers associated with COVID-19 in a patient with end-stage renal disease.

Efficacy of remdesivir for hospitalized COVID-19 patients with end stage renal disease

BACKGROUND

Since the beginning of corona virus disease 2019 (COVID-19) pandemic, there has been a widespread use of remdesivir in adults and children. There is little known information about its outcomes in patients with end stage renal disease who are on dialysis.

AIM

To assess the clinical outcomes with use of remdesivir in adult patients with end stage kidney failure on hemodialysis.

METHODS

A retrospective, multicenter study was conducted on patients with end stage renal disease on hemodialysis that were discharged after treatment for COVID-19 between April 1, 2020 and December 31, 2020. Primary endpoints were oxygen requirements, time to mortality and escalation of care needing mechanical ventilation.

RESULTS

A total of 45 patients were included in the study. Twenty patients received remdesivir, and 25 patients did not receive remdesivir. Most patients were caucasian, females with diabetes mellitus and hypertension being the commonest comorbidities. There was a trend towards reduced oxygen requirement (beta = -25.93, X² (1) = 6.65, P = 0.0099, probability of requiring mechanical ventilation (beta = -28.52, X² (1) = 22.98, P < 0.0001) and mortality (beta = -5.03, X² (1) = 7.41, P = 0.0065) in patients that received remdesivir compared to the control group.

CONCLUSION

Larger studies are justified to study the effects of remdesivir in this high-risk population with end stage kidney disease on dialysis.

Assessment of Safety of Remdesivir in Covid -19 Patients with Estimated Glomerular Filtration Rate (eGFR) < 30 ml/min per 1.73 m^2

PURPOSE

Safety of remdesivir in patients with renal impairment is unknown. Incidence of liver injury secondary to remdesivir is also unknown. The objective of this study is to assess the incidence of acute kidney injury (AKI) and to trend the liver enzymes during remdesivir treatment and change in eGFR from baseline to end of treatment as well as 48 h post completion of remdesivir therapy.

METHODS

This is a retrospective chart review study including adult patients admitted with COVID-19 receiving remdesivir with a baseline eGFR < 30 ml/min per 1.73 m^2 from December 2020 to May 2021. The primary outcome was to assess the incidence of AKI and hepatic injury. The secondary outcome was to assess the efficacy of remdesivir defined by change in oxygen requirement.

RESULTS

Seventy-one patients were included in the study. Patients experienced an improvement in eGFR from baseline (T0) to end of remdesivir treatment (T1), as well as 48 h after the end of the treatment (T2) ( + 30.3% and + 30.6% respectively, P < .0001). Creatinine reduced from baseline (T0) to T1 and T2 (-20.9% and -20.5% respectively, P < .0001). Creatinine clearance improved from baseline to T1 and T2 ( + 26.6% and + 26.2% respectively, p < .0001). Elevation of aminotransferase (AST) was observed at T1 ( + 2.5%, P  =  .727), however, AST reduction was seen at T2 (-15.8%, P  =  .021). Elevation in alanine transaminase (ALT) was observed at T1 and T2 ( + 25% and + 12%, P  =  .004 and P  =  .137 respectively). Both direct and total bilirubin remained stable and were not significantly changed from baseline.

CONCLUSION

Our study showed that remdesivir use in renally-impaired patients with eGFR < 30 ml/min is safe. Remdesivir may be considered as a therapeutic option in this population with COVID-19 infection.

Loading Pistacia atlantica essential oil in solid lipid nanoparticles and its effect on apoptosis of breast cancer cell line MDA-MB-231

Pistacia atlantica has an anti-cancer effect due to its essential oil which is the major constituent of P. atlantica. Unfortunately, this essential oil evaporates easily and make it less effective. The current research, therefore, aimed to improve the anti-cancer effect of P. atlantica essential oil (PAEO) in solid lipid nanoparticles (SLN). The chemical components of PAEO were assessed by gas chromatography. PAEO-SLNs were prepared by the probe-ultrasonication method, and their particle size, polydispersity index and zeta potential were determined. Encapsulation Efficiency (EE) and Loading Capacity (LC) of formulations was also calculated. Transmission electron microscopy was employed to determine the morphology of optimal formulation (PAEO-SLN4). Furthermore, the anticancer effects of PAEO-SLN4 against MDA-MB-231 cells were evaluated by cellular assays. The results showed that the type of surfactant and loading of the essential oil had a significant effect on size distribution, zeta potential and the polydispersity index. The encapsulation efficiency (EE%) and loading capacity for PAEO-SLN4 were 97.3% and 9.6%, respectively. The cellular assay demonstrates that PAEO-SLN4 could lead MDA-MB-231 cells to apoptosis. The findings also revealed that PAEO-SLN4 can stimulate apoptosis in MDA-MB-231 cells more than the placebo and free PAEO thereby indicating PAEO-SLN4 to be beneficial in breast cancer treatment.

Case Report: Severe SARS-CoV-2 Infection with Remdesivir in a Patient with ESRD

BACKGROUND

The novel coronavirus disease 2019 (COVID-19) has led to a global pandemic since its emergence from Wuhan, China, in December of 2019. As research continues to evolve, there is a paucity of reports describing the management and treatment of COVID-19 in patients with acute kidney failure and end-stage renal disease (ESRD). These patients have increased susceptibility to developing severe clinical symptoms from SARS-CoV-2 infection due to their underlying comorbidities. Remdesivir has emerged as a promising antiviral drug against SARS-CoV-2. However, data regarding the clinical benefits of remdesivir in patients with severe renal impairment is unavailable as they have been excluded from clinical trials due to the risk of sulfobutylether-β-cyclodextrin (SBECD) accumulation in patients with eGFR<30 ml/min per 1.73m2.

CASE PRESENTATION

We present the first case of a 47-year-old male with end-stage renal disease who was successfully treated with remdesivir during hospitalization for acute respiratory distress syndrome and respiratory failure arising from COVID-19. The worsening clinical progress of the patient despite intensive care and treatment with intravenous azithromycin therapy led to the decision to utilize remdesivir after a risk-benefit analysis, despite his eGFR being <15 ml/min per 1.73m2. Although the patient developed reversible hepatotoxicity, marked improvement of symptoms was observed after the five-day course of remdesivir was completed.

CONCLUSION

Our findings describe the first instance of compassionate use of remdesivir for the treatment of COVID-19 in the setting of end-stage renal disease, acute respiratory distress syndrome, and hypoxemic respiratory failure.

Correlation of antimicrobial fraction unbound and sieving coefficient in critically ill patients on continuous renal replacement therapy: a systematic review

Background

Fraction unbound has been used as a surrogate for antimicrobial sieving coefficient (SC) to predict extracorporeal clearance in critically ill patients on continuous renal replacement therapy (CRRT), but this is based largely on expert opinion.

Objectives

To examine relationships between package insert-derived fraction unbound (Fu-P), study-specific fraction unbound (Fu-S), and SC in critically ill patients receiving CRRT.

Methods

English-language studies containing patient-specific in vivo pharmacokinetic parameters for antimicrobials in critically ill patients requiring CRRT were included. The primary outcome included correlations between Fu-S, Fu-P, and SC. Secondary outcomes included correlations across protein binding quartiles, serum albumin, and predicted in-hospital mortality, and identification of predictors for SC through multivariable analysis.

Results

Eighty-nine studies including 32 antimicrobials were included for analysis. SC was moderately correlated to Fu-S (R2 = 0.55, P &lt; 0.001) and Fu-P (R2 = 0.41, P &lt; 0.001). SC was best correlated to Fu-S in first (&lt;69%) and fourth (&gt;92%) quartiles of fraction unbound and above median albumin concentrations of 24.5 g/L (R2 = 0.71, P = 0.07). Conversely, correlation was weaker in patients with mortality estimates greater than the median of 55% (R2 = 0.06, P = 0.84). SC and Fu-P were also best correlated in the first quartile of antimicrobial fraction unbound (R2 = 0.66, P &lt; 0.001). Increasing Fu-P, flow rate, membrane surface area, and serum albumin, and decreasing physiologic charge significantly predicted increasing SC.

Conclusions

Fu-S and Fu-P were both reasonably correlated to SC. Caution should be taken when using Fu-S to calculate extracorporeal clearance in antimicrobials with 69%–92% fraction unbound or with &gt;55% estimated in-hospital patient mortality. Fu-P may serve as a rudimentary surrogate for SC when Fu-S is unavailable.

Voriconazole Pharmacokinetics Are Not Altered in Critically Ill Patients with Acute-on-Chronic Liver Failure and Continuous Renal Replacement Therapy: An Observational Study

Infection and sepsis are a main cause of acute-on-chronic liver failure (ACLF). Besides bacteria, molds play a role. Voriconazole (VRC) is recommended but its pharmacokinetics (PK) may be altered by ACLF. Because ACLF patients often suffer from concomitant acute renal failure, we studied the PK of VRC in patients receiving continuous renal replacement therapy (RRT) with ACLF and compared it to PK of VRC in critically ill patients with RRT without concomitant liver failure (NLF). In this prospective cohort study, patients received weight-based VRC. Pre- and post-dialysis membrane, and dialysate samples obtained at different time points were analyzed by high-performance liquid chromatography. An integrated dialysis pharmacometric model was used to model the available PK data. The recommended, 50% lower, and 50% higher doses were analyzed by Monte-Carlo simulation (MCS) for day 1 and at steady-state with a target trough concentration (TC) of 0.5–3mg/L. Fifteen patients were included in this study. Of these, 6 patients suffered from ACLF. A two-compartment model with linear clearance described VRC PK. No difference for central (V1) or peripheral (V2) volumes of distribution or clearance could be demonstrated between the groups. V1 was 80.6L (95% confidence interval: 62.6–104) and V2 106L (65–166) with a body clearance of 4.7L/h (2.87–7.81) and RRT clearance of 1.46L/h (1.29–1.64). MCS showed TC below/within/above target of 10/74/16% on day 1 and 9/39/52% at steady-state for the recommended dose. A 50% lower dose resulted in 26/72/1% (day 1) and 17/64/19% at steady-state and 7/57/37% and 7/27/67% for a 50% higher dose. VRC pharmacokinetics are not significantly influenced by ACLF in critically ill patients who receive RRT. Maintenance dose should be adjusted in both groups. Due to the high interindividual variability, therapeutic drug monitoring seems inevitable.

Acute Kidney Injury and Acute Respiratory Distress Syndrome

Acute kidney injury (AKI) complicates approximately a third of all acute respiratory distress syndrome (ARDS) cases, and the combination of the two drastically worsens prognosis. Recent advances in ARDS supportive care have led to improved outcomes; however, much less is known on how to prevent and support patients with AKI and ARDS together. Understanding the dynamic relationship between the kidneys and lungs is crucial for the practicing intensivist to prevent injury. This article summarizes key concepts for the critical care physician managing a patient with ARDS complicated by AKI. Also provided is a discussion of AKI in the COVID-19 era.

A quantitative HPLC method for simultaneous determination of prodrug of voriconazole and voriconazole in beagle plasma, and its application to a toxicokinetic study

A simple, rapid, efficient and reproducible method based on High Performance Liquid Chromatography (HPLC) for simultaneous determination of prodrug of voriconazole (POV) and voriconazole in beagle plasma has been established and validated. Omeprazole was utilized as the sole internal standard. Analytes and internal standards were extracted through protein precipitation and separated on a Venusil XBP C18 chromatography column (4.6 × 250 mm, 5 µm). The mobile phase was methanol and 20 mmol/L potassium dihydrogen phosphate. Chromatographic separation was achieved by using an isocratic elution procedure that used 65% methanol and a flow rate of 1 mL/min. The ultraviolet (UV) detection wavelength was 256 nm and the total running time was 15 min. This method showed good linear ranges of 100–75,000 ng/mL for voriconazole prodrug and 200–100,000 ng/mL for voriconazole respectively. The precision and accuracy were acceptable. Analytes in plasma samples are stable under different temperatures and storage conditions. The developed HPLC method has been successfully applied to the studies of toxicokinetics of POV after intravenous drip in beagle and provided important information for the further development and application.

Influenza-Associated Disseminated Aspergillosis in a 9-Year-Old Girl Requiring ECMO Support

A previously healthy 9-year-old girl developed fulminant myocarditis due to severe influenza A infection complicated with methicillin-resistant Staphylococcus aureus pneumonia, requiring extracorporeal membrane oxygenation (ECMO) support. Twelve days after admission, Aspergillus fumigatus was isolated in tracheal aspirate, and 12 h later she suddenly developed anisocoria. Computed tomography (CT) of the head showed fungal brain lesions. Urgent decompressive craniectomy with lesion drainage was performed; histopathology found hyphae in surgical samples, culture-positive for Aspergillus fumigatus (susceptible to azoles, echinocandins, and amphotericin B). Extension workup showed disseminated aspergillosis. After multiple surgeries and combined antifungal therapy (isavuconazole plus liposomal amphotericin B), her clinical course was favorable. Isavuconazole therapeutic drug monitoring was performed weekly. Extensive immunological study ruled out primary immunodeficiencies. Fluorine-18 fluorodeoxyglucose positron emission tomography/CT (¹⁸F-FDG PET/CT) follow-up showed a gradual decrease in fungal lesions. Influenza-associated pulmonary aspergillosis is well-recognized in critically ill adult patients, but pediatric data are scant. Clinical features described in adults concur with those of our case. Isavuconazole, an off-label drug in children, was chosen because our patient had severe renal failure. To conclude, influenza-associated pulmonary aspergillosis is uncommon in children admitted to intensive care for severe influenza, but pediatricians should be highly aware of this condition to enable prompt diagnosis and treatment.

A case series of non-valvular cardiac aspergillosis in critically ill solid organ transplant and non-transplant patients and systematic review

INTRODUCTION

Non-valvular cardiac aspergillosis is a rare infection of the pericardium, myocardium or endocardium and is associated with a high mortality. There is a paucity of reports of non-valvular cardiac aspergillosis in critically ill and solid organ transplant (SOT) patients. The majority of cases have been reported in haemato-oncology patients, some of whom have undergone a bone marrow transplant.

OBJECTIVES

We describe four cases affected by non-valvular cardiac aspergillosis in the intensive care setting including a systematic review of this extremely rare infection which is associated with high mortality.

RESULTS

All four-patients died but presented with varying clinical, radiological and microbiological evidence of the disease. Three patients presented following complications after solid organ transplantation, two in the context of acute liver failure and emergency liver transplant and one several years after a double lung transplant. The last patient presented with necrotising gall stone pancreatitis, multi-organ failure and subsequently a prolonged intensive care unit (ICU) stay. On review of the literature, January 1955 to July 2019, 45 cases were identified, with different risk factors, clinical and radiological manifestations, treatment regimen and outcome.

CONCLUSION

Antemortem diagnosis of cardiac aspergillosis is difficult and rare, with no cases reporting positive blood culture results. Galactomannan serology has poor sensitivity in solid organ transplant patients, further reduced by prophylactic antimicrobial treatment, which is common in the ICU setting especially post-transplant patients. Due to the scarcity of cases, treatment is extrapolated from invasive aspergillosis management, with emphasis on early treatment with combination therapy.

ADME and Pharmacokinetic Properties of Remdesivir: Its Drug Interaction Potential

On 11 March 2020, the World Health Organization (WHO) classified the Coronavirus Disease 2019 (COVID-19) as a global pandemic, which tested healthcare systems, administrations, and treatment ingenuity across the world. COVID-19 is caused by the novel beta coronavirus Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Since the inception of the pandemic, treatment options have been either limited or ineffective. Remdesivir, a drug originally designed to be used for Ebola virus, has antiviral activity against SARS-CoV-2 and has been included in the COVID-19 treatment regimens. Remdesivir is an adenosine nucleotide analog prodrug that is metabolically activated to a nucleoside triphosphate metabolite (GS-443902). The active nucleoside triphosphate metabolite is incorporated into the SARS-CoV-2 RNA viral chains, preventing its replication. The lack of reported drug development and characterization studies with remdesivir in public domain has created a void where information on the absorption, distribution, metabolism, elimination (ADME) properties, pharmacokinetics (PK), or drug-drug interaction (DDI) is limited. By understanding these properties, clinicians can prevent subtherapeutic and supratherapeutic levels of remdesivir and thus avoid further complications in COVID-19 patients. Remdesivir is metabolized by both cytochrome P450 (CYP) and non-CYP enzymes such as carboxylesterases. In this narrative review, we have evaluated the currently available ADME, PK, and DDI information about remdesivir and have discussed the potential of DDIs between remdesivir and different COVID-19 drug regimens and agents used for comorbidities. Considering the nascent status of remdesivir in the therapeutic domain, extensive future work is needed to formulate safer COVID-19 treatment guidelines involving this medication.

Taskforce report on the diagnosis and clinical management of COVID-19 associated pulmonary aspergillosis

Purpose

Invasive pulmonary aspergillosis (IPA) is increasingly reported in patients with severe coronavirus disease 2019 (COVID-19) admitted to the intensive care unit (ICU). Diagnosis and management of COVID-19 associated pulmonary aspergillosis (CAPA) are challenging and our aim was to develop practical guidance.

Methods

A group of 28 international experts reviewed current insights in the epidemiology, diagnosis and management of CAPA and developed recommendations using GRADE methodology.

Results

The prevalence of CAPA varied between 0 and 33%, which may be partly due to variable case definitions, but likely represents true variation. Bronchoscopy and bronchoalveolar lavage (BAL) remain the cornerstone of CAPA diagnosis, allowing for diagnosis of invasive Aspergillus tracheobronchitis and collection of the best validated specimen for Aspergillus diagnostics. Most patients diagnosed with CAPA lack traditional host factors, but pre-existing structural lung disease and immunomodulating therapy may predispose to CAPA risk. Computed tomography seems to be of limited value to rule CAPA in or out, and serum biomarkers are negative in 85% of patients. As the mortality of CAPA is around 50%, antifungal therapy is recommended for BAL positive patients, but the decision to treat depends on the patients’ clinical condition and the institutional incidence of CAPA. We recommend against routinely stopping concomitant corticosteroid or IL-6 blocking therapy in CAPA patients.

Conclusion

CAPA is a complex disease involving a continuum of respiratory colonization, tissue invasion and angioinvasive disease. Knowledge gaps including true epidemiology, optimal diagnostic work-up, management strategies and role of host-directed therapy require further study.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00134-021-06449-4.

Remdesivir, Renal Function and Short-Term Clinical Outcomes in Elderly COVID-19 Pneumonia Patients: A Single-Centre Study

BACKGROUND

Remdesivir, an antiviral agent able to reduce inflammatory cascade accompanying severe, life-threatening pneumonia, became the first drug approved by the Food and Drug Administration for the treatment of hospitalized patients with coronavirus 2 related severe acute respiratory syndrome (SARS CoV2). As from its previously known clinical indications, the use of remdesivir in the presence of severe renal impairment is contraindicated; however, the impact of remdesivir on renal function in aging patients has not been elucidated.

SUBJECTS AND METHODS

This retrospective observational study involved 109 individuals consecutively admitted in internal medicine section, Azienda Ospedaliero Universitaria Pisana hospital, in November-December 2020 due to a confirmed diagnosis of SARS CoV2 and receiving remdesivir according to international inclusion criteria. Biochemical variables at admission were evaluated, together with slopes of estimated glomerular filtration rate (eGFR) built during remdesivir treatment. Participants were followed until discharge or exitus.

RESULTS

Patients were stratified according to age (80 formed the study cohort and 29 served as controls); CKD stage III was present in 46% of them. No patients showed any sign of deteriorated renal function during remdesivir. Fourteen patients in the elderly cohort deceased; their eGFR at baseline was significantly lower. Recovered patients were characterized by a relevant eGFR gaining during remdesivir treatment.

CONCLUSION

We show here for the first time as remdesivir does not influence eGFR in a cohort of elderly people hospitalized for SARS CoV2, and that eGFR gain during such treatment is coupled with a better prognosis.

Antifungals in Clinical Use and the Pipeline

Over the past 15 years, there has been an increase in the development and utilization of newer antifungal agents. The ideal antifungal, however, in regard to spectrum of activity, pharmacokinetic/pharmacodynamic properties, development of resistance, safety, and drug interaction profile remains elusive. This article reviews pharmacologic aspects of Food and Drug Administration-approved polyenes, flucytosine, azoles, and echinocandins as well as promising pipeline antifungal agents. Unique properties of these newer agents are highlighted. The clinical role of established and investigational antifungal agents as treatment and/or prevention of invasive fungal infections is discussed.

Therapeutic dilemmas in dialysis patients hospitalized for COVID-19: balancing between nihilism, off-label treatment and side effects

Avoiding the use of drugs in patients with a glomerular filtration rate (GFR) <30 mL/min/1.73 m2 is due to the exclusion of this group of patients from many clinical trials. However, in view of the widespread COVID-19 pandemic and the need to treat all patients, including those with renal failure, the World Health Organization points out in the Solidarity trial the need for the inclusion some patients with kidney failure and recognizes the urgent need for trials/studies in patients with coronavirus disease 2019 (COVID-19) with lower GFR. It is well known that the therapeutic goal to treat patients with renal failure, acute kidney injury or on maintenance dialysis is complicated by pharmacokinetics, drug interactions and extracorporeal therapies. In patients with COVID-19 and impaired kidney function, the role of nephrologists is crucial in order to draw a balance between nihilism and benefits or potentially harmful effects of current available treatments. The potential use of European Medicines Agency recommended remdesivir and dexamethasone for COVID-19 among dialysis patients are discussed.

Liver and kidney function in patients with Covid-19 treated with remdesivir

For the treatment of Covid‐19 patients with remdesivir, poor renal and liver function were both exclusion criteria in randomized clinical trials and contraindication for treatment. Also, nephrotoxicity and hepatotoxicity are reported as adverse events. We retrospectively reviewed renal and liver functions of Covid‐19 103 patients who received remdesivir in the 15 days after treatment initiation. Approximately 20% of the patient population met randomized clinical trial exclusion criteria. In total, 11% of the patients had a decrease in estimated glomerular filtration rate >10 mL/min/1.73m². Also, 25 and 35% had increased alanine transaminase and aspartate transaminase levels, respectively. However, serious adverse events were limited. Therefore, based on these preliminary results, contraindications based on kidney and liver function should not be absolute for remdesivir treatment in patients with Covid‐19 if these functions are monitored regularly. A larger patient cohort is warranted to confirm our results.

Pharmacokinetics and dialytic clearance of apixaban during in vitro continuous renal replacement therapy

Background

To evaluate the transmembrane clearance (CL_TM) of apixaban during modeled in vitro continuous renal replacement therapy (CRRT), assess protein binding and circuit adsorption, and provide initial dosing recommendations.

Methods

Apixaban was added to the CRRT circuit and serial pre-filter bovine blood samples were collected along with post-filter blood and effluent samples. All experiments were performed in duplicate using continuous veno-venous hemofiltration (CVVH) and hemodialysis (CVVHD) modes, with varying filter types, flow rates, and point of CVVH replacement fluid dilution. Concentrations of apixaban and urea were quantified via liquid chromatography-tandem mass spectrometry. Plasma pharmacokinetic parameters for apixaban were estimated via noncompartmental analysis. CL_TM was calculated via the estimated area under the curve (AUC) and by the product of the sieving/saturation coefficient (SC/SA) and flow rate. Two and three-way analysis of variance (ANOVA) models were built to assess the effects of mode, filter type, flow rate, and point of dilution on CL_TM by each method. Optimal doses were suggested by matching the AUC observed in vitro to the systemic exposure demonstrated in Phase 2/3 studies of apixaban. Linear regression was utilized to provide dosing estimations for flow rates from 0.5–5 L/h.

Results

Mean adsorption to the HF1400 and M150 filters differed significantly at 38 and 13%, respectively, while mean (± standard deviation, SD) percent protein binding was 70.81 ± 0.01%. Effect of CVVH point of dilution did not differ across filter types, although CL_TM was consistently significantly higher during CRRT with the HF1400 filter compared to the M150. The three-way ANOVA demonstrated improved fit when CL_TM values calculated by AUC were used (adjusted R² 0.87 vs. 0.52), and therefore, these values were used to generate optimal dosing recommendations. Linear regression revealed significant effects of filter type and flow rate on CL_TM by AUC, suggesting doses of 2.5–7.5 mg twice daily (BID) may be needed for flow rates ranging from 0.5–5 L/h, respectively.

Conclusion

For CRRT flow rates most commonly employed in clinical practice, the standard labeled 5 mg BID dose of apixaban is predicted to achieve target systemic exposure thresholds. The safety and efficacy of these proposed dosing regimens warrants further investigation in clinical studies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02248-7.

Computational and theoretical exploration for clinical suitability of Remdesivir drug to SARS-CoV-2

A methodology for the exploration of clinical suitability of Remdesivir drug to SARS-CoV-2 main protease based on the computational, theoretical analysis pertinent to Gibb's free energy computed from the Molecular Dynamic simulations with OPLS-AA force field at 300 K/atmospheric pressure and the variation of thermodynamic potentials over the entire simulation run of 100 ns. This study emphasized the suitability of Remdesivir drug to SARS-CoV-2 protein and the same is emphasized by the results of global clinical trials. This methodology can be applied for future design, development of more specific repurposed inhibitors for the treatment of SARS-CoV-2 infection.

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.

New Perspectives on Antimicrobial Agents: Remdesivir Treatment for COVID-19

Remdesivir was recently approved by the Food and Drug Administration for the treatment of hospitalized patients with coronavirus disease 2019 (COVID-19). Remdesivir is the prodrug of an adenosine analogue that inhibits viral replication of several RNA virus families, including Coronaviridae. Preclinical data in animal models of coronavirus diseases, including COVID-19, have demonstrated that early treatment with remdesivir leads to improved survival, decreased lung injury, and decreased levels of viral RNA.

Remdesivir was recently approved by the Food and Drug Administration for the treatment of hospitalized patients with coronavirus disease 2019 (COVID-19). Remdesivir is the prodrug of an adenosine analogue that inhibits viral replication of several RNA virus families, including Coronaviridae. Preclinical data in animal models of coronavirus diseases, including COVID-19, have demonstrated that early treatment with remdesivir leads to improved survival, decreased lung injury, and decreased levels of viral RNA. Recent clinical data have demonstrated the clinical activity of remdesivir in terms of faster time to recovery in patients with severe COVID-19 and higher odds of improved clinical status in patients with moderate COVID-19. Here, clinical trials published to date are presented and appraised. Remdesivir’s potential benefits and its favorable adverse-event profile make it an option for the treatment of COVID-19. This article examines the available literature describing remdesivir’s pharmacology, pharmacokinetics, and preclinical and clinical data.

Remdesivir Use in the Setting of Severe Renal Impairment: A Theoretical Concern or Real Risk?

INTRODUCTION

Remdesivir (RDV) is FDA approved for COVID-19, but not recommended for patients with severe renal impairment (SRI, i.e. creatinine clearance < 30ml/min). Few studies have evaluated RDV in patients with SRI due to theoretical toxicity concerns.

METHODS

Hospitalized patients receiving RDV for COVID-19 between 5/1/2020-10/31/2020 were analyzed in a retrospective chart review. We compared incident adverse events (AEs) following RDV in patients with and without SRI, including hepatotoxicity, nephrotoxicity, any reported AE, mortality and length of stay.

RESULTS

A total of 135 patients received RDV, 20 patients had SRI. Patients with SRI were significantly older (70 vs. 54 years, p=0.0001). The incidence of possible AEs following RDV was 20% among those with SRI versus 11% without (p=0.26). LFT elevations occurred in 10% vs. 4% (p=0.28), and SCr elevations occurred in 20% vs. 6% (p=0.06) of patients with SRI versus those without, respectively. The LFT and SCr elevations were not attributed to RDV in either group. Mortality and length of stay were comparable and consistent with historical controls.

CONCLUSION

RDV AEs occurred infrequently with low severity and were not significantly different between those with and without SRI. While a higher percentage of patients with SRI experienced SCr elevations, 3 (75%) patients were in AKI prior to RDV. Overall, the use of RDV in this small series of patients with SRI appeared to be relatively safe, and the potential benefit outweighed the theoretical risk of liver or renal toxicity; however, additional studies are needed to confirm this finding.

That Escalated Quickly: Remdesivir's Place in Therapy for COVID-19

Remdesivir is a nucleoside antiviral recently studied in several randomized trials for treatment of COVID-19. The available observational and prospective data are conflicting, requiring clinicians to critically evaluate and reconcile results to determine patient populations that may optimally benefit from remdesivir therapy, especially while drug supply is scarce. In this review, we analyze pertinent clinical remdesivir data for patients with COVID-19 from January 1, 2020, through May 31, 2020.

Voriconazole therapeutic drug monitoring in critically ill patients improves efficacy and safety of antifungal therapy

Since voriconazole plasma trough concentration (VPC) is related to its efficacy and adverse events, therapeutic drug monitoring (TDM) is recommended to perform. However, there is no report about the data of voriconazole TDM in critically ill patients in China. This retrospective study was performed to determine whether voriconazole TDM was associated with treatment response and/or voriconazole adverse events in critically ill patients, and to identify the potential risk factors associated with VPC. A total of 216 critically ill patients were included. Patients were divided into two groups: those underwent voriconazole TDM (TDM group, n = 125) or did not undergo TDM (non-TDM group, n = 91). The clinical response and adverse events were recorded and compared. Furthermore, in TDM group, multivariate logistic regression analysis was performed to identify the possible risk factors resulting in the variability in initial VPC. The complete response in the TDM group was significantly higher than that in the non-TDM group (P = .012). The incidence of adverse events strongly associated with voriconazole in the non-TDM group was significantly higher than that in the TDM group (19.8% vs 9.6%; P = .033). The factors, including age (OR 0.934, 95% CI: 0.906-0.964), male (OR 5.929, 95% CI: 1.524-23.062), serum albumin level (OR 1.122, 95% CI: 1.020-1.234), diarrhoea (OR 4.953, 95% CI: 1.495-16.411) and non-intravenous administration (OR 4.763, 95% CI: 1.576-14.39), exerted the greatest effects on subtherapeutic VPC (VPC < 1.5 mg/L) in multivariate analysis. Intravenous administration (OR 7.657, 95% CI: 1.957-29.968) was a significant predictor of supratherapeutic VPC (VPC > 4.0 mg/L). TDM can result in a favourable clinical efficacy and a lower incidence of adverse events strongly associated with voriconazole in critically ill patients. Subtherapeutic VPC was closely related to younger age, male, hyperalbuminaemia, diarrhoea and non-intravenous administration, and intravenous administration was a significant predictor of supratherapeutic VPC.

Remdesivir: Review of Pharmacology, Pre-clinical Data, and Emerging Clinical Experience for COVID-19

The global pandemic of novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has created an urgent need for effective antivirals. Remdesivir (formerly GS-5734) is a nucleoside analogue pro-drug currently being evaluated in COVID-19 clinical trials. Its unique structural features allow high concentrations of the active triphosphate metabolite to be delivered intracellularly and it evades proofreading to successfully inhibit viral RNA synthesis. In pre-clinical models, remdesivir has demonstrated potent antiviral activity against diverse human and zoonotic β-coronaviruses, including SARS-CoV-2. In this article, we critically review available data on remdesivir with an emphasis on biochemistry, pharmacology, pharmacokinetics, and in vitro activity against coronaviruses as well as clinical experience and current progress in COVID-19 clinical trials.

Recommendation of Antimicrobial Dosing Optimization During Continuous Renal Replacement Therapy

Continuous Renal Replacement Therapy (CRRT) is more and more widely used in patients for various indications recent years. It is still intricate for clinicians to decide a suitable empiric antimicrobial dosing for patients receiving CRRT. Inappropriate doses of antimicrobial agents may lead to treatment failure or drug resistance of pathogens. CRRT factors, patient individual conditions and drug pharmacokinetics/pharmacodynamics are the main elements effecting the antimicrobial dosing adjustment. With the development of CRRT techniques, some antimicrobial dosing recommendations in earlier studies were no longer appropriate for clinical use now. Here, we reviewed the literatures involving in new progresses of antimicrobial dosages, and complied the updated empirical dosing strategies based on CRRT modalities and effluent flow rates. The following antimicrobial agents were included for review: flucloxacillin, piperacillin/tazobactam, ceftriaxone, ceftazidime/avibactam, cefepime, ceftolozane/tazobactam, sulbactam, meropenem, imipenem, panipenem, biapenem, ertapenem, doripenem, amikacin, ciprofloxacin, levofloxacin, moxifloxacin, clindamycin, azithromycin, tigecycline, polymyxin B, colistin, vancomycin, teicoplanin, linezolid, daptomycin, sulfamethoxazole/trimethoprim, fluconazole, voriconazole, posaconzole, caspofungin, micafungin, amphotericin B, acyclovir, ganciclovir, oseltamivir, and peramivir.

Extrapolating Antifungal Animal Data to Humans - Is it reliable?

PURPOSE OF REVIEW

This article aimed to review animal models of antifungals and identifies human literature to assess if the extrapolation of results is reliable.

RECENT FINDINGS

Animal studies have helped identify AUC/MIC targets for new drugs and formulations such as isavuconazole and delayed release posaconazole that have translated to successful outcomes in humans. Models have also been influential in the identification of possible combination therapies for the treatment of aspergillosis, such as voriconazole and echinocandins. However, challenges are endured with animal models when it comes to replicating the pharmacokinetics of humans which has been exemplified with the newest itraconazole formulation. Additionally, animal models have displayed a survival benefit with the use of iron chelators and amphotericin for mucormycosis which was not demonstrated in humans.

SUMMARY

Animal models have been a staple in the development and optimization of antifungal agents. They afford the ability to investigate uncommon diseases, such as invasive fungal infections, that would otherwise take years and many resources to complete. Although there are many benefits of animal models there are also shortcomings. This is why the reliability of extrapolating data from animal models to humans is often scrutinized.

Pharmacokinetics and Pharmacodynamics of Anti-infective Agents during Continuous Veno-venous Hemofiltration in Critically Ill Patients: Lessons Learned from an Ancillary Study of the IVOIRE Trial

Background

Hemofiltration rate, changes in blood and ultrafiltration flow, and discrepancies between the prescribed and administered doses strongly influence pharmacokinetics (PK) and pharmacodynamics (PD) of antimicrobial agents during continuous veno-venous hemofiltration (CVVH) in critically ill patients.

Methods

Ancillary data were from the prospective multicenter IVOIRE (hIgh VOlume in Intensive caRE) study. High volume (HV, 70 mL/kg/h) was at random compared with standard volume (SV, 35 mL/kg/h) CVVH in septic shock patients with acute kidney injury (AKI). PK/PD parameters for all antimicrobial agents used in each patient were studied during five days.

Results

Antimicrobial treatment met efficacy targets for both percentage of time above the minimal inhibitory concentration and inhibitory quotient. A significant correlation was observed between the ultrafiltration flow and total systemic clearance (Spearman test: P < 0.005) and between CVVH clearance and drug elimination half-life (Spearman test: P < 0.005). All agents were easily filtered. Mean sieving coefficient ranged from 38.7% to 96.7%. Mean elimination half-life of all agents was significantly shorter during HV-CVVH (from 1.29 to 28.54 h) than during SV-CVVH (from 1.51 to 33.85 h) (P < 0.05).

Conclusions

This study confirms that CVVH influences the PK/PD behavior of most antimicrobial agents. Antimicrobial elimination was directly correlated with convection rate. Current antimicrobial dose recommendations will expose patients to underdosing and increase the risk for treatment failure and development of resistance. Dose recommendations are proposed for some major antibiotic and antifungal treatments in patients receiving at least 25 mL/kg/h CVVH.

Acute Pulmonary Aspergillosis as a Severe Complication of Influenza, Pneumococcal Pneumonia, and Staphylococcus aureus Bacteremia in ICU

Background. Acute aspergillosis is a disease with dramatic progression and high mortality if not treated rapidly. However, diagnosing and treating is challenging, as the risk factors are not fully understood. Case Presentation. A fifty-three-year-old woman without any comorbidities was admitted to hospital due to high fever. Infections with influenza and pneumonia and Staphylococcus aureus bacteremia were diagnosed. The patient improved at first due to antimicrobial therapy; nine days after admission, her clinical condition deteriorated again, and she was transferred to ICU due to septic shock accompanied by respiratory failure, necessitating mechanical ventilation and high-dose catecholamine support. A CT scan showed a resolving inflammatory infiltrate bilateral caverns with markedly thickened walls. A culture from a bronchoalveolar lavage grew Aspergillus fumigatus. Galactomannan testing was positive in a bronchoalveolar lavage sample, and beta-D-glucan was positive in serum. Antifungal therapy with voriconazole and intermittent isavuconazole due to renal failure was performed, followed by a surgical resection of the caverns. Patient’s recovery was complicated by several severe bleeding episodes in the lungs. However, the patient showed full recovery and was discharged after 109 days in hospital. Conclusions. This case report highlights multiple complications of influenza and the difficulties of diagnosing and treating acute pulmonary aspergillosis. Furthermore, it stresses the importance for further studies to deepen the understanding about the association between influenza and aspergillosis and to shed further light on adequate therapy.

Brexanolone (Zulresso): Finally, an FDA-Approved Treatment for Postpartum Depression

Objective: To review the safety and efficacy of brexanolone for the treatment of moderate to severe postpartum depression (PPD). Data Sources: A literature search through PubMed was conducted (January 2012 to July 2019) using the keyword brexanolone for clinical trials published in the English language. Study Selection and Data Extraction: Articles were selected if they were related to the Food and Drug Administration (FDA) approval of brexanolone or provided novel clinical information regarding this drug entity. Data Synthesis: The findings of the review show that brexanolone administered via IV infusion is both an effective and a fairly safe option for the treatment of PPD. Relevance to Patient Care and Clinical Practice: There are several antidepressants currently used to treat PPD; however, this is the first with FDA approval for this indication. The rapid onset of action of brexanolone may offer a quicker relief of these symptoms and may possibly lead to improved quality of life for both the mother and the child. Conclusion and Relevance: The recent FDA approval of brexanolone may offer an effective treatment of moderate to severe PPD and has been shown to rapidly decrease depression symptoms.