Isavuconazole: A New Broad-Spectrum Triazole Antifungal Agent

Structural modification strategies of triazoles in anticancer drug development

The triazole functional group plays a pivotal role in the composition of biomolecules with potent anticancer activities, including numerous clinically approved drugs. The strategic utilization of the triazole fragment in the rational modification of lead compounds has demonstrated its ability to improve anticancer activities, enhance selectivity, optimize pharmacokinetic properties, and overcome resistance. There has been significant interest in triazole-containing hybrids in recent years due to their remarkable anticancer potential. However, previous reviews on triazoles in cancer treatment have failed to provide tailored design strategies specific to these compounds. Herein, we present an overview of design strategies encompassing a structure-modification approach for incorporating triazoles into hybrid molecules. This review offers valuable references and briefly introduces the synthesis of triazole derivatives, thereby paving the way for further research and advancements in the field of effective and targeted anticancer therapies.

Effectiveness of isavuconazole in invasive cerebral aspergillosis during hematopoietic stem cell transplantation in a pediatric patient with myelodysplastic syndrome: A case report

Pediatric myelodysplasia syndrome is often characterized by hypoplastic bone marrow morphology and predisposition to infection. Invasive aspergillosis during hematopoietic stem cell transplantation poses a significant threat and often requires voriconazole (VRCZ) therapy. However, difficulties in achieving appropriate VRCZ blood levels due to drug interactions have prompted the exploration of alternative treatments, such as isavuconazole (ISCZ). We present the case of a 4-year-old boy with myelodysplasia syndrome who developed multiple abscesses, including a brain abscess caused by Aspergillus fumigatus, and was successfully treated with ISCZ. Despite initial treatment with liposomal amphotericin B and VRCZ, the patient's condition deteriorated. Transitioning to ISCZ treatment resulted in significant clinical improvement, resolution of the abscesses, and reduced antigen levels. Although ISCZ induced hepatic enzyme elevation, supportive care improved without discontinuation of treatment. This case highlights the potential of ISCZ in cases of pediatric invasive aspergillosis where traditional therapies fail, underscoring the need for further research and formulation development to optimize its use in this population. As more cases accumulate, ISCZ may become a promising option for treating severe invasive aspergillosis in pediatric patients undergoing hematopoietic stem cell transplantation.

Pharmacokinetics of isavuconazonium sulfate and its active metabolite isavuconazole in healthy dogs

Invasive fungal infections (IFIs) are growing in importance in veterinary and human medicine. IFIs such as aspergillosis, blastomycosis, coccidioidomycosis and histoplasmosis remain challenging to treat in dogs. Isavuconazole is a novel antifungal medication that, when compared to currently used azoles, has an expanded spectrum of antifungal activity Rudramurthy (2011), Pfaller (2013), Spec (2018), has more predictable pharmacokinetics in humans Desai (2016), Cojutti (2021) and may cause fewer side effects such as liver and renal toxicity Maertens (2016), DiPippo (2018). The pharmacokinetic profile and safety of isavuconazole in dogs has not yet been characterized. The purpose of this study was to evaluate the pharmacokinetics of isavuconazole in healthy dogs that received a single dose of the prodrug isavuconazonium sulfate. Using full crossover design, six healthy beagle dogs received isavuconazonium sulfate at a mean (+/- SD) dose of 20.6 (+/- 2.8) mg/kg orally and 21.8 (+/- 4.2) mg/kg intravenously. Plasma was collected for batched pharmacokinetic analysis of prodrug and metabolite, isavuconazole, by ultra-high-pressure liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). The median (Q1-Q3) maximum isavuconazole peak plasma concentration was estimated at 3,876.5 (2,811.0-4,800.0) ng/mL following oral administration, with a median (Q1-Q3) peak level at 1.3 (1.0-2.0) hours. Following intravenous administration, the median (Q1-Q3) isavuconazole peak plasma concentration was estimated at 3,221.5 (2,241.5-3,609.0) ng/mL, with a median (Q1-Q3) peak level at 0.4 (0.3-0.6) hours. The median (Q1-Q3) half-life of isavuconazole was 9.4 (7.0-12.2) hours and 14.0 (8.1-21.7) hours for oral and intravenous routes, respectively. One dog received inadvertent subcutaneous drug administration without any apparent adverse effects. Another dog experienced an anaphylactic reaction following accidental rapid drug infusion. No other drug-related adverse events were observed. At dosages used in this study, healthy dogs achieved isavuconazole plasma levels comparable to human therapeutic targets, and when properly administered the drug was well-tolerated.

Clinical Pharmacokinetics and Pharmacodynamics of Letermovir in Allogenic Hematopoietic Cell Transplantation

Letermovir is a newly developed antiviral agent used for the prophylaxis of human cytomegalovirus infections in patients undergoing allogeneic hematopoietic cell transplantation. This novel anti-cytomegalovirus drug, used for the prophylaxis of cytomegalovirus reactivation until approximately 200 days after transplantation, effectively reduces the risk of clinically significant cytomegalovirus infection. No human counterpart exists for the terminase complex; letermovir is virus specific and lacks some toxicities previously observed with other anti-cytomegalovirus drugs, such as cytopenia and nephrotoxicity. The absolute bioavailability of letermovir in healthy individuals is estimated to be 94% based on a population-pharmacokinetic analysis. In contrast, oral administration of letermovir to patients undergoing hematopoietic cell transplantation results in lower exposure than that in healthy individuals. Renal or hepatic impairment does not influence the intrinsic clearance of letermovir. Co-administration of letermovir may alter the plasma concentrations of other drugs, including itself, as it acts as a substrate and inhibitor/inducer of several drug-metabolizing enzymes and transporters. In particular, attention should be paid to the drug-drug interactions between letermovir and calcineurin inhibitors or azole antifungal agents, which are commonly used in patients undergoing hematopoietic cell transplantation. This article reviews and summarizes the clinical pharmacokinetics and pharmacodynamics of letermovir, focusing on patients undergoing hematopoietic cell transplantation, healthy individuals, and specific patient subsets.

Antifungal Activity of 3-Hydrazinoquinoxaline-2-Thiol, a Novel Quinoxaline Derivative against Candida Species

Candida ranks as among the most frequently encountered fungal infections that associated with high morbidity and mortality. Quinoxaline derivatives are a group of small molecules that showed a promising antimicrobial activity. This study aimed to investigate the fungicidal effects of 3-hydrazinoquinoxaline-2-thiol against Candida in comparison with Amphotericin B in vitro as a reference. Also, we aim to assess the efficacy of 3-hydrazinoquinoxaline-2-thiol in vivo using mice oral candidiasis model. Fifty-six Candida isolates were subjected to susceptibility testing by broth microdilution method for 3-hydrazinoquinoxaline-2-thiol and Amphotericin B. Therefore, Minimal inhibitory concentrations (MIC) were assessed and compared. The oral candidiasis mice model was used to evaluate the activity of 3-hydrazinoquinoxaline-2-thiol in vivo. Microbiological evaluation of progression and ELISA were used in this study. 3-hydrazinoquinoxaline-2-thiol was more effective than Amphotericin B against most clinical isolates of Candida albicans. Higher effectiveness was seen against Candida glabrata and Candida parapsilosis isolates. However, the efficiency against Candida tropicalis isolates varies. 3-hydrazinoquinoxaline-2-thiol was also effective against Pichia kudriavzevii and Clavispora lusitaniae. 3-hydrazinoquinoxaline-2-thiol showed a good efficacy in mice model against C. albicans cells ATCC 10231. 3-hydrazinoquinoxaline-2-thiol has shown promising antifungal and anti-inflammatory activity against different Candida species. More tests and experiments are needed.

Real-World Experience with Isavuconazole in Allogeneic Stem Cell Transplantation in Spain

Invasive fungal infections (IFI) pose a significant complication after hematopoietic stem cell transplantation (HSCT). Isavuconazole (ISV) is a new generation azole with a favourable adverse effect and interaction profile approved for the treatment of invasive aspergillosis and mucormycosis. We analyzed the indications, effectiveness, adverse event profile and drug interaction management of ISV in the real-world setting in adults who received allogeneic-HSCT (allo-HSCT) within the Spanish Group of HSCT and Cell Therapy (GETH-TC). We conducted a multicenter retrospective study of all consecutive adult allo-HSCT recipients (≥18 years) who received ISV either for IFI treatment or prophylaxis, from December 2017 to August 2021, in 20 centers within the Spanish Group of Hematopoietic Stem Cell Transplantation and Cell Therapy (GETH-TC). A total of 166 adult allografted patients who received ISV from 2017 to 2021 were included. Median age was 48 years with 43% females. In 81 (49%) patients, ISV was used for treatment of IFI, and in 85 (51%) for prophylaxis. Median duration of ISV administration for IFI treatment was 57 days (range 31-126) and 86 days (range 33-196) for prophylaxis. Most frequent indication for treatment was invasive aspergillosis (78%), followed by mucormycosis (6%). Therapeutic success (45%) was the most frequent reason for ISV withdrawal. In the prophylaxis group, the resolution of IFI risk factors was the most frequent reason for withdrawal (62%). Six (7%) breakthrough IFI were reported. The majority of patients (80%) presented pharmacologic interactions. Twenty-one patients (13%) reported adverse events related to ISV, mainly liver biochemistry abnormalities, which led to ISV withdrawal in 7 patients (4%). ISV was effective and well tolerated for IFI treatment and prophylaxis, with a manageable interaction profile.

The Combination of 3-Hydrazinoquinoxaline-2-Thiol with Thymoquinone Demonstrates Synergistic Activity Against Different Candida Strains

Introduction

Candida is the primary cause of invasive fungal disease, candidiasis, especially in developed nations. The increasing resistance observed in multiple antibiotics, coupled with the prolonged process of creating new antibiotics from the ground up, emphasizes the urgent requirement for innovative methods and new compounds to combat Candida infections. Employing a treatment strategy that combines antibiotics can improve efficacy, broaden the spectrum of targeted fungal, and reduce the chances of resistance emergence. This approach shows potential in tackling the escalating problem of antibiotic resistance. The objective of this research is to explore the potential synergistic effects of combining 3-hydrazinoquinoxaline-2-thiol and thymoquinone against a variety of Candida isolates. This investigation aims to offer an understanding of the collective antimicrobial action of these compounds.

Methods

Broth microdilution was utilized to assess the Minimum Inhibitory Concentrations (MICs) of 3-hydrazinoquinoxaline-2-thiol and thymoquinone for 22 clinical Candida isolates. Following this, a checkerboard assay was employed to analyze the interaction between 3-hydrazinoquinoxaline-2-thiol and thymoquinone, with a specific focus on the Fractional Inhibitory Concentration Index (FICI).

Results

The MICs of thymoquinone and 3-hydrazinoquinoxaline-2-thiol were determined for 22 clinical Candida strains, with thymoquinone exhibiting MICs ranging from 64 to 8 µg/mL, and 3-hydrazinoquinoxaline-2-thiol displaying MICs varying from 64 to 8 µg/mL. Notably, the combination of 3-hydrazinoquinoxaline-2-thiol and thymoquinone resulted in a synergistic effect, leading to a significant reduction in MICs, with reductions of up to 64-fold with FICI below 0.5 against tested strains.

Conclusion

The prospect of using 3-hydrazinoquinoxaline-2-thiol in combination with thymoquinone as an effective solution against Candida looks encouraging. Nevertheless, to validate its practical applicability, additional comprehensive testing and experiments are imperative.

Infections in lung transplanted patients: A review

Lung transplantation can improve the survival of patients with severe chronic pulmonary disorders. However, the short- and long-term risk of infections can increase morbidity and mortality rates. A non-systematic review was performed to provide the most updated information on pathogen, host, and environment-related factors associated with the occurrence of bacterial, fungal, and viral infections as well as the most appropriate therapeutic options. Bacterial infections account for about 50% of all infectious diseases in lung transplanted patients, while viruses represent the second cause of infection accounting for one third of all infections. Almost 10% of patients develop invasive fungal infections during the first year after lung transplant. Pre-transplantation comorbidities, disruption of physical barriers during the surgery, and exposure to nosocomial pathogens during the hospital stay are directly associated with the occurrence of life-threatening infections. Empiric antimicrobial treatment after the assessment of individual risk factors, local epidemiology of drug-resistant pathogens and possible drug-drug interactions can improve the clinical outcomes.

Isavuconazole for the Treatment of Fungal Infections: A Real-life Experience From the Fungal Infection Network of Switzerland (FUNGINOS)

This analysis of 116 isavuconazole therapy courses shows that hepatic test disturbances (HTDs) were relatively frequent (29% of cases) but rarely led to treatment interruption (5%). Importantly, patients with baseline HTDs, including those attributed to a first-line triazole, did not exhibit a higher risk of subsequent HTD under isavuconazole therapy.

Pipeline of Novel Antifungals for Invasive Fungal Disease in Transplant Recipients: A Pediatric Perspective

Invasive fungal disease (IFD) remains a significant cause of morbidity and mortality in children undergoing transplantation. There is a growing armamentarium of novel antifungal agents recently approved for use or in late stages of clinical development. The overarching goal of this review is to discuss the mechanisms of action, spectrum of activity, stage of development, and pediatric-specific data for the following agents: encochleated amphotericin B deoxycholate, fosmanogepix, ibrexafungerp, isavuconazole, olorofim, opelconazole, oteseconazole, and rezafungin. Additionally, key drug attributes of these novel agents and their potential future therapeutic roles in pediatric transplant recipients are discussed.

Invasive fusariosis in patients with leukaemia in the era of mould-active azoles: increasing incidence, frequent breakthrough infections and lack of improved outcomes

OBJECTIVES

Historically, patients with leukaemia and invasive fusariosis (IF) have experienced poor outcomes in the setting of persistent immunosuppression. Herein, we retrospectively reviewed the incidence, presentation and outcomes of IF that are scarcely studied in contemporary cohorts of leukaemia patients.

METHODS

We identified adult leukaemia patients with proven or probable IF at MD Anderson Cancer Center during 2009-21. Independent risk factors for 42 day mortality after IF diagnosis were determined using a multivariable logistic regression model. Combined with historical data, the annual IF incidence density over the past 23 years was estimated using Poisson regression analysis.

RESULTS

Among 140 leukaemia patients with IF (114 proven), 118 patients (84%) had relapsed/refractory leukaemia and 124 (89%) had neutropenia at IF diagnosis. One hundred patients (71%) had pulmonary IF, 88 (63%) had disseminated IF and 48 (34%) had fungaemia. Coinfections were common (55%). Eighty-nine patients (64%) had breakthrough IF to mould-active triazoles. Most patients (84%) received combination antifungal therapy. Neutrophil recovery [adjusted OR (aOR), 0.04; 95% CI, 0.01-0.14; P < 0.0001], pulmonary IF (aOR, 3.28; 95% CI, 1.11-9.70; P = 0.032) and high SOFA score (aOR, 1.91 per 1-point increase; 95% CI, 1.47-2.50; P < 0.0001) were independent predictors of 42 day mortality outcomes. From 1998 to 2021, IF incidence density increased significantly at an annual ratio of 1.03 (95% CI, 1.01-1.06; P = 0.04).

CONCLUSIONS

IF is predominantly seen in patients with relapsed/refractory leukaemia and increasingly seen as a breakthrough infection to mould-active triazoles. Despite frequent combination antifungal therapy, high mortality rates have persisted in patients with lasting neutropenia.

Difference in immunosuppressant dose requirement when transitioning to isavuconazole from other azoles in thoracic transplant recipients

The triazole antifungal isavuconazole (ISAVU) is used for prevention and treatment of fungal infections in solid organ transplant (SOT). SOT recipients commonly need to transition from one azole to another due to breakthrough infection, toxicity, or other reasons. The purpose of our study was to evaluate the effect of ISAVU on immunosuppressant concentrations in thoracic transplant recipients when ISAVU was started de novo or transitioned from another azole. We conducted a single-center retrospective cohort study including 68 patients (51 lung, 14 heart, and 3 heart/lung transplant). Concentration to dosage ratios (C/D) of immunosuppressants were assessed at baseline, day 3, and weekly for 9 weeks. When starting ISAVU de novo, we observed a temporary doubling of tacrolimus exposure. Cyclosporine and sirolimus required dose decreases. Tacrolimus C/D increased by 110% at day 3 in patients started on ISAVU de novo then returned to baseline C/D ± 17% weeks 2-9 (n = 8). One cyclosporine patient started on ISAVU de novo had variable C/D, and C/D increased by 219% ± 72% in 2 sirolimus patients. When transitioning from other azoles, tacrolimus and cyclosporine required about twice the initial dose. After week 1, tacrolimus C/D decreased by 53% ± 6% in patients transitioned from posaconazole (n = 33), voriconazole (n = 14), or fluconazole (n = 2). Cyclosporine C/D decreased by 45% ± 16% in patients transitioning from other azoles (posaconazole [n = 2], voriconazole [n = 2], fluconazole [n = 1]). Sirolimus C/D decreased by 73% ± 13% in patients transitioned from posaconazole (n = 7). Aside from the initial loading phase, ISAVU had a lesser degree of interaction with immunosuppressants than other azoles in loading phase, ISAVU had a lesser degree of interaction with immunosuppressants than other azoles in adjustments for the 4-week period after initiating antifungal therapy with ISAVU or switching from another agent.

Thiadiazole and Thiazole Derivatives as Potential Antimicrobial Agents

BACKGROUND

This review summarizes data on heterocyclic systems with thiadiazole and thiazole fragments in molecules as promising antimicrobial agents.

INTRODUCTION

Thiadiazole and thiazole backbones are the most favored and well-known heterocycles, a common and essential feature of various drugs. These scaffolds occupy a central position and are the main structural components of numerous drugs with a wide spectrum of action. These include antimicrobial, antituberculous, anti-inflammatory, analgesic, antiepileptic, antiviral, and anticancer agents.

METHOD

The research is based on bibliosemantic and analytical methods using bibliographic and abstract databases, as well as databases of chemical compounds.

RESULT

This review reports on thiadiazole and thiazole derivatives, which have important pharmacological properties. We are reviewing the structural modifications of various thiadiazole and thiazole derivatives, more specifically, the antimicrobial activity reported over the last years, as we have taken this as our main research area. 80 compounds were illustrated, and various derivatives containing hydrazone bridged thiazole and pyrrole rings, 2-pyridine and 4-pyridine substituted thiazole derivatives, compounds containing di-, tri- and tetrathiazole moieties, spiro-substituted 4- thiazolidinone-imidazoline-pyridines were analyzed. Derivatives of 5-heteroarylidene-2,4- thiazolidinediones, fluoroquinolone-thiadiazole hybrids, and others.

CONCLUSION

1,3,4-thiadiazoles and thiazoles are valuable resource for researchers engaged in rational drug design and development in this area.

The pipeline for drugs for control and elimination of neglected tropical diseases: 2. Oral anti-infective drugs and drug combinations for off-label use

In its 'Road map for neglected tropical diseases 2021-2030', the World Health Organization outlined its targets for control and elimination of neglected tropical diseases (NTDs) and research needed to achieve them. For many NTDs, this includes research for new treatment options for case management and/or preventive chemotherapy. Our review of small-molecule anti-infective drugs recently approved by a stringent regulatory authority (SRA) or in at least Phase 2 clinical development for regulatory approval showed that this pipeline cannot deliver all new treatments needed. WHO guidelines and country policies show that drugs may be recommended for control and elimination for NTDs for which they are not SRA approved (i.e. for 'off-label' use) if efficacy and safety data for the relevant NTD are considered sufficient by WHO and country authorities. Here, we are providing an overview of clinical research in the past 10 years evaluating the anti-infective efficacy of oral small-molecule drugs for NTD(s) for which they are neither SRA approved, nor included in current WHO strategies nor, considering the research sponsors, likely to be registered with a SRA for that NTD, if found to be effective and safe. No such research has been done for yaws, guinea worm, Trypanosoma brucei gambiense human African trypanosomiasis (HAT), rabies, trachoma, visceral leishmaniasis, mycetoma, T. b. rhodesiense HAT, echinococcosis, taeniasis/cysticercosis or scabies. Oral drugs evaluated include sparfloxacin and acedapsone for leprosy; rifampicin, rifapentin and moxifloxacin for onchocerciasis; imatinib and levamisole for loiasis; itraconazole, fluconazole, ketoconazole, posaconazole, ravuconazole and disulfiram for Chagas disease, doxycycline and rifampicin for lymphatic filariasis; arterolane, piperaquine, artesunate, artemether, lumefantrine and mefloquine for schistosomiasis; ivermectin, tribendimidine, pyrantel, oxantel and nitazoxanide for soil-transmitted helminths including strongyloidiasis; chloroquine, ivermectin, balapiravir, ribavirin, celgosivir, UV-4B, ivermectin and doxycycline for dengue; streptomycin, amoxicillin, clavulanate for Buruli ulcer; fluconazole and isavuconazonium for mycoses; clarithromycin and dapsone for cutaneous leishmaniasis; and tribendimidine, albendazole, mebendazole and nitazoxanide for foodborne trematodiasis. Additional paths to identification of new treatment options are needed. One promising path is exploitation of the worldwide experience with 'off-label' treatment of diseases with insufficient treatment options as pursued by the 'CURE ID' initiative.

Recent drug development and treatments for fungal infections

Fungal infections are now becoming a hazard to individuals which has paved the way for research to expand the therapeutic options available. Recent advances in drug design and compound screening have also increased the pace of the development of antifungal drugs. Although several novel potential molecules are reported, those discoveries have yet to be translated from bench to bedside. Polyenes, azoles, echinocandins, and flucytosine are among the few antifungal agents that are available for the treatment of fungal infections, but such conventional therapies show certain limitations like toxicity, drug interactions, and the development of resistance which limits the utility of existing antifungals, contributing to significant mortality and morbidity. This review article focuses on the existing therapies, the challenges associated with them, and the development of new therapies, including the ongoing and recent clinical trials, for the treatment of fungal infections. Advancements in antifungal treatment: a graphical overview of drug development, adverse effects, and future prospects.

An extensive review on antifungal approaches in the treatment of mucormycosis

During the period of COVID-19, the occurrences of mucormycosis in immunocompromised patients have increased significantly. Mucormycosis (black fungus) is a rare and rapidly progressing fungal infection associated with high mortality and morbidity in India as well as globally. The causative agents for this infection are collectively called mucoromycetes which are the members of the order Mucorales. The diagnosis of the infection needs to be performed as soon as the occurrence of clinical symptoms which differs with types of Mucorales infection. Imaging techniques magnetic resonance imaging or computed tomography scan, culture testing, and microscopy are the approaches for the diagnosis. After the diagnosis of the infection is confirmed, rapid action is needed for the treatment in the form of antifungal therapy or surgery depending upon the severity of the infection. Delaying in treatment declines the chances of survival. In antifungal therapy, there are two approaches first-line therapy (monotherapy) and combination therapy. Amphotericin B (1) and isavuconazole (2) are the drugs of choice for first-line therapy in the treatment of mucormycosis. Salvage therapy with posaconazole (3) and deferasirox (4) is another approach for patients who are not responsible for any other therapy. Adjunctive therapy is also used in the treatment of mucormycosis along with first-line therapy, which involves hyperbaric oxygen and cytokine therapy. There are some drugs like VT-1161 (5) and APX001A (6), Colistin, SCH 42427, and PC1244 that are under clinical trials. Despite all these approaches, none can be 100% successful in giving results. Therefore, new medications with favorable or little side effects are required for the treatment of mucormycosis.

Recent Progress in Research on Mitochondrion-Targeted Antifungal Drugs: a Review

Fungal infections, which commonly occur in immunocompromised patients, can cause high morbidity and mortality. Antifungal agents act by disrupting the cell membrane, inhibiting nucleic acid synthesis and function, or inhibiting β-1,3-glucan synthase. Because the incidences of life-threatening fungal infections and antifungal drug resistance are continuously increasing, there is an urgent need for the development of new antifungal agents with novel mechanisms of action. Recent studies have focused on mitochondrial components as potential therapeutic drug targets, owing to their important roles in fungal viability and pathogenesis. In this review, we discuss novel antifungal drugs targeting mitochondrial components and highlight the unique fungal proteins involved in the electron transport chain, which is useful for investigating selective antifungal targets. Finally, we comprehensively summarize the efficacy and safety of lead compounds in clinical and preclinical development. Although fungus-specific proteins in the mitochondrion are involved in various processes, the majority of the antifungal agents target dysfunction of mitochondria, including mitochondrial respiration disturbance, increased intracellular ATP, reactive oxygen species generation, and others. Moreover, only a few drugs are under clinical trials, necessitating further exploration of possible targets and development of effective antifungal agents. The unique chemical structures and targets of these compounds will provide valuable hints for further exploiting new antifungals.

Part 2: Mucormycosis: Focus on Therapy

INTRODUCTION

Mucormycosis (MCR) a rare but life-threatening infection occurs primarily in immunocompromised hosts. Mortality rates with invasive MCR are high (>30-50%), up to 90% with disseminated disease, but lower (10-30%) with localized cutaneous disease. Due to the rarity of MCR, randomized, controlled therapeutic trials are lacking. Lipid formulations of amphotericin B (LFAB) are the mainstay of therapy but oral triazoles (posaconazole and isavuconazole) may be effective as step-down therapy or in MCR cases refractory to or intolerant of LFAB. Early surgical debridement or excision play important adjunctive roles in localized invasive disease. Control of hyperglycemia in diabetic patients, correction of neutropenia and reduction of immunosuppressive therapy is critical for optimal survival.

AREAS COVERED

The authors discuss various therapeutic options for mucormycosis. A literature search of mucormycosis therapies was performed via PubMed (up to December 2022), using the key words: invasive fungal infections; mold; mucormycosis; Mucorales; amphotericin B; isavuconazole; posaconazole.

EXPERT OPINION

Randomized, controlled therapeutic trials are lacking. Lipid formulations of amphotericin B (LFAB) are the mainstay of therapy but oral triazoles (posaconazole and isavuconazole) may be effective as step-down therapy, in MCR cases refractory to or intolerant of LFAB. We encourage early surgical debridement or excision as adjunctive measures.

A systematic review and meta-analysis of efficacy and safety of isavuconazole for the treatment and prophylaxis of invasive fungal infections

BACKGROUND

Isavuconazole is a novel triazole antifungal agent. However, the previous outcomes were highlighted by statistical heterogeneity. This meta-analysis aimed to validate the efficacy and safety of isavuconazole for the treatment and prophylaxis of invasive fungal infections (IFIs) compared with other antifungal agents (amphotericin B, voriconazole and posaconazole).

METHODS

Scopus, EMBASE, PubMed, CINAHL and Ichushi databases were searched for relevant articles that met the inclusion criteria through February 2023. Mortality, IFI rate, discontinuation rate of antifungal therapy and incidence of abnormal hepatic function were evaluated. The discontinuation rate was defined as the percentage of therapy discontinuations due to adverse events. The control group included patients who received other antifungal agents.

RESULTS

Of the 1784 citations identified for screening, 10 studies with an overall total of 3037 patients enrolled. Isavuconazole was comparable with the control group in mortality and IFI rate in the treatment and prophylaxis of IFIs, respectively (mortality, odds rate (OR) 1.11, 95% confidential interval (CI) 0.82-1.51; IFI rate, OR 1.02, 95% CI 0.49-2.12). Isavuconazole significantly reduced the discontinuation rate in the treatment (OR 1.96, 95% CI 1.26-3.07) and incidence of hepatic function abnormalities in the treatment and prophylaxis, compared with the control group (treatment, OR 2.31, 95% CI 1.41-3.78; prophylaxis, OR 3.63, 95% CI 1.31-10.05).

CONCLUSIONS

Our meta-analysis revealed that isavuconazole was not inferior to other antifungal agents for the treatment and prophylaxis of IFIs, with substantially fewer drug-associated adverse events and discontinuations. Our findings support the use of isavuconazole as the primary treatment and prophylaxis for IFIs.

Studies on the inhibitory effect of isavuconazole on flumatinib metabolism in vitro and in vivo

As the validated agent for the treatment of chronic myelogenous leukemia (CML), flumatinib is a novel oral tyrosine kinase inhibitor (TKI) with higher potency and selectivity for BCR-ABL1 kinase compared to imatinib. Many patients experience aspergillosis infection and they may start using isavuconazole, which is an inhibitor of CYP3A4. However, there is no study on their interaction in vitro and in vivo. In the present study, the concentrations of flumatinib and its major metabolite M1 were rapidly determined using an stable ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. The half-maximal inhibitory concentration (IC₅₀) was 6.66 μM in human liver microsomes (HLM), while 0.62 μM in rat liver microsomes (RLM) and 2.90 μM in recombinant human CYP3A4 (rCYP3A4). Furthermore, the mechanisms of inhibition of flumatinib in human liver microsomes, rat liver microsomes and rCYP3A4 by isavuconazole were mixed. Moreover, ketoconazole, posaconazole, and isavuconazole showed more potent inhibitory effects than itraconazole, fluconazole, and voriconazole on HLM-mediated flumatinib metabolism. In pharmacokinetic experiments of rats, it was observed that isavuconazole could greatly change the pharmacokinetic parameters of flumatinib, including AUC_(0-t), AUC_(0-∞), C_max and CLz/F, but had no effect on the metabolism of M1. According to the results of in vitro and in vivo studies, the metabolism of flumatinib was inhibited by isavuconazole, suggesting that isavuconazole may raise the plasma concentration of flumatinib. Thus, it is important to take special care of the interactions between flumatinib and isavuconazole in clinical applications.

Population Pharmacokinetics, Exposure-Safety, and Probability of Target Attainment Analyses for Isavuconazole in Japanese Patients With Deep-Seated Mycoses

Isavuconazonium sulfate is the water-soluble prodrug of the novel, broad-spectrum, triazole antifungal agent isavuconazole. Its pharmacokinetics (PK) and exposure-response relationship have been well investigated, but not in a Japanese patient population. The objectives of this analysis were to (1) develop a population PK model for Japanese patients with deep-seated mycoses and healthy subjects, and to identify significant covariates; (2) determine the probability of PK-pharmacodynamic (PK-PD) target attainment in Japanese patients by a clinical dosing regimen; and (3) evaluate the exposure-safety relationship of isavuconazole in Japanese patients. Data from 2 phase 1 studies and 1 phase 3 study in Japanese patients were pooled to develop the population PK model using NONMEM. The PK of isavuconazole in Japanese patients was best described as a 2-compartment model with a Weibull absorption function and first-order elimination. The identified covariates on clearance were creatinine clearance and lean body mass. The probability of target attainment showed that >90% of simulated Japanese patients would achieve the PK-PD target, an exposure index corresponding to 50% survival of nonneutropenic infected mice, with minimal inhibitory concentration values of ≤1 mg/L according to Clinical and Laboratory Standards Institute methodology and of ≤2 mg/L according to European Committee on Antimicrobial Susceptibility Testing methodology by the clinical dosing regimen. No apparent relationships were found for any of the exposure parameters of isavuconazole with any assessed safety end points in Japanese patients. Taken together, the clinical dosing regimen is appropriate for the treatment of Japanese patients with deep-seated mycoses.

Population Pharmacokinetics of Isavuconazole in Critical Care Patients with COVID-19-Associated Pulmonary Aspergillosis and Monte Carlo Simulations of High Off-Label Doses

Isavuconazole is a triazole antifungal agent recently recommended as first-line therapy for invasive pulmonary aspergillosis. With the COVID-19 pandemic, cases of COVID-19-associated pulmonary aspergillosis (CAPA) have been described with a prevalence ranging from 5 to 30%. We developed and validated a population pharmacokinetic (PKpop) model of isavuconazole plasma concentrations in intensive care unit patients with CAPA. Nonlinear mixed-effect modeling Monolix software were used for PK analysis of 65 plasma trough concentrations from 18 patients. PK parameters were best estimated with a one-compartment model. The mean of ISA plasma concentrations was 1.87 [1.29-2.25] mg/L despite prolonged loading dose (72 h for one-third) and a mean maintenance dose of 300 mg per day. Pharmacokinetics (PK) modeling showed that renal replacement therapy (RRT) was significantly associated with under exposure, explaining a part of clearance variability. The Monte Carlo simulations suggested that the recommended dosing regimen did not achieve the trough target of 2 mg/L in a timely manner (72 h). This is the first isavuconazole PKpop model developed for CAPA critical care patients underlying the need of therapeutic drug monitoring, especially for patients under RRT.

Efficacy and safety of isavuconazole against deep-seated mycoses: A phase 3, randomized, open-label study in Japan

OBJECTIVES

Isavuconazole is a convenient triazole antifungal agent with a broad antifungal spectrum. A randomized, open-label study (ClinicalTrials.gov, NCT03471988) was conducted to evaluate the efficacy and safety of isavuconazole in Japanese patients with deep-seated mycoses.

PATIENTS AND METHODS

In Cohort A, patients with aspergillosis (chronic pulmonary aspergillosis and invasive aspergillosis) were randomized in a 2:1 ratio to isavuconazole or voriconazole, and in Cohort B, patients with cryptococcosis and mucormycosis were assigned to isavuconazole for up to 84 days of treatment. The overall outcome was evaluated according to the clinical, radiological, and mycological responses at Days 42 and 84 and at the end of treatment (EOT).

RESULTS

A total of 103 participants were enrolled and received the study drug. The overall response rate of patients with chronic pulmonary aspergillosis in the isavuconazole (52 patients) and voriconazole (27 patients) groups was 82.7% and 77.8% at EOT, respectively. The response rate in patients with cryptococcosis (10 patients, isavuconazole group only) was 90.0%. One of three participants with invasive aspergillosis and one of three participants with mucormycosis responded in the isavuconazole group. In the safety evaluation, the incidence of adverse events in participants with chronic pulmonary aspergillosis was similar in both groups. Adverse drug reactions were reported in 32 (61.5%) patients receiving isavuconazole and 23 (85.2%) patients receiving voriconazole.

CONCLUSIONS

Isavuconazole showed efficacy and safety in Japanese patients with chronic pulmonary aspergillosis and cryptococcosis, for which the drug is not currently indicated.

Multidisciplinary approach in diagnosis and treatment of COVID-19-associated mucormycosis: a description of current reports

Background

We reviewed the epidemiology, risk factors, pathophysiology, and clinical presentations of coronavirus disease 2019 (COVID-19)-associated mucormycosis (CAM), then discussed the importance of rapid diagnosis and treatment facilitated by multidisciplinary approach.

Main body

India has reported world’s highest number of CAM cases where Rhizopus arrhizus was the most predominant etiology. CAM caused by Rhizopus microsporus was the most common from the rest of the world. Multiple risk factors for CAM were identified including diabetes mellitus, inappropriate corticosteroid use, COVID-19-related hypoxia, and lung damage.

Rhino-orbito-cerebral mucormycosis (ROCM) accounted for almost 90% of CAM in India while 64% of global cases were ROCM. Less than 10% of CAM from India were pulmonary while the rest of the world reported 21% of pulmonary CAM.

CAM is diagnosed by confirmed SARS-CoV2 infection along with clinical, radiological, histopathological, and/or microbiological evidence of mucormycosis. In patients with risks of CAM and associated symptoms, CT or MRI are recommended. If ROCM is suspected, endoscopy and biopsy are recommended. If pulmonary CAM is suspected, tissue biopsies, nasal samples, or bronchoalveolar lavage is recommended with histopathological exams.

Early diagnosis, surgical, and pharmaceutical interventions are key to treat mucormycosis. Upon diagnosis, antifungal therapy with liposomal amphotericin B (IV) is considered first-line of therapy. Alternatively, posaconazole (PO/IV) or isavuconazole (PO/IV) can be used.

Conclusion

Treating CAM requires a multidisciplinary approach for early diagnosis and prompt initiation of interventions to maximize patient’s chance of survival.

Acute Lymphoblastic Leukemia and Invasive Mold Infections: A Challenging Field

Acute lymphoblastic leukemia (ALL) patients comprise a highly immunocompromised group due to factors associated either with the treatment or the disease itself. Invasive mold infections (IMIs) are considered to be responsible for higher morbidity and mortality rates in patients with hematologic malignancies, including ALL. Defining the exact incidence of IMIs in ALL patients has been rather complicated. The available literature data report a highly variable incidence of IMIs, ranging from 2.2% to 15.4%. Although predisposing factors for IMIs in the setting of ALL are ill-defined, retrospective studies have indicated that a longer duration of neutropenia, treatment with high-dose corticosteroids, and a lack of antimold prophylaxis are associated with an increased risk of IMIs. Additionally, the influence of novel ALL treatments on the susceptibility to fungal infections remains obscure; however, initial data suggest that these treatments may induce prolonged neutropenia and thus an increased risk of IMIs. Administering primary antimold prophylaxis in these patients has been challenging since incorporating azole antifungal agents is troublesome, considering the drug-to-drug interactions (DDIs) and increased toxicity that may occur when these agents are coadministered with vincristine, a fundamental component of ALL chemotherapy regimens. Isavuconazole, along with several novel antifungal agents such as rezafungin, olorofim, and manogepix, may be appealing as primary antimold prophylaxis, given their broad-spectrum activity and less severe DDI potential. However, their use in ALL patients needs to be investigated through more clinical trials. In summary, this review outlines the epidemiology of IMI and the use of antifungal prophylaxis in ALL patients.

Real-World Comparison of Isavuconazole and Voriconazole in Terms of the Need for Dosage Adjustments Guided by Clinical Pharmacological Advice During Primary Prophylaxis of Invasive Fungal Infections in Pediatric Patients with Hemato-Oncological Malignancies

BACKGROUND

Limited evidence concerning optimal azole dosing regimens currently exists for antifungal prophylaxis in hemato-oncological pediatric patients.

METHODS

Hemato-oncological children receiving intravenous or oral isavuconazole or voriconazole for primary antifungal prophylaxis at IRCCS Azienda Ospedaliero-Universitaria of Bologna during November 2020 to October 2021 and undergoing CPA programs based on real-time therapeutic drug monitoring (TDM) were retrospectively analyzed. CPAs for isavuconazole and voriconazole and the number of dosage adjustments were collected. Normalized trough concentrations [(C min )/dose/kg] were calculated for both drugs at each TDM assessment, and the coefficient of variation was determined. The efficacy and safety of the drugs were evaluated.

RESULTS

Sixteen hemato-oncological pediatric patients received azole prophylaxis (mean age and weight: 9.1 ± 4.9 years and 32.6 ± 16.0 kg; 6 isavuconazole and 10 voriconazole). Sixty and 89 CPAs were delivered as isavuconazole and voriconazole, respectively. Dosage adjustments were needed in 3.3% of cases for isavuconazole and 53.9% of cases for voriconazole ( P < 0.001). At first TDM, achievement of the desired target during standard dosing regimens was higher for isavuconazole (83.3%) than for voriconazole (10.0%; P = 0.008). Dispersion of normalized concentrations was higher for voriconazole (CV = 139.1% vs. CV = 79.4%). Elevation of ALT and aspartate aminotransferase levels between baseline and the third month was higher in patients receiving voriconazole (median, 28 vs. 90 U/L; P = 0.038, and 19 vs. 65.5 U/L; P = 0.002).

CONCLUSIONS

Our findings suggest that there is limited variability in isavuconazole exposure in hemato-oncological pediatric patients receiving azole prophylaxis , resulting in a low need for CPA-guided dosage adjustments.

A Pharmacokinetic Bioequivalence Study Comparing Different-Strength and -Size Capsules of Isavuconazonium Sulfate in Healthy Japanese Subjects

Isavuconazonium sulfate is the water-soluble prodrug of the novel, broad-spectrum, triazole antifungal agent isavuconazole. A size 0 elongated hard capsule containing 100 mg equivalent of isavuconazole is the currently marketed oral formulation in countries where it is approved. An alternative oral formulation, based on a lower-strength and smaller-size capsule, is required for pediatric and adolescent patients, as well as for some adult Japanese patients, especially those with difficulties swallowing larger capsules. This study was conducted to evaluate the bioequivalence of a size 0 elongated capsule containing 100 mg equivalent of isavuconazole and a size 3 capsule containing 40 mg equivalent of isavuconazole, after administration of 200 mg equivalent of isavuconazole (5 size 3 capsules or 2 size 0 elongated capsules) under fasted conditions. Bioequivalence of isavuconazole between the formulations was demonstrated, since point estimates (90%CI) for the ratio of the size 0 elongated capsules vs the size 3 capsules for maximum plasma concentration and area under the plasma concentration-time curve from time 0 to the last quantifiable concentration were within the acceptable range of 0.8 to 1.25. It was confirmed that both formulations were well tolerated, and no new safety signals were observed in healthy Japanese adult male subjects.

Development and research progress of anti-drug resistant fungal drugs

With the widespread use of immunosuppressive agents and the increase in patients with severe infections, the incidence of fungal infections worldwide has increased year by year. The fungal pathogens Candida albicans, Cryptococcus neoformans and Aspergillus fumigatus cause a total of more than 1 million deaths each year. Long-term use of antifungal drugs can easily lead to fungal resistance, and the prevalence of drug-resistant fungi is a major global health challenge. In order to effectively control global fungal infections, there is an urgent need for new drugs that can exert effective antifungal activity and overcome drug resistance. We must promote the discovery of new antifungal targets and drugs, and find effective ways to control drug-resistant fungi through different ways, so as to reduce the threat of drug-resistant fungi to human life, health and safety. In the past few years, certain progress has been made in the research and development of antifungal drugs. In addition to summarizing some of the antifungal drugs currently approved by the FDA, this review also focuses on potential antifungal drugs, the repositioned drugs, and drugs that can treat drug-resistant bacteria and fungal infections, and provide new ideas for the development of antifungal drugs in the future.

Experimental models for pharmacokinetic and pharmacodynamic studies of antifungals used in cryptococcosis treatment

Studies on cryptococcosis in the mammal animal model have demonstrated the occurrence of central nervous system infection and similarities in fungal pathogenicity with clinical and immunological features of the human infection. Although there is still a lack of studies involving pharmacokinetics (PK) and pharmacodynamics (PD) in animal models of cryptococcosis in the literature, these experimental models are useful for understanding this mycosis and antifungal effectiveness in improving the therapeutic schemes. The scope of this review is to describe and discuss the main mammal animal models for PK and PD studies of antifungals used in cryptococcosis treatment. Alternative models and computational methods are also addressed. All approaches for PK/PD studies are relevant to investigating drug-infection interaction and improving cryptococcosis therapy.

Pharmacokinetics of isavuconazole in healthy cats after oral and intravenous administration

Background

Isavuconazole is a triazole antifungal drug that has shown good efficacy in human patients. Absorption and pharmacokinetics have not been evaluated in cats.

Objectives

To determine the pharmacokinetics of isavuconazole in cats given a single IV or PO dose.

Animals

Eight healthy, adult research cats.

Methods

Four cats received 100 mg capsules of isavuconazole PO. Four cats received 5 mg/kg isavuconazole solution IV. Serum was collected at predetermined intervals for analysis using ultra‐high performance liquid chromatography‐tandem mass spectrometry. Data were analyzed using a 2‐compartment uniform weighting pharmacokinetic analysis with lag time for PO administration and a 2 compartment, 1/y² weighting for IV administration. Predicted 24 and 48‐hour dosing intervals of 100 mg isavuconazole administered PO were modeled and in vitro plasma protein binding was assessed.

Results

Both PO and IV drug administration resulted in high serum concentrations. Intravenous and PO formulations of isavuconazole appear to be able to be used interchangeably. Peak serum isavuconazole concentrations occurred 5 ± 3.8 hours after PO administration with an elimination rate half‐life of 66.2 ± 55.3 hours. Intersubject variability was apparent in both the PO and IV groups. Two cats vomited 6 to 8 hours after PO administration. No adverse effects were observed in the IV group. Oral bioavailability was estimated to be approximately 88%. Serum protein binding was calculated to be approximately 99.0% ± 0.03%.

Conclusions and Clinical Importance

Isavuconazole might prove to be useful in cats with fungal disease given its favorable pharmacokinetics. Additional studies on safety, efficacy, and tolerability of long‐term isavuconazole use are needed.

Prospective Medicines against the Widespread, Emergent and Multidrug-Resistant Opportunistic Fungal Pathogen Candida auris: A Breath of Hope

The emergence of the pathogen Candida auris is a real concern worldwide, especially due to its multidrug resistance profile, besides the difficulties in establishing the correct identification by conventional laboratory methods and its capacity of causing outbreaks in healthcare settings. The limited arsenal of available antifungal drugs, coupled with the lack of momentum for the development of new reagents, represent a challenge in the management of such a pathogen. In this perspective, we have focused on discussing new, promising treatment options for C. auris infections. These novel drugs include an antifungal agent already approved for medical use in the United States of America, compounds that are already in clinical trials and those with potential for repurposing use against this important fungal pathogen.

Isavuconazole Therapeutic Drug Monitoring in critically ill ICU patients - a monocentric retrospective analysis

BACKGROUND

The broad-spectrum triazole isavuconazole is used for the treatment of invasive aspergillosis and mucormycosis. Data regarding human plasma concentrations in clinical routine of the drug are rare.

OBJECTIVES

Plasma concentrations of isavuconazole were determined in critically ill ICU patients while considering different patients' characteristics.

METHODS

Retrospective analysis of isavuconazole plasma concentrations were obtained as part of routine therapeutic drug monitoring (TDM) of ICU patients with invasive aspergillosis or other fungal infections treated with isavuconazole. Plasma levels 0-4h after last dosing were defined as peak levels (C_max ), those 20-28h after last dosing as trough levels (C_min ).

RESULTS

Overall, 223 isavuconazole levels of 41 patients were analysed, divided into 141 peak levels and 82 trough levels. The overall median C_max was 2.36 μg/mL (mean 2.43 μg/mL, range 0.41 - 7.79 μg/mL) and the overall median C_min was 1.74 μg/mL (mean 1.77 μg/mL, range 0.24 - 4.96 μg/mL). In total, 31.7% of the C_min values of the total cohort were below the plasma target concentrations of 1 μg/mL, defined as EUCAST antifungal clinical breakpoint for Aspergillus fumigatus. Both peak and trough plasma levels of isavuconazole were significantly lower among patients with a body-mass-index (BMI) ≥ 25. In addition, a significant correlation was observed between isavuconazole trough levels and sepsis-related organ failure assessment (SOFA) score.

CONCLUSIONS

This study shows that isavuconazole plasma concentrations vary in critical ill ICU patients. Significantly lower isavuconazole levels were associated with elevated BMI and higher SOFA score indicating a need of isavuconazole TDM in this specific patient population.

Augmenting Azoles with Drug Synergy to Expand the Antifungal Toolbox

Fungal infections impact the lives of at least 12 million people every year, killing over 1.5 million. Wide-spread use of fungicides and prophylactic antifungal therapy have driven resistance in many serious fungal pathogens, and there is an urgent need to expand the current antifungal arsenal. Recent research has focused on improving azoles, our most successful class of antifungals, by looking for synergistic interactions with secondary compounds. Synergists can co-operate with azoles by targeting steps in related pathways, or they may act on mechanisms related to resistance such as active efflux or on totally disparate pathways or processes. A variety of sources of potential synergists have been explored, including pre-existing antimicrobials, pharmaceuticals approved for other uses, bioactive natural compounds and phytochemicals, and novel synthetic compounds. Synergy can successfully widen the antifungal spectrum, decrease inhibitory dosages, reduce toxicity, and prevent the development of resistance. This review highlights the diversity of mechanisms that have been exploited for the purposes of azole synergy and demonstrates that synergy remains a promising approach for meeting the urgent need for novel antifungal strategies.

Novel 1, 2, 4-Triazoles as Antifungal Agents

The development of innovative antifungal agents is essential. Some fungicidal agents are no longer effective due to resistance development, various side effects, and high toxicity. Therefore, the synthesis and development of some new antifungal agents are necessary. 1,2,4-Triazole is one of the most essential pharmacophore systems between five-membered heterocycles. The structure-activity relationship (SAR) of this nitrogen-containing heterocyclic compound showed potential antifungal activity. The 1,2,4-triazole core is present as the nucleus in a variety of antifungal drug categories. The most potent and broad activity of triazoles have confirmed them as pharmacologically significant moieties. The goal of this review is to highlight recent developments in the synthesis and SAR study of 1,2,4-triazole as a potential fungicidal compound. In this study, we provide the results of a biological activity evaluation using various structures and figures. Literature investigation showed that 1, 2, 4-triazole derivatives reveal the extensive span of antifungal activity. This review will assist researchers in the development of new potential antifungal drug candidates with high effectiveness and selectivity.

Pharmacokinetics, Safety, and Tolerability of Single and Multiple Doses of Isavuconazonium Sulfate in Healthy Adult Japanese Subjects

Isavuconazonium sulfate is the water‐soluble prodrug of the novel, broad‐spectrum, triazole antifungal agent isavuconazole. This was a first‐in‐Japanese study assessing the pharmacokinetics, safety, and tolerability of isavuconazonium sulfate. The study was conducted in 2 parts: part 1 (single ascending dose; 100‐, 200‐, and 400‐mg equivalent of isavuconazole oral or intravenous administration); and part 2 (multiple doses for 16 days; 200‐mg equivalent of isavuconazole oral or intravenous administration; once‐daily administration with a loading regimen every 8 hours for the first 48 hours). A total of 60 and 16 subjects were randomized in part 1 and part 2, respectively. Observed clearance was lower in this study compared to what was previously reported in predominantly White populations and similar to clearance in non‐Japanese Asian populations. The range of the plasma isavuconazole concentration in this study was within the range of the pivotal phase 3 study, with no relationship between isavuconazole exposure and either efficacy or safety. There were no serious adverse events, and all reported treatment‐emergent adverse events were of mild intensity. This study confirmed that isavuconazonium sulfate was safe and well tolerated in healthy adult Japanese subjects.

Acalabrutinib CYP3A mediated Drug-Drug Interactions: Clinical Evaluations and Physiologically-Based Pharmacokinetic Modeling to inform dose adjustment strategy

AIMS

Clinical drug interaction studies with itraconazole and rifampicin demonstrated acalabrutinib is a sensitive substrate of CYP3A. A PBPK model was developed based on the data of these studies. One of the active CYP3A metabolite ACP-5862 was identified but never studied in a drug interaction scenario. This study aims to evaluate both parent and metabolite exposure change with coadministration of moderate CYP3A inhibitors and its impact on safety and efficacy.

METHOD

In an open label, randomized, 2-period study, we investigated the effect of coadministration of fluconazole or isavuconazole on the pharmacokinetics of acalabrutinib. BTK receptor occupancy and safety was compared between different treatments. Experimental data was compared to PBPK simulation results.

RESULT

Least square means of Acalabrutinib Cmax and AUC increased 1.37(1.14-1.64)and 1.60(1.45-1.77)-fold in the presence of isavuconazole and 1.48(1.10-1.98) and 2.16(1.94-2.40) fold in the presence of fluconazole, respectively. For ACP-5862, these values are 0.72(0.63-0.82) and 0.91(0.86-0.97) fold for isavuconazole and 0.65(0.49-0.87) and 0.95(0.91-0.99) fold for fluconazole coadministration. The PBPK model was able to recover acalabrutinib and ACP-5862 PK profiles in the study. BTK receptor occupancy change was minimal in the presence of isavuconazole. There were no deaths, SAEs, or subject discontinuation due to AEs in this study. Mild (Grade 1) AEs were the only AEs reported during the study, by 17% of the study population.

CONCLUSION

Our results demonstrated the impact of fluconazole and isavuconazole on the pharmacokinetics of acalabrutinib and ACP-5862 and suggests no dose adjustment is needed for concomitant administration with moderate CYP3A inhibitors. Current PBPK model can be used to propose dose adjustment for drug interactions via CYP3A.

Drug Resistance and Novel Therapeutic Approaches in Invasive Candidiasis

Candida species are the leading cause of invasive fungal infections worldwide and are associated with acute mortality rates of ~50%. Mortality rates are further augmented in the context of host immunosuppression and infection with drug-resistant Candida species. In this review, we outline antifungal drugs already in clinical use for invasive candidiasis and candidaemia, their targets and mechanisms of resistance in clinically relevant Candida species, encompassing not only classical resistance, but also heteroresistance and tolerance. We describe novel antifungal agents and targets in pre-clinical and clinical development, including their spectrum of activity, antifungal target, clinical trial data and potential in treatment of drug-resistant Candida. Lastly, we discuss the use of combination therapy between conventional and repurposed agents as a potential strategy to combat the threat of emerging resistance in Candida.

Dental and Oral Manifestations of COVID-19 Related Mucormycosis: Diagnoses, Management Strategies and Outcomes

It has been nearly two years since the pandemic caused by the novel coronavirus disease (COVID-19) has affected the world. Several innovations and discoveries related to COVID-19 are surfacing every day and new problems associated with the COVID-19 virus are also coming to light. A similar situation is with the emergence of deep invasive fungal infections associated with severe acute respiratory syndrome 2 (SARS-CoV-2). Recent literature reported the cases of pulmonary and rhino-cerebral fungal infections appearing in patients previously infected by COVID-19. Histopathological analysis of these cases has shown that most of such infections are diagnosed as mucormycosis or aspergillosis. Rhino-orbital-cerebral mucormycosis usually affects the maxillary sinus with involvement of maxillary teeth, orbits, and ethmoidal sinuses. Diabetes mellitus is an independent risk factor for both COVID-19 as well as mucormycosis. At this point, there is scanty data on the subject and most of the published literature comprises of either case reports or case series with no long-term data available. The aim of this review paper is to present the characteristics of COVID-19 related mucormycosis and associated clinical features, outcome, diagnostic and management strategies. A prompt diagnosis and aggressive treatment planning can surely benefit these patients.

Consensus guidelines for the diagnosis and management of invasive fungal disease due to moulds other than Aspergillus in the haematology/oncology setting, 2021

Invasive fungal disease (IFD) due to moulds other than Aspergillus is a significant cause of mortality in patients with malignancies or post haemopoietic stem cell transplantation. The current guidelines focus on the diagnosis and management of the common non-Aspergillus moulds (NAM), such as Mucorales, Scedosporium species (spp.), Lomentospora prolificans and Fusarium spp. Rare but emerging NAM including Paecilomyces variotii, Purpureocillium lilacinum and Scopulariopsis spp. are also reviewed. Culture and histological examination of tissue biopsy specimens remain the mainstay of diagnosis, but molecular methods are increasingly being used. As NAM frequently disseminate, blood cultures and skin examination with biopsy of any suspicious lesions are critically important. Treatment requires a multidisciplinary approach with surgical debridement as a central component. Other management strategies include control of the underlying disease/predisposing factors, augmentation of the host response and the reduction of immunosuppression. Carefully selected antifungal therapy, guided by susceptibility testing, is critical to cure. We also outline novel antifungal agents still in clinical trial which offer substantial potential for improved outcomes in the future. Paediatric recommendations follow those of adults. Ongoing epidemiological research, improvement in diagnostics and the development of new antifungal agents will continue to improve the poor outcomes that have been traditionally associated with IFD due to NAM.

Intricate isavuconazole therapy of a subcutaneous nodule caused by Alternaria infectoria in a heart transplant recipient

Invasive fungal infections have appeared to be increasingly emergent in immunocompromised patients, especially in solid organ transplant (SOT) recipients. The Alternaria genus encompasses more than 80 dematiaceus species. Among them, Alternaria alternata and Alternaria infectoria are the most frequent isolated as responsible for infection in humans. To our knowledge, we report the first case of a heart transplant recipient suffering from subcutaneous nodule caused by Alternaria infectoria and who was treated with isavuconazole. Despite all the promises of this new azole drug, one should keep in mind the potential great variability of the inter-individual responses for such complex patients. We demonstrate herein how it can be challenging to manage Alternaria infection in SOT recipients. More comprehensive studies and recommendations are expected in the context of Alternaria infections.

Invasive fungal infections in acute and chronic liver impairment: A systematic review

Patients with acute and chronic liver impairment are susceptible to invasive fungal infections such as candidemia and invasive pulmonary aspergillosis as a result of cirrhosis-associated immune dysfunction, humoral immunodeficiency, cell-mediated dysfunction and systemic inflammation. Besides classical risk factors for invasive fungal infection, acute-on-chronic liver failure, corticosteroid use, gastrointestinal bleeding, and prophylactic use of antibiotics are all additional conditions which are related to the potential development of fungal infections. Therefore, high-risk patients should be carefully followed by microbiological surveillance including cultures but also by imaging and fungal biomarkers for providing early diagnosis. Echinocandins are still the mainstay and first line antifungal therapy in cases of invasive candidiasis. Due to concerns of liver toxicity and in cases of renal impairment liposomal amphotericin B is a suitable alternative to voriconazole in patients with invasive pulmonary aspergillosis. Although, data of isavucoanzole and posaconazole use in those patients are also promising more specific studies in the subgroup of patients with liver impairment are needed. Especially, due to the late diagnosis and multiple organ dysfunction usually present in patients with liver impairment morbidity and mortality rates remain high. Based on the broad spectrum of diverse reports with varying content and quality and in some cases lack of evidence we performed a systematic review on this topic.

Sporotrichosis in a U.S. Army Basic Trainee

Lymphocutaneous sporotrichosis is a mycotic disease caused by traumatic inoculation of the dimorphic fungus Sporothrix schenckii, found ubiquitously in decaying vegetation. The potential for outbreaks, difficulty with timely diagnosis, as well as the prolonged treatment course and recovery from surgical intervention can have a substantial impact on the medical readiness of service members. Treatment with the antifungal therapy of choice, itraconazole, requires close patient monitoring for the duration of treatment for clinical response, drug tolerance, as well as therapeutic drug levels. We present a case of a U.S. Army enlistee with sporotrichosis contracted during basic training, highlighting the impact of delayed diagnosis and prolonged treatment course and recovery on medical readiness.

Successful long-term therapy of mucormycosis with isavuconazole

We present a case of a 55-year-old poorly controlled diabetic who presented to the hospital with facial pain, ophthalmoplegia, vision changes, and diabetic ketoacidosis and was diagnosed with rhinocerebral mucormycosis due to Rhizopus microsporus. He was started on liposomal amphotericin B and micafungin and went for nasal endoscopy and debridement, but the infection had progressed through the base of the skull and he received the maximum tolerated debridement. Posaconazole was added and discontinued due to elevated liver chemistry tests and was replaced with oral isavuconazole. After 6 weeks of therapy with liposomal amphotericin B and isavuconazole, he was switched to oral isavuconazole monotherapy. He underwent 30 sessions of hyperbaric oxygen therapy. Imaging showed improvement with subsequent biopsies that were negative for mucormycosis. At 13 months of therapy, his monotherapy was discontinued. He continues to have long-term sequelae including left facial droop and inability to close his left eye.

Isavuconazole and Liposomal Amphotericin B as Successful Combination Therapy of Refractory Invasive Candidiasis in a Liver Transplant Recipient: A Case Report and Literature Review

Invasive fungal infections in liver transplant recipients are associated with elevated morbidity and mortality and pose a challenge to the treating physicians. Despite of lacking clinical data, the use of antifungal combination therapy is often considered to improve response rates in an immunocompromised patient population. We herein report a case of refractory invasive candidiasis in a liver transplant recipient treated successfully with a combination of isavuconazole und high-dose liposomal amphotericin B. The antimycotic combination treatment was able to clear a bloodstream infection with C. glabrata and led to regression of bilomas among tolerable side effects. The use of the above-mentioned antifungal combination therapy in a liver transplant recipient has not been reported previously. This case highlights the efficacy and safety of antifungal combination therapy in immunocompromised patients with refractory invasive candidiasis.

Mucormycosis in Indian COVID-19 Patients: Insight into Its Patho-Genesis, Clinical Manifestation, and Management Strategies

Mucormycosis in patients who have COVID-19 or who are otherwise immunocompromised has become a global problem, causing significant morbidity and mortality. Infection is debilitating and fatal, leading to loss of organs and emotional trauma. Radiographic manifestations are not specific, but diagnosis can be made through microscopic examination of materials collected from necrotic lesions. Treatment requires multidisciplinary expertise, as the fungus enters through the eyes and nose and may even reach the brain. Use of the many antifungal drugs available is limited by considerations of resistance and toxicity, but nanoparticles can overcome such limitations by reducing toxicity and increasing bioavailability. The lipid formulation of amphotericin-B (liposomal Am-B) is the first-line treatment for mucormycosis in COVID-19 patients, but its high cost and low availability have prompted a shift toward surgery, so that surgical debridement to remove all necrotic lesions remains the hallmark of effective treatment of mucormycosis in COVID-19. This review highlights the pathogenesis, clinical manifestation, and management of mucormycosis in patients who have COVID-19.

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.