Isavuconazole: A Review in Invasive Aspergillosis and Mucormycosis

Efficacy and safety of isavuconazole versus voriconazole for the treatment of invasive fungal infections: a meta-analysis with trial sequential analysis

BACKGROUND

Isavuconazole has been used to treat invasive fungal infections, however, it is unclear whether the efficacy of isavuconazole is superior to that of voriconazole. The purpose of this meta-analysis was to assess the efficacy and safety of isavuconazole compared to voriconazole in treating invasive fungal infections.

METHODS

Electronic databases, including PubMed, EMBASE, Cochrane Library, and Web of Science, were searched to identify relevant studies. Studies evaluating the effect of isavuconazole in the treatment of patients with invasive fungal infections were included. Pooled rates of overall response, all-cause mortality, drug-related adverse events (AEs), and discontinuation due to drug-related AEs were calculated.

RESULTS

Seven studies involving 890 patients were included. Meta-analysis showed that there was no significant difference between isavuconazole and voriconazole in overall response (risk ratio [RR]: 1.02, 95% confidence interval [CI]: 0.83 to 1.25, p = 0.86) and all-cause mortality (RR: 0.95, 95% CI: 0.78 to 1.16, p = 0.61). However, isavuconazole had a significantly lower incidence of drug-related AEs (RR: 0.70, 95% CI: 0.61 to 0.81, p < 0.001) and discontinuation due to drug-related AEs (RR: 0.56, 95% CI: 0.39 to 0.82, p = 0.003) compared with voriconazole. Trial sequential analysis (TSA) confirmed that the difference between isavuconazole and voriconazole in discontinuation due to drug-related AEs need further valiadation, but the results of other outcomes were conclusive.  < 0.001) and discontinuation due to drug-related AEs (RR: 0.56, 95% CI: 0.39 to 0.82, p = 0.003) compared with voriconazole. Trial sequential analysis (TSA) confirmed that the difference between isavuconazole and voriconazole in discontinuation due to drug-related AEs needs further validation, but the results of other outcomes were conclusive.

CONCLUSIONS

Our findings support the use of isavuconazole as the primary therapy for invasive fungal infections. More research is needed to compare the discontinuation rates of isavuconazole and voriconazole.

The efficacy and safety of first-line monotherapies in primary therapy of invasive aspergillosis: a systematic review

Objective

Several antifungals are available for the treatment of patients with invasive aspergillosis (IA). This study aims to evaluate the relative efficacy and safety of the first-line monotherapies in primary therapy of IA through network meta-analysis (NMA).

Methods

We systematically searched PubMed, Embase, Web of Science, Cochrane Library, China National Knowledge Infrastructure, VIP database, Wanfang database, and China Biology Medicine for randomized controlled trials (RCTs) up to July 2023 that evaluated the efficacy and safety of monotherapies. We performed NMA with a frequentist random effects model and assessed the certainty of evidence using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach. Primary outcomes were the all-cause mortality at week 12, and secondary outcomes included overall response rate, and incidence of adverse events (AEs) and severe adverse events (SAEs).

Results

A total of three RCTs involving 1,368 participants (four antifungals) were included. The NMA showed that compared to amphotericin B deoxycholate (D-AmB), the triazoles (posaconazole (POS), isavuconazole (ISA) and voriconazole (VCZ)) can improve the overall response rate in primary therapy of IA, but only VCZ and ISA can reduce the all-cause mortality at week 12 for patients with proven and probable IA (VCZ vs D-AmB: RR = 0.66, 95%CI = 0.47-0.93, moderate certainty; ISA vs D-AmB: RR = 0.52, 95%CI = 0 .31-0.86, low certainty). ISA (SUCRA = 93.50%; mean rank, 1.20) seemed to be the most effective therapy in the above population. As to proven, probable, and possible IA patients, the triazoles were superior to D-AmB in terms of reducing all-cause mortality. Furthermore, the risk of AEs and SAEs was comparable for the three triazoles, but the risk of SAEs was significantly higher for D-AmB than others.

Conclusion

The efficacy and safety of triazoles are more favorable than D-AmB in the primary therapy of IA, with ISA being the optimal choice.

Systematic Review Registration

PROSPERO CRD42023407632.

Real-world study of isavuconazole adverse events based on pharmacovigilance spontaneous reporting systems

BACKGROUND

Isavuconazole is a novel second-generation triazole antifungal agent.We conducted a retrospective investigation to analyze the occurrence of adverse events (AEs) associated with isavuconazole in real-world clinical use by data-mining self-reporting databases, aiming to provide comprehensive data for its safe and effective clinical application.

RESEARCH DESIGN AND METHODS

All data obtained from the VigiBase, the EudraVigilance and the FAERS database. In the FAERS database, data mining algorithms, including reporting odds ratio (ROR) and proportional reporting ratio (PRR), were utilized to detect adverse event (AE) signals.

RESULTS

A total of 4,105 AE reports related to isavuconazole were retrieved from these databases. The highest proportion of AE reports was observed in individuals aged between 18-64 years old. The general disorders and administration site conditions system organ class accounted for the largest number of reported cases. The system organ classes with most signals and reports included general disorders and administration site conditions, blood and lymphatic system disorders as well as investigations related to hepatobiliary disorders. Notably high ROR and PRR values were observed for AE signals associated with hepatobiliary disorders.

CONCLUSION

Isavuconazole has fewer interactions and less liver, kidney and cardiac toxicity than other triazole antibiotics. The identification of novel AEs necessitates meticulous attention and further investigation and analysis.

Idiopathic aplastic anemia with concurrent complications of colonic perforation and mucormycosis: Case report

We report a case of a 72-year-old female who presented with fever, abdominal pain, and diarrhea accompanied by leukopenia, anemia, and thrombocytopenia. The diagnosis of acute aplastic anemia was confirmed through bone marrow aspiration. Treatment included glucocorticoids, immunoglobulin therapy, and plasma exchange. Subsequently, the patient developed gastrointestinal bleeding and abdominal Computed Tomography (CT) revealed perforation of the transverse colon. Pathological examination of surgically removed diseased tissue confirmed mucor infection. Despite receiving antifungal therapy with amphotericin B, the patient's condition deteriorated due to the sepsis progression. Mucor infection in immunocompromised patients should be vigilant, and early diagnosis may help improve prognosis.

Utility of Itraconazole in Combination with Liposomal Amphotericin B in Rhizopus oryzae Associated Mucormycosis-An Exploratory Study

BACKGROUND

During the COVID-19 pandemic-associated mucor epidemic, acute antifungal drug shortage necessitated the exploration of other antifungals based on culture sensitivity. Itraconazole is a cheap, safe, and effective antifungal in sensitive cases.

METHODOLOGY

We enrolled itraconazole-sensitive COVID-19-associated mucormycosis during the mucormycosis pandemic. After the intensive phase course of liposomal amphotericin B, Itraconazole was offered in susceptible cases during the maintenance phase along with standard of care. These patients were clinically and radiologically followed for 6 months.

RESULTS

We enrolled 14 patients (Male: Female-11:3) of Rhino-orbito-cerebral mucormycosis (ROCM) which included 12 diabetics. All patients had facial swelling, orbital swelling, visual impairment, and headache. MRI showed involvement of bilateral sinus (10/14), orbital extension (13/14), cavernous sinus (5/14), cerebral part of the internal carotid artery (3/14), and brain infarcts (4/14). All 14 patients showed sensitivity to Itraconazole with 12 having minimum inhibitory concentration (MIC) ≤ 1 μg/ml and 2 having MIC ≤ 2 μg/ml. Follow-up at 6 months showed clinical improvement in the majority (11/14) and radiological improvement in six out of seven scanned patients.

CONCLUSION

Our study shows the potential therapeutic role of oral Itraconazole in ROCM.

Biowaiver Monograph for Immediate-Release Solid Oral Dosage Forms: Isavuconazonium Sulfate

A Biopharmaceutics Classification System (BCS)-based biowaiver monograph is presented for isavuconazonium sulfate. A BCS-based biowaiver is a regulatory option to substitute appropriate in vitro data for in vivo bioequivalence studies. Isavuconazonium sulfate is the prodrug of isavuconazole, a broad-spectrum azole antifungal indicated for invasive fungal infections. While the prodrug can be classified as a BCS Class III drug with high solubility but low permeability, the parent drug can be classified as a BCS Class II drug with low solubility but high permeability. Interestingly, the in vivo behavior of both is additive and leads isavuconazonium sulfate to act like a BCS class I drug substance after oral administration. In this work, experimental solubility and dissolution data were evaluated and compared with available literature data to investigate whether it is feasible to approve immediate release solid oral dosage forms containing isavuconazonium sulfate according to official guidance from the FDA, EMA and/or ICH. The risks associated with waiving a prodrug according to the BCS-based biowaiver guidelines are reviewed and discussed, noting that current regulations are quite restrictive on this point. Further, results show high solubility but instability of isavuconazonium sulfate in aqueous media. Although experiments on the dissolution of the capsule contents confirmed 'very rapid' dissolution of the active pharmaceutical ingredient (API) isavuconazonium sulfate, its release from the commercial marketed capsule formulation Cresemba is limited by the choice of capsule shell material, providing an additional impediment to approval of generic versions via the BCS-Biowaiver approach.

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.

The Fragile Patient: Considerations in the Management of Invasive Mould Infections (IMIs) in India

Invasive mould infections (IMIs), which are mostly caused by Aspergillus spp. and Mucormycetes, are opportunistic infections that impose a substantial threat to patients who are considered to be 'fragile'. There is no fixed definition for fragile patients; however, patients with cancer or acquired immunodeficiency syndrome (AIDS), patients who have undergone organ transplants, and patients being treated in the intensive care units (ICUs) were considered fragile. Management of IMIs in fragile patients is challenging, owing to their compromised immune status. The diagnostic challenges associated with IMIs due to insufficient sensitivity and specificity of the current diagnostic tests lead to delayed treatment. A widening demographic of at-risk patients and a broadening spectrum of pathogenic fungi have added to the challenges to ascertain a definite diagnosis. A recent surge of mucormycosis associated with SARS-CoV-2 infections and the resultant steroid usage has been reported. Liposomal amphotericin B (L-AmB) is the mainstay for treating mucormycosis while voriconazole has displaced amphotericin B as the mainstay for treating Aspergillus infection due to its better response, improved survival, and fewer severe side effects. The selection of antifungal treatment has to be subjected to more scrutiny in fragile patients owing to their comorbidities, organ impairment, and multiple ongoing treatment modalities. Isavuconazole has been documented to have a better safety profile, stable pharmacokinetics, fewer drug-drug interactions, and a broad spectrum of coverage. Isavuconazole has thus found its place in the recommendations and can be considered a suitable option for treating fragile patients with IMIs. In this review, the authors have critically appraised the challenges in ascertaining an accurate diagnosis and current management considerations and suggested an evidence-based approach to managing IMIs in fragile patients.

Successful and Safe Real-Time TDM-Guided Treatment of Invasive Pulmonary and Cerebral Aspergillosis Using Low-Dose Isavuconazole in a Patient with Primary Biliary Cirrhosis: Grand Round/A Case Study

BACKGROUND

The authors present a case of a 67-year-old woman with primary biliary cirrhosis (Child-Pugh class B) who was treated with isavuconazole for invasive pulmonary and cerebral aspergillosis. Isavuconazole treatment was initiated with the standard maintenance dose of 200 mg daily. Therapeutic drug monitoring (TDM) was performed to target trough concentrations within the desired range of 1.0-5.13 mg/L.

METHODS

Real-time TDM and pharmacokinetic analyses were used to determine the dose adjustments. Liver transaminases (alanine aminotransferase and gamma-glutamyl transferase) were assessed to monitor hepatotoxicity.

RESULTS

The trough plasma levels gradually increased over time up to 17.8 mg/L. TDM-guided clinical pharmacological advice was helpful to initially reduce the dose, then to temporarily suspend drug administration, and finally to calculate the correct dose that allowed for long-term treatment up to day 258. No major signs and/or symptoms of drug-related toxicity occurred, apart from a transient increase in gamma-glutamyl transferases that normalized after the drop in isavuconazole trough levels within the desired range.

CONCLUSIONS

TDM-guided clinical pharmacological advice was essential for the successful and safe management of isavuconazole treatment in this patient with moderate liver dysfunction.

Target- and prodrug-based design for fungal diseases and cancer-associated fungal infections

Invasive fungal infections (IFIs) are emerging as a serious threat to public health and are associated with high incidence and mortality. IFIs also represent a frequent complication in patients with cancer who are undergoing chemotherapy. However, effective and safe antifungal agents remain limited, and the development of severe drug resistance further undermines the efficacy of antifungal therapy. Therefore, there is an urgent need for novel antifungal agents to treat life-threatening fungal diseases, especially those with new mode of action, favorable pharmacokinetic profiles, and anti-resistance activity. In this review, we summarize new antifungal targets and target-based inhibitor design, with a focus on their antifungal activity, selectivity, and mechanism. We also illustrate the prodrug design strategy used to improve the physicochemical and pharmacokinetic profiles of antifungal agents. Dual-targeting antifungal agents offer a new strategy for the treatment of resistant infections and cancer-associated fungal infections.

Clinical research advances of isavuconazole in the treatment of invasive fungal diseases

Purpose

Invasive fungal diseases (IFD) are a major global public health concern. The incidence of IFD has increased the demand for antifungal agents. Isavuconazole (ISA) is a new triazole antifungal agent that has shown promising efficacy in the prophylaxis and treatment of invasive fungal diseases. The aim of this review is to summarize the recent real-world experiences of using ISA for the treatment and prevention of IFD.

Methods

We performed a comprehensive literature search of the MEDLINE, PubMed, Embase, and Cochrane databases for clinical applications of ISA in the real world. Tables and reference lists are presented for this systematic review.

Results

IFD poses a major threat to public health and causes high mortality rates. ISA may provide a good treatment. For example, the efficacy of ISA in the treatment of invasive aspergillosis (IA) is comparable to that of voriconazole, and its efficacy in the treatment of invasive mucormycosis (IM) is similar to that of liposomal amphotericin B (L-AmB); therefore, ISA is recommended as the first-line treatment for IA and IM. ISA can also achieve good efficacy in the treatment of invasive candidiasis (IC) and can be used as an alternative to de-escalation therapy after first-line drug therapy. In addition, most studies have shown the efficacy and safety of ISA for the prophylaxis of IFD.

Conclusion

Taken together, ISA are expected to become a new choice for the treatment and prevention of IFD because of their good tolerability, high bioavailability, and few drug interactions.

COVID-19-Associated Pulmonary Mucormycosis

COVID-19-associated mucormycosis (CAM) emerged as an epidemic in certain parts of the world amidst the global COVID-19 pandemic. While rhino–orbital mucormycosis was well reported during the pandemic, in the absence of routine diagnostic facilities including lower airway sampling, pulmonary mucormycosis was probably under-recognized. In this review, we have focused on the epidemiology and management of COVID-19-associated pulmonary mucormycosis (CAPM). CAPM is a deadly disease and mortality can be as high as 80% in the absence of early clinical suspicion and treatment. While histopathological examination of tissue for angio-invasion and cultures have remained gold standard for diagnosis, there is an increasing interest in molecular and serological methods to facilitate diagnosis in critically ill patients and often, immune-suppressed hosts who cannot readily undergo invasive sampling. Combined medical and surgical treatment offers more promise than standalone medical therapy. Maintaining adequate glycemic control and prudent use of steroids which can be a double-edged sword in COVID-19 patients are the key preventative measures. We would like to emphasize the urgent need for the development and validation of reliable biomarkers and molecular diagnostics to facilitate early diagnosis.

Invasive Fungal Rhinosinusitis Due to Co-infection with Mucormycosis and Exserohilum rostratum in a Patient with Acute Lymphoblastic Leukemia

Invasive fungal infections remain an important cause of complication and morbidity in the management of acute leukemias. Here we report the case of a 27-year-old patient from French Polynesia who was diagnosed with Philadelphia chromosome-negative B-cell acute lymphoblastic leukemia. After induction chemotherapy, she developed rhinosinusitis with extensive bone lysis. The context and clinical presentation quickly made us suspect an invasive mucormycosis infection. However, a multidisciplinary investigation including mass spectrometry techniques also revealed the presence of Exserohilum rostratum, a pathogen member of the genus Exserohilum that is ubiquitous in tropical and subtropical regions but rarely implicated in invasive sinusitis. Antifungal treatment combined with an early surgical approach resulted in a favorable clinical response.

Mucormycosis: risk factors, diagnosis, treatments, and challenges during COVID-19 pandemic

Mucormycosis is a deadly opportunistic disease caused by a group of fungus named mucormycetes. Fungal spores are normally present in the environment and the immune system of the body prevents them from causing disease in a healthy immunocompetent individual. But when the defense mechanism of the body is compromised such as in the patients of diabetes mellites, neustropenia, organ transplantation recipients, and other immune-compromised states, these fungal spores invade our defense mechanism easily causing a severe systemic infection with approximately 45-80% of case fatality. In the present scenario, during the COVID-19 pandemic, patients are on immunosuppressive drugs, glucocorticoids, thus are at high risk of mucormycosis. Patients with diabetes mellitus are further getting a high chance of infection. Usually, the spores gain entry through our respiratory tract affecting the lungs and paranasal sinuses. Besides, they can also enter through damage into the skin or through the gastrointestinal route. This review article presents the current statistics, the causes of this infection in the human body, and its diagnosis with available recent therapies through recent databases collected from several clinics and agencies. The diagnosis and identification of the infection were made possible through various latest medical techniques such as computed tomography scans, direct microscopic observations, MALDI-TOF mass spectrometry, serology, molecular assay, and histopathology. Mucormycosis is so uncommon, no randomized controlled treatment studies have been conducted. The newer triazoles, posaconazole (POSA) and isavuconazole (ISAV) (the active component of the prodrug isavuconazonium sulfate) may be beneficial in patients who are refractory to or intolerant of Liposomal Amphotericin B. but due to lack of early diagnosis and aggressive surgical debridement or excision, the mortality rate remains high. In the course of COVID-19 treatments, there must be more vigilance and alertness are required from clinicians to evaluate these invasive fungal infections.

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.

Coexistence of Mucormycosis and Granulomatosis With Polyangiitis: A Diagnostic and Therapeutic Challenge

Mucormycosis is a destructive, necrotizing, and potentially fatal fungal disease that usually affects immunocompromised or diabetic patients. Granulomatosis with polyangiitis (GPA), previously known as Wegener’s granulomatosis is a rare, aseptic necrotizing, granulomatous vasculitis affecting small- to medium-sized vessels, resulting in systemic manifestations. Here, we present a case of a 46-year-old gentleman with overlapping features of mucormycosis and GPA, that was successfully treated with isavuconazole monotherapy.

Isavuconazole Treatment for Invasive Fungal Infections in Pediatric Patients

This work’s objective was to evaluate the safety of isavuconazole (ISA) as a treatment or prophylaxis for invasive fungal infections (IFIs) in immunocompromised children. IFI was reported as proven or probable according to international definitions. Therapeutic drug monitoring was performed using mass tandem spectrometry to quantify trough plasma concentrations. Targeted ISA levels were 2−4 mg/L, as reported in adult series. Nine patients received ISA as a curative treatment, and six received ISA as prophylaxis. IFIs were proven in four cases and probable in five. The median ISA trough plasma concentration in curative use was 3.19 mg/L [0.88;5.00], and it was 2.94 mg/L [2.77;3.29] in the prophylactic use. The median durations of treatment were 81 days [15;276] and 95 days [15;253], respectively. Three patients had elevated aspartate aminotransferase and alanine aminotransferase, and three patients had elevated creatinine serum. The IFI response was satisfactory in all cases at day 90. No side effects were reported. No patients developed an IFI. Our data underline the safety of an ISA 100 mg dosing regimen in children of <30 kg, which we recommend in this fragile population. We suggest that ISA plasma levels are monitored 10 days after ISA initiation and then every two weeks, alongside guided therapeutic drug monitoring (TDM) administration.

Antifungal Drugs TDM: Trends and Update

PURPOSE

The increasing burden of invasive fungal infections results in growing challenges to antifungal (AF) therapeutic drug monitoring (TDM). This review aims to provide an overview of recent advances in AF TDM.

METHODS

We conducted a PubMed search for articles during 2016-2020 using "TDM" or "pharmacokinetics" or "drug-drug-interaction" with "antifungal," consolidated for each AF. Selection was limited to English language articles with human data on drug exposure.

RESULTS

More than 1000 articles matched the search terms. We selected 566 publications. The latest findings tend to confirm previous observations in real-life clinical settings. The pharmacokinetic variability related to special populations is not specific but must be considered. AF benefit-to-risk ratio, drug-drug interaction (DDI) profiles, and minimal inhibitory concentrations for pathogens must be known to manage at-risk situations and patients. Itraconazole has replaced ketoconazole in healthy volunteers DDI studies. Physiologically based pharmacokinetic modeling is widely used to assess metabolic azole DDI. AF prophylactic use was studied more for Aspergillus spp. and Mucorales in oncohematology and solid organ transplantation than for Candida (already studied). Emergence of central nervous system infection and severe infections in immunocompetent individuals both merit special attention. TDM is more challenging for azoles than amphotericin B and echinocandins. Fewer TDM requirements exist for fluconazole and isavuconazole (ISZ); however, ISZ is frequently used in clinical situations in which TDM is recommended. Voriconazole remains the most challenging of the AF, with toxicity limiting high-dose treatments. Moreover, alternative treatments (posaconazole tablets, ISZ) are now available.

CONCLUSIONS

TDM seems to be crucial for curative and/or long-term maintenance treatment in highly variable patients. TDM poses fewer cost issues than the drugs themselves or subsequent treatment issues. The integration of clinical pharmacology into multidisciplinary management is now increasingly seen as a part of patient care.

Real-World Use of Isavuconazole as Primary Therapy for Invasive Fungal Infections in High-Risk Patients with Hematologic Malignancy or Stem Cell Transplant

(1) Introduction: Invasive fungal infections (IFIs) are a major cause of morbidity and mortality among immunocompromised patients with hematologic malignancies (HM) and stem cell transplants (SCT). Isavuconazole was approved by FDA as a primary therapy for Invasive Aspergillosis (IA) and Mucormycosis. The aim of this study is to look at the real-world use of Isavuconazole in patients with HM and evaluate their clinical outcomes and safety. (2) Methods: We conducted a retrospective study of HM patients at MD Anderson Cancer Center who had definite, probable or possible mold infections between 1 April 2016 and 31 January 2020 and were treated with Isavuconazole for a period of at least 7 days. Clinical and radiological findings were assessed at baseline and at 6 and 12 weeks of follow up. (3) Results: We included 200 HM patients with IFIs that were classified as definite (11), probable (63) and possible (126). Aspergillus spp was the most commonly isolated pathogen. The majority of patients (59%) received prophylaxis with anti-mold therapy and Isavuconazole was used as a primary therapy in 43% of patients, and as salvage therapy in 58%. The switch to Isavuconazole was driven by the failure of the primary therapy in 66% of the cases and by adverse effects in 29%. Isavuconazole was used as monotherapy in 30% of the cases and in combination in 70%. Adverse events possibly related to Isavuconazole were reported in eight patients (4%) leading to drug discontinuation. Moreover, a favorable response with Isavuconazole was observed in 40% at 6 weeks and in 60% at 12 weeks. There was no significant difference between isavuconazole monotherapy and combination therapy (p = 0.16 at 6 weeks and p = 0.06 at 12 weeks). Finally, there was no significant difference in outcome when Isavuconazole was used after failure of other anti-mold prophylaxis or treatment versus when used de novo as an anti-mold therapy (p = 0.68 at 6 weeks and p = 0.25 at 12 weeks). (4) Conclusions: Whether used as first-line therapy or after the failure of other azole and non-azole prophylaxis or therapies, isavuconazole seems to have a promising clinical response and a good safety profile as an antifungal therapy in high-risk cancer patients with hematologic malignancies. Moreover, combination therapy did not improve the outcome compared to Isavuconazole therapy.

The Past, Present and Future of COVID-19 Associated Mucormycosis: A Rapid Review

Coronavirus disease 2019 (COVID-19) is caused by SARS-CoV-2, which is known for the multiple mutations and forms that have rapidly spread across the world. With the imminent challenges faced by low- and middle-income countries in curbing the public health fallbacks due to limited resources, mucormycosis emerged as a fungal infection associated with high mortality. In this rapid review, we explored MEDLINE, Cochrane, Web of Science, WHO Global Database, and the search engine—Google Scholar for articles listed until July 2021 and presented a narrative synthesis of findings from 39 articles. The epidemiology, causative factors, incidence parameters, pharmacological treatment, and recommendations for low- and middle-income countries are enlisted. This study concludes that a majority of the globally reported COVID-19 associated mucormycosis cases stemmed from India. Individuals receiving systemic corticosteroids or who have a history of diabetes mellitus are more prone to contracting the disease. Public health authorities in LMIC are recommended to strengthen antifungal therapies for COVID-19 associated mucormycosis and to strategize reduction in diabetes mellitus prevalence.

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.

Population Pharmacokinetics and Pharmacodynamic Target Attainment of Isavuconazole against Aspergillus fumigatus and Aspergillus flavus in Adult Patients with Invasive Fungal Diseases: Should Therapeutic Drug Monitoring for Isavuconazole Be Considered as Mandatory as for the Other Mold-Active Azoles?

Isavuconazole is a newer broad-spectrum triazole approved for the treatment of invasive fungal disease. The objective of this study was to conduct a population pharmacokinetic and pharmacodynamic analysis of isavuconazole in a retrospective cohort of hospitalized patients. A nonlinear mixed-effect approach with Monte Carlo simulations was conducted to assess the probability of target attainment (PTA) of an area under the concentration–time curve (AUC_{24 h})/minimum inhibitory concentration (MIC) ratio of 33.4 (defined as efficacy threshold against A. fumigatus and A. flavus) associated with a maintenance dose (MD) of 100, 200 and 300 mg daily after loading. The cumulative fraction of response (CFR) against the EUCAST MIC distributions of A. fumigatus and A. flavus was calculated as well. The proportion of trough concentrations (C_trough) exceeding a defined threshold of toxicity (>5.13 mg/L) was estimated. A total of 50 patients, with a median age of 61.5 years, provided 199 plasma isavuconazole concentrations. Invasive pulmonary aspergillosis was the prevalent type of infection and accounted for 80% (40/50) of cases. No clinical covariates were retained by the model. With the standard MD of 200 mg daily, CFRs were always ≥90% during the first two months of treatment. The risk of C_trough < 1.0 mg/L was around 1%, and that of C_trough > 5.13 mg/L was 27.7 and 39.2% at 28 and 60 days, respectively, due to isavuconazole accumulation over time. Our findings suggest that TDM for isavuconazole should not be considered as mandatory as for the other mold-active azoles voriconazole and posaconazole.

The Overview on the Pharmacokinetic and Pharmacodynamic Interactions of Triazoles

Second generation triazoles are widely used as first-line drugs for the treatment of invasive fungal infections, including aspergillosis and candidiasis. This class, along with itraconazole, voriconazole, posaconazole, and isavuconazole, is characterized by a broad range of activity, however, individual drugs vary considerably in safety, tolerability, pharmacokinetics profiles, and interactions with concomitant medications. The interaction may be encountered on the absorption, distribution, metabolism, and elimination (ADME) step. All triazoles as inhibitors or substrates of CYP isoenzymes can often interact with many drugs, which may result in the change of the activity of the drug and cause serious side effects. Drugs of this class should be used with caution with other agents, and an understanding of their pharmacokinetic profile, safety, and drug-drug interaction profiles is important to provide effective antifungal therapy. The manuscript reviews significant drug interactions of azoles with other medications, as well as with food. The PubMed and Google Scholar bases were searched to collect the literature data. The interactions with anticonvulsants, antibiotics, statins, kinase inhibitors, proton pump inhibitors, non-nucleoside reverse transcriptase inhibitors, opioid analgesics, benzodiazepines, cardiac glycosides, nonsteroidal anti-inflammatory drugs, immunosuppressants, antipsychotics, corticosteroids, biguanides, and anticoagulants are presented. We also paid attention to possible interactions with drugs during experimental therapies for the treatment of COVID-19.

Pharmacological management of antifungal agents in pulmonary aspergillosis: an updated review

INTRODUCTION

Aspergillus may cause different types of lung infections: invasive, chronic pulmonary or allergic bronchopulmonary aspergillosis. Pharmacological management with antifungals poses as a challenge. Patients diagnosed with pulmonary aspergillosis are complex, as well as the problems associated with antifungal agents.

AREAS COVERED

This article reviews the pharmacology of antifungal agents in development and currently used to treat pulmonary aspergillosis, including the mechanisms of action, pharmacokinetics, pharmacodynamics, dosing, therapeutic drug monitoring and safety. Recommendations to manage situations that arise in daily clinical practice are provided. A literature search of PubMed was conducted on November 15^th, 2020 and updated on March 30^th, 2021.

EXPERT OPINION

Recent and relevant developments in the treatment of pulmonary aspergillosis have taken place. Novel antifungals with new mechanisms of action that extend antifungal spectrum and improve pharmacokinetic-related aspects, drug-drug interactions and safety are under current study. For those antifungals already marketed, new data related to pharmacokinetics, pharmacodynamics, dose adjustments in special situations, therapeutic drug monitoring and safety are available. To maximize efficacy and reduce the risk of associated toxicities, it is essential to choose the most appropriate antifungal; optimize its dose, interval, route of administration and length of treatment; and prevent side effects.

Clinical and microbiological features and outcomes of mucormycosis in critically ill patients

INTRODUCTION

Mucormycosis is a rare invasive fungal infection with high mortality in patients with severe underlying predisposing factors causing immunosuppression. The exact incidence of mucormycosis and the optimal therapeutic approach is difficult to determine, especially in severe cases, due to the rarity of the disease. The new second-generation triazole isavuconazole provides an alternative treatment option which may represent a potential benefit in severe cases.

MATERIALS AND METHODS

A retrospective case series was conducted of patients with a positive laboratory culture for Mucorales and consistent clinical findings who required intensive care treatment. Patient characteristics including demographics, comorbidities, microbiological analysis, specific antifungal therapy and clinical outcome were analysed.

RESULTS

Fifteen critically ill patients with Mucorales detected between 2016 and 2019 were included in this study; the crude mortality rate was 100%. At the time of diagnosis of mucormycosis, 80% of subjects had relevant medical immunosuppression and 53.3% of subjects had neutropenia. Manifestation of mucormycosis was pulmonary in 53.3% of subjects, rhino-orbital in 20% of subjects and disseminated in 26.7% of subjects. Notably, 40% of all patients had received antifungal prophylaxis prior to mucormycosis, mainly with posaconazole due to underlying haematological malignancy, thus possibly representing break-through infections. Antifungal therapy for invasive mucormycosis was administered in 80% of subjects for a median duration of 16 days.

CONCLUSION

In this retrospective cohort analysis of intensive care patients, the prognosis of mucormycosis was extremely poor. An aggressive strategy for diagnosis and treatment is essential for intensive care patients with mucormycosis. There is a need for further research to determine if combination therapy in higher dosages or prompt surgery is beneficial in severe critically ill patients.

Molecular and genetic basis of azole antifungal resistance in the opportunistic pathogenic fungus Candida albicans

Candida albicans is an opportunistic yeast and the major human fungal pathogen in the USA, as well as in many other regions of the world. Infections with C. albicans can range from superficial mucosal and dermatological infections to life-threatening infections of the bloodstream and vital organs. The azole antifungals remain an important mainstay treatment of candidiasis and therefore the investigation and understanding of the evolution, frequency and mechanisms of azole resistance are vital to improving treatment strategies against this organism. Here the organism C. albicans and the genetic changes and molecular bases underlying the currently known resistance mechanisms to the azole antifungal class are reviewed, including up-regulated expression of efflux pumps, changes in the expression and amino acid composition of the azole target Erg11 and alterations to the organism's typical sterol biosynthesis pathways. Additionally, we update what is known about activating mutations in the zinc cluster transcription factor (ZCF) genes regulating many of these resistance mechanisms and review azole import as a potential contributor to azole resistance. Lastly, investigations of azole tolerance in C. albicans and its implicated clinical significance are reviewed.

Exploring the solid form landscape of the antifungal drug isavuconazole: crystal structure analysis, phase transformation behavior and dissolution performance

Phase transformation of ISV solid forms during dissolution.

Isolated cerebral mucormycosis associated with intravenous drug use

We present an uncommon case of isolated basal ganglia mucormycosis in a patient without any known cause of immunosuppression, but with a history of drug injection. The patient presented a good clinical and radiological response to antifungal treatment without aggressive surgical debridement (liposomal amphotericin B combined with isavuconazole for 4 weeks followed by isavuconazole as maintenance therapy for 10 months).

Tailor-Made Amino Acids and Fluorinated Motifs as Prominent Traits in Modern Pharmaceuticals

Structural analysis of modern pharmaceutical practices allows for the identification of two rapidly growing trends: the introduction of tailor-made amino acids and the exploitation of fluorinated motifs. Curiously, the former represents one of the most ubiquitous classes of naturally occurring compounds, whereas the latter is the most xenobiotic and comprised virtually entirely of man-made derivatives. Herein, 39 selected compounds, featuring both of these traits in the same molecule, are profiled. The total synthesis, source of the corresponding amino acids and fluorinated residues, and medicinal chemistry aspects and biological properties of the molecules are discussed.

A Case Series and Literature Review of Isavuconazole Use in Pediatric Patients with Hemato-oncologic Diseases and Hematopoietic Stem Cell Transplantation

We analyzed the use of isavuconazole (ISA) as treatment or prophylaxis for invasive fungal disease (IFD) in children with hemato-oncologic diseases. A multicentric retrospective analysis was performed among centers belonging to the Italian Association for Pediatric Hematology and Oncology (AIEOP). Pharmacokinetic (PK) monitoring was applied by a high-performance liquid chromatography-tandem mass spectrometry (HLPC-MS/MS) assay. Twenty-nine patients were studied: 10 during chemotherapy and 19 after allogeneic hematopoietic stem cell transplantation (HSCT). The patients consisted of 20 males and 9 females with a median age of 14.5 years (age range, 3 to 18 years) and a median body weight of 47 kg (body weight range, 15 to 80 kg). ISA was used as prophylaxis in 5 patients and as treatment in 24 cases (20 after therapeutic failure, 4 as first-line therapy). According to European Organization for Research and Treatment of Cancer (EORTC) criteria, we registered 5 patients with proven IFD, 9 patients with probable IFD, and 10 patients with possible IFD. Patients with a body weight of <30 kg received half the ISA dose; the others received ISA on the adult schedule (a 200-mg loading dose every 8 h on days 1 and 2 and a 200-mg/day maintenance dose); for all but 10 patients, the route of administration switched from the intravenous route to the oral route during treatment. ISA was administered for a median of 75.5 days (range, 6 to 523 days). The overall response rate was 70.8%; 12 patients with IFD achieved complete remission, 5 achieved partial remission, 5 achieved progression, and 3 achieved stable IFD. No breakthrough infections were registered. PK monitoring of 17 patients revealed a median ISA steady-state trough concentration of 4.91 mg/liter (range, 2.15 to 8.54 mg/liter) and a concentration/dose (in kilograms) ratio of 1.13 (range, 0.47 to 3.42). Determination of the 12-h PK profile was performed in 6 cases. The median area under the concentration-time curve from 0 to 12 h was 153.16 mg·h/liter (range, 86.31 to 169.45 mg·h/liter). Common Terminology Criteria for Adverse Events grade 1 to 3 toxicity (increased transaminase and/or creatinine levels) was observed in 6 patients, with no drug-drug interactions being seen in patients receiving immunosuppressants. Isavuconazole may be useful and safe in children with hemato-oncologic diseases, even in the HSCT setting. Prospective studies are warranted.

A Single-Center, Open-Label Trial of Isavuconazole Prophylaxis against Invasive Fungal Infection in Patients Undergoing Allogeneic Hematopoietic Cell Transplantation

Isavuconazole is a broad-spectrum triazole approved for treatment of invasive fungal infections (IFIs). In this open-label, single-arm study, we evaluated isavuconazole for antifungal prophylaxis after allogeneic hematopoietic cell transplantation (HCT). Adult patients admitted for first HCT received micafungin 150 mg i.v. daily from admission through day +7 (D+7) post-transplantation (±2 days) followed by isavuconazole prophylaxis (i.v./p.o. 372 mg every 8 hours for 6 doses and then 372 mg daily) through maximum D+98 post-HCT. Patients were followed through D+182. The primary endpoint was prophylaxis failure, defined as discontinuation of prophylaxis for proven/probable IFI; systemic antifungal therapy for >14 days for suspected IFI; toxicity leading to discontinuation; or an adverse event. Between June 2017 and October 2018, 99 patients were enrolled in the study, of whom 95 were included in our analysis. The median patient age was 57 years (interquartile range [IQR], 50 to 66 years). Sixty-four (67%) patients received peripheral blood, 17(18%) received bone marrow, and 14 (15%) received a cord blood allograft for acute leukemia (55%), lymphoma (17%), myelodysplastic syndrome (16%), or another hematologic disease (14%). One-third (n = 31; 33%) of patients underwent CD34⁺-selected HCT. Isavuconazole prophylaxis was given for a median of 90 days (IQR, 87 to 91 days). Ten patients (10.7%) met the primary endpoint. Candidemia occurred in 3 patients (3.1%), 1 of whom had grade III skin acute graft-versus-host disease (GVHD). Toxicity leading to discontinuation occurred in 7 patients (7.4%). The most common toxicity was liver function abnormalities in 5 patients, including grade 1 transaminitis in 2 patients and grade 3 hyperbilirubinemia in 3 patients. Four patients (4.2%) had early discontinuation of isavuconazole for reasons not meeting the primary study endpoint. Six patients died during the study period, including 3 during prophylaxis and 3 during follow-up. No deaths were attributed to isavuconazole. The majority (85%) of allogeneic HCT recipients completed isavuconazole prophylaxis according to protocol. The rate of breakthrough candidemia was 3.1%, and there were no invasive mold infections. Our data support the utility of isavuconazole for antifungal prophylaxis after HCT.

Clinical Pharmacokinetics of Second-Generation Triazoles for the Treatment of Invasive Aspergillosis and Candidiasis

Second-generation triazoles were developed in response to the quest for more efficacious and safer therapeutic options for the treatment of severe systemic aspergillosis and candidiasis. These agents include voriconazole, posaconazole, isavuconazole, and ravuconazole. The aim of this review was to present and compare the pharmacokinetic characteristics of second-generation triazoles for the treatment of invasive aspergillosis and candidiasis, emphasizing their clinical implications. The MEDLINE, Scopus, EBSCO, Google Scholar, and SCIndeks databases were searched using advanced search options, including the names of second-generation triazoles and pharmacokinetic terms as keywords. The intravenous administration of voriconazole, posaconazole, and isavuconazole results in stable pharmacokinetics of these drugs, with mostly predictable variations influenced by common and usually known factors in routine clinical settings. The high oral bioavailability of isavuconazole and, to some extent, voriconazole makes them suitable for intravenous-to-oral switch strategies. Except for intravenous voriconazole (due to the accumulation of the toxic vehicle hydroxypropyl betadex), dose reduction of second-generation triazoles is not needed in patients with renal failure; patients with hepatic insufficiency require dose reduction only in advanced disease stages. The introduction of therapeutic drug monitoring could aid attempts to optimize the blood concentrations of triazoles and other drugs that are known to or that possibly interact, thus increasing treatment efficacy and safety. There is a need for new studies that are designed to provide useful data on second-generation triazole pharmacokinetics, particularly in special circumstances such as central nervous system and ocular infections, infections in newborns and infants, and in subjects with genetic polymorphisms of metabolizing enzymes.

Isavuconazole and voriconazole for the treatment of chronic pulmonary aspergillosis: A retrospective comparison of rates of adverse events

BACKGROUND

Long-term oral triazole antifungal therapy is the cornerstone of management for patients with chronic pulmonary aspergillosis (CPA). Itraconazole is the first-line choice of treatment. Voriconazole, posaconazole or isavuconazole can be used as alternative treatments in case of resistance or intolerance. All of these can cause significant adverse drug reactions.

OBJECTIVES

To evaluate how CPA patients tolerate voriconazole and isavuconazole after prior triazole therapy.

METHODS

We performed a retrospective observational study at the UK National Aspergillosis Centre. Medical records for all consecutive CPA patients started on isavuconazole and voriconazole during an observation period of 12 and 6 months respectively were analysed.

RESULTS

During this study period, 20 patients were started on isavuconazole and 21 patients on voriconazole. Adverse events were seen in 18 of 21 (86%) the patients in the voriconazole group and 12 of 20 (60%) in the isavuconazole group (P = 0.02). For those who developed adverse events to these agents, the rates of discontinuation of therapy were comparable (ie 10/18 [56%], voriconazole vs 8/12 [67%], isavuconazole; P = 0.54). Five (25%) patients in the isavuconazole group who were intolerant to other triazoles tolerated the standard dose of isavuconazole.

CONCLUSIONS

Compared with isavuconazole, adverse events were significantly higher in CPA patients commenced on voriconazole. Isavuconazole may be an option for those patients who are intolerant to other triazoles.

[Invasive aspergillosis in solid organ transplantation]

Solid organ transplant (SOT) recipients have a high risk for developing invasive fungal infections (IFI). Treatment is difficult due to the interaction between the antifungal and immunosuppressant drugs, as well as the risk of hepatotoxicity and kidney failure associated with voriconazole and amphotericinB, respectively. Isavuconazole is a new antifungal triazole agent with excellent oral bioavailability, predictable and linear pharmacokinetics, good tolerance and low adverse effects. It has been approved for the treatment of invasive aspergillosis and mucormycosis. A review is presented of the reported experience in the use of isavuconazole in SOT. According to the published studies, isavuconazole has a significantly lower risk of interaction with tacrolimus, and is less hepatotoxic than voriconazole. Nevertheless, there is a significant variability between patients, and between each type of SOT. Isavuconazole reduces the side effects associated with the treatment of IFI in SOT. It would be of great interest the implementation of future clinical trials with isavuconazole for the treatment and/or prophylaxis of IFI in these patients.

Late-onset isavuconazole-induced liver injury

Antifungal agents account for approximately 3% of Drug-Induced Liver Injury (DILI) cases. Isavuconazole is a novel triazole, and experience with long-term use of it is lacking. We report a case of late-onset DILI occurring after 11 months of isavuconazole therapy in a 55-year old man of Angolan descent on long-term antifungal therapy for the management of chronic pulmonary aspergillosis complicating previously treated pulmonary tuberculosis. The DILI could be described as idiosyncratic as it was not associated with high isavuconazole serum levels and his liver function tests returned to normal following treatment discontinuation.

Mucormycosis in Children: Review and Recommendations for Management

Mucormycosis represents the third most common invasive fungal infection in children, and recent studies have suggested a rising incidence. Its case fatality rate is high, especially for neonates. Clinical presentation is influenced by underlying risk factors; associations with immunosuppression, neutropenia, diabetes, and prematurity have been described. It has been implicated in several hospital outbreaks. Diagnosis requires a high index of suspicion and evaluation with histopathology, culture, and, increasingly, molecular identification. Surgical debridement and antifungal therapies are the cornerstone for combatting invasive mucormycosis. However, the severity and relative rarity of this disease make comparative clinical trials for evaluating antifungal therapies in children difficult to conduct. Hence, therapeutic decisions are derived mainly from retrospective case series, in vitro data, and animal models. In this review, we summarize the literature on the epidemiology and diagnosis of this invasive fungal infection and provide suggestions on the management of mucormycosis in children.

In Vitro Combination of Isavuconazole with Echinocandins against Azole-Susceptible and -Resistant Aspergillus spp

In vitro combinations of isavuconazole with echinocandins were evaluated against 30 Aspergillus strains with a two-dimensional checkerboard microdilution method and an agar-based diffusion method. With the checkerboard method, the three combinations showed indifferent interactions for all strains. With the agar-based method, indifferent interactions were found for all strains for isavuconazole-micafungin and isavuconazole-anidulafungin. For the isavuconazole-caspofungin combination, indifference was found in 24/30 strains, synergism in 4/30 strains, and antagonism in 2/30 strains.

Meta-analysis of the safety of voriconazole in definitive, empirical, and prophylactic therapies for invasive fungal infections

Background

Voriconazole has been used in the treatment and prophylaxis of invasive fungal infections (IFIs) while its wide use was limited by some frequent adverse events, especially neurotoxicity, hepatotoxicity and even renal disruption. The aim of this study was to comprehensively compare voriconazole-induced toxicity, including tolerability, neurotoxicity, visual toxicity, hepatotoxicity and nephrotoxicity with the composite of other antifungals commonly used in clinic.

Methods

Bibliography databases were searched to select randomized controlled trials providing information about the incidence of toxicity referred above. A total of 4122 patients from 16 studies were included in the meta-analysis.

Results

Analysis of individual types of toxicity showed that there was a significant difference between voriconazole and the composite of other antifungal agents. The primary outcome, the tolerability of voriconazole was slightly inferior (OR = 1.71, 95% CI = 1.21–2.40, P = 0.002) and it is noteworthy that the probabilities of neurotoxicity and visual toxicity were around twice higher and six-fold for voriconazole compared with the counterpart (OR = 1.99, 95% CI = 1.05–3.75, P = 0.03 and OR = 6.50, 95% CI = 2.93–14.41, P < 0.00001, respectively). Hepatotoxicity was more common in voriconazole group (OR = 1.60, 95% CI = 1.17–2.19, P = 0.003) whereas its pooled risk of nephrotoxicity was about half of the composite of other five antifungal agents (OR = 0.46, 95% CI = 0.26–0.84, P = 0.01).

Conclusion

Our analysis has revealed differences in multiple types of toxicity induced by VRC versus other antifungals and quantified the corresponding pooled risks, which could provide an alternative for patients with a certain antifungal intolerance and help the clinician to select the optimal intervention.

Electronic supplementary material

The online version of this article (10.1186/s12879-017-2913-8) contains supplementary material, which is available to authorized users.

Two Phase 1, Open-Label, Mass Balance Studies to Determine the Pharmacokinetics of 14 C-Labeled Isavuconazonium Sulfate in Healthy Male Volunteers

Isavuconazonium sulfate is the water‐soluble prodrug of the active triazole isavuconazole. Two phase 1 studies were conducted to identify the metabolic profile and mass balance of isavuconazole and BAL8728 (inactive cleavage product). Seven subjects in study 1 (isavuconazole mass balance) received a single oral dose of [cyano‐¹⁴C]isavuconazonium sulfate corresponding to 200 mg isavuconazole. Six subjects in study 2 (BAL8728 mass balance) received a single intravenous dose of [pyridinylmethyl‐¹⁴C]isavuconazonium sulfate corresponding to 75 mg BAL8728. Pharmacokinetic parameters of radioactivity in whole blood and plasma and of isavuconazole and BAL8728 in plasma were assessed. Radioactivity ratio of blood/plasma, percentage of dose, and cumulative percentage of radioactive dose recovered in urine and feces for isavuconazole and BAL8728 were assessed. Metabolic profiling was carried out by high‐performance liquid chromatography and mass spectrometry. Mean plasma isavuconazole pharmacokinetic parameters included apparent clearance (2.3 ± 0.7 L/h), apparent volume of distribution (301.8 ± 105.7 L), and terminal elimination half‐life (99.9 ± 44.6 hours). In study 1, isavuconazole‐derived radioactivity was recovered approximately equally in urine and feces (46.1% and 45.5%, respectively). In study 2, BAL8728‐derived radioactivity was predominantly recovered in urine (96.0%). Isavuconazole (study 1) and M4 (cleavage metabolite of BAL8728; study 2) were the predominant circulating components of radioactivity in plasma.

Invasive Fungal Infections in the Intensive Care Unit

Patients in the intensive care unit are exposed to multiple stressors that predispose them to invasive fungal infections (IFIs), which carry high morbidity and mortality. Getting acquainted with the diagnostic methods and therapies is imperative for patient safety and for providing high-quality health care. This article focuses on the most frequent IFIs: invasive candidiasis and invasive aspergillosis.

Special considerations for the diagnosis and treatment of invasive pulmonary aspergillosis

INTRODUCTION

The diagnosis and treatment of invasive pulmonary aspergillosis (IPA) are ongoing challenges in clinical practice. While important advances have recently been made, including enhanced diagnostic modalities as well as novel therapeutic and prophylactic options, more effective options are urgently needed as the population of immunocompromised patients continues to expand. Areas covered: In this paper, we review novel approaches to diagnosis of IPA, including multiplex PCR, Matrix Assisted Laser Desorption/Ionization-Time of Flight Mass Spectrometry and provide a detailed review of the extended-spectrum triazole isavuconazole, which was approved in 2015 to treat IPA. Expert commentary: We explore burgeoning approaches to diagnosis, including the lateral flow assay, volatile organic compounds, and artificial olfactory technology, as well as novel antifungal agents to treat IPA such as SCY-078 and F901318.

Diagnosis, classification, and therapeutic interventions for sinopulmonary Aspergillosis

INTRODUCTION

Sinopulmonary aspergillosis represents a diverse collection of allergic, invasive, and chronic sinus and respiratory conditions. These diseases can affect patients with and without immune impairment and in some cases may be life-threatening. Areas covered: We review the diagnosis, classification, and therapeutic options available to treat sinopulmonary aspergillosis and look ahead to emerging diagnostic and therapeutic options that may soon play an important role in clinical practice. Expert commentary: Histopathology and tissue culture remain the gold standard for the diagnosis of invasive sinopulmonary aspergillosis, but several new molecular detection methods have recently emerged, including various PCR-based platforms, MALDI-TOF, and lateral flow assays. We examine these methodologies as well as the barriers associated with the standardization, validation, and implementation. We also explore the pipeline of antifungal agents in development to treat sinopulmonary aspergillosis.