Real‐world use—Isavuconazole at a large academic medical center

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.

Isavuconazole Versus Voriconazole as the First-line Therapy for Solid Organ Transplant Recipients With Invasive Aspergillosis: Comparative Analysis of 2 Multicenter Cohort Studies

BACKGROUND

Isavuconazole (ISA) and voriconazole (VORI) are recommended as the first-line treatment for invasive aspergillosis (IA). Despite theoretical advantages of ISA, both triazole agents have not been compared in solid organ transplant recipients.

METHODS

We performed a post hoc analysis of 2 retrospective multicenter cohorts of solid organ transplant recipients with invasive fungal disease (the SOTIS [Solid Organ Transplantation and ISavuconazole] and DiasperSOT [DIagnosis of ASPERgillosis in Solid Organ Transplantation] studies). We selected adult patients with proven/probable IA that were treated for ≥48 h with ISA (n = 57) or VORI (n = 77) as first-line therapy, either in monotherapy or combination regimen. The primary outcome was the rate of clinical response at 12 wk from the initiation of therapy. Secondary outcomes comprised 12-wk all-cause and IA-attributable mortality and the rates of treatment-emergent adverse events and premature treatment discontinuation.

RESULTS

Both groups were comparable in their demographics and major clinical and treatment-related variables. There were no differences in the rate of 12-wk clinical response between the ISA and VORI groups (59.6% versus 59.7%, respectively; odds ratio [OR], 0.99; 95% confidence interval [CI], 0.49-2.00). This result was confirmed after propensity score adjustment (OR, 0.81; 95% CI, 0.32-2.05) and matching (OR, 0.79; 95% CI, 0.31-2.04). All-cause and IA-attributable mortality were also similar. Patients in the ISA group were less likely to experience treatment-emergent adverse events (17.5% versus 37.7%; P = 0.011) and premature treatment discontinuation (8.8% versus 23.4%; P = 0.027).

CONCLUSIONS

Front-line treatment with ISA for posttransplant IA led to similar clinical outcomes than VORI, with better tolerability and higher treatment completion.

Pharmacological management of invasive mold infections in solid organ transplant recipients

INTRODUCTION

Solid organ transplant (SOT) recipients face an increased susceptibility to invasive fungal infection (IFI) due to filamentous fungi. Post-transplant invasive aspergillosis (IA) and mucormycosis are related to exceedingly high mortality rates and graft loss risk, and its management involve a unique range of clinical challenges.

AREAS COVERED

First, the current treatment recommendations for IA and mucormycosis among SOT recipients are critically reviewed, including the supporting evidence. Next, we discussed particular concerns in this patient population, such as drug-drug interactions (DDIs) between triazoles and post-transplant immunosuppression or treatment-related toxicity. The role for immunomodulatory and host-targeted therapies is also considered, as well as the theoretical impact of the intrinsic antifungal activity of calcineurin inhibitors. Finally, a personal opinion is made on future directions in the pharmacological approach to post-transplant IFI.

EXPERT OPINION

Despite relevant advances in the treatment of mold IFIs in the SOT setting, such as the incorporation of isavuconazole (with lower incidence of DDIs and better tolerability than voriconazole), there remains a large room for improvement in areas such as the position of combination therapy or the optimal strategy for the reduction of baseline immunosuppression. Importantly, future studies should define the specific contribution of newer antifungal agents and classes.

Breakthrough invasive fungal infections on isavuconazole prophylaxis in hematologic malignancy & hematopoietic stem cell transplant patients

BACKGROUND

Isavuconazole (ISA) is a newer antifungal used in patients with history of hematologic malignancies and hematopoietic transplant and cellular therapies (HM/TCT). Although it has a more favorable side-effect profile, breakthrough invasive fungal infections (bIFIs) while on ISA have been reported.

METHODS

In this single-center retrospective study evaluating HM/TCT patients who received prophylactic ISA for ≥7 days, we evaluated the incidence and potential risk factors for bIFIs.

RESULTS

We evaluated 106 patients who received prophylactic ISA. The patients were predominantly male (60.4%) with median age of 65 (range: 21-91) years. Acute myeloid leukemia (48/106, 45.3%) was the most common HM, with majority having relapsed and/or refractory disease (43/106, 40.6%) or receiving ongoing therapy (38/106, 35.8%). Nineteen patients (17.9%) developed bIFIs-nine proven [Fusarium (3), Candida (2), Mucorales plus Aspergillus (2), Mucorales (1), Colletotrichum (1)], four probable invasive pulmonary Aspergillus, and six possible infections. Twelve patients were neutropenic for a median of 28 (8-253) days prior to bIFI diagnosis. ISA levels checked within 7 days of bIFI diagnosis (median: 3.65 μg/mL) were comparable to industry-sponsored clinical trials. All-cause mortality among the bIFI cases was 47.4% (9/19).We also noted clinically significant cytomegalovirus co-infection in 5.3% (1/19). On univariate analysis, there were no significant differences in baseline comorbidities and potential risk factors between the two groups.

CONCLUSION

ISA prophylaxis was associated with a significant cumulative incidence of bIFIs. Despite the appealing side-effect and drug-interaction profile of ISA, clinicians must be vigilant about the potential risk for bIFIs.

Real-World, Multicenter Case Series of Patients Treated with Isavuconazole for Invasive Fungal Disease in China

BACKGROUND

The incidence of invasive fungal disease (IFD) has increased significantly, and IFD is a major cause of mortality among those with hematological malignancies. As a novel second-generation triazole antifungal drug offering both efficacy and safety, isavuconazole (ISA) is recommended by various guidelines internationally for the first-line treatment of invasive aspergillosis (IA) and invasive mucormycosis (IM) infecting adults. Given that it was only approved in China at the end of 2021, there is currently a lack of statistical data regarding its usage in the Chinese population. The primary objective of this report is to describe early experiences with ISA for the treatment of IFD.

METHODS

This was a real-world, multicenter, observational case series study conducted in China. It included patients from three centers who received ISA treatment from January 2022 to April 2023. A retrospective assessment on patient characteristics, variables related to ISA administration, the treatment response of IFD to ISA, and potential adverse events attributed to ISA was conducted.

RESULTS

A total of 40 patients met the inclusion criteria. Among them, 12 (30%) were diagnosed with aspergillosis, 2 (5%) were diagnosed with candidiasis, 12 (30%) were diagnosed with mucormycosis, and 14 cases did not present mycological evidence. The predominant site of infection was the lungs (36), followed by the blood stream (8), sinuses (4), and respiratory tract (2). The overall response rate was 75% (30 patients), with male patients having a higher clinical response than female patients (24/24 versus 6/16, p = 0.000) and autologous stem cell transplant patients having a higher clinical response than allogeneic stem cell transplant patients (6/6 versus 4/10, p = 0.027). During the observation period, four patients experienced adverse effects associated with ISA, but none of them discontinued the treatment.

CONCLUSIONS

Our findings suggest that ISA, a novel first-line treatment for IA and IM, is associated with a high clinical response rate, low incidence, and a low grade of adverse effects. Given the short time that ISA has been available in China, further research is needed to identify its efficacy and safety in the real world.

Observed isavuconazole exposure: 5-year experience of azole TDM from a Spanish reference laboratory

We aimed to assess patient exposure to isavuconazole (ISZ) from samples received in our laboratory for therapeutic antifungal monitoring. We used liquid chromatography coupled with ultraviolet (UV) absorbance detection adapted from a multiplex-validated method with photodiode array (PDA) detection to monitor the analytes. The latter device allows the characterization of the azoles UV spectra. The method was validated according to international guidelines for efficient ISZ monitoring. The assay exhibited linearity between 0.25 and 16 mg/l for ISZ. Accuracy and intra- and inter-day precision were within acceptable ranges, and the method was successfully applied to quantify azoles and major metabolites from clinical samples collected from treated patients. We focus on ISZ blood concentrations and compared them to those of voriconazole, posaconazole, and itraconazole for a period of 5 years (2017-2021). Median ISZ concentration was 2.92 mg/l (interquartile range 1.82-5.33 mg/l) with 89% of measurements classified as adequate exposure (> 1 mg/l). Additionally, 71% of samples reach concentration values > 2 mg/l. Different ISZ exposure between adults to children were found. In conclusion, ISZ achieves excellent blood concentrations compared to other azole drugs, they are almost identical to those previously described, they exceed the MICs of most fungi for which its use was recommended and they differ depending on the patient's age. The method we describe for antifungal monitoring is simple, robust, and efficient. It simultaneously analyzes azoles and metabolites, and can be used for tailored interventions, achieve exposures associated with therapeutic success, decrease treatment-related toxicity, and help prevent resistance emergence due to continuous azole sub-optimal concentrations.

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.

Efficacy and safety of Isavuconazole for the treatment of invasive Aspergillus infection - an update of the literature

INTRODUCTION

Invasive aspergillosis is associated with high morbidity and mortality in immunocompromised patients. It is now increasingly reported in critically ill patients, including those with respiratory viral infections, such as influenza and COVID-19. Antifungal management is challenging due to diagnostic delay, adverse drug reactions, drug-drug interactions, narrow therapeutic window, and the emergence of resistance. Isavuconazole is the most recent FDA approved azole for the treatment of invasive aspergillosis, with data continuing to accumulate.

AREAS COVERED

The authors review the safety and efficacy of isavuconazole in the management of invasive aspergillosis based on the currently available evidence. The authors also report on the structure, mechanism of action, pharmacokinetic properties, in vitro and in vivo studies as well as clinical safety and efficacy reports of isavuconazole since its FDA approval.

EXPERT OPINION

Isavuconazole is non-inferior to voriconazole and is a safe, effective, and better tolerated option for the treatment of invasive aspergillosis. It offers several advantages over other antifungal agents, including having a better adverse event profile with respect to hepatotoxicity, neuro-visual toxicity, QTc prolongation, as well as a stable pharmacokinetic profile obviating the need for therapeutic drug monitoring. Further studies are needed to evaluate its performance in prophylaxis against invasive aspergillosis as well as in the treatment of aspergillosis in critically ill patients without underlying cancer or transplant.

Efficacy and safety of isavuconazole compared with voriconazole as primary antifungal prophylaxis in allogeneic hematopoietic cell transplant recipients

Voriconazole is frequently discontinued prematurely as primary antifungal prophylaxis (AFP) in allogeneic hematopoietic cell transplant (HCT) recipients due to adverse events. Limited data exists for isavuconazole as AFP. We analyzed adult HCT recipients who received voriconazole or isavuconazole AFP to estimate rate of premature AFP discontinuation, identify risk factors for premature AFP discontinuation, and compare incidence of invasive fungal infection (IFI) and survival at day + 180 post-HCT between patients who received voriconazole/isavuconazole-AFP. This was a propensity score matched cohort analysis of 210 HCT-recipients who received voriconazole-AFP (9/1/2014-12/31/2016; voriconazole-cohort), and 95 HCT-recipients who received isavuconazole-AFP (5/1/2017-10/31/2018; isavuconazole-cohort). AFP discontinuation for any reason prior to completion was defined as "premature". Median (interquartile range, IQR) duration of AFP was longer in the isavuconazole-cohort (94 days, 87-100) vs. the voriconazole-cohort (76 days, 23-94; P-value < 0.0001). Premature AFP discontinuation was more frequent in the voriconazole-cohort (92/210, 43.8%) vs. the isavuconazole-cohort (14/95, 14.7%; P-value < 0.0001). The most common reason for premature discontinuation was biochemical hepatotoxicity (voriconazole-cohort: 48/210, 22.8% vs. isavuconazole-cohort: 5/95, 5.26%; P-value = 0.0002). Transaminase values between baseline and end-of-treatment (EOT) and up to 14 days post-EOT significantly increased in the voriconazole-cohort, but remained unchanged in the isavuconazole-cohort. The incidence of IFI at day + 180 was 2.9% (6/210) and 3.2% (3/95) in the voriconazole-cohort and isavuconazole-cohort, respectively (P-value = 0.881). All-cause mortality at day + 180 was 2.4% (5/210) and 6.3% (6/95) in the voriconazole-cohort and isavuconazole-cohort, respectively (P-value = 0.089). When compared to voriconazole, isavuconazole was a safer and as effective primary AFP during the first 3 months after HCT.

LAY SUMMARY

When compared to voriconazole, isavuconazole is a safer and as effective primary antifungal prophylaxis during the first 3 months after allogeneic hematopoietic cell transplant, with lower rates of hepatotoxicity, and similar rates of fungal infections and all-cause mortality.

Clinical Considerations of Isavuconazole Administration in High-Risk Hematological Patients: A Single-Center 5-Year Experience

Background

There are limited real-life data on isavuconazole prophylaxis and treatment of invasive mold infections (IMI) in hematological patients and allogeneic hematopoietic cell transplant (HCT) recipients.

Objectives

Primary objective was to describe the indications of real-life isavuconazole administration at a university hospital. Secondary objectives included the description of liver function tests and QTc interval between baseline and end of treatment (EOT), clinical outcomes and breakthrough IMI by the EOT.

Patients/Methods

This was a 5-year single-center retrospective study of all adult patients with acute myeloid leukemia and/or allogeneic HCT recipients who received isavuconazole as prophylaxis and/or treatment between June 1, 2016, and July 31, 2020.

Results

Among 30 identified patients, the indications for isavuconazole administration were adverse events associated with prior antifungal treatment (N: 18, 60%: hepatotoxicity, renal insufficiency, long QTc interval, neurotoxicity, and potential drug–drug interactions in 6, 4, 3, 1 and 4 patients, respectively), clinical efficacy (N: 5, 16.6%), and other reasons (N: 10, 33.3%; 5/10 patients treated with isavuconazole to facilitate hospital discharge with orally administered appropriate treatment). Alanine aminotransferase significantly decreased from baseline (mean: 129 IU/L, range: 73, 202) to a mean of 48 IU/L (range: 20, 80) by day 14 (P-value: 0.02), 23.5 IU/L (range: 20, 27) by day 28 (P-value: 0.03) and 16.5 IU/L (range: 16, 17) by day 42 (P-value: 0.009). The QTc interval decreased from baseline (mean: 456.8 ms, range: 390, 533) to EOT (mean: 433.8 ms, range: 400, 472; P-value: 0.03). The mean isavuconazole plasma concentration was 2.9 mg/L (range: 0.9, 6.7). There was no breakthrough IMI observed.

Conclusion

Isavuconazole is a safe and reliable antifungal agent in complex hematological patients, with relatively low hepatotoxicity and QTc interval shortening properties.

Isavuconazole for the prophylaxis and treatment of invasive fungal disease: A single-center experience

BACKGROUND

Invasive fungal disease (IFD) is a serious complication among the immunocompromised population. Isavuconazole is a newer broad-spectrum antifungal agent with promising efficacy and safety. However, there remains limited data to favor its use over current first-line agents.

OBJECTIVES

We aimed to evaluate isavuconazole use and describe rates of associated breakthrough invasive fungal disease (bIFD).

METHODS

A single-center, retrospective study was conducted to evaluate patients receiving isavuconazole for prophylaxis or treatment of IFD between July 1, 2017 and December 31, 2018. Patient-related and outcomes data were extracted from electronic medical records. Descriptive statistics were used to analyze our findings.

RESULTS

A total of 54 patients received 61 isavuconazole courses. Isavuconazole was most commonly prescribed for primary prophylaxis in the acute myeloid leukemia (AML) and allogeneic hematopoietic stem cell transplant (HSCT) population along with treatment for possible invasive fungal disease. The primary reasons for choosing isavuconazole included QTc shortening effects, decreased risk of acute kidney injury, broader spectrum of activity, and concern for breakthrough invasive fungal disease on a different prophylactic agent. We found a breakthrough rate of 8.5% for patients and 7.8% for courses.

CONCLUSIONS

Isavuconazole appears to be a promising alternative for prophylaxis and treatment of invasive fungal disease. We observed similar bIFD rates and improved tolerability when compared to historical data for posaconazole and voriconazole.

Isavuconazole-Animal Data and Clinical Data

The treatment of invasive fungal infections has deeply evolved in the last years with the inclusion of new antifungals, mainly new azoles (i.e., posaconazole, isavuconazole), to the therapeutic armamentarium. This review focuses on the role of isavuconazole for treating the most important invasive fungal infections both in animals and humans (hematological and non-hematological patients).

Isavuconazole in Hematological Patients: Results of a Real-Life Multicentre Observational Seifem Study

Invasive fungal diseases (IFDs) remain a major clinical issue in patients with hematological malignancies (HMs). To confirm the efficacy and safety of the new azole isavuconazole (ISV) in a clinical care setting, we planned a multicenter retrospective study; we collected data on all possible/probable/proven IFDs in patients with HMs treated with ISV in 17 centers. Between July 2016 and November 2018, 128 patients were enrolled, and 122 were fully evaluable. ISV was employed as the 1st line therapy in 43 (35%) patients and as a subsequent therapy in 79 (65%) patients. The response rate was 82/122 patients (67.2%); it was similar when using ISV as a 1st or 2nd line treatment (60.5% vs 70.9%, respectively; p = 0.24). In multivariate analysis, both female sex (OR: 2.992; CI: 1.22-7.34) and induction phase of treatment (OR: 3.953; CI: 1.085-14.403) were predictive of a favorable response. At a median follow-up of 5 months, 43 (35.2%) patients were dead; the 1-year overall survival (OS) was 49.9%. In multivariate analysis, the response to ISV (OR: 0.103; CI: 0.041-0.262) and IFD refractoriness to previous antifungals (OR: 3.413; CI: 1.318-8.838) were statistically significant for OS. Adverse events (AEs) were reported in 15/122 patients (12.3%); grade 3-4 AEs were reported in 5 (4%) and led to ISV discontinuation. Our study confirms the safety and tolerability of ISV, also in diseases other than acute leukemia. Phase of hematological disease, gender and refractoriness to previous antifungals are the main predictive factors for the aforementioned response and outcome.