Efficacy and safety of micafungin for prophylaxis of invasive fungal infections in patients undergoing haplo-identical hematopoietic SCT

New Targeted Drugs for Acute Myeloid Leukemia and Antifungals: Pharmacokinetic Challenges and Opportunities

BACKGROUND

Acute myeloid leukemia (AML) is a life-threatening disease whose treatment is made difficult by a number of mutations or receptor overexpression in the proliferating cellular clones. Life expectancy of patients diagnosed with new, relapsed-refractory, or secondary AML has been improved by drugs targeted at such moieties. Regrettably, however, clinical use of new AML drugs is complicated by pharmacokinetic interactions with other drugs the patient is exposed to.

SUMMARY

The most relevant drug-drug interactions (DDI) with clinical implications build on competition for or induction/inhibition of CYP3A4, which is a versatile metabolizer of a plethora of pharmacological agents. Here, we review DDI between AML drugs and the agents used to prevent or treat invasive fungal infections (IFI). The pathophysiology of AML, characterized by functionally defective white blood cells and neutropenic/immunosuppressive effects of concomitant induction chemotherapy, can in fact increase the risk of infectious complications, with IFI causing high rates of morbidity and mortality. Triazole antifungals, such as posaconazole, are strong inhibitors of CYP3A4 and may thus cause patient's overexposure to AML drugs that are metabolized by CYP3A4. We describe potential strategies to minimize the consequences of DDI between triazole antifungals and targeted therapies for AML and the role that collaboration between clinical pharmacologists, hematologists, and clinical or laboratory microbiologists may have in these settings.

KEY MESSAGES

Therapeutic drug monitoring and clinical pharmacology stewardship could represent two strategies that best express multidisciplinary collaboration for improving patient management.

Systemic antifungal strategies in allogeneic hematopoietic stem cell recipients hospitalized in french hematology units: a post-hoc analysis of the cross-sectional observational AFHEM study

Background

Invasive fungal diseases (IFD) remain a major complication of allogeneic hematopoietic stem cell transplantation (alloHSCT) and are associated with high mortality rates in patients receiving alloHSCT. Antifungal prophylaxis is increasingly being used in the management of IFDs in patients receiving alloHSCT.

Methods

A post-hoc analysis of the cross-sectional observational AFHEM study was carried out to describe the use of antifungal drugs in real-life clinical practice in alloHSCT recipients hospitalized in French hematological units.

Results

A total of 147 alloHSCT recipients were enrolled; most were adults (n = 135; 92%) and had received alloHSCT < 6 months prior to enrollment (n = 123; 84%). Overall, 119 (81%) patients received a systemic antifungal therapy; of these, 95 (80%) patients received antifungal prophylaxis. Rates of patients receiving systemic antifungal treatment were similar irrespective of transplant time, neutropenic, and graft-versus-host disease status. Among patients on systemic antifungal treatment, 83 (70%) received an azole, 22 (18%) received an echinocandin, and 16 (13%) received a polyene.

Conclusions

This work provides evidence of the antifungal strategies used in alloHSCT recipients hospitalized in French hematological units. Unlike earlier studies, the AFHEM study showed that prophylaxis appears to be the leading antifungal strategy used in alloHSCT recipients in France.

Consensus guidelines for optimising antifungal drug delivery and monitoring to avoid toxicity and improve outcomes in patients with haematological malignancy and haemopoietic stem cell transplant recipients, 2021

Antifungal agents can have complex dosing and the potential for drug interaction, both of which can lead to subtherapeutic antifungal drug concentrations and poorer clinical outcomes for patients with haematological malignancy and haemopoietic stem cell transplant recipients. Antifungal agents can also be associated with significant toxicities when drug concentrations are too high. Suboptimal dosing can be minimised by clinical assessment, laboratory monitoring, avoidance of interacting drugs, and dose modification. Therapeutic drug monitoring (TDM) plays an increasingly important role in antifungal therapy, particularly for antifungal agents that have an established exposure-response relationship with either a narrow therapeutic window, large dose-exposure variability, cytochrome P450 gene polymorphism affecting drug metabolism, the presence of antifungal drug interactions or unexpected toxicity, and/or concerns for non-compliance or inadequate absorption of oral antifungals. These guidelines provide recommendations on antifungal drug monitoring and TDM-guided dosing adjustment for selected antifungal agents, and include suggested resources for identifying and analysing antifungal drug interactions. Recommended competencies for optimal interpretation of antifungal TDM and dose recommendations are also provided.

Evaluation of a primary antifungal prophylaxis protocol for preventing invasive mold infections after allogeneic hematopoietic stem cell transplantation

INTRODUCTION

Invasive mold infections contribute to morbidity and mortality in patients undergoing allogeneic hematopoietic stem cell transplantation. The optimal strategy for primary antifungal prophylaxis in this patient population remains uncertain.

METHODS

Medical records of patients who underwent allogeneic hematopoietic stem cell transplantation between 1 January 2013 and 31 December 2017 were retrospectively reviewed. Adult patients were included if they received micafungin followed by fluconazole, with the option to escalate to voriconazole, for antifungal prophylaxis. The primary outcome was the incidence rate of proven or probable invasive mold infection. Secondary outcomes were time to invasive mold infection diagnosis, invasive mold infection-related mortality, and risk factors associated with invasive mold infection.

RESULTS

Two hundred patients were included in the study, a majority of whom underwent matched unrelated (46%) or matched related (33%) donor transplants. The incidence rate of proven or probable invasive mold infection was 18.4 cases per 100 patient-years, with a one-year cumulative incidence of 14%. Median time to proven or probable invasive mold infection was 94 days post-transplant (IQR 26-178), with invasive mold infection-related mortality occurring in 18 (64%) of 28 patients diagnosed with invasive mold infection. Comparison of invasive mold infection-free survival by potential risk factors failed to show any significant differences.

CONCLUSIONS

In this real-life cohort of allogeneic hematopoietic stem cell transplantation recipients, the incidence of proven or probable invasive mold infection was higher than expected based on previous literature. In the absence of standard guidance on anti-mold prophylaxis in this patient population and given that unique risk factors for invasive mold infection may differ between institutions, it is essential that centers performing allogeneic hematopoietic stem cell transplantation routinely monitor their antifungal prophylaxis strategies for effectiveness.

Efficacy of Rezafungin in Prophylactic Mouse Models of Invasive Candidiasis, Aspergillosis, and Pneumocystis Pneumonia

Antifungal prophylaxis is recommended to prevent invasive fungal disease caused by Candida spp., Aspergillus spp., and Pneumocystis jirovecii in patients at risk for opportunistic infections, such as allogeneic blood or marrow transplant recipients, patients with hematological disease undergoing chemotherapy, or patients on immunosuppressive therapies. Current approaches to antifungal prophylaxis require multiple agents to cover these key fungi. Rezafungin, a novel echinocandin designed for next-generation properties (e.g., greater stability and long-acting pharmacokinetics for once-weekly dosing), has demonstrated in vitro activity against Candida and Aspergillus spp. and efficacy against Pneumocystis spp. biofilms. Rezafungin was evaluated in in vivo studies of prophylactic efficacy using immunosuppressed mouse models of invasive candidiasis, aspergillosis, and Pneumocystis pneumonia. Rezafungin reduction of Candida CFU burden was generally greater with increasing drug concentrations (5, 10, or 20 mg/kg) and when rezafungin was administered closer to the time of fungal challenge (day -1, -3, or -5). Similarly, in the aspergillosis model, survival rates increased with drug concentrations and when rezafungin was administered closer to the time of fungal challenge. Against Pneumocystismurina, rezafungin significantly reduced trophic nuclei and asci counts at all doses tested. Rezafungin prevented infection at the two higher doses compared to vehicle and had comparable activity to the active control trimethoprim-sulfamethoxazole at human equivalent doses for prevention. These findings support phase 3 development of rezafungin and the potential for single-agent prophylaxis against invasive fungal disease caused by Candida spp., Aspergillus spp., and Pneumocystis jirovecii.

Use of micafungin as antifungal prophylaxis in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) in Spain (GETH-MIC)

Introduction

The fungal infections remain an important problem in the allogeneic stem cell trasnsplantation (allo-SCT) setting and thus, anti-fungal prophylaxis is commonly used. The antifungal drug should offer activity, at least against Candida and Aspergillus spp., a good safety profile and low probability interactions. Micafungin could theoretically fulfill these requisites. The aim of the study was to describe the experience with micafungin as primary prophylaxis in patients undergoing allo-SCT in a cohort of Spanish centres, and to evaluate its efficacy and tolerability in this population.

Material and methods

Retrospective multicentre observational study including all consecutive adult patients admitted for allo-SCT in participating centres of the Grupo Español de Trasplante Hematopoyético (GETH), from January 2010 to December 2013, who received micafungin as primary prophylaxis during the neutropenic period.

Results

A total of 240 patients from 13 centres were identified and 159 patients were included for the analysis. Most patients (95.6%) received 50 mg/day of micafungin. During the follow-up, 7 (4.4%) patients developed breakthrough invasive fungal disease, 1 proven and 6 probable; one patient discontinued the drug because of serious drug interactions. Prophylaxis with micafungin was considered effective in 151 (94.9%) patients.

Conclusions

According to our experience, micafungin is an appropriate alternative for antifungal prophylaxis in patients undergoing an allo-HSCT, because its efficacy, its low profile of drug interactions and side-effects.

Micafungin prophylaxis for acute leukemia patients undergoing induction chemotherapy

Background

Micafungin is a well-tolerated and effective prophylactic antifungal agent used in hematologic diseases. In this prospective trial, we evaluated the efficacy and safety of prophylactic micafungin during first induction chemotherapy in patients with acute leukemia. We also compared outcomes of prophylactic micafungin with those of prophylactic posaconazole in acute myeloid leukemia (AML).

Methods

Medically fit patients with newly diagnosed acute leukemia received 50 mg micafungin intravenously once daily from the initiation of first induction chemotherapy to recovery of neutrophil count, suspected fungal infection, or unacceptable drug-related toxicity (Clinicaltrials.gov number, NCT02440178). The primary end point was incidence of invasive fungal infection, and the secondary end points were adverse events of prophylactic micafungin and mortality during induction therapy.

Results

The 65 patients (median age = 51 years, male:female = 34:31) enrolled in this study had diagnoses of AML (33, 50.8%), acute lymphoblastic leukemia (31, 47.7%), and acute biphenotypic leukemia (1, 1.5%). Median duration of micafungin treatment was 24 days (range 1–68), with proven invasive fungal disease in one patient (1.5%) and possible fungal infection in two patients (3.1%). Three of the patients (4.6%) experienced the following adverse events, but all events were tolerable: liver function abnormality (Grade 2, n = 1; Grade 3, n = 1) and allergic reaction (Grade 2, n = 1). Three patients died during induction therapy, and invasive aspergillosis pneumonia was the cause of death for one of those patients. Overall, 19 patients (29.2%) discontinued prophylactic micafungin, and 18 (27.7%) patients switched to another antifungal agent. We observed no fungal infections caused by amphotericin B-resistant organisms. In AML patients, outcomes of prophylactic micafungin during induction chemotherapy did not differ significantly with those of prophylactic posaconazole with regard to incidence of fungal infections, rate of discontinuation, or safety.

Conclusions

Our study demonstrates that prophylactic micafungin is safe and effective in patients with acute leukemia undergoing induction chemotherapy. Outcomes in patients with AML were similar to those of prophylactic posaconazole, indicating the usefulness of micafungin as a prophylactic antifungal agent during induction chemotherapy for AML.

Trial registration

Clinicaltrials.gov NCT02440178, registered May 12th 2015.

Micafungin versus posaconazole prophylaxis in acute leukemia or myelodysplastic syndrome: A randomized study

OBJECTIVES

To compare the effectiveness and tolerability of micafungin versus posaconazole during chemotherapy-induced neutropenia in acute leukemia (AL) and myelodysplastic syndrome (MDS).

METHODS

Patients with AL or MDS undergoing chemotherapy were randomized to open-label micafungin 100 mg intravenously daily or posaconazole suspension 400 mg orally twice daily until neutrophil recovery, up to 28 days. Patients were followed for 12 weeks. The primary endpoint was prophylaxis failure (premature discontinuation due to infection, intolerance, adverse event, or death). Time to failure and survival were calculated by Kaplan-Meier analysis.

RESULTS

From March 2011 to May 2016, 113 patients who received at least 2 doses of prophylaxis were analyzed (58 patients randomized to micafungin and 55 to posaconazole). Prophylaxis failure occurred in 34.5% and 52.7% of patients on micafungin and posaconazole, respectively (P = 0.0118). The median number of days on prophylaxis was 16 [interquartile range (IQR) 12-20] for micafungin and 13 [IQR 6-16] for posaconazole (P = 0.01). Micafungin failures were largely due to antifungal treatment; posaconazole failures were mostly due to gastrointestinal intolerance or adverse effects. IFI incidence and survival were similar between study arms.

CONCLUSIONS

Our data support micafungin as alternative antifungal prophylaxis in patients with AL and MDS.

Sequential systematic anti-mold prophylaxis with micafungin and voriconazole results in very low incidence of invasive mold infections in patients undergoing allogeneic hematopoietic stem cell transplantation

Recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT) are at high risk for invasive mold infections (IMI). The goal of the study is to describe the incidence and outcome of IMI in patients after allo-HSCT in a large cohort of patients receiving anti-mold prophylaxis. We conducted a retrospective review of 988 consecutive adults who underwent allo-HSCT in our center from 2008 through 2014. Standard prophylaxis consisted of micafungin 150 mg IV daily from admission to day +7 ± 3 followed by voriconazole until day +75 to +100. Cases meeting criteria for proven or probable IMI according to EORTC-MSG criteria were included. Median age at HSCT was 54 years. The most common diagnoses were acute myeloid leukemia (n = 351, 36%) and lymphoid malignancies (n = 248, 25%). Matched related or unrelated donors (URD) were used in 686 (69%) patients, mismatched URD in 142 (14%) and cord blood units in 154 (16%). Twenty-one patients were diagnosed with IMI after allo-HSCT, 19 probable and 2 proven, and one patient was diagnosed postmortem. Microbiological diagnosis was established in 9 cases, 5 of them being Aspergillus. One-year cumulative incidence (CI) of IMI was 1.6% (95% CI 0.9-2.5) while 12-week overall survival after IMI was 39% (95% CI 24-65) Analyzed by disease, there was a trend for a higher 1-year CI of IMI in patients with ALL (5% [95% CI 1.6-11.4]) when compared with AML (1.4%), MDS (1.5%) and lymphoma (1.2%), P = .06. The 1-year CI of IMI after transplantation is low in patients receiving anti-mold prophylaxis with micafungin bridged to voriconazole, although these infections are associated with a higher risk of mortality.

Antifungal Therapy in Hematopoietic Stem Cell Transplant Recipients

Invasive fungal infections (IFI) represent a major hindrance to the success of hematopoietic stem cell transplantation (HSCT), contributing substantially to morbidity and infection-related mortality. During the most recent years several reports indicate an overall increase of IFI among hematologic patients, in particular, invasive aspergillosis, that may be explained, at least partially, by the fact that diagnoses only suspected in the past, are now more easily established due to the application of serum biomarkers and early use of CT scan. Along with new diagnostic options, comes the recent development of novel antifungal agents that expanded the spectrum of activity over traditional treatments contributing to the successful management of fungal diseases. When introduced in 1959, Amphotericin B deoxycholate (d-AmB) was a life-saving drug, and the clinical experience over 50 years has proven that this compound is effective although toxic. Given the superior safety profile, lipid formulations of AmB have now replaced d-AmB in many circumstances. Similarly, echinocandins have been investigated as initial therapy for IA in several clinical trials including HSCT recipients, although the results were moderately disappointing leading to a lower grade of recommendation in the majority of published guidelines. Azoles represent the backbone of therapy for treating immunocompromised patients with IFI, including voriconazole and the newcomer isavuconazole; in addition, large studies support the use of mold-active azoles, namely voriconazole and posaconazole, as antifungal prophylaxis in HSCT recipients.

The aim of the present review is to summarize the clinical application of antifungal agents most commonly employed in the treatment of IFI.

Epidemiology and risk factors for invasive fungal diseases in hematopoietic stem cell transplantation

PURPOSE OF REVIEW

Knowledge of the epidemiology and the risk factors of invasive fungal diseases (IFDs) in hematopoietic stem cell transplant (HSCT) recipients is a critical determinant of the prevention, diagnosis and therapeutic antifungal strategy. Transplant procedures are characterized by a continuous evolution; therefore, an update of the epidemiological findings of IFDs in HSCT populations is needed.

RECENT FINDINGS

In the last few years, the incidence and the clinical risk factors of IFD, mainly in allogeneic HSCT populations, have been investigated in prospective, multicenter studies. New findings in the different types and phases of transplant may be considered for a redefinition of the level of risk of IFD after HSCT. Furthermore, recent studies have uncovered associations between host's and/or donor's genetic variants and immunological risk for IFDs, in particular invasive aspergillosis.

SUMMARY

Evolution of the transplant procedures was followed by an important change in the epidemiology and clinical risk of IFD after allogeneic HSCT. A new stratification of subpopulations according to different clinical infectious risk and genetic susceptibility may be considered to predict those patients most vulnerable to IFD and update tailored antifungal strategies.

Comparison of Three Distinct Prophylactic Agents Against Invasive Fungal Infections in Patients Undergoing Haplo-identical Hematopoietic Stem Cell Transplantation and Post-transplant Cyclophosphamide

Over the past decade, invasive fungal infections (IFIs) have remained an important problem in patients undergoing allogeneic haematopoietic stem cell transplantation (Allo-HSCT). The optimal approach for prophylactic antifungal therapy has yet to bedetermined.

We conducted a retrospective analysis, comparing the safety and efficacy of micafungin 50mg/day vs. fluconazole 400mg/day vs. itraconazole 200mg/day as prophylaxis for adult patients with various haematological diseases receiving haploidentical hematopoietic stem cell transplantation (haplo-HSCT) followed by high-dose cyclophosphamide (PT-Cy).

Overall, 99 patients were identified: 30 patients received micafungin, 50 and 19 patients received itraconazole and fluconazole, respectively. After a median follow-up of 12 months (range: 1–51), proven or probable IFIs were reported in 3 patients (10%) in the micafungin, 5 patients in the itraconazole (10%) and 2 patients (11%) in the fluconazole group (p=0.998). Fewer patients in the micafungin group had invasive aspergillosis (1 [3%] vs. 3 [6%] in the itraconazole vs. 2 [11%] in the fluconazole group, p=0.589). Four patients (13%) in the micafungin group vs 13 (26%) patients in the itraconazole group and 10 (53%) patients in the fluconazole received empirical antifungal therapy (P = 0.19).

No serious adverse events related to treatment were reported by patients, and there was no treatment discontinuation because of drug-related adverse events in both groups.

The present analysis shows that micafungin did better than fluconazole in preventing invasive aspergillosis after transplant in these high-risk hematological diseases, as expected. In addition, micafungin was more effective than itraconazole in preventing all IFI episodes when also considering possible fungal infections. Future prospective studies would shed light on this issue, concerning this increasingly used transplant platform.

Different doses of micafungin for prophylaxis of invasive fungal diseases in hemato-oncological high-risk patients: a web-based non-interventional trial in four large university hospitals in Germany

INTRODUCTION

Treatment indications of new antifungals in clinical practice often deviate from the strict criteria used in controlled clinical trials. Under routine clinical conditions, beneficial and adverse effects, not previously described in clinical trials may be observed. The aim of this study was to describe customary prescription and treatment strategies of micafungin (MCFG).

METHODS

A registry was set up on www.ClinicalSurveys.net and physicians were invited to provide retrospective information on cases they had treated with MCFG. Documentation comprised demographic information, underlying disease, effectiveness, safety, and tolerability of MCFG.

RESULTS

A total of 125 episodes of patients hospitalized between September 2009 and February 2012 were documented, of which 7 had to be excluded because of incomplete documentation. The most common risk factors of patients were hematological malignancy (n = 116, 98.3%) and antibiotic treatment >3 days (n = 115, 97.5%). MCFG was administered as prophylaxis in 106 (89.9%) patients. Median duration of MCFG application as prophylaxis was 21 days (range: 3-78); 53 of the patients (50%) received a dose of 50 mg, while the other 53 (50%) received 100 mg/day. For the different doses, prophylactic outcome was rated as success in 42 (79.2%) vs. 52 (98.1%; P = 0.004) patients. Fifty-five patients (51.9%) were treated with posaconazole before initiation of MCFG. Four patients (7.5%) developed a proven invasive fungal disease (IFD) while being treated with 50 mg MCFG, compared to no patient treated with 100 mg (P = 0.118). At the end of MCFG prophylaxis, 24 (22.6%) patients were switched to fluconazole and 64 (60.3%) patients to posaconazole.

CONCLUSION

Our study shows clinical effectiveness of MCFG prophylaxis with low rates of breakthrough fungal infections. In most cases, MCFG was part of a multi-modal antifungal prophylactic strategy. Investigators reported fewer proven IFDs in patients receiving therapeutic doses of MCFG as prophylaxis.