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

Shift from widespread to tailored antifungal prophylaxis in lymphoma patients treated with CD19 CAR T- cell therapy: results from a large retrospective cohort

BACKGROUND

Patients undergoing CD19 chimeric antigen receptor (CAR) T-cell therapy exhibit multiple immune deficits that may increase their susceptibility to infections. Invasive fungal infections (IFI) are life-threatening events in the setting of hematological diseases. However, there is ongoing debate regarding the optimal role and duration of antifungal prophylaxis in this specific patient population.

OBJECTIVES

The objective of this study was to provide a comprehensive overview of the evolution of IFI prophylactic strategies over time and to assess IFI incidence rates in a cohort of patients with relapsed or refractory (R/R) lymphoma treated with CAR-T cell therapy.

STUDY DESIGN

Single-center, retrospective study from a cohort of patients with R/R B-cell lymphoma treated with CD19 CAR-T cell therapy between April 2016 and March 2023. Group A (April 2016- August 2020) consisted of patients primarily treated with fluconazole, irrespective of their individual IFI risk profile. In Group B (September 2020- March 2023) antifungal prophylaxis was recommended only for high-risk patients.

RESULTS

Overall, 330 patients were included. Antifungal prophylaxis was prescribed to 119/142 (84%) patients in Group A and 58/188 (31%) in Group B (p<0.001). Anti-mold azoles were prescribed to 8 (5.6%) patients in Group A and 21 (11.2%) patients in Group B. In Group A, 42 (29%) patients switched to another antifungal, 9 (21%) because of toxicity, with 6 cases of transaminitis and 3 cases of prolonged QTc. In Group B, 21 (11.2%) patients switched the antifungal drug, mainly from fluconazole or micafungin to a mold-active agent following revised guidelines. No difference was found in liver toxicity between the two groups at infusion, day 10, and day 30. No significant differences were observed between the groups. IFI following CAR T-cell therapy were rare, with one case of cryptococcal meningoencephalitis in group A (0.7%) and one case of invasive aspergillosis in group B (0.5%), both occurring in patients on micafungin prophylaxis.

CONCLUSION

In this large single-center cohort of patients with R/R lymphoma treated with CAR T-cells, we show that individualized prophylaxis, alongside careful management of CAR T-cell related toxicities like CRS, was associated with a very low IFI rate, avoiding the risk of unnecessary toxicities, drug-drug interactions, and high costs.

Controversies in the clinical management of chronic pulmonary aspergillosis

Chronic pulmonary aspergillosis has a range of manifestations from indolent nodules to semi-invasive infection. Patients may be asymptomatic or have chronic symptoms such as cough and weight loss or present with life-threatening haemoptysis. The physician can choose from a range of available therapies including medical therapy with antifungals, minimally invasive therapy with intracavitary antifungal therapy and surgery involving open thoracotomy or video-assisted thoracoscopic surgery. The patients with the most severe forms of pulmonary infection may not be surgical candidates due to their underlying pulmonary condition. The management of haemoptysis can include tranexamic acid, bronchial artery embolisation, antifungals or surgery. There are few controlled studies to inform clinicians managing complex cases, so a multidisciplinary approach may be helpful.

Approaches for posaconazole therapeutic drug monitoring and their clinical benefits

OBJECTIVE

This review examines the progress of research on posaconazole therapeutic drug monitoring (TDM) that has focused on differences in the TDM of posaconazole after clinical application in different formulations and in different populations, the factors that affect posaconazole concentrations, the advantages of posaconazole TDM in terms of clinical efficacy and cost savings, and measurement methods.

METHODS

A literature search (2006 to 2024) was performed in PubMed and Embase with the following search terms: noxafil, posaconazole hydrate, posaconazole, drug monitoring, therapeutic drug monitoring, and TDM. Abstracts of review articles, prospective studies, and retrospective studies were reviewed.

RESULTS

TDM should be implemented earlier for posaconazole tablets and injections than for oral posaconazole suspensions. Posaconazole TDM is beneficial for improving clinical efficacy, and the incidence of breakthrough invasive fungal infections (IFIs) can be significantly reduced by gradually adjusting the posaconazole dose in response to TDM in patients with inadequate trough concentrations. Early TDM allows more patients to achieve target therapeutic posaconazole concentrations. TDM can also facilitate dose adjustments, which reduce the cost of this expensive drug. Different assay techniques, including chromatography, microbiological detection, chemofluorimetry, paper spray mass spectrometry, and capillary electrophoresis, can be used for posaconazole TDM.

CONCLUSIONS

Posaconazole TDM has potential clinical utility and cost-saving benefits and could improve the outcomes of IFI treatment.

In vivo pharmacodynamic characterization of a next-generation polyene, SF001, in the invasive pulmonary aspergillosis mouse model

SF001 is a next-generation polyene antifungal drug in development, designed to have increased specificity to fungal ergosterol, which is absent in humans, and decreased binding to cholesterol. SF001 demonstrates long-acting, potent, broad-spectrum fungicidal activity. The goal of the current study was to determine the pharmacodynamic index and target of SF001 in an immunocompromised mouse model of invasive pulmonary aspergillosis against six Aspergillus fumigatus isolates. Minimum inhibitory concentration (MIC) values ranged from 0.5 to 2.0 mg/L. Plasma and epithelial lining fluid (ELF) pharmacokinetics were performed following single intraperitoneal doses of 1, 4, 16, and 64 mg/kg. Treatment efficacy was assessed with each of the six fungal isolates using daily doses of SF001 ranging from 0.25 to 64 mg/kg/day over a 96-h treatment duration. Efficacy was assessed by A. fumigatus quantitative PCR of conidial equivalents from lung homogenates. Nonlinear regression analysis using the Hill equation demonstrated that the 24-h exposure-response relationships for both plasma and ELF area under the concentration/MIC and Cmax/MIC ratios were strong and relatively similar [coefficient of determination (R2) = 0.74-0.75). Exposure-response relationships included a median plasma 24-h Cmax/MIC target for stasis and 1-log kill endpoint of 0.5 and 0.6, respectively. The present studies demonstrated in vitro and in vivo SF001 potency against A. fumigatus. These results have potential relevance for SF001 clinical dose selection and evaluation of susceptibility breakpoints.

Management of Polypharmacy and Potential Drug-Drug Interactions in Patients with Pulmonary Aspergillosis: A 2-Year Study of a Multidisciplinary Outpatient Clinic

Pulmonary aspergillosis mainly affects elderly patients, patients with pulmonary complications, patients with hematological malignancies, organ transplant recipients, or critically ill patients. Co-morbidities may result in a high rate of polypharmacy and a high risk of potential drug-drug interaction (pDDI)-related antifungal azoles, which are perpetrators of several pharmacokinetic- and pharmacodynamic-driven pDDIs. Here, we report the results of the first 2-year study of an outpatient clinic focusing on the management of therapies in patients with pulmonary aspergillosis. All patients who underwent an outpatient visit from May 2021 to May 2023 were included in this retrospective analysis. A total of 34 patients who were given an azole as an antifungal treatment (53% voriconazole, 41% isavuconazole, and 6% itraconazole) were included. Overall, 172 pDDIs were identified and classified as red- (8%), orange- (74%), or yellow-flag (18%) combinations. We suggested handling polypharmacy in those patients using specific diagnostic and pharmacologic interventions. As expected, red-flag pDDIs involved mainly voriconazole as a perpetrator (71%). However, nearly 30% of red-flag pDDIs were not related to antifungal therapy. These findings highlight the importance of conducting an overall assessment of the pharmacologic burden and the key role played by a multidisciplinary team for the optimization of therapies in patients with pulmonary aspergillosis.

Targeting Aspergillus allergen oryzin with a chemical probe at atomic precision

We report the molecular basis of Aspergillus fumigatus oryzin, allergen Asp f 13, or alkaline proteinase ALP1, containing the sequence motif His-Asp-Ser of the subtilisin family, structure, and function at atomic detail. Given the resolution of the data (1.06 Å), we use fragment molecular replacement with ideal polyalanine α-helices to determine the first crystal structure of oryzin. We probe the catalytic serine through formation of an irreversible bond to a small molecule compound, specifically labeling it, describing the amino acid residues performing the catalytic function. Defined by a self-processed pro-peptide, the active site architecture shapes up pocket-like subsites that bind to and unveil the S1'-S4' substrate binding preferences. We use molecular modeling to dock a model of the pro-peptide in the S1-S4 region and to dock collagen along the active site cleft. Opposite to the face harboring the catalytic serine, the enzyme binds to a calcium ion in a binding site created by backbone flipping. We use thermal unfolding to show that this metal ion provides structural stability. With no known host inhibitor identified thus far, this structure may hasten the progress of developing new therapeutic agents for diseases caused by pathogenic fungi.

Identification of the shared gene signatures between pulmonary fibrosis and pulmonary hypertension using bioinformatics analysis

Pulmonary fibrosis (PF) and pulmonary hypertension (PH) have common pathophysiological features, such as the significant remodeling of pulmonary parenchyma and vascular wall. There is no effective specific drug in clinical treatment for these two diseases, resulting in a worse prognosis and higher mortality. This study aimed to screen the common key genes and immune characteristics of PF and PH by means of bioinformatics to find new common therapeutic targets. Expression profiles are downloaded from the Gene Expression Database. Weighted gene co-expression network analysis is used to identify the co-expression modules related to PF and PH. We used the ClueGO software to enrich and analyze the common genes in PF and PH and obtained the protein-protein interaction (PPI) network. Then, the differential genes were screened out in another cohort of PF and PH, and the shared genes were crossed. Finally, RT-PCR verification and immune infiltration analysis were performed on the intersection genes. In the result, the positive correlation module with the highest correlation between PF and PH was determined, and it was found that lymphocyte activation is a common feature of the pathophysiology of PF and PH. Eight common characteristic genes (ACTR2, COL5A2, COL6A3, CYSLTR1, IGF1, RSPO3, SCARNA17 and SEL1L) were gained. Immune infiltration showed that compared with the control group, resting CD4 memory T cells were upregulated in PF and PH. Combining the results of crossing characteristic genes in ImmPort database and RT-PCR, the important gene IGF1 was obtained. Knocking down IGF1 could significantly reduce the proliferation and apoptosis resistance in pulmonary microvascular endothelial cells, pulmonary smooth muscle cells, and fibroblasts induced by hypoxia, platelet-derived growth factor-BB (PDGF-BB), and transforming growth factor-β1 (TGF-β1), respectively. Our work identified the common biomarkers of PF and PH and provided a new candidate gene for the potential therapeutic targets of PF and PH in the future.

Pharmacokinetics in Penguins Compared to Other Avian Species: A Review of Enrofloxacin and Voriconazole

Australasia is home to unique and endangered avian species. Drug administration to this group of animal patients for prophylaxis and treatment is challenging from a number of different perspectives. A key limitation for optimal drug dosing in birds is the lack of published pharmacokinetic studies to guide dose requirements. The aim of this review was to systematically investigate published literature on pharmacokinetics in penguin species and compare that with the pharmacokinetics of other avian species with a focus on two drugs: enrofloxacin and voriconazole. The review was conducted following PRISMA guidelines. A systematic literature search was performed in Pubmed, Embase, Scopus, and Web of Science databases. A key finding is that penguin pharmacokinetics differs from other avian species, with weight-adjusted AUC and Cmax values higher than most other avian species (e.g., for enrofloxacin, the AUC in the African penguin is 85.7 μg h/mL, which is more than double the other bird species). Doses for some avian species may be successfully extrapolated from other avian species; however, it appears important to consider factors other than just body weight (e.g., clearance mechanism and drug physicochemical characteristics). Consequently, there is an important need for robust pharmacokinetic data in wildlife species to ensure optimal therapy for this special group of patients. As part of this review, we identify key aspects that should be considered when estimating dose in species for which there is limited pharmacokinetic information available.

Recent drug development and treatments for fungal infections

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

Lung and gut microbiomes in pulmonary aspergillosis: Exploring adjunctive therapies to combat the disease

Species within the Aspergillus spp. cause a wide range of infections in humans, including invasive pulmonary aspergillosis, chronic pulmonary aspergillosis, and allergic bronchopulmonary aspergillosis, and are associated with high mortality rates. The incidence of pulmonary aspergillosis (PA) is on the rise, and the emergence of triazole-resistant Aspergillus spp. isolates, especially Aspergillus fumigatus, limits the efficacy of mold-active triazoles. Therefore, host-directed and novel adjunctive therapies are required to more effectively combat PA. In this review, we focus on PA from a microbiome perspective. We provide a general overview of the effects of the lung and gut microbiomes on the growth of Aspergillus spp. and host immunity. We highlight the potential of the microbiome as a therapeutic target for PA.

Isavuconazole for COVID-19-Associated Invasive Mold Infections

Isavuconazole is a broad-spectrum antifungal drug recently approved as a first-line treatment for invasive aspergillosis and as a first or alternative treatment for mucormycosis. The purpose of this review was to report and discuss the use of isavuconazole for the treatment of COVID-19-associated aspergillosis (CAPA), and COVID-19-associated mucormycosis (CAM). Among all studies which reported treatment of CAPA, approximately 10% of patients were reportedly treated with isavuconazole. Considering 14 identified studies that reported the use of isavuconazole for CAPA, isavuconazole was used in 40% of patients (95 of 235 treated patients), being first-line monotherapy in over half of them. We identified six studies that reported isavuconazole use in CAM, either alone or in combination therapy. Overall, isavuconazole was used as therapy in 13% of treated CAM patients, frequently as combination or sequential therapy. The use of isavuconazole in CAPA and CAM is complicated by the challenge of achieving adequate exposure in COVID-19 patients who are frequently obese and hospitalized in the ICU with concomitant renal replacement therapy (RRT) or extracorporeal membrane oxygenation (ECMO). The presence of data on high efficacy in the treatment of aspergillosis, lower potential for drug-drug interactions (DDIs) and for subtherapeutic levels, and no risk of QT prolongation compared to other mold-active azoles, better safety profile than voriconazole, and the possibility of using an intravenous formulation in the case of renal failure are the advantages of using isavuconazole in this setting.

Invasive Pulmonary Aspergillosis in Hospital and Ventilator-Associated Pneumonias

Pneumonia is the commonest nosocomial infection complicating hospital stay, with both non-ventilated hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) occurring frequently amongst patients in intensive care. Aspergillus is an increasingly recognized pathogen amongst patients with HAP and VAP, and is associated with significantly increased mortality if left untreated.Invasive pulmonary aspergillosis (IPA) was originally identified in patients who had been profoundly immunosuppressed, however, this disease can also occur in patients with relative immunosuppression such as critically ill patients in intensive care unit (ICU). Patients in ICU commonly have several risk factors for IPA, with the inflamed pulmonary environment providing a niche for aspergillus growth.An understanding of the true prevalence of this condition amongst ICU patients, and its specific rate in patients with HAP or VAP is hampered by difficulties in diagnosis. Establishing a definitive diagnosis requires tissue biopsy, which is seldom practical in critically ill patients, so imperfect proxy measures are required. Clinical and radiological findings in ventilated patients are frequently non-specific. The best-established test is galactomannan antigen level in bronchoalveolar lavage fluid, although this must be interpreted in the clinical context as false positive results can occur. Acknowledging these limitations, the best estimates of the prevalence of IPA range from 0.3 to 5% amongst all ICU patients, 12% amongst patients with VAP and 7 to 28% amongst ventilated patients with influenza.Antifungal triazoles including voriconazole are the first-line therapy choice in most cases. Amphotericin has excellent antimold coverage, but a less advantageous side effect profile. Echinocandins are less effective against IPA, but may play a role in rescue therapy, or as an adjuvant to triazole therapy.A high index of suspicion for IPA should be maintained when investigating patients with HAP or VAP, especially when they have specific risk factors or are not responding to appropriate empiric antibacterial therapy.