Nebulised liposomal-amphotericin-B as maintenance therapy in ABPA: a randomised, multicentre, trial

Amphotericin B in the Era of New Antifungals: Where Will It Stand?

Amphotericin B (AmB) has long stood as a cornerstone in the treatment of invasive fungal infections (IFIs), especially among immunocompromised patients. However, the landscape of antifungal therapy is evolving. New antifungal agents, boasting novel mechanisms of action and better safety profiles, are entering the scene, presenting alternatives to AmB's traditional dominance. This shift, prompted by an increase in the incidence of IFIs, the growing demographic of immunocompromised individuals, and changing patterns of fungal resistance, underscores the continuous need for effective treatments. Despite these challenges, AmB's broad efficacy and low resistance rates maintain its essential status in antifungal therapy. Innovations in AmB formulations, such as lipid complexes and liposomal delivery systems, have significantly mitigated its notorious nephrotoxicity and infusion-related reactions, thereby enhancing its clinical utility. Moreover, AmB's efficacy in treating severe and rare fungal infections and its pivotal role as prophylaxis in high-risk settings highlight its value and ongoing relevance. This review examines AmB's standing amidst the ever-changing antifungal landscape, focusing on its enduring significance in current clinical practice and exploring its potential future therapeutic adaptations.

Revised ISHAM-ABPA working group clinical practice guidelines for diagnosing, classifying and treating allergic bronchopulmonary aspergillosis/mycoses

BACKGROUND

The International Society for Human and Animal Mycology (ISHAM) working group proposed recommendations for managing allergic bronchopulmonary aspergillosis (ABPA) a decade ago. There is a need to update these recommendations due to advances in diagnostics and therapeutics.

METHODS

An international expert group was convened to develop guidelines for managing ABPA (caused by Aspergillus spp.) and allergic bronchopulmonary mycosis (ABPM; caused by fungi other than Aspergillus spp.) in adults and children using a modified Delphi method (two online rounds and one in-person meeting). We defined consensus as ≥70% agreement or disagreement. The terms "recommend" and "suggest" are used when the consensus was ≥70% and <70%, respectively.

RESULTS

We recommend screening for A. fumigatus sensitisation using fungus-specific IgE in all newly diagnosed asthmatic adults at tertiary care but only difficult-to-treat asthmatic children. We recommend diagnosing ABPA in those with predisposing conditions or compatible clinico-radiological presentation, with a mandatory demonstration of fungal sensitisation and serum total IgE ≥500 IU·mL-1 and two of the following: fungal-specific IgG, peripheral blood eosinophilia or suggestive imaging. ABPM is considered in those with an ABPA-like presentation but normal A. fumigatus-IgE. Additionally, diagnosing ABPM requires repeated growth of the causative fungus from sputum. We do not routinely recommend treating asymptomatic ABPA patients. We recommend oral prednisolone or itraconazole monotherapy for treating acute ABPA (newly diagnosed or exacerbation), with prednisolone and itraconazole combination only for treating recurrent ABPA exacerbations. We have devised an objective multidimensional criterion to assess treatment response.

CONCLUSION

We have framed consensus guidelines for diagnosing, classifying and treating ABPA/M for patient care and research.

CT Imaging Assessment of Response to Treatment in Allergic Bronchopulmonary Aspergillosis in Adults With Bronchial Asthma

BACKGROUND

One of the major challenges in managing allergic bronchopulmonary aspergillosis remains consistent and reproducible assessment of response to treatment.

RESEARCH QUESTION

What are the most relevant changes in CT scan parameters over time for assessing response to treatment?

STUDY DESIGN AND METHODS

In this ancillary study of a randomized clinical trial (NebuLamB), patients with asthma with available CT scan and without exacerbation during a 4-month allergic bronchopulmonary aspergillosis exacerbation treatment period (corticosteroids and itraconazole) were included. Changed CT scan parameters were assessed by systematic analyses of CT scan findings at initiation and end of treatment. CT scans were assessed by two radiologists anonymized to the clinical data. Radiologic parameters were determined by selecting those showing significant changes over time. Improvement of at least one, without worsening of the others, defined the radiologic response. Agreement between radiologic changes and clinical and immunologic responses was likewise investigated.

RESULTS

Among the 139 originally randomized patients, 132 were included. We identified five CT scan parameters showing significant changes at end of treatment: mucoid impaction extent, mucoid impaction density, centrilobular micronodules, consolidation/ground-glass opacities, and bronchial wall thickening (P < .05). These changes were only weakly associated with one another, except for mucoid impaction extent and density. No agreement was observed between clinical, immunologic, and radiologic responses, assessed as an overall response, or considering each of the parameters (Cohen κ, -0.01 to 0.24).

INTERPRETATION

Changes in extent and density of mucoid impaction, centrilobular micronodules, consolidation/ground-glass opacities, and thickening of the bronchial walls were found to be the most relevant CT scan parameters to assess radiologic response to treatment. A clinical, immunologic, and radiologic multidimensional approach should be adopted to assess outcomes, probably with a composite definition of response to treatment.

TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT02273661; URL: www.

CLINICALTRIALS

gov).

Clinical Manifestation and Treatment of Allergic Bronchopulmonary Aspergillosis

Allergic bronchopulmonary aspergillosis (ABPA) is a complex hypersensitivity reaction to airway colonization by Aspergillus fumigatus in patients with asthma and cystic fibrosis. The pathophysiology of ABPA involves a complex interplay between the fungus and the host immune response, which causes persistent inflammation and tissue damage. Patients present with chronic cough, wheezing, and dyspnea due to uncontrolled asthma. Characteristic symptoms include the expectoration of brownish mucus plugs. Radiographic findings often reveal fleeting pulmonary infiltrates, bronchiectasis, and mucus impaction. However, the definitive diagnosis of ABPA requires a combination of clinical, radiological, and immunological findings. The management of ABPA aims to reduce symptoms, prevent disease progression, and minimize the future risk of exacerbations. The treatment approach involves systemic glucocorticoids or antifungal agents to suppress the inflammatory response or fungal growth and prevent exacerbations. Biological agents may be used in patients with severe disease or glucocorticoid dependence. This review provides an overview of the clinical manifestations and current treatment options for ABPA.

Lipid-based nanomedicines for the treatment of bacterial respiratory infections: current state and new perspectives

The global threat posed by antimicrobial resistance demands urgent action and the development of effective drugs. Lower respiratory tract infections remain the deadliest communicable disease worldwide, often challenging to treat due to the presence of bacteria that form recalcitrant biofilms. There is consensus that novel anti-infectives with reduced resistance compared with conventional antibiotics are needed, leading to extensive research on innovative antibacterial agents. This review explores the recent progress in lipid-based nanomedicines developed to counteract bacterial respiratory infections, especially those involving biofilm growth; focuses on improved drug bioavailability and targeting and highlights novel strategies to enhance treatment efficacy while emphasizing the importance of continued research in this dynamic field.

Poorly controlled asthma - Easy wins and future prospects for addressing fungal allergy

Poorly controlled asthma is especially common in low resource countries. Aside from lack of access to, or poor technique with, inhaled beta-2 agonists and corticosteroids, the most problematic forms of asthma are frequently associated with both fungal allergy and exposure, especially in adults leading to more asthma exacerbations and worse asthma. The umbrella term 'fungal asthma' describes many disorders linked to fungal exposure and/or allergy to fungi. One fungal asthma endotype, ABPA, is usually marked by a very high IgE and its differential diagnosis is reviewed. Both ABPA and fungal bronchitis in bronchiectasis are marked by thick excess airway mucus production. Dermatophyte skin infection can worsen asthma and eradication of the skin infection improves asthma. Exposure to fungi in the workplace, home and schools, often in damp or water-damaged buildings worsens asthma, and remediation improves symptom control and reduces exacerbations. Antifungal therapy is beneficial for fungal asthma as demonstrated in nine of 13 randomised controlled studies, reducing symptoms, corticosteroid need and exacerbations while improving lung function. Other useful therapies include azithromycin and some biologics approved for the treatment of severe asthma. If all individuals with poorly controlled and severe asthma could be 'relieved' of their fungal allergy and infection through antifungal therapy without systemic corticosteroids, the health benefits would be enormous and relatively inexpensive, improving the long term health of over 20 million adults and many children. Antifungal therapy carries some toxicity, drug interactions and triazole resistance risks, and data are incomplete. Here we summarise what is known and what remains uncertain about this complex topic.

Relationship between Aspergillus and asthma

Fungal sensitization is highly prevalent in severe asthma. The relationship between fungus and asthma, especially Aspergillus fumigatus, has been the subject of extensive research. The ubiquitous presence of A. fumigatus, its thermotolerant nature, the respirable size of its conidia, and its ability to produce potent allergens are pivotal in worsening asthma control. Due to the diverse clinical manifestations of fungal asthma and the lack of specific biomarkers, its diagnosis remains intricate. Diagnosing fungal asthma requires carefully assessing the patient's clinical history, immunological tests, and imaging. Depending on the severity, patients with fungal asthma require personalized treatment plans, including inhaled corticosteroids and bronchodilators, and antifungal therapy. This review provides a comprehensive overview of the association between Aspergillus and asthma by reviewing the relevant literature and highlighting key findings. We discuss the diagnosis of various entities included in fungal asthma. We also debate whether newer definitions, including allergic fungal airway disease, offer any additional advantages over the existing ones. Finally, we provide the current treatment options for the individual entities, including A. fumigatus-associated asthma, severe asthma with fungal sensitization, and allergic bronchopulmonary mycoses.

Allergic bronchopulmonary aspergillosis: A multidisciplinary review

Allergic bronchopulmonary aspergillosis (ABPA) is a rare disease characterized by a complex allergic inflammatory reaction of airways against Aspergillus affecting patients with chronic respiratory diseases (asthma, cystic fibrosis). Exacerbation is often the way to diagnose ABPA and marks its evolution by its recurrent character leading to cortico-requirement or long-term antifungal treatment. Early diagnosis allows treatment of ABPA at an initial stage, preventing recurrence of exacerbations and long-term complications, mainly represented by bronchiectasis. This review of the literature aims to present the current state of the art in terms of diagnosis and treatment of ABPA from a multidisciplinary perspective. As there is no clinical, biological nor radiological specific sign, diagnostic criteria are regularly revised. They are mainly based on the elevation of total and specific IgE against Aspergillus fumigatus and the presence of suggestive CT abnormalities such as mucoid impaction and consolidations. ABPA management includes eviction of mold and pharmacological therapy. Exacerbations are treated in first line with a moderate dose of oral corticosteroids. Azole antifungal agents represent an alternative for the treatment of exacerbations and are the preferential strategy to reduce the future risk of exacerbations and for corticosteroids sparing. Asthma biologics may be of interest; however, their place remains to be determined. Avoiding complications of ABPA while limiting the side effects of systemic drugs remains a major challenge of ABPA management. Several drugs, including new antifungals and asthma biologics, are currently being tested and may be useful in the future.

Nebulized amphotericin B for preventing exacerbations in allergic bronchopulmonary aspergillosis: A systematic review and meta-analysis

BACKGROUND

Allergic bronchopulmonary aspergillosis (ABPA) is complicated by exacerbations in more than one-third of the subjects. Whether nebulized amphotericin B (NAB) therapy prevents ABPA exacerbations remains unclear.

OBJECTIVES

The primary objective of this systematic review and meta-analysis was to determine the frequency of subjects remaining exacerbation-free, one year after initiating NAB. The key secondary objectives were the time to first exacerbation and the safety of NAB therapy.

METHODS

We searched the PubMed and Embase databases for studies evaluating ≥5 subjects of ABPA managed with NAB. We report the pooled proportion of ABPA subjects remaining exacerbation free after one year. For the randomized controlled trials (RCTs), we estimate the pooled risk difference (RD) of exacerbation-free status at one year with NAB versus the control arm.

RESULTS

We included five studies for our analysis; three were observational (n = 28) and two RCTs (n = 160). The pooled proportion (95% confidence interval [CI]) of subjects remaining exacerbation free with NAB at one year was 76% (62-88). The pooled RD (95% CI) of an exacerbation-free status at one year was 0.33 (-0.12 to 0.78) and was not significantly different between the NAB and control arms. The time to first exacerbation was longer with NAB than with the standard therapy. No serious adverse events were reported with NAB.

CONCLUSION

NAB does not improve exacerbation-free status at one year; however, weak evidence suggests it delays ABPA exacerbations. More research using different dosing regimens is required.

Treatment of pulmonary mucormycosis with adjunctive nebulized amphotericin B (MUCONAB trial): Results of an open-label randomized controlled trial

BACKGROUND

The role of nebulized amphotericin B (NAB) in managing pulmonary mucormycosis (PM) is unknown.

METHODS

In this open-label trial, we randomized PM subjects to receive either intravenous liposomal amphotericin B (control arm, 3-5 mg/kg/day) alone or along with nebulized amphotericin B deoxycholate (NAB, 10 mg twice a day, every alternate day). The primary outcomes were: (1) overall response ('success' [complete or partial response] or 'failure' [stable disease, progressive disease, or death]) at 6 weeks; and (2) the proportion of subjects with adverse events (AE). The key secondary outcome was 90-day mortality. We performed a modified intention-to-treat (mITT) analysis where we included only subjects receiving at least a single dose of NAB.

RESULTS

Fifteen and 17 subjects were randomized to the control and NAB arms; two died before the first dose of NAB. Finally, we included 30 subjects (15 in each arm; mean age 49.8 years; 80% men) for the mITT analysis. Diabetes mellitus (n = 27; 16/27 were COVID-19-associated PM) was the most common predisposing factor. The overall treatment success was not significantly different between the control and the NAB arms (71.4% vs. 53.3%; p = .45). Twenty-nine subjects experienced any AE, but none discontinued treatment. The 90-day mortality was not significantly different between the control (28.6%) and NAB arm (53.3%; p = .26).

CONCLUSION

Adjunctive NAB was safe but did not improve overall response at 6 weeks. A different dosing schedule or nebulized liposomal amphotericin B may still need evaluation. More research is needed to explore other treatment options for PM.

Severe Fungal Asthma: A Role for Biologics and Inhaled Antifungals

Allergic asthma has traditionally been treated with inhaled and systemic glucocorticosteroids. A continuum of allergic fungal airways disease associated with Aspergillus fumigatus colonization and/or atopic immune responses that encompasses fungal asthma, severe asthma with fungal sensitization and allergic bronchopulmonary aspergillosis is now recognized along a phenotypic severity spectrum of T2-high immune deviation lung disease. Oral triazoles have shown clinical, anti-inflammatory and microbiologic efficacy in this setting; in the future inhaled antifungals may improve the therapeutic index. Humanized monoclonal antibody biologic agents targeting T2-high disease also show efficacy and promise of improved control in difficult cases. Developments in these areas are highlighted in this overview.

Comparative diagnostic accuracy of immunoprecipitation versus immunoassay methods for detecting A.fumigatus-specific IgG in allergic bronchopulmonary aspergillosis: a systematic review and meta-analysis

BACKGROUND

The diagnostic accuracy of immunoassays versus immunoprecipitation methods for detecting A.fumigatus-specific IgG in patients with allergic bronchopulmonary aspergillosis (ABPA) complicating asthma remains unclear.

METHODS

We performed a systematic review to identify studies describing both the methods in the same ABPA subjects. We assessed study quality using the QUADAS-2 tool. We derived the relative sensitivity and specificity using the HSROC meta-regression model. We calculated the number-needed-to-test using an immunoassay to detect one additional positive test in ABPA.

RESULTS

Our search yielded 20 studies (796 ABPA, 929 controls). The studies had a high risk of bias. The summary estimates for sensitivity and specificity of immunoprecipitation methods were 68.6% (95% CI, 48.4-83.5) and 93.8% (95% CI, 83.6-97.8), while for immunoassays they were 85.2% (95% CI, 73.3-92.3) and 84.6% (95% CI, 76.0-90.5), respectively. The relative sensitivity and specificity of immunoassays compared to immunoprecipitation tests were 1.29 (95% CI, 1.1-1.6) and 0.91 (95% CI, 0.85-0.97), respectively. The automated immunoassays (1.77; 95% CI, 1.1-2.8) had better relative sensitivity than the manual (1.1; 95% CI, 1.02-1.18) assays compared to immunoprecipitation. The relative specificity of manual immunoassays (0.95; 95% CI, 0.91-0.99) was significantly lower, while that of automated (0.88; 95% CI, 0.77-1.0) assays was lower but not statistically different. One additional positive result was detected for every 6 (95% CI, 5-7) tests performed with immunoassay (versus immunoprecipitation).

CONCLUSION

Manual immunoassays have higher sensitivity and lower specificity, while automated immunoassays have higher sensitivity and similar specificity than immunoprecipitation methods for detecting A.fumigatus-IgG in patients with ABPA.

Conventional Antifungals for Invasive Infections Delivered by Unconventional Methods; Aerosols, Irrigants, Directed Injections and Impregnated Cement

The administration of approved antifungals via unapproved formulations or administration routes (such as aerosol, direct injection, irrigation, topical formulation and antifungal-impregnated orthopedic beads or cement) may be resorted to in an attempt to optimize drug exposure while minimizing toxicities and/or drug interactions associated with conventional (systemic) administrations. Existing data regarding such administrations are mostly restricted to uncontrolled case reports of patients with diseases refractory to conventional therapies. Attribution of efficacy and tolerability is most often problematic. This review updates prior published summaries, reflecting the most recent data and its application by available prevention and treatment guidelines for invasive fungal infections. Of the various dosage forms and antifungals, perhaps none is more widely reported than the application of amphotericin B-containing aerosols for the prevention of invasive mold infections (notably Aspergillus spp.).