Immunology and Biologics in the Treatment of Allergic Bronchopulmonary Aspergillosis in Cystic Fibrosis

Allergic bronchopulmonary aspergillosis (ABPA) is mediated by hypersensitivity reactions to Aspergillus fumigatus, which is ubiquitous in the environment. People with Cystic Fibrosis (PwCF) are at an increased risk for developing ABPA, which can lead to frequent pulmonary exacerbations and progressive decline in lung function. In the age of highly effective modulator therapies (HEMT), PwCF have improved clinical outcomes and overall life expectancy, but they continue to suffer from comorbidities such as ABPA, which may be difficult to diagnose and treat. Establishing the diagnosis of ABPA in PwCF requires high clinical suspicion due to similarities in symptoms with the underlying disease. First-line treatment involves corticosteroids and anti-fungals, which have multiple side effects and drug interactions, especially with HEMT. Given this challenge, biologics have gained attention as potential agents directly targeting the Th-2 inflammatory pathway of ABPA with good tolerability and without significant drug interactions with HEMT. In this review, we discuss the diagnostic process and management of ABPA in PwCF, including a brief overview of the current literature on biologic agents.