Study to Evaluate Itraconazole Administered as Inhaled Dry Powder in Adults With Asthma and Allergic Bronchopulmonary Aspergillosis

The goal of this clinical trial is to learn about PUR1900 as an inhaled, antifungal therapeutic for the treatment of allergic bronchopulmonary aspergillosis (ABPA) in patients with asthma. The main questions it aims to answer are:Is PUR1900 safe and well tolerated in adults with asthma and ABPA?Is there an effect of daily administration of PUR1900 on potential outcome measures in adults with asthma and ABPA?Is there fungal resistance to A. fumigatus?This study includes a 28-day screening period, a 112-day (16-week) treatment period, and a 56-day (8 week) observation period.Participants will take either 40mg of PUR1900, 20 mg of PUR1900 or Placebo for 112 days and complete an eDairy, answer questions about their asthma and complete peak respiratory flow measurements at home. They will come to the clinic approximate once a month during the treatment period and complete study assessments. At the end of the observation period participants will complete one more clinic visit. Participants who complete this study will be given the opportunity to continue on study drug in an open label extension study.

Inclusion Criteria:Is a male or female, ≥18 and ≤80 years old at the time of signing the informed consent.BMI of ≥18.0 and <40.0 kg/m2 at screening.Has a diagnosis of asthma, as per the Global Initiative for Asthma (GINA) 2018 updateHas a confirmed diagnosis of ABPA, as per the Modified International Society for Human and Animal Mycology (ISHAM) working group 2013 criteria, including a history of serum IgE ≥1000 IU/mL and a positive immediate skin test or increased IgE antibody to A. fumigatus and at least 2 of the 3 following supportive criteria: eosinophils >500 cells/µL, presence of precipitating antibody (or increased immunoglobulin G [IgG]) to A. fumigatus, consistent radiographic opacities at the time of diagnosis.Is currently considered to be in one of the following stages of ABPA: Stage 2 (Response), Stage 4 (Remission), Stage 5a (Treatment-dependent ABPA), or Stage 5b (Glucocorticoid-dependent asthma).At least 1 exacerbation requiring an oral steroid(s) in the last 12 months.Has a serum IgE ≥500 IU/mL at screening.Has a documented stable asthma medication regimen during the screening period.Can perform a valid, reproducible spirometry test with demonstration of a prebronchodilator FEV1 ≥50% of predicted normal for age, sex, race, and height.Can demonstrate the correct inhalation technique for the use of the delivery device.Subjects who are sexually active, male subjects able to father a child, and female subjects of childbearing potential must agree to follow contraception requirements.Exclusion Criteria:Currently requiring medications that are metabolized via the CYP3A4 isoenzyme system.Has evidence of ventricular dysfunction, such as congestive cardiac failure (New York Heart Association functional class III or IV), or a history of congestive cardiac failure. N-terminal pro B-type natriuretic peptide (NT pro BNP) will be checked at screening only. A subject with a confirmed value of >400 pg/mL will not be eligible to participate.Has used any systemic azole antifungal agent in the 6 weeks before first dose of study drug.Has a history of life-threatening asthma within the last 24 months, defined as an asthma episode that required intubation and/or was associated with hypercapnia, respiratory arrest, and/or hypoxic seizures.Has a current diagnosis of any chronic airway disease other than asthma, ABPA, or bronchiectasis believed to be related to ABPA, such as chronic obstructive pulmonary disease, pulmonary fibrosis, cystic fibrosis, or Churg-Strauss syndrome. A subject whose predominating clinical disease burden is related to bronchiectasis (e.g., a subject with 2 or more infective exacerbations of bronchiectasis in the past 12 months or a subject with chronic colonization with Pseudomonas aeruginosa) will be excluded. Refer to Appendix 4 for definition of bronchiectasis exacerbations.Had an occurrence of clinically significant bacterial, viral, or fungal infection that required systemic (oral or intravenous) antibiotics, antivirals, or antifungals within the 28 days before screening. Topical treatments, other than antifungals, are allowed.Had an occurrence of asthma or ABPA exacerbations within the 28 days before screening.Has the presence of hoarseness or oropharyngeal candidiasis at screening.Had a major trauma or surgery within the last 28-days before screening.Has a history of any clinically significant cardiovascular, renal, hepatic, or gastrointestinal disease or neurological or psychiatric disorder endocrine, immunological, or autoimmune disease or other medical condition that would affect the subject's safety or confound the assessment of study endpoints as judged by the Investigator.Has a history of any clinically significant drug or alcohol abuse in the past 6 months before screening, as judged by the Investigator.Has current tobacco or inhaled marijuana use or history of smoking or vaping including tobacco or marijuana within the last 6 months before screening.Has a history of allergic or hypersensitivity reaction or serious adverse reaction after dosing of itraconazole or other antifungal azoles.Has a history of serious adverse reaction or known serious hypersensitivity to any of the formulation excipients.Has a positive urine test result for drugs of abuse or cotinine at screening (unless, in the opinion of the Investigator, this can be explained by the subject's current medications).At screening, has alanine aminotransferase (ALT) or aspartate aminotransferase (AST) >2x upper limit of normal (ULN), white blood cell (WBC) count > 20,000 X 109/L, absolute neutrophil count <1000 cells/L, platelet counts <100,000 to >500,000 X 109/L, or hemoglobin <10 g/dLHas used omalizumab (Xolair®) in the 12 months prior to the first dose of study drug.Is a female of childbearing potential who is pregnant or lactating or who plans to become pregnant during the study. All female subjects must have a negative pregnancy test at screening and pre dose on Day 1. A woman is of childbearing potential unless she is either permanently sterile (hysterectomy, bilateral salpingectomy, bilateral oophorectomy, bilateral tubal occlusion/ligation, endometrial ablation) or postmenopausal (had no menses for 12 months without an alternative medical cause).Has a 12-lead ECG demonstrating a mean QT interval corrected by the Fridericia formula (QTcF) >450 msec for a male subject or >470 msec for a female subject at screening. A repeat triplicate ECG is allowed if a mean QTcF >450 msec for males and >470 msec for females is recorded at Visit 1.Has a history of allergic or hypersensitivity reaction or serious adverse reaction after dosing of itraconazole or other antifungal azoles.Has a planned or elective surgery, hospitalizations, or participation in other interventional studies any time during the study that may interfere with study logistics or safety.Has donated or had a loss of greater than 400 mL of blood within the 3 months before screening.Has other social, psychiatric, surgical, or medical conditions or screening laboratory abnormalities that may increase the risk associated with study participation or may interfere with the interpretation of study results and, in the judgement of the Investigator, would make the subject inappropriate for entry into the study.Received any investigational medical product in a clinical research study within the previous 3 months before first dose of study drug.Is a study site employee, an immediate family member of a study site employee, or a Sponsor employee.Has previously received PUR1900.