Reasons unrelated to safety issues

This prescreening study is being conducted to diagnose ABPA in selected patients with asthma and to increase the potential number of eligible participants for the ongoing Study 601-0018 of PUR1900 in subjects with ABPA. See: NCT05667662.

Additionally, this prescreening study may provide information that could assist the conduct of future studies conducted by Pulmatrix.

See NCT05667662 for a detailed description fo the main ABPA study. This prescreening study is designed to diagnose ABPA in patients with asthma to potentially increase the number of eligible participants for the ongoing NCT05667662 study. This diagnosis will be confirmed through chest x-rays and a blood sample.

Inclusion Criteria:

1. Provide written informed consent before the performance of any study-specific procedures at the in-clinic visit.

2. Is a male or female ≥18 years old.

3. Has a BMI of ≥18.0 and <40.0 kg/m2 at the in-clinic visit.

4. Meets the following criteria:

   1. Has a diagnosis of asthma.
   2. At least 1 exacerbation requiring a systemic glucocorticosteroid(s) or hospital admission in the last 10 months.
   3. For patients on a biologic agent, at least one exacerbation requiring a systemic glucocorticosteroid(s) or hospital admission must have occurred at least 3 months after the initiation of the biologic agent.

5. Is willing and able to comply with all study procedures

Exclusion Criteria:

1. Has used omalizumab (Xolair®) in the 11 months prior to screening or plans to use omalizumab during the study.

2. 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, CF, or Churg-Strauss syndrome.

3. Currently requiring medications that are sensitive substrates for CYP3A4-mediated metabolism or medications that are contraindicated during and 2 weeks after treatment with oral formulations of itraconazole without the possibility of washout (See Appendix 4).

4. Smoking marijuana or tobacco, the use of e-cigarettes, vaping, or any other smoking is prohibited during the study.

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Patients will be enrolled at study sites in North America, Europe, and the Asia-Pacific region participating in Study 601-0018. Only patients who meet all eligibility criteria will be enrolled in the prescreening study and have blood samples drawn for laboratory testing at the in-clinic visit.