Study of ARO-MMP7 Inhalation Solution in Healthy Participants and Participants With Idiopathic Pulmonary Fibrosis

Inclusion Criteria (NHVs): * Normal pulmonary function tests at Screening * Normal electrocardiogram (ECG) at Screening * Non-smoking * Female participants cannot be pregnant or lactating * Male and female participants of childbearing potential must agree to use highly effective contraception and must not donate eggs/sperm during the study and for at least 90 days following end of study or last dose of study drug, whichever is later. Inclusion Criteria (IPF Participants): * Age ≥ 45 years at Screening * Clinical diagnosis consistent with IPF based upon established criteria confirmed by review of high-resolution computed tomography (HRCT) and surgical lung biopsy findings (if available) * Safely able to undergo bronchoscopy * Stable IPF disease at Screening with minimum life expectancy of ≥ 12 months from Screening * Female participants cannot be pregnant or lactating * Male and female participants of childbearing potential must agree to use highly effective contraception and must not donate eggs/sperm during the study and for at least 90 days following end of study or last dose of study drug, whichever is later. Exclusion Criteria (NHVs): * Acute lower respiratory infection within 30 days prior to first dose or acute upper respiratory infection within 7 days prior to first dose * Positive coronavirus disease (COVID-19) test during Screening window * Any history of chronic pulmonary disease or anaphylaxis * Human immunodeficiency virus (HIV) infection, seropositive for hepatitis B virus (HBV), seropositive for hepatitis C virus (HCV) * Uncontrolled hypertension * History of significant cardiac disease * History of major surgery within 12 weeks prior to first dose * Unwilling to limit alcohol consumption to within moderate limits for the duration of the study * Use of illicit drugs * Use of an investigational agent or device within 30 days prior to first dose Exclusion Criteria (IPF Participants): * Interstitial lung disease (ILD) associated with known primary cause * Positive COVID-19 test during Screening window * IPF exacerbation within 6 weeks prior to first dose * Lower respiratory tract infection requiring antibiotics or antivirals within 30 days prior to first dose * Smoking cigarettes or e-cigarettes within 3 months prior to first dose * Use of systemic corticosteroid therapy within 30 days prior to first dose * Initiation or cessation of antifibrotic therapy or change of antifibrotic dose regimen within 10 weeks prior to first dose * Any history of lung transplant or plan to undergo transplant during the course of the study * Any concomitant pulmonary disease that could interfere with the evaluation of the study drug or interpretation of patient safety or study results * HIV infection, seropositive for HBV, seropositive for HCV * Uncontrolled hypertension * History of significant cardiac disease * History of major surgery within 12 weeks prior to first dose * Unwilling to limit alcohol consumption to within moderate limits for the duration of the study * Use of illicit drugs * Use of an investigational agent or device within 30 days prior to first dose Note: additional inclusion/exclusion criteria may apply per protocol