The purpose of this study is to evaluate the safety, tolerability, pharmacokinetics (PK) and pharmacodynamics (PD) of ARO-MMP7 in normal healthy volunteers (NHVs) and in participants with idiopathic pulmonary fibrosis (IPF). The study will initiate with NHVs receiving single ascending doses of ARO-MMP7. Following evaluation of safety and pharmacodynamic (PD) data, participants will receive multiple doses of ARO-MMP7.

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 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