• A clinical diagnosis of PH-ILD.

• Subject voluntarily gives informed consent.

• Subjects aged between 18 and 85 years at the time of signing informed consent.

• Subjects must agree to practice protocol-defined birth control during the study period.

‣ Males with a partner of childbearing potential must practice protocol-defined birth control for the duration of treatment and at least 96 hours after discontinuing the IP.

⁃ Female subjects of childbearing of potential (including those \<1-year post menopausal) must practice protocol-defined birth control during the conduct of the study and for 30 days after the last dose of IP (males only during exposure to IP).

⁃ Women not of childbearing potential are defined as:

• Post-menopausal women (at least 12 months with no menses without an alternative medical cause); in women \<45 years of age, a high follicle-stimulating hormone (FSH) level in the post-menopausal range may be used to confirm a post-menopausal state in women not using hormonal contraception or hormonal replacement therapy; OR

∙ Have had a hysterectomy and/or bilateral oophorectomy, bilateral salpingectomy, or bilateral tubal ligation/occlusion, at least 6 weeks prior to screening; OR

∙ Have a congenital or acquired condition that prevents childbearing.

• The subject has a confirmed diagnosis of any form of interstitial lung disease based on high resolution computed tomography (HRCT) of the chest within 180 days prior to screening or at screening or a historical surgical biopsy (or other appropriate tissue sampling (e.g., cryobiopsy). The subject can have other findings (e.g., emphysema) if this is not the predominant feature on the scan.

• Subjects have undergone RHC during the screening period with the following documented parameters:

‣ Pulmonary vascular resistance (PVR) ≥4 Wood units and

⁃ Pulmonary capillary wedge pressure (PCWP) of ≤12 mmHg \[if PVR ≥4 Wood units to \<6.25 Wood units\] or PCWP ≤15 mmHg \[if PVR ≥6.25 Wood units\] (a left ventricular end diastolic pressure \[LVEDP\] will be acceptable if a reliable PCWP cannot be obtained) and

⁃ A mean pulmonary arterial pressure (PAP) of \>20 mmHg.

• Subjects must have a baseline 6-minute walk distance ≥100 meters and ≤500 meters.

• Subjects agree to a repeat RHC, Chest CT, and MRI prior to study completion.

• Subjects on chronic treatment for underlying lung disease (i.e., nintedanib or pirfenidone or immunosuppressive agents etc.) must be on a stable/optimized dose for ≥30 days prior to screening and have been receiving treatment for ≥90 days.

⁃ Subjects on supportive medications (e.g., inhalers for asthma) must be on stable doses for ≥30 days prior to screening.

⁃ In the Investigator's opinion, the subject must be able to consent for themselves and communicate with local staff using interpreters if necessary. Subjects must agree to attend all study visits and be contactable through a cellular device or landline.

⁃ Subjects must have clinical laboratory values within normal ranges or \<1.5 times the upper limit of normal (ULN) as specified by the testing laboratory.

⁃ Pulmonary function test (PFT) showing a percent predicted forced vital capacity (FVC) \<70% of predicted and diffusion capacity of carbon monoxide (DLCO) \<70% corrected for hemoglobin (Hb) value ≥25% and ≤90% at screening (DLCO determined locally must be \<70%) using the American Thoracic Society (ATS) standards.

⁃ Subjects with a prior diagnosis of connective tissue diseases, specifically systemic sclerosis (scleroderma), systemic lupus erythematosus, Sjogren's disease, polymyositis/dermatomyositis/antisynthetase syndrome, rheumatoid arthritis can be included in the study, but no more than 20% of total subjects.

⁃ Negative serology test for hepatitis B surface antigen and hepatitis C antibody at Screening Visit.