Inclusion Criteria:

* Male or female patients aged ≥40 years based on the date of the written informed consent form
* Diagnosis of IPF as defined by American Thoracic Society/European Respiratory Society/Japanese Respiratory Society/Latin American Thoracic Association guidelines
* In a stable condition and suitable for study participation based on the results of medical history, physical examination, vital signs, 12-lead ECG, and laboratory evaluation
* Patients receiving local standard-of-care for IPF, defined as either pirfenidone or nintedanib, at a stable dose for at least 3 months prior to screening, or neither pirfenidone nor nintedanib. If the patients were on pirfenidone or nintedanib previously and have been off for at least 3 months prior to screening, they will be considered as not on any treatment for IPF
* Meeting all of the following criteria during the screening period:

* FVC ≥40% predicted of normal
* DLCO corrected for Hgb ≥25% and ≤80% predicted of normal.
* forced expiratory volume in the first second/FVC (FEV1/FVC) ratio ≥0.7 based on pre-bronchodilator value

Exclusion Criteria:

* Acute IPF exacerbation within 6 months prior to screening and/or during the screening period
* Patients who are unwilling to refrain from smoking within 3 months prior to screening and until the end of the study
* Female patients who are pregnant or nursing
* Abnormal ECG findings
* Use of any investigational drugs for IPF within 4 weeks prior to screening