Intervention: Warfarin
Trial phase: Phase 3
ATC code: B01AA03
SMILES: CC(=O)CC(c1ccccc1)c1c(O)c2ccccc2oc1=O
Sex: All
Age groups: Adult | Older Adult
Healthy volunteers: No
Participants at risk: 72
Group description: Oral warfarin titrated to an INR of 2-3

warfarin : Oral warfarin (1mg or 2.5mg) titrated to an INR of 2-3.
Eligibility criteria:
Inclusion Criteria:

Diagnosis of IPF
Age between 35 and 80, inclusive
Capable of understanding and signing consent

Progression despite conventional therapy (standard of care). Progression defined as:

Worsened dyspnea
FVC decreased by >=10% predicted OR
DLCO decreased by >=10% absolute OR
Reduction of oxygenation saturation >= 5% with or without exertion on a constant oxygen (02) administration
Worsened radiographic findings (chest x-ray or high-resolution computed tomography)

Exclusion Criteria:

Current enrollment in another investigational protocol
Current treatment with an investigational drug (i.e., participating in an active investigational drug protocol) within the previous 4 weeks or 5 times the half-life of the investigational agent, whichever is longer, prior to screening
Subject is actively listed for lung transplantation at the time of enrollment

Subjects who will not be able to perform/complete the study, in the judgment of the physician investigator or coordinator, for at least 3 months. For example:

Subject has current signs or symptoms of severe, progressive or uncontrolled comorbid illnesses such as: renal, hepatic, hematologic, gastrointestinal, endocrine, cardiac, neurologic, or cerebral disease, or any laboratory abnormality which would pose/suggest a risk to the subject during participation in the study.
Subject has a transplanted organ requiring immunosuppression
History of substance abuse (drugs or alcohol) within the 2 years prior to screening, history of noncompliance to medical regimens, inability or unwillingness to perform INR monitoring, or other condition/circumstance that could interfere with the subject's adherence to protocol requirements (e.g. psychiatric disease, lack of motivation, travel, etc).
Have any known active malignancy or have a history of malignancy within the previous 2 years (an example of an exception is a non-melanoma skin cancer that has been treated with no evidence of recurrence for at least 3 months) that might increase the risk of bleeding.
Estimated life expectancy < 12 months due to a non-pulmonary cause.
Subject has another respiratory disease that is predominant (as judged by the PI) in addition to IPF.

Anticoagulation-related exclusions include:

Current anticoagulation therapy with warfarin
Increased risk of bleeding (e.g. uncorrectable inherited or acquired bleeding disorder)
Platelet count < 100,000 or hematocrit < 30% or > 55%
History of severe gastrointestinal bleeding within 6 months of screening
History of cerebral vascular accident (CVA) within 6 months of screening
High risks of falls as judged by the PI
Surgery or major trauma within the past 30 days
Pregnancy, or lack of use of birth control method in women of childbearing age
Any condition that, in the determination of the PI, is likely to require anticoagulation therapy during the study.

Clopidogrel and aspirin combination therapy for > 30 days duration is exclusionary.

(Aspirin monotherapy [81-325 mg daily] or clopidogrel monotherapy are acceptable. Combination clopidogrel and aspirin <=81mg/day for ≤30 days is also acceptable. NSAIDS are discouraged; acetaminophen may be substituted.)

Patients on prasugrel are excluded. Prasugrel must be stopped for one week prior to starting study drug.