Primary objective of this study is to investigate the long-term tolerability and safety profile of BIBF 1120 on top of pirfenidone treatment in patients with Idiopathic Pulmonary Fibrosis who have completed a prior clinical trial of BIBF 1120 (1199.31).

Secondary objectives are to assess effects on some efficacy criteria during long term treatment with BIBF 1120 on top of pirfenidone.

Inclusion criteria:

1. Written informed consent consistent with Good Clinical Practice (GCP) signed prior to entry into the study
2. Completion of 1199.31 study and still under treatment with pirfenidone at a stable dose

Exclusion criteria:

1. Any disease that may interfere with testing procedures or in judgement of investigator may interfere with trial participation or may put the patient at risk when participating in this trial. Reconsider carefully all exclusion criteria of trial 1199.31. However, patients may qualify for participation even though they meet the exclusion criteria (for 1199.31), if the investigators benefit-risk assessment remains favorable.

2. Any other investigational therapy received within 8 weeks before visit 1.

3. For female: Pregnant women or women who are breast feeding or of child bearing potential not using a highly effective method of birth control for both at least 4 weeks prior to enrolment and 10 weeks after last study drug intake.

   For male: Sexually active males not committing to using condoms both during the course of the study and ten weeks after last study drug intake (except if their partner is not of childbearing potential).

4. Known or suspected active alcohol or drug abuse.

5. Patients who require full-dose therapeutic anticoagulation (e.g. vitamin K antagonists, heparin), except low dose heparin and/or heparin flash as needed for maintenance of an indwelling intravenous device. As an example, prophylactic use of heparin, e.g. enoxaparin 2000 International unit (I.U.) subcutaneously (s.c.) per day, should be allowed.

6. Patients who require full-dose antiplatelet (e.g. acetyl salicylic acid, clopidogrel) therapy. As an example, chronic low-dose acetyl salicylic acid, below or equal to 100 mg per day, should be allowed.

7. Patient not compliant in previous trial, with trial medication or trial visits.

Treated set (TS): This analysis set included all patients who were given study medication and were documented to have taken at least one dose of the trial medication.

First drug administration until end of treatment, up to 5 years

Annual ROD in FVC results to be interpreted with caution & along with descriptive statistics as inferences used might not be valid as suggested by skewed distribution of data thus Absolute Change from baseline in FVC over time has been defined.