Inclusion Criteria:

          -  Histologically confirmed non-squamous NSCLC,

          -  Metastatic NSCLC of stage IV (according to American Joint Committee on Cancers) or
             recurrent NSCLC)

          -  Patients without activating epidermal growth factor receptor (EGFR) mutation

          -  Patients without anaplastic lymphoma kinase (ALK) rearrangement

          -  Patients must have measurable lesion by RECIST 1.1

          -  Refractory disease defined by documented progression during the first-line
             chemotherapy based on a platinum doublet and third-generation drug (four or less
             cycles) according to RECIST V.1.1

          -  Age ≥18 years and < 75 years

          -  Performance status (PS) 0-1

          -  Life expectancy of more than 12 weeks.

          -  No history of other malignancy within the last 5 years, except for adequately treated
             carcinoma in situ of the cervix or basal cell or spinocellular carcinoma of the skin.

          -  Adequate organ function, evidenced by the following laboratory results within 3 weeks
             prior to randomization: Normal hepatic function: bilirubin < 1.5 x N, ALT (alanine
             transaminase) and AST (aspartate aminotransferase ) < 2.5 x N or <5 x N in case of
             liver metastasis

          -  Normal renal function (calculated creatinine clearance ≥ 45 mL/min).

          -  Normal Calcemia

          -  Normal haematological function (polynuclear neutrophils > 1.5 G/l, platelets > 100
             G/l).

          -  Anticoagulation with a vitamin K antagonist and low-molecular-weight heparin (LMWH) is
             authorized.

          -  Antiplatelet treatment (aspirin authorized if < 325 mg/d)

          -  Treatment with dipyridamole, ticlopidine, clopidogrel is not authorized

          -  Women of child bearing potential must use double effective contraception.

          -  Men might be surgically sterile or accept to use an effective contraceptive procedure
             during and until 6 months after the treatment.

          -  Written informed consent to participate in the study.

        Exclusion Criteria:

          -  Known hypersensitivity to the trial drugs (nintedanib (vargatef®), docetaxel), peanut,
             soya, to their excipients

          -  Controlled disease after first line treatment

          -  Contra indication to the use of the backbone treatment

          -  Patients who were withdrawn from first line treatment due to toxicity without
             documented disease progression or who received placebo (in the context of a clinical
             trial) as prior treatment are not eligible.

          -  Previous treatment with docetaxel

          -  Small-cell lung cancer, bronchioloalveolar cancer, neuroendocrine cancer.

          -  Previous therapy with vascular endothelial growth factor (VEGF) inhibitors except
             bevacizumab

          -  Centrally located tumour with radiographic evidence of local invasion of local blood
             vessels

          -  Radiographic evidence of cavitary or necrotic tumours at screening

          -  Chemo-, hormone-, radio-(except for brain and extremities) or immunotherapy or therapy
             with monoclonal antibodies or small tyrosine kinase inhibitors within the past 4 weeks
             prior to treatment with the trial drug.

          -  Toxicity non resolute due to prior treatment > grade I (except alopecia).

          -  Radiotherapy (except extremities) within the past 3 months prior to baseline imaging

          -  Persistence of clinically relevant therapy related toxicity from previous radiotherapy

          -  Active brain metastases (e.g. stable for <4 weeks, no adequate previous treatment with
             radiotherapy, symptomatic, requiring treatment with anti-convulsants; dexamethasone
             therapy will be allowed if administered as stable dose for at least one month before
             inclusion).

          -  Uncontrolled arterial hypertension.

          -  Concurrent radiotherapy, except for palliative bone irradiation.

          -  Other concurrent severe illnesses (congestive heart failure, unstable angina,
             significant arrhythmia or myocardial infarction less than 12 months before study
             entry).

          -  Stroke less than 6 months before study entry.

          -  Psychiatric or neurological disorders preventing the patient from understanding the
             nature of the trial

          -  Grade >=1 peripheral neuropathy

          -  Uncontrolled infection.

          -  Caval syndrome

          -  Other organic disorders preventing inclusion in the trial

          -  Malabsorption syndrome

          -  Pregnancy and breast-feeding

          -  Surgery less than two months before study entry.

          -  Follow-up not feasible.

          -  Incarcerated and institutionalized