Phase II Study About Combination CHOP-21, Obinutuzumab and Ibrutinib in Untreated Young High Risk DLBCL Patients.

Inclusion Criteria: * Histologically confirmed Diffuse Large B-Cell Lymphoma (DLBCL) not otherwise specified (NOS) * Previously untreated disease * Age 18-60 * Age adjusted IPI=2-3 * Ann Arbor stage II-IV disease * Measurable disease ≥ 1.5 cm in longest diameter, and measurable in 2 perpendicular dimensions * Normal blood count as defined as: absolute neutrophil count ≥1.0 × 109/L independent of growth factor support, platelet count ≥ 100,000/mm3 or ≥50,000/mm3 if bone marrow (BM) involvement independent of transfusion support in either situation * Normal organ functions defined as: creatinine ≤2 times the upper limit of normal (ULN) or estimated Glomerular Filtration Rate (Cockroft- Gault) ≥40 ml/min/1.73m2, aspartate aminotransferase (AST) or alanine aminotransferase (ALT) ≤3× the ULN; total bilirubin ≤ 1.5 × the ULN unless bilirubin rise is due to Gilbert's syndrome or of nonhepatic origin: patients with documented Gilbert disease may be enrolled if total bilirubin is ≤ 3.0 × the ULN; International normalized ratio (INR) \< 1.5 × the ULN in the absence of therapeutic anticoagulation; partial thromboplastin time (PTT) or activated partial thromboplastin time (aPTT) \< 1.5 × the ULN in the absence of a lupus anticoagulant" * Patients with occult or prior hepatitis B infection (defined as HBsAg negative, anti-HBs positive and /or anti-HBc positive) may be included if hepatitis B virus (HBV) DNA is undetectable. These patients must be willing to undergo bi-monthly DNA testing and they should receive prophylaxis with Lamivudine * No active hepatitis C virus (HCV) infection * Known availability of biopsy material * No Central Nervous System (CNS) disease (meningeal and/or brain involvement by lymphoma) * Absence of active infections * Non peripheral neuropathy or active neurological non neoplastic disease of CNS * Non major surgical intervention prior 3 months to enrolment if not due to lymphoma and/or not other disease life-threatening that can compromise chemotherapy treatment * Patient with a history of curatively treated basal or squamous cell carcinoma or melanoma of the skin or in situ carcinoma of the cervix at any time prior to the study. * Patients with any other malignancy that has been treated with surgery alone with curative intent and the malignancy has been in remission without treatment for at least 5 years prior to enrolment. * Women of childbearing potential and men who are sexually active must be practicing a highly effective method of birth control during and after the study consistent with local regulations regarding the use of birth control methods for subjects participating in clinical trials. Men must agree to not donate sperm during and after the study. For females, these restrictions apply for 6 months after the last dose of study drug. For males, these restrictions apply for 6 months after the last dose of study drug. * Women of childbearing potential must have a negative serum (betahuman chorionic gonadotropin \[β-hCG\]) or urine pregnancy test at Screening. Women who are pregnant or breastfeeding are ineligible for this study. * Life expectancy \> 6 months * Sign (or their legally-acceptable representatives must sign) an informed consent document indicating that they understand the purpose of and procedures required for the study and are willing to participate in the study. Exclusion Criteria: * Any Other histologies than Diffuse Large B- Cell Lymphoma (DLBCL): composite or transformed disease and patients with follicular lymphoma IIIB * Primary mediastinal lymphoma (PMBL) * Known central nervous system lymphoma * Any prior lymphoma therapy * Contraindication to any drug in the chemotherapy regimen * Left ventricular ejection fraction (LVEF) \< 50% * Neuropathy ≥ grade 2 * Seropositive for or active viral infection with HBV * HBsAg positive * HBsAg negative, anti-HBs positive and /or anti-HBc positive with detectable viral DNA * Known seropositive active HCV * Human immunodeficiency virus (HIV) infection * Any of the following abnormal laboratory values (unless any of these abnormalities are due to underlying lymphoma): creatinine ≥ 2 times the ULN (unless creatinine clearance normal, or calculated creatinine clearance \< 40 mL/min (using the Cockcroft-Gault formula); AST or ALT ≥3 × the ULN; total bilirubin \>1.5 × the ULN: patients with documented Gilbert disease may be enrolled if total bilirubin is ≤ 3.0 × the ULN; INR \> 1.5 × the ULN in the absence of therapeutic anticoagulation; PTT or aPTT \> 1.5 × the ULN in the absence of a lupus anticoagulant" * History of stroke or intracranial hemorrhage within the past 6 months. * Requires anticoagulation with warfarin or equivalent vitamin K antagonists * Requires treatment with strong CYP3A inhibitors * History of clinically relevant liver or renal insufficiency; significant cardiac, vascular, pulmonary, gastrointestinal, endocrine, neurologic, rheumatologic, hematologic, psychiatric, or metabolic disturbances * Clinically significant cardiovascular disease such as uncontrolled or symptomatic arrhythmias, congestive heart failure, or myocardial infarction within 6 months of Screening, or any Class 3 (moderate) or Class 4 (severe) cardiac disease as defined by the New York Heart Association Functional Classification. * Vaccinated with live, attenuated vaccines within 4 weeks of enrollment * Presence of major neurological disorders * any uncontrolled active systemic infection requiring intravenous (IV) antibiotics * Major surgical intervention prior 4 weeks to enrollment if not due to lymphoma and/or other disease life-threatening that can compromise chemotherapy treatment * Prior malignancies other than lymphoma in the last 5 years with exception of currently treated basal or squamous cell carcinoma or melanoma of the skin or in situ carcinoma of the cervix * Any other coexisting medical or psychological condition that would preclude participation in the study or compromise ability to give informed consent. * Any life-threatening illness, medical condition, or organ system dysfunction which, in the investigator's opinion, could compromise the subject's safety, interfere with the absorption or metabolism of ibrutinib capsules, or put the study outcomes at undue risk. * If female, the patient is pregnant or breast-feeding