GOAL: GA101 Plus Pixantrone for Relapsed Aggressive Lymphoma

Inclusion Criteria: * Patients aged ≥ 18 years * Histologically proven diagnosis of diffuse large cell B-cell lymphoma (DLBCL), follicular lymphoma (FL) IIIB or transformed indolent lymphoma according to the World Health Organization classification (central pathology review) * Relapsed disease * Eastern Cooperative Oncology Group (ECOG) performance Status ≤2, unless tumor associated * Adequate cardiac reserve: Serum Troponin level must be consistent with no significant acute or chronic myocardial damage and there should be no evidence of symptomatic disease * No curative option available * At least 1 measurable tumor mass (\>1.5 cm x \>1.0 cm) or bone marrow infiltration * Adequate bone marrow (BM) reserve: Platelets of at least 100.000/µl (in case of extensive BM-infiltration 75.000/µl may be acceptable after discussion with the coordinating investigator), absolute neutrophil count of at least 1000/µl. Adequate hepatic and renal function: Alanine aminotransferase \<2.5 x upper limit of normal (ULN); Aspartate aminotransferase \<2.5 x ULN, total bilirubin \<1.5 x ULN * No active Hepatitis B or C or HIV-infection * Measured or calculated creatinine clearance \>30 mL/min * Fresh tumor biopsy or archived tissue available * Ability of patients to understand nature, importance and individual consequences of clinical trial. * Signed informed consent * Women post-menopausal for more than two years can participate in the trial. Women with childbearing potential can only participate, if they are surgically sterile or a negative pregnancy test (serum or urine) is available before trial and they are willing to practice a highly effective and medically accepted contraception method during trial and for a period of 18 months post-treatment. Reliable contraception comprises systematic contraceptives (oral, implant, injection) or diaphragm / condoms / intrauterine devices (IUP) with spermicide. * Male patients are advised to use contraceptive methods (preferably barrier) during treatment and for a period of 6 months post-treatment Exclusion Criteria: * Lymphoma other than DLBCL, FL IIIB, transformed indolent Non-Hodgkin's lymphoma (NHL) * Central nervous System (CNS) involvement (brain MRI (Magnetic resonance Imaging) is required only in cases of clinically suspicious involvement) * Pregnant or breast-feeding women * Severe concomitant disease (e.g. uncontrolled arterial hypertension, heart failure (NYHA III-IV), uncontrolled diabetes mellitus, pulmonary fibrosis, uncontrolled hyperlipoproteinaemia) * Myocardial infarction within the last 6 months * Active uncontrolled infections including HIV-positivity, active Hepatitis B or C * Vaccination with live vaccine within last 4 weeks * Mental status precluding patient's compliance * Known CD20 negativity * Diagnosed or treated for a malignancy other than NHL except: adequately treated non-melanoma skin cancer, curatively treated in-situ cancer of the cervix, Ductal Carcinoma in Situ (DCIS) of the breast, or other solid tumors curatively treated with no evidence of disease for \>3 years, or prostate cancer with a life expectancy of more than 2 years * Treatment with any approved anticancer agent within last 2 weeks. Any agents must have been stopped at least 2 weeks prior to day 1 of GOAL treatment and all treatment related adverse events must have returned to Grade 1. * Prior exposition to Obinutuzumab or Pixantrone * History of hypersensitivity to medicinal products with similar chemical structure as the trial medication * Active participation in other interventional clinical trials during the present clinical trial or within the last 2 weeks prior to treatment initiation. Concurrent participation in non-treatment studies is not excluded * Medical or psychological conditions that would jeopardize an adequate and orderly completion of the trial.