Clinical Study With Blinatumomab in Patients With Relapsed/Refractory Diffuse Large B-cell Lymphoma (DLBCL)

The purpose of this study is to confirm whether the bispecific T-cell engager blinatumomab is effective and safe in the treatment of patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL).

DLBCL is an aggressive malignant disease which evolves from B-cells and affects mainly the lymphatic tissue. Due to its aggressive nature the disease is characterized by a fast course which is lethal without therapy. Potentially curative therapy options are available even at advanced stages. Standard-first line leads to a high initial response rate (85-90%) and an approximate cure rate of 50% of patients. Patients refractory to or with early relapse after this treatment (10-15%) have a very poor prognosis.

Blinatumomab is a bispecific single-chain antibody derivative against CD19 and CD3, designed to link B-cells and T-cells resulting in T-cell activation and a cytotoxic T-cell response against CD19 expressing cells.

This study consisted of a screening period, treatment period, and a follow-up efficacy and survival period. The core study comprises the treatment period to the 30 days after the last infusion. The first cycle consisted of a continuous intravenous (CIV) infusion over 8 weeks. Participants who achieved a Complete Response (CR) or Partial Response (PR) or had stable disease after the first treatment cycle were eligible to receive a second (consolidation) cycle of treatment over 4 weeks, following a 4-week treatment-free interval. After the last treatment cycle, efficacy and survival follow-up visits occurred for up to 24 months from treatment start. Participants who relapsed during the follow-up period may have received an additional 8 weeks of treatment.

Two dose regimens were assessed in this study. Stage 1 comprised 2 dose cohorts. In Cohort 1, the first 6 participants were to receive blinatumomab in a dose-escalating manner: 9 µg/day for the first week, followed by 28 µg/day for the second week, then 112 µg/day for the remaining 6 weeks of treatment during Cycle 1. In Cohort 2, the next 6 participants enrolled were to receive a constant dose of 112 µg/day blinatumomab. Before the initiation of stage 2, a pre-planned data monitoring committee (DMC) meeting was held to assess the safety profile of Cohort 1 and Cohort 2. The dosing regimen with the more favorable benefit-risk profile was to be selected for Cohort 3.

Eligibility Criteria:
Inclusion Criteria:

* Patients with Diffuse Large B-Cell Lymphoma (DLBCL) who are refractory to first or later treatment or have a first relapse or later relapse not eligible for autologous hematopoietic stem cell transplant (HSCT) or relapsed post- autologous-HSCT
* Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2
* Age ≥ 18 years
* Life expectancy of ≥ 12 weeks
* Cerebrospinal fluid (CSF) free of infiltration by DLBCL

Exclusion Criteria:

* History or presence of clinically relevant central nervous system (CNS) pathology as epilepsy, seizure, paresis, aphasia, stroke, severe brain injuries, dementia, Parkinson's disease, cerebellar disease, organic brain syndrome, psychosis
* Current infiltration of CSF by DLBCL
* History of autoimmune disease with potential CNS involvement or current autoimmune disease
* Autologous HSCT within six weeks prior to start of blinatumomab treatment
* Prior allogeneic HSCT
* Cancer chemotherapy within two weeks prior to start of blinatumomab treatment
* Radiotherapy within four weeks prior to start of blinatumomab treatment
* Immunotherapy (e.g., rituximab) within four weeks prior to start of blinatumomab treatment
* Any investigational anti-lymphoma product within four weeks prior to start of blinatumomab treatment
* Treatment with any other investigational product after signature of informed consent
* Known hypersensitivity to immunoglobulins or to any other component of the study drug formulation
* Abnormal laboratory values indicative of inadequate renal or liver function
* History of malignancy other than non-Hodgkin's lymphoma (NHL) within five years prior to start of blinatumomab treatment with the exception of basal cell or squamous cell carcinoma of the skin, or carcinoma "in situ" of the cervix
* Active uncontrolled infection, any other concurrent disease or medical condition that is deemed to interfere with the conduct of the study as judged by the investigator
* Infection with human immunodeficiency virus (HIV) or chronic infection with hepatitis B virus or hepatitis C virus
* Pregnant or nursing women
* Previous treatment with blinatumomab
* Presence of human anti-murine antibodies (HAMA) at screening