Blinatumomab is a novel antibody therapy for the treatment of cancer, inflammation, and autoimmune diseases that activates a patient's T cells to seek out and destroy cancer cells. A recent phase 1 study demonstrated tumor regression, and in some cases, complete remission, in non-Hodgkin's lymphoma patients who relapsed after previous treatments and were considered to have incurable disease. Most of the remissions are reported to continue, with the longest remission ongoing for more than 1 year. Results from this ongoing Phase 1 clinical trial conducted by Micromet, Inc. (R&D Center, Munich, Germany) with the CD19-specific BiTE antibody blinatumomab show that all seven patients treated to date achieved complete or partial responses. The safety profile observed in this study supports continued blinatumomab development.
"These results represent significant progress of a T cell engaging antibody for treatment of lymphoma patients as single agent therapy. We observed tumor regression in patients at serum levels of blinatumomab, which are approximately five orders of magnitude lower than serum levels needed by conventional monoclonal antibodies for achieving a tumor regression in this disease. This may relate to the high anti-tumor activity of cytotoxic T cells recruited by blinatumomab," commented Patrick Baeuerle, PhD, Micromet Senior Vice President and Chief Scientific Officer.
"This first observation of durable objective responses in relapsed, incurable patients indicates the potential blinatumomab and BiTE antibodies in general may have in fighting cancer," added Carsten Reinhardt, MD, Micromet Senior Vice President and Chief Medical Officer.
Typically antibodies cannot engage T cells because T cells lack the appropriate receptors for binding antibodies. Previous attempts have shown the potential of T cells to treat cancer, but the therapeutic approaches tested to date have been hampered by cancer cells' ability to escape recognition by T cells. The use of antibodies that are specifically designed to engage T cells for attacking cancer cells may provide a more effective anti-tumor approach than conventional monoclonal antibodies, which require much higher doses and are typically combined with chemotherapies.
Illustration: Histopathologic image of Hodgkin's lymphoma. Lymph node biopsy. H & E stain. It may represent a mixed cellularity type. –Wikipedia.
Micromet News Release (08/14/08 News Archive)
Medical News Today (08/15/08)
Abstract (Science; Vol. 321, No. 5891, 974-977 (08/15/08))