The collaboration includes molecular engineering by Xencor and the preclinical development of bispecific molecules for five programs proposed by Amgen, leveraging XmAb bispecific Fc domains to make half-life extended T cell engagers and dual targeting bispecific antibodies. The agreement also includes a preclinical bispecific T cell engager program directed at CD38 and CD3 for multiple myeloma.
Amgen will be fully responsible for preclinical and clinical development and commercialization worldwide. Under the terms of the agreement, Xencor will receive a $45 million upfront payment and up to $1.7 billion in clinical, regulatory and sales milestone payments in total for the six programs. Xencor is eligible to receive mid to high single-digit royalties for candidates directed against Amgen's targets, and high single to low double-digit royalties for Xencor's CD38 bispecific T cell engager.
"We are pleased to be joining forces with Xencor to expand our immuno-oncology and inflammation position by leveraging Amgen's antibodies and Xencor's bispecific antibody platform," said Sean E. Harper, M.D., executive vice president of Research and Development at Amgen. "We are especially excited about the T cell engaging bispecific antibody directed against CD38, which complements Amgen's BiTE® platform, while growing our hematology and oncology portfolio that includes two bispecific T cell engager antibodies, BLINCYTO® (blinatumomab) and AMG 330, as well as Kyprolis® (carfilzomib) for relapsed multiple myeloma."
Bispecific technologies seek to engineer monoclonal antibodies to bind two unique drug targets, as opposed to traditional antibodies designed to bind to a single antigen target. This approach represents a powerful opportunity in immuno-oncology to simultaneously engage immune cells and tumor cells to localize anti-tumor immune activity where it is needed most.
"Amgen, which has pioneered the use of bispecific antibodies, has chosen to access our XmAb bispecific technology for its robustness, long half-life, and the plug and play ease-of-development of our platform," said Bassil Dahiyat, Ph.D., president and chief executive officer of Xencor. "This opportunity expands the reach of our technology with a partner that has proven experience in bispecifics and immuno-oncology. Xencor will continue to focus on its internal programs including its immuno-oncology XmAb bispecifics, XmAb14045 in acute myeloid leukemia and XmAb13676 in B-cell malignancies, which are expected to enter clinical development in 2016."
About Xencor's XmAb® Bispecific Technology
As opposed to traditional monoclonal antibodies that target and bind to a single antigen, bispecific antibodies are designed to elicit multiple biological effects that require simultaneous binding to two different antigen targets. Xencor's XmAb bispecific Fc domain technology is designed to maintain full-length antibody properties in a bispecific antibody, potentially enabling favorable in vivo half-life and simplified manufacturing.
Efforts at bispecific antibody design are typically frustrated by poor molecular stability, difficulties in production and short in vivo half-life. Xencor has engineered a series of Fc domain variants that spontaneously form stable, heterodimeric bispecific antibodies and that can be made and purified with standard antibody production methods. These bispecific Fc domains are used to generate a broad array of novel drug candidates in a range of molecule formats.
Xencor's initial bispecific programs are tumor-targeted antibodies that contain both a tumor antigen binding domain and a cytotoxic T-cell binding domain (CD3 binding domain). These bispecific antibodies activate T cells at the site of the tumor for highly potent killing of malignant cells. The XmAb Fc domain format allows Xencor to tune the potency of the T-cell killing, potentially improving the tolerability of tumor immunotherapy. Xencor plans to begin clinical testing for two internal programs, XmAb14045 and XmAb13676, in 2016.
About Xencor Inc.
Xencor is a clinical-stage biopharmaceutical company developing engineered monoclonal antibodies for the treatment of asthma and allergic diseases, autoimmune diseases and cancer. Currently, eight candidates that have been engineered with Xencor's XmAb® technology are in clinical development internally and with partners. Xencor's internally-discovered programs include: XmAb5871, which completed a Phase 1b/2a clinical trial for the treatment of rheumatoid arthritis and is in preparation for a clinical trial in IgG4-related disease in 2015; XmAb7195 in Phase 1a development for the treatment of asthma; and XmAb5574/MOR208 which has been licensed to Morphosys AG and is in Phase 2 clinical trials for the treatment of acute lymphoblastic leukemia and non-Hodgkin's lymphoma. Xencor's XmAb antibody engineering technology enables small changes to the structure of monoclonal antibodies resulting in new mechanisms of therapeutic action.
About Amgen
Amgen is committed to unlocking the potential of biology for patients suffering from serious illnesses by discovering, developing, manufacturing and delivering innovative human therapeutics. This approach begins by using tools like advanced human genetics to unravel the complexities of disease and understand the fundamentals of human biology.
Amgen focuses on areas of high unmet medical need and leverages its biologics manufacturing expertise to strive for solutions that improve health outcomes and dramatically improve people's lives. A biotechnology pioneer since 1980, Amgen has grown to be one of the world's leading independent biotechnology companies, has reached millions of patients around the world and is developing a pipeline of medicines with breakaway potential.