Xencor, Inc., a bio-therapeutics company developing protein and antibody therapeutics, extended its research collaboration with Roche to create monoclonal antibodies with differentiated pharmacological profiles. Roche and Xencor entered into an initial collaboration in January 2005, in which Roche applies Xencor's XmAb Fc domains with the aim of enhancing the therapeutic efficacy of an antibody against a cancer target. With this extension, Roche can further its research efforts against such target.

Under the original collaboration, Xencor received technology access and license fees, and is eligible to receive additional license fees, milestones and royalties in the event that Roche advances candidates into development. Xencor will receive additional fees for the extension. Specific financial terms were not disclosed.

"We are very pleased to continue working with Roche to apply our XmAb proprietary engineered Fc domains to enhance the efficacy of Roche's proprietary antibodies," said Bassil Dahiyat, President and CEO of Xencor.

Xencor's XmAb engineered Fc domains are designed to enhance the therapeutic properties of monoclonal antibodies and form a leading proprietary position in Fc engineering. Xencor's Fc domains can be inserted into antibody candidates against any target antigen and may improve one or more important effector functions, including enhanced antibody-mediated tumour cell killing, sustained half-life and increased structural stability. XmAb antibodies are produced using conventional expression and manufacturing processes. Xencor is creating a pipeline of XmAb antibody drug candidates with enhanced potency and pharmaceutical properties.