Antibody companies tend to follow a similar partnering strategy - starting with service deals to generate candidate therapeutics against a collaborator's targets, then graduating to product deals for internally developed candidates. What's less common, however, is for the product deal to be with another antibody platform company. But that's exactly what happened in last month's deal between Xencor Inc. and MorphoSys AG, a partnership that provides a clear illustration of where each company is in its life cycle, and signals a new stage of maturation for both antibody plays.

Xencor granted MorphoSys exclusive, worldwide rights to develop and commercialize XmAb5574 (now called MOR208). The humanized mAb against CD19 is entering Phase I testing to treat chronic lymphocytic leukemia (CLL). Xencor will receive $13 million up front and is eligible for undisclosed milestones, plus tiered royalties.