CytomX Therapeutics, Inc. announced the selection of a third target by Bristol-Myers Squibb in accordance with the companies' strategic oncology collaboration established in May 2014, triggering a $10 million milestone payment. Investigational therapeutics developed with CytomX's Probody platform are designed to be active in the tumor while sparing healthy tissue. By restricting activity to the tumor microenvironment, investigational Probody therapeutics directed against both validated and novel targets have been shown preclinically to enable anti-tumor efficacy with an enhanced safety window, relative to traditional antibody-based therapies.

Under the terms of the agreement which was entered into in May of 2014, CytomX granted Bristol-Myers Squibb exclusive worldwide rights to develop and commercialize Probodies for up to four oncology targets including CTLA-4, a clinically validated immune inhibitory checkpoint receptor. Bristol-Myers Squibb made an upfront payment of $50 million to CytomX in 2014 and provides research funding over the course of the research term. Upon the selection of the third and fourth targets, Bristol-Myers Squibb pays CytomX selection payments.

CytomX is also be eligible to receive additional preclinical payments and up to $298 million in future development, regulatory and sales milestone payments for each collaboration target, as well as tiered mid single-digit rising to low-double digit royalty payments on net sales of each product commercialized by Bristol-Myers Squibb.