Amgen and CytomX Therapeutics Announce Strategic Collaboration in Immuno-Oncology

Amgen and CytomX Therapeutics, Inc., have announced that the companies have entered into a strategic collaboration in immuno-oncology.

The companies will co-develop a CytomX Probody T-cell engaging bispecific against the Epidermal Growth Factor Receptor (EGFR), a highly validated oncology target expressed on multiple human cancer types. Probody T-cell engaging bispecifics are antibody constructs capable of directing cytotoxic T-cells in tumor microenvironments. In preclinical studies, CytomX’s Probody versions of EGFRxCD3 bispecific therapeutics induced tumor regressions and increased the therapeutic window for this high potential cancer target.

“Our collaboration with CytomX leverages Amgen’s development leadership in bispecifics and expands our immuno-oncology capabilities with an additional and complementary bispecific technology,” said Sean E. Harper, M.D., executive vice president of Research and Development at Amgen. “EGFR is a particularly compelling target on which to employ the CytomX Probody platform given its potential to localize activity within tumors while limiting potential toxicity.”

“Probody-based T-cell engaging bispecific antibodies offer significant potential in treating cancers by employing localized therapeutic activity within tumor tissue,” said Sean McCarthy, D.Phil., president and chief executive officer of CytomX Therapeutics. “Through this collaboration, we are positioned to combine Amgen’s industry-leading expertise in leveraging bispecifics to activate a patient’s immune-system with CytomX’ ability to design potent new therapies that exploit unique conditions in the tumor microenvironment. Development of Probody-based T-cell engaging bispecifics further validates the broad applicability of the Probody platform in addressing unmet needs in oncology.”

Under the terms of the agreement, Amgen and CytomX will co-develop a Probody T-cell engaging bispecific against EGFRxCD3 with CytomX leading early development. Amgen will lead later development and commercialization with global late-stage development costs shared between the two companies. Amgen will make an upfront payment of $40 million and purchase $20 million of CytomX common stock. CytomX will be eligible to receive up to $455 million in development, regulatory and commercial milestones for the EGFR program. Amgen will lead global commercial activities with CytomX able to opt into a profit share in the U.S. and receive tiered, double-digit royalties on net product sales outside of the U.S.

Amgen will also receive exclusive worldwide rights to develop and commercialize up to three additional, undisclosed targets. Should Amgen ultimately pursue all of these targets, CytomX will be eligible to receive up to $950 million in additional upfront and milestone payments and high single-digit to mid-double digit royalty payments on any resulting products. CytomX will also receive the rights from Amgen to an undisclosed preclinical T-cell engaging bispecific program; Amgen is eligible to receive milestones and royalty payments on any resulting products from this CytomX program.