Amgen will use CytomX’s Probody™ therapeutics platform to develop new cancer immunotherapies under a collaboration that could generate up to $1.465 billion-plus for CytomX.
Amgen and CytomX have agreed to codevelop a CytomX Probody T-cell-engaging bispecific antibody construct against the epidermal growth factor receptor (EGFR), an oncology target expressed on multiple human cancer types.
CytomX cited preclinical studies showing that its Probody versions of EGFRxCD3 bispecific therapeutics induced tumor regressions and increased the therapeutic window for the cancer target.
“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,” Sean E. Harper, M.D., Amgen EVP of R&D, said in a statement yesterday. “Our collaboration with CytomX leverages Amgen's development leadership in bispecifics and expands our immuno-oncology capabilities with an additional and complementary bispecific technology.”
Amgen and CytomX have agreed to codevelop a Probody T-cell-engaging bispecific against EGFRxCD3, with CytomX overseeing early development and Amgen leading later development and commercialization. Global late-stage development costs will be shared between the companies, Amgen and CytomX said.
“Probody-based T-cell-engaging bispecific antibodies offer significant potential in treating cancers by employing localized therapeutic activity within tumor tissue,” added CytomX president and CEO Sean McCarthy, D.Phil. “Development of Probody-based T-cell-engaging bispecifics further validates the broad applicability of the Probody platform in addressing unmet needs in oncology.”
Amgen has agreed to pay CytomX $40 million upfront, as well as 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.
In addition, 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 ex-U.S. net product sales.
Amgen will also receive exclusive worldwide rights to develop and commercialize up to three additional, undisclosed targets. Should Amgen develop all three, it has agreed in return to pay CytomX up to $950 million in additional up-front and milestone payments, and high single-digit to mid double-digit royalty payments on any resulting products.
Amgen also agreed to give CytomX rights to an undisclosed preclinical T-cell-engaging bispecific program—in return for CytomX agreeing to pay Amgen milestone and royalty payments on any resulting products.
CytomX says its Probody candidates are designed to bind selectively to tumors, but not to healthy tissue, thus minimizing toxicity and creating safer, more effective cancer therapies. The company’s pipeline includes Probody cancer immunotherapies, Probody drug conjugates (PDCs), T-cell-engaging Probody bispecifics, and Probody-enabled chimeric antigen receptor natural killer (ProCAR-NK) cell therapies.
The alliance with Amgen is CytomX’s second billion-dollar-plus immune-oncology collaboration inked this year. In March, CytomX expanded a three-year-old cancer therapeutics partnership with Bristol-Myers Squibb (BMS) to potentially $2.888 billion for the six oncology targets of the eight-target collaboration by paying BMS $200 million upfront and agreeing to add up to eight new candidates. The expanded collaboration ranked second on GEN’s list of Top 10 Immuno-Oncology Collaborations, published in April.