CytomX in deal that could earn it nearly $1.5 billion

US biotech CytomX Therapeutics’ (Nasdaq: CTMX) shares soared more than 41% to $26.81 in after-hours trading on Tuesday, after it announced a second lucrative collaboration with a fellow US biotech company, this one with the potential to bring in $1.5 million in upfront and contingent payments.

CytomX has entered into a strategic collaboration in immuno-oncology with Amgen (Nasdaq: AMGN), whereby 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. Amgen’s shares were virtually unchanged.

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.