- Expanded collaboration builds upon research momentum in developing next-generation bispecific immunotherapies using CytomX's PROBODY® and Regeneron's Veloci-Bi® platforms -

- CytomX to receive $37 million target selection payment for two additional programs selected -

- Regeneron secures option to select up to 6 additional future targets bringing total potential target nomination, research, development, regulatory and sales-based milestones covered under the collaboration to up to approximately ~$4 billion -

SOUTH SAN FRANCISCO, Calif., June 03, 2026 (GLOBE NEWSWIRE) -- CytomX Therapeutics, Inc. (NASDAQ:CTMX) today announced an expansion of its collaboration and licensing agreement with Regeneron Pharmaceuticals, Inc. to create conditionally-activated bispecific cancer therapies utilizing CytomX's Probody® therapeutic platform and Regeneron's Veloci-Bi® bispecific antibody development platform.

The Regeneron and CytomX collaboration, initially entered into in 2022, is strategically focused on applying CytomX's biologic masking strategies in combination with Regeneron's bispecific antibodies to develop investigational bispecifics that remain inactive until activated by proteases in the tumor microenvironment. This technology has the potential to widen the therapeutic window and help minimize off-target effects for next-generation T-cell engaging therapies, potentially addressing tumor types that have historically been challenging for immunotherapy.