The collaboration combines CytomX’s Probody technology with Regeneron’s Veloci‑Bi bispecific platform to target hard‑to‑treat tumour types.
Established in 2022, the partnership combines CytomX’s biologic masking technology with Regeneron’s expertise in bispecific antibodies.
The therapies are designed to stay inactive until proteases in the tumour microenvironment activate them, aiming to improve both the safety and effectiveness of T‑cell engager treatments.
This approach seeks to address tumour types that have proven difficult for conventional immunotherapy.
Regeneron oncology and antibody technology research senior vice-president John Lin said: “Cancer necessitates innovative treatment approaches, and with this expanded collaboration with CytomX, we are advancing bispecific treatments where we see the most promise.
“Our complementary oncology expertise with CytomX, including application of our proprietary VelociSuite technologies developed to accelerate drug discovery and development, makes us uniquely suited to work together on this endeavour to bring new medicines to patients in need.”
CytomX CEO and chairman Sean McCarthy said: “Our ongoing research collaboration with Regeneron is based on a shared commitment to cutting-edge science and a vision to push the boundaries of cancer immunotherapy.
“At CytomX, we are applying our deep understanding of masking and protease biology to unlock new opportunities uniquely enabled by our technology.
“Regeneron’s deep expertise in bispecific immunotherapies has made it an ideal partner in expanding the reach of the PROBODY platform, and we look forward to building on our alliance momentum to collectively make a meaningful difference for people with cancer.”
Under the revised terms, the companies will collaborate on the discovery, identification, and validation of conditionally active bispecific antibodies.
Regeneron will fund preclinical, clinical, and commercial activities. CytomX will receive a $37m target nomination payment for two newly selected targets, and Regeneron has the option for up to six future targets.
CytomX remains eligible for global net sales royalties and further milestone payments.
Last month, Regeneron signed a $2.32bn research collaboration with Parabilis Medicines to develop therapeutic candidates leveraging the latter’s Helicon peptide platform, with an emphasis on antibody-Helicon conjugates.