Regeneron has expanded its research alliance with CytomX Therapeutics, paying $37 million to work on conditionally active bispecifics against two targets and secure options on more programs. The expansion swells the potential value of the deal to about $4 billion.
CytomX partnered with Regeneron in 2022. Back then, Regeneron paid $30 million upfront to develop candidates based on its bispecific antibody development platform and CytomX’s technology for keeping molecules inactive until they reach the tumor microenvironment. The deal featured up to $800 million in milestones, plus up to $1.2 billion in further paydays tied to expanding the collaboration.
The expanded agreement goes beyond the scope envisioned in 2022. As well as adding two targets to the collaboration, Regeneron has secured the option to partner with CytomX on up to six more targets. Tallying up target nomination fees and R&D, regulatory and commercial milestones brings the potential value of the deal up to about $4 billion.
Securing the expanded deal, which is roughly double the maximum value of the original agreement, may soften the blow of recent actions by other CytomX collaborators. Last month, Astellas and Bristol Myers Squibb terminated agreements with the biotech after opting against further development of preclinical drug candidates, ending alliances that were worth billions in milestones when first signed.
The axing of the deals with Astellas and BMS followed Moderna’s decision to pause work with CytomX and Amgen’s termination of its license to programs. CytomX’s alliance with Moderna is paused pending future alignment with the mRNA specialist. The Amgen alliance is limited to a candidate that CytomX is developing.
CytomX landed the deals based on the potential of its technology to reduce the binding of biologics until they reach patients’ tumors. By stopping drugs from engaging receptors in healthy tissue, the platform could limit on-target, off-tumor toxicity and expand the therapeutic window. Yet efforts to validate the idea have stuttered, with BMS axing a masked successor to Yervoy after a phase 1/2 trial.
With $346.7 million in cash and two clinical programs, CytomX has the means to generate evidence that the technology works. The biotech’s cash runway, which extends into at least the second half of 2028, covers (PDF) several potential milestones, including the start of a registrational trial of a masked antibody-drug conjugate and phase 1 data on the other clinical candidate.