Pfizer breaks off a 5-year, $635M collaboration deal with CytomX, with nothing to show for it

After lining up a couple of big biopharma collaborations with large upfront payments in 2017, CytomX $CTMX is getting this year started by bidding one of its first Big Pharma partners so long.

Sean McCarthy,CytomX CEO

The South San Francisco-based biotech says that Pfizer $PFE notified them yesterday that they are dropping out of the Probody deal, discarding its latest two targets after dumping the first on EGFR and never going after the fourth. The deal, which started out with a $25 million upfront payment and a large $610 million package of milestones, had helped validate CytomX’s platform tech on armed antibodies. Pfizer was looking for safer versions of Erbitux and Vectibix.

CytomX scored $60 million in upfront cash when Amgen signed up for a $1.5 billion deal last fall. And that came after Bristol-Myers Squibb forked over $200 million in cash to get the biotech focused on a safer, better CTLA-4 to eventually succeed Yervoy.

Amgen $AMGN jumped in for a T-cell engaging bispecific targeting the Epidermal Growth Factor Receptor (EGFR), a high-value target expressed on multiple cancer types. They’re building on the biotech’s preclinical work on an EGFRxCD3 program.