After PhIII brain cancer vax bust, Celldex looks outward with Kolltan buy

Just eight months ago, small-cap Celldex Therapeutics ($CLDX) saw its shares plunge by two-thirds after its "Breakthrough" brain cancer vax Rintega (rindopepimut) failed to improve overall survival in a key late-stage test. Today, it is brushing off that hit with the acquisition of Kolltan Pharmaceuticals to bolster its pipeline.

The deal, worth $62.5 million upfront with $172.5 million available in biobucks, sees Celldex take hold of the private New Haven, CT-based biotech and its early-stage work on antibody-based drugs targeting receptor tyrosine kinases (RTKs).

Much of the company’s R&D has focused on overcoming tumor resistance mechanisms associated with current tyrosine kinase inhibitors (an aging oncology class), and those seen in patients who have failed other cancer meds.

Its new candidates include KTN0158, a mAb that stops KIT activation in tumor cells and mast cells, which is currently undergoing Phase I tests in refractory gastrointestinal stromal tumors (GIST).

The biotech is hopeful it could be used to treat patents resistant to Novartis’ GIST med Gleevec (imatinib mesylate). Celldex believes this could also work well in combo with its CD27 agonist varlilumab.

When the deal is closed Celldex’s drug pantry will include seven candidates including therapeutic antibodies, antibody-drug conjugates and immune system modulators, as well as two active preclinical programs.

The NJ-based biotech plans to continue work on these drugs both on their own, and in combination with its pipeline candidates.

Anthony Marucci, co-founder, president and CEO of Celldex, said in a statement: “The acquisition of Kolltan provides Celldex with a truly unique platform of antibodies targeting receptor tyrosine kinases which we believe are highly compatible with our pipeline. We believe this acquisition complements our leadership position in immuno-oncology and enhances our ability to develop targeted therapeutic regimens to dramatically improve patient outcomes.”

The market essentially shrugged its shoulders at the deal, with the $310 million market cap co 0.95% at end of play yesterday, but then nudged up 0.3% after hours.