ImmunoGen plummets as its Roche-partnered cancer drug comes up short

ImmunoGen ($IMGN) watched its shares fall by 50% when partner Roche ($RHHBY) revealed disappointing results for the pair's targeted cancer drug, casting doubts on the biotech's technology for creating armed antibodies. In a three-armed Phase III trial, Roche tested a combination of its own Perjeta and the ImmunoGen-partnered Kadcyla against Kadcyla alone and Herceptin in patients with HER2-positive breast cancer, finding that all three charted similar results in progression-free survival. That's bad news for Roche and its hopes of unseating the soon-to-come-off-patent Herceptin, and it was particularly damaging for ImmunoGen, whose antibody-drug conjugate technology is meant to make Kadcyla a more effective therapy. More | Read FiercePharma's coverage