Pharma's big movers: Amylin up on obesity drug, Hep C drug lifts Vertex

News that Amylin Pharmaceuticals (AMLN) inked a billion-dollar development deal with Takeda Pharmaceutical for new obesity therapies was among the favorable developments in the sector on Monday that pushed several key stocks higher. Amylin shares were up nearly 10 percent in late trading after Japan's Takeda said it would pay the San Diego company an upfront payment of $75 million for its anti-obesity compounds and could offer additional payments ultimately exceeding $1 billion.

Among the other big movers, Vertex Pharmaceutical (VRTX) shares advanced more than 8 percent in late trading after a report over the weekend that middle-stage trials of its telaprevir-based treatment for the hepatitis C virus showed more than 80 percent of patients achieved a "sustained viral response," meaning the drug removed the virus from their bodies.