Pfizer’s PFE proposed acquisition of Seagen SGEN, which develops cancer treatments, for $43 billion indicates that the legacy drugmaker is focused on shoring up its oncology business. Pfizer said Monday it plans to pay $229 per share in cash for Seagen, whose stock soared more than 15% in trading on Monday afternoon. Pfizer’s shares gained about 1.7%. “[Seagen’s]…
