CNBC Exclusive: Eisai U.S. CEO on Alzheimer's drug approval

CNBC's Meg Tirrell talks to Ivan Cheung, Eisai U.S. CEO on the company's Alzheimer's drug receiving approval from the FDA today. With CNBC's Tyler Mathisen and the Fast Money traders, Tim Seymour, Bonawyn Eison, Steve Grasso and Jeff Mills.