Ken Griffin's Citadel fund significantly increased its stake in pharmaceutical giant Eli Lilly in the second quarter of this year, making it one of the fund's top holdings. Eli Lilly is currently at the center of two major medical trends: obesity and Alzheimer's disease. Its obesity drugs, Mounjaro and Zepbound, contributed approximately $14.8 billion in sales in the second quarter of 2026, driving the company's total revenue up 48% year-over-year to approximately $23 billion. Additionally, Eli Lilly's Alzheimer's drug, Kisunla (donanemab), has received full FDA approval in the U.S. and marketing authorization in Europe. Eli Lilly's stock price has risen from less than $700 to approximately $1,240 over the past year.