NEW YORK — Jeff Kindler had been Pfizer Inc.'s new CEO all of three days in July when a court ruling shaved one year off the patent life of the company's best-selling drug, Lipitor. The same day, Pfizer was hit with a patent infringement suit on a soon-to-be-launched diabetes drug touted as a blockbuster. The challenges confronting Kindler are mounting quickly, but he's acting swiftly to make changes at the world's largest drugmaker. Earlier this week, barely three weeks into his tenure, he announced a new executive leadership team, which includes one of his competitors for the top spot. He also announced the other contender for the post will leave Pfizer early next year. .