Marc Tessier-Lavigne, the former president of Stanford University who resigned last year after questions arose about his scientific research, has a new job as chief executive officer of a drug development startup. The company, Xaira Therapeutics, launched this week with $1 billion in capital commitments from some of Silicon Valley’s biggest firms, including Sequoia Capital and Lightspeed Venture Partners. The company aims to use artificial intelligence models to find new drugs to treat diseases....