AstraZeneca shares take historic tumble on failed lung cancer study By: CNBC.com News July 27, 2017 at 09:12 AM EDT AstraZeneca shares fell 15 percent after disappointing results for a lung cancer treatment in highly anticipated clinical trial. Read More >> Related Stocks: Astrazeneca Plc ADR Bristol-Myers Squibb Merck & Co Pfizer Rogers Corp