AstraZeneca’s late-stage trial failure sends its shares down 16% and Bristol-Myers, Merck stocks seesawing By: MarketWatch July 27, 2017 at 08:43 AM EDT The three pharmaceutical companies are competing to be leaders in treating lung cancer. Read More >> Related Stocks: Astrazeneca Plc ADR Bristol-Myers Squibb Merck & Co Standard & Poors 500