Pfizer's (NYSE: PFE US) experimental COVID-19 antiviral pill can cut the risk of ending up in the hospital or dying by 89%, and this means that Americans may soon have a choice in COVID-19 pills that they can take at home. The news sent shares of Pfizer soaring 10,9% in trading on Friday, capping off a week in which the company reported better-than-expected sales of its COVID-19 vaccine and its oral COVID-19 pill produced compelling results in a clinical trial.