Tuesday, Pfizer said it is asking U.S. regulators to authorize its experimental pill for COVID-19, setting the stage for a likely launch of the promising therapy in the coming weeks. The company’s filing comes as new infections rise again, driven mainly by hot spots in states where colder weather has brought more Americans indoors. In addition, an influential U.S. advisory panel will discuss expanding eligibility for COVID-19 vaccine booster shots to all adults Friday, a move that could make the vaccinations available as early as this weekend.