Pfizer said Friday it is asking U.S. regulators to allow emergency use of its COVID-19 vaccine, starting the clock on a process that could bring limited first shots as early as next month and eventually an end to the pandemic -- but not until after a long, hard winter.

The action comes days after Pfizer Inc. and its German partner BioNTech announced that its vaccine appears 95% effective at preventing mild to severe COVID-19 disease in a large, ongoing study.