‘Crazy Fast’ Vaccine Race Has Drug Companies Pushing Their Limits

On March 16, just two months after researchers deciphered the genetic code of the coronavirus that causes Covid-19, Moderna Inc.’s vaccine began human trials. Now, no less than four Covid vaccines are hurtling toward the finish line in the U.S. Moderna and Pfizer Inc., along with its German partner BioNTech SE, are leading the pack with vaccines that require two doses, while a single-shot vaccine from Johnson & Johnson began a late-phase trial last week. “This is beyond unprecedented,” says Otto Yang, a viral immunologist at UCLA. “It is crazy fast.”

There may never have been anything like this pedal-to-the-metal race in the history of vaccines. But will they work? And will enough people take them, especially amid the political turmoil surrounding their development?