Remarkable Vaccine Results Leave a Lot of Questions Unanswered

When Pfizer Inc. and BioNTech SE reported their successful coronavirus vaccine trial results on Nov. 9, the news sparked optimism around the globe that there was finally light at the end of the long, dark tunnel. Investors rushed to bid up stocks—not just those of vaccine makers, but of a wide swath of ordinary companies expected to benefit once the pandemic moves into the rearview mirror. Yet there are still many hurdles before vaccines get into widespread use and Covid-19 is history.

Questions about production, distribution, and, most important, the capability of the shot itself still need to be answered. Pfizer’s late-stage trial started less than four months ago, and how long the vaccine will confer protection is unknown. “The key question still centers upon time,” says Michael Kinch, a drug development expert and associate vice chancellor at Washington University in St. Louis. “Will time tell us that the protection remains useful for the larger population?”