What Went Wrong With AstraZeneca?

The intense public scrutiny is vaccine safety at work.

The most important thing to know about AstraZeneca’s Covid-19 vaccine is that it’s safe and it works — in spite of the missteps that have marred nearly every stage of its rollout.

New data shared Monday showed the vaccine was 79 percent effective in preventing symptomatic infections in a trial of over 32,000 people, and the company said it would prepare to apply for emergency authorization from the Food and Drug Administration in the coming weeks.

But health officials said Tuesday that the results from the trial may have relied on “outdated information” that “may have provided an incomplete view of the efficacy data.”

AstraZeneca said Tuesday that it plans to announce results from the primary analysis within 48 hours.

The study findings shared Monday briefly boosted confidence in the vaccine after the last week’s disaster for AstraZeneca: As coronavirus cases rose in a third surge across Europe, reports began to emerge that a handful of people who received AstraZeneca’s vaccine experienced rare but serious and unusual blood clotting. More than a dozen nations suspended use of the vaccine. The European Medicines Agency quickly reaffirmed the benefit of getting the vaccine and said the clotting cases would be investigated further.

As AstraZeneca’s drama plays out in public, many public health advocates have watched with horror, afraid they are witnessing the legitimacy of global vaccine development being destroyed. But this process, warts and all, is how vaccine safety is supposed to work. And if the AstraZeneca vaccine deserves people’s confidence after months of stumbles, this process is how it will earn it.