Pfizer Won the Vaccine Race. Was There a Downside?
The Delta variant’s arrival this summer delivered a blow to the nation’s entire coronavirus arsenal, but its impact on the champion of last year’s vaccine race—Pfizer—has been particularly humbling. Compared with Moderna’s competing shot, Pfizer’s vaccine seems to induce half the amount of virus-fighting antibodies, and is associated with nearly twice as many breakthrough infections, […]