Pfizer/BioNTech, Moderna Vaccines Take Baby Steps Into Booster Shots

While the commercial position of Pfizer Inc./BioNTech SE’s and Moderna, Inc.’s COVID-19 vaccines would strengthen if it is recommended that people who received the initial two-dose vaccination series of BNT162b2 or mRNA-1273 get boosters, the US Food and Drug Administration’s expansion of the vaccines’ emergency use authorizations to include third shots for certain vulnerable people accounts for only a very small number of patients. But as variants of concern continue spreading, Moderna may have an upper hand, with data showing strong efficacy against the Delta strain, though those results come with certain caveats.

The FDA said late on 12 August that it amended the EUAs for the two vaccines to allow for additional doses in certain immunocompromised people, while the Centers for Disease...