Speed Reads

a lot more to learn

What Pfizer's scientists consider the 'biggest surprise' about their COVID-19 vaccine

The aspect of Pfizer's coronavirus vaccine that really stunned the company's scientists was the fact that vaccinated participants in the Phase 3 efficacy trial had protections against the pathogen by day 12, a time at which there was barely any antibody response, Stat News reports. "That was the biggest surprise," said Vidia Roopchand, Pfizer's principal scientist for viral vaccines.

Roopchand is still trying to figure exactly why that is — not that it's a bad thing — by poring over the data. One possibility is that other aspects of the immune system such as T-cells that Roopchand says have largely been neglected in immunology research may have played a significant role. It's possible, he suggested, that's more important to measure cellular immunity than look for a robust antibody response. "The 12-day protection data is telling us there's more to it," Roopchand told Stat. "This is a great time to learn."

He also indicated that the discovery could affect future vaccine development, regardless of the virus. Before, vaccine candidates would likely get tossed to the side if they didn't produce a strong antibody response in animal testing, but a deeper look at the rest of the immune system could change that approach. Read more at Stat News.