Pfizer data suggests COVID-19 shot protects against SA variant

Citing updated trial data, Pfizer and BioNTech also say their vaccine is 91 percent effective at preventing COVID-19.

Pfizer Inc and BioNTech said new clinical trial data signalled that their COVID-19 vaccine could protect against the new coronavirus variant first discovered in South Africa. The shot was 100 percent effective in preventing illness among trial participants in South Africa, where the new B1351 coronavirus variant is dominant, the companies said. The South Africa trial was relatively small, with 800 participants. Pfizer said the rate was derived from a relatively small number of nine infections observed, all in the placebo group.