Pfizer Course May Have 23% Efficacy Vs. Omicron: Study (1)

A two-shot course of Pfizer Inc.’s vaccine may have just 22.5% efficacy against symptomatic infection with the omicron variant, but can thwart severe disease, according to laboratory experiments in South Africa.

Researchers at the Africa Health Research Institute in Durban issued additional data on a small study released earlier this week from which they made an estimate of the efficacy of the vaccine using modeling.

The research considered blood plasma samples from 12 participants. Scientists found omicron resulted in about a 41-fold reduction in levels of neutralizing antibodies produced by people who had received two doses of the Pfizer- ...