Covid-19: Sinovac vaccine shows 78% efficacy in Brazil after data confusion

The vaccine developed by China’s Sinovac Biotech Ltd. was found to be 78% effective against Covid-19 in late-stage trials in Brazil, the most definitive evidence so far on the shot’s efficacy after previous data sparked doubt and confusion.
 

The protection rate, confirmed by Sao Paulo state officials, was derived from Sinovac’s most advanced final-phase trials in Brazil involving about 13,000 participants. Coming after data was withheld at a progress update in late December, the rate is still below the roughly 95% effectiveness seen in cutting-edge mRNA vaccines developed by Pfizer Inc. and Moderna Inc. and being deployed in the U.S.

Sinovac’s