Good news for some companies often means bad news for others. That's what we're seeing Friday as the stocks of several COVID-19 vaccine makers sank following the announcement by Merck (NYSE: MRK) and Ridgeback Biotherapeutics of positive results from a late-stage study of an oral COVID-19 treatment.
Shares of Pfizer (NYSE: PFE) were down by 1.6% as of 11:20 a.m. EDT after having declined by as much as 3.1% earlier in the session. Pfizer's COVID vaccine partner, BioNTech (NASDAQ: BNTX) , fared even worse, with its stock sliding by 11.9%.
A couple of companies that have COVID-19 vaccine candidates that aren't on the market yet also felt the sting of the news from Merck and Ridgeback. Novavax (NASDAQ: NVAX) stock was trading 17% lower, while shares of Vaxart (NASDAQ: VXRT) dropped by 12.3%.
For further details see:
Why Pfizer, BioNTech, Novavax, and Vaxart Stocks Are Sinking Today