Modern Shares Inc. and BioNTech SE fell sharply as vaccine makers saw the worst day on the stock market in late November.
The main US Covid-19 vaccine manufacturers sank on Tuesday, as Moderna fell 9% and BioNTech fell 5.5%. These declines, along with Pfizer Inc.’s 1.7% decline, wiped out the combined $ 10 billion market value.
Biotech stocks, which have been popular with retailers, are some of the most volatile stocks on the market, and the two vaccine manufacturers were no exception – average daily price fluctuations for both stocks were more than 3 times higher. larger than those of the wider market.
The declines came after health officials said the new Covid-19 variant that appeared in the UK could already be in the US, Germany, France and Switzerland. So far, there have been no indications that the companies’ blows will not work against the evolving strain. BioNTech says its vaccine will likely be effective in inoculating against the new strain of virus discovered in the UK, testing against the new variant should take about two weeks. This echoed some of the the positive sentiment expressed by European regulators on Monday.
Read more: BioNTech to increase capacity, see the vaccine beating a new strain

An analyst Morgan Stanley also considered that the current vaccine crop is likely to be protective, but said that if it did not exist, there are still some benefits – at least for investors.
“If current vaccines are not protective, it would be a severe obstacle for society, but it would extend the sustainability of vaccine manufacturers’ sales,” wrote David Risinger, an analyst at Morgan Stanley in a customer note. He added that vaccines could be effective against a new strain.
This year’s individual investors have helped strengthen biotechnology companies pursuing Covid-19 products, although interest in marketing has declined. Moderna, BioNTech and Pfizer have each changed their minds, as the vaccines have received regulatory approval.
Tuesday’s slide puts a small imprint on a rally that has pushed Moderna’s stock to more than sixfold so far this year, while BioNTech has nearly tripled in value.
– With the assistance of Brandon Kochkodin and Divya Balji
(Updates with closing prices.)