What happened
While the latest news about BioNTech (BNTX 0.55%) was generally positive, investors didn't greet it warmly on Wednesday. The German biotech's shares fell by nearly 4% on the day.
So what
Pfizer (PFE 0.23%), BioNTech's partner in the development of top coronavirus vaccine Comirnaty, issued an update that morning on the jab. It was a good news/bad news update, with the good being that a booster dose of the vaccine managed to neutralize the omicron variant of the coronavirus in an initial lab study.
Image source: Getty Images.
The bad news was that those inoculated only with the initial two-dose regime of the Pfizer/BioNTech shot might not be sufficiently protected against the fast-spreading variant.
Nevertheless, the pharmaceutical sector giant wrote hopefully, "as the vast majority of epitopes targeted by vaccine-induced T cells are not affected by the mutations in Omicron, the companies believe that vaccinated individuals may still be protected against severe forms of the disease and are closely monitoring real world effectiveness against Omicron, globally."
Investors seem to be troubled by the latter finding, as Pfizer stock also traded down (by 0.6%) on Wednesday, which was a generally upbeat day for the market.
Now what
BioNTech is more susceptible to perceived negative developments with Comirnaty because, so far, it's the company's only commercialized product. Pfizer, meanwhile, is a huge company with a great many goods on the market.
But bear in mind that Comirnaty has been shown to be highly efficacious and a go-to vaccine in many jurisdictions around the world. Here in the U.S., it's still the only coronavirus jab fully approved by the Food and Drug Administration for use. (Two others have received Emergency Use Authorization, but not full approval.)
