Bloomberg reports that the chief executive of BioNTech said that German pharmaceutical company is confident that its coronavirus vaccine works against the new UK variant, but further studies are need to be completely sure.

“We don’t know at the moment if our vaccine is also able to provide protection against this new variant,” Ugur Sahin told a news conference the day after the vaccine was approved for use in the European Union. “But scientifically, it is highly likely that the immune response by this vaccine also can deal with the new virus variants.”

Sahin said that the proteins on the UK variant are 99% the same as on the prevailing strains, and therefore BioNTech has “scientific confidence” that its vaccine will be effective.