Sanofi, GSK say COVID-19 vaccine won't be ready until late 2021

Drugmakers GlaxoSmithKline and Sanofi say their potential COVID-19 vaccine won't be ready until late next year as they seek to improve the shots effectiveness in older people. The companies said Friday that early-stage trials showed the vaccine produced an insufficient immune response in older adults, demonstrating the need to refine the product so it protects people of all ages. They said they now expect the vaccine to be available in the fourth quarter of 2021.

GSK and Sanofi, based in London and Paris, respectively, said they were confident of the vaccines ultimate success due to positive results from other tests.

In adults 18 to 49, the vaccine produced an immune response comparable to patients who had recovered from COVID-19, the companies said. In addition, they reported positive results from a challenge study in which non-human primates were intentionally exposed to the virus.