Pfizer announced more results in its ongoing coronavirus vaccine study that suggest the shots are 95% effective.

The company also said that the vaccine appears to protect older people most at risk of dying from COVID-19. The surprise announcement, just a week after it first revealed promising preliminary results, comes as the company is preparing within days to formally ask U.S. regulators to allow emergency use of the vaccine.

With Wednesday’s announcement, the company now has accumulated 170 infections in the study and 162 of those were in volunteers who got a dummy shot.