CVS Health CEO Lynch steps down, Joyner named to the post

CVS Health CEO Karen Lynch has stepped down with company shares down 19% and the national drugstore chain struggling.

Lynch will be replaced by David Joyner, who will attempt to steer the health care giant through a worsening environment of rising medical costs.

Joyner most recently served as executive vice president of CVS Health, and president of CVS Caremark.

The company said it now anticipates third-quarter adjusted earnings of $1.05 to $1.10 per share, citing higher-than-expected medical cost trends. Analysts polled by FactSet predict earnings of $1.69 per share.

CVS Health also announced on Friday that Chairman Roger Farah will now be executive chairman.

Shares tumbled more than 12% before the market open.