Long-term CVS Health Chief Executive David Joyner has replaced Karen Lynch as CEO as the company struggles to deliver higher profits and stock performance, CVS announced Friday.

The move takes effect Thursday, the day before the announcement, as CVS shares have fallen nearly 20% this year. Shares fell about 11% in premarket trading on Friday.

CVS has faced challenges as higher medical costs weigh on its Aetna insurance unit and consumer spending declines at its retail pharmacies. In August, the company cut its full-year profit forecast and said it would cut costs by $2 billion over the next few years.

In its press release Friday, CVS said it expects third-quarter adjusted earnings to be between $1.05 and $1.10 per share. It expects medical costs to be higher than previously expected, with a so-called medical benefit ratio of 95.2% in the quarter.

Joyner most recently led the company's pharmacy services business as president of CVS Caremark, a position similar to Lynch, before taking the top job in February 2021.

Lynch also resigned from the company's board this week, the company said Friday. Joyner will take a seat on the board and Chairman Roger Farah will assume the role of Executive Chairman.

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