Pascal Soriot, former COO of Roche, will take over as CEO of AstraZeneca in October. He will fill the spot vacated by David Brennan, who quit the job in June amid drug development setbacks and growing shareholder discontent.

Soriot takes over from interim CEO Simon Lowth, stepping in at a time when AstraZeneca is struggling to regain ground amid declining sales and troubles advancing experimental drugs for depression and type 2 diabetes.

At Roche, Soriot served as CEO of Genentech and later as COO of the company’s global pharmaceuticals division. He has worked in senior management roles in the United States, Asia, and Europe. Before joining the pharmaceutical industry in 1986, Soriot, who holds an MBA with a major in finance from HEC Paris, practiced as a veterinarian.

Soriot joins the U.K.-based company as sales and profits are sliding. AstraZeneca’s second quarter 2012 sales fell 21 percent while profits were down 33 percent before taxes. The company is facing down the expiration of patent protection on branded products accounting for 44 percent of its sales through the end of 2014. Both the antipsychotic Seroquel and the acid reflux disease drug Nexium have lost patent protection.

“No one is blind to the challenges that confront the pharmaceutical sector and this company,” says Soriot. “But the underlying strengths of AstraZeneca in delivering on its strategy are clear. AstraZeneca will continue to make a positive difference to patients over the longer term and I’m looking forward to playing my part in shaping that future.”

Although Brennan emphasized the importance of innovative collaborations to find ways to develop new treatments during his tenure, shareholders and analysts have pushed the company to make more significant acquisitions to help replenish its drug pipeline. Responding in April, the company acquired Ardea Biosciences and its late-stage gout drug for $1.3 billion. In July it acquired a portfolio of neuroscience assets from Link Medicine and took part in a complex deal with Bristol-Myers Squibb to protect its share of profits of Amylin’s sales of drugs to treat type-2 diabetes, including Byetta.

Soriot will have a good opportunity to steer the company’s next moves. AstraZeneca is bringing him on just in time for its annual strategic review.