LONDON, April 26 (Reuters) - AstraZeneca Chief Executive David Brennan is to step down on June 1 in an abrupt exit that follows rising investor discontent at the company's performance.
Underlying earnings fell 19 percent in the first quarter, underscoring the drug company's need to find new sources of growth as key products lose patent protection.
Britain's second-biggest drugmaker has recently stepped up its pace of deal-making, to bring in more promising new drugs from other companies, but Brennan has been under fire from some investors for not acting sooner.
AstraZeneca faces a slump in sales, following the loss of patent cover on antipsychotic Seroquel last month, while heartburn pill Nexium and its top-selling heart drug Crestor lose U.S. protection in 2014 and 2016, respectively.
Although the main hit from the loss of Seroquel is yet to come, group sales already fell 11 percent in the first three months, weighed down by a tough year-ago comparison and generic competition for Nexium and other drugs in Europe.
Sales in the quarter were $7.35 billion, generating "core" earnings, which exclude certain items, down 19 percent at $1.81 a share.
Analysts, on average, had forecast sales in the quarter of $7.92 billion and earnings of $1.79 per share, according to Thomson Reuters I/B/E/S.