AstraZeneca CEO David Brennan will step down from the company following a dramatic fall in profits in the first quarter.
The drug maker's earnings per share fell 19% while revenue for the first quarter was $7.3 billion, down 11% from figures reported in the same period last year.
Loss of exclusivity on several key brands accounted for 8% of the revenue decline.
In March, AstraZeneca lost its battle to delay generics of its antipsychotic Seroquel as its patent of the drug expired.
The UK-based company also faces losing US protection of its heartburn pill Nexium and its top-selling heart drug Crestor in 2014 and 2016, respectively.
The company anticipates a rebound in the remaining three quarters, but said in a statement that achieving double-digit growth for the full year may be a challenge.
Brennan said, "The anticipated impact from the loss of exclusivity on several brands, together with challenging market conditions, has made for a difficult start to the year in revenue terms. Delivery on our restructuring plans and continued discipline on operating costs, together with the benefits from a lower tax rate, will only partially mitigate the revenue pressures."
Brennan will step down from the company in June after six years in charge.
Executive director and CFO Simon Lowth will act as interim CEO from June 1 until a replacement is found.
Image: AstraZeneca CEO David Brennan will step down from his role in June. Credit: AstraZeneca.