Actelion, Europe's largest biotech company which has been under pressure from activist investor Elliott Advisors, is changing its management structure, including appointing a chief operating officer.

Actelion said in a statement it had appointed Otto Schwarz, head of business strategy and operations at Actelion since 2008, as COO, allowing Chief Executive Jean-Paul Clozel to focus more on strategic matters.

"Together, we are committed to move Actelion to the next stage: advancing value creation for all stakeholders by turning innovation into successful medicines that change patients' lives," Clozel said. "We will also continue to evaluate in-licensing and acquisitions and act decisively when we identify value-adding opportunities."

Actelion also said it was changing its executive committee to strengthen leadership and governance, which had been among Elliott's demands before shareholders rejected a bid for control by the hedge fund last month.

 In addition to Clozel and Schwarz, the core executive committee would be made up of Chief Financial Officer Andrew Oakley, Head of Global Clinical Development Guy Braunstein and Chief Business Development Officer Nicholas Franco. New York-based hedge fund Elliott had urged the Swiss biotech group to consider seeking a buyer after a string of product setbacks and accused Actelion of pursuing a high-risk strategy that has eroded shareholder value.