German chemicals firm Merck will soon have a new chief executive officer (CEO) after the appointment of Karl-Ludwig Kley to the title. Kley, who currently serves as vice chairman of the board, will succeed current CEO Michael Roemer at the end of April. Roemer, who reportedly did not want the CEO's position, will become a member of the board of Merck's biggest shareholder E. Merck OHG. The move comes at a time when Merck is tasked with the integration of Swiss biotech heavy, Serono, which it bought in September for $13.5bn (€10.6bn). Kley has led the integration team since joining from Deutsche Lufthansa at the time of the purchase. "His knowledge of the industry, as well as his achievements as the architect of our new pharmaceutical division Merck Serono, make him the ideal person for this position," said Frank Stangenberg-Haverkamp, chairman of the board of partners of E. Merck OHG. In the last week, drug giant Pfizer has announced the appointment of Constance Horner to serve as lead director of the company's Board of Directors. Horne, who also serves as chair of the board's Corporate Governance Committee, will succeed Dr. Stanley Ikenberry when he retires in March. In this new role, "Horner will preside over executive sessions of Pfizer's independent directors and will facilitate information flow and communication between the directors and the chairman, in addition to other duties specified by the board," said the firm in a statement. Meanwhile, as of this week, Sanofi-Aventis welcomes Tim Rothwell to the role of chairman of Sanofi-Aventis' US Pharmaceutical Activities. He will now have direct responsibility for communications and government policy for Sanofi's operations in the US and abroad, said the firm. At the same time, Greg Irace, who had been serving as chief financial officer (CFO) and senior vice president of Finance & Administration, has been promoted to Rothwell's former position of president and CEO of US Pharmaceutical Operations. In other developments, Wyeth said it has advanced Joseph Mahady to the post of president of Global Business, Wyeth Pharmaceuticals and senior vice president of Wyeth. In his new role, Mahady "assumes operational responsibility for Wyeth's global pharmaceutical business, including Europe/Middle East/Africa, Asia/Pacific, and Wyeth Nutrition, in addition to his current responsibilities for the Americas and the four strategic Global Business Units - Pharmaceuticals, BioPharma, Vaccines and Women's Health Care," said Wyeth. He will continue to report Wyeth's president, chief operating officer (COO) and vice chairman, Bernard Poussot.