NEW YORK (AP) -- Swiss drug developer Roche said Tuesday Ian Clark will replace Pascal Soriot as CEO of biotechnology unit Genentech in January.

Clark, 49, currently the head of global product strategy for pharmaceuticals, is moving into the new position as Soriot, 50, becomes chief operating officer of the pharmaceutical division. Current pharmaceutical division head, William M. Burns, 62, is retiring.

Arthur Levinson, Genentech's chairman and CEO, had been helping to lead the integration into Roche, which has previously said he would be nominated to join the board of directors in 2010.

The company's executive committee after Jan. 1 will include Roche CEO Severin Schwan, Chief Financial Officer Erich Hunziker, Soriot, and diagnostics division COO Daniel O'Day, among several others.

Roche completed its $46.8 billion takeover of Genentech in March and it expects the integration to be largely complete by the end of the year.