Vertex CEO Matthew Emmens is stepping down from that post after the company’s best year ever and amid skyrocketing sales of its hepatitis C drug Incivek. Emmens will stay on as executive chairman through May and will continue to sit on the board of directors thereafter. Replacing him as CEO is Dr. Jeffrey Leiden, a Vertex board member, venture capitalist, practicing cardiologist and molecular biologist.

Kevin Sharer will retire as Amgen’s CEO in May, to be replaced by Robert Bradway, the firm’s current president and chief operating officer . Bradway will also take over the chairman role once Sharer leaves that position at the end of 2012. In addition, EVP for R&D Dr. Roger M. Perlmutter will retire effective Feb. 12 and will be succeeded by Dr. Sean Harper, the company’s chief medical officer.