COMING BACK: Dr. Roger Perlmutter, a former research executive at drugmaker Merck & Co., will return on April 15 to become director of Merck Research Laboratories.

TRANSITION GAME: Perlmutter, 60, will work for a time with current research head Peter Kim, 55. Kim is to leave Merck on Aug. 1 after a decade in the job.

PRODUCTIVE STRETCH: Perlmutter ran Amgen Inc.'s research from 2001 through February 2012. Over that stretch, he oversaw development of several pills and biologic drugs for conditions including cancer, endocrine and blood disorders, osteoporosis and inflammation.