Williams, 44, was Immunex's top scientific officer when the company was bought by Thousand Oaks, Calif.-based Amgen. He cashed out about $6.3 million worth of Amgen stock last month, according to a filing with the Securities and Exchange Commission, and plans to move his family to New Zealand, where he will join a biotech company founded by a longtime friend.
The departure is the latest among the former Immunex executive ranks, following those of Chief Executive Ed Fritzky, Chief Operating Officer Peggy Phillips, the heads of the finance and legal departments and some key scientists. Fritzky has retained a seat on Amgen's board.
Publicly, Amgen has said Williams was important to making the merger a success, because he had 15 years of experience in science and management at Immunex, and the loyalty of the world-class scientists and developers who created Enbrel, the star rheumatoid-arthritis drug.
Williams' task following Amgen's $10 billion takeover was to hang onto Immunex's most talented people. In an interview last month, he dismissed rumors he was leaving, saying, "I'm signed on," and pointed proudly to Amgen's success in retaining 95 percent of Immunex employees to whom it had offered jobs.
Dr. Thomas Daniel, hired by Williams two years ago to bring a medical doctor's perspective to research, will take over as head of Seattle research when Williams steps down, effective Oct. 7.
Also helping to fill the void will be Roger Perlmutter, Amgen's executive vice president of research and development and a former head of the immunology department at the University of Washington. Perlmutter works at Amgen headquarters in California but keeps a home in the Seattle area and is expected to be actively involved here.
Williams explained his decision to employees in morning meetings in Seattle and Bothell. He said the elder of his two daughters is in eighth grade, giving his family a window of opportunity to move without being too disruptive to their schooling.
"I want to be able to take advantage of an opportunity and chart a new course and try a new adventure," Williams said. "I'm fortunate that I'm able to offer my family something that not many families are able to do."
Amgen spokeswoman Barbara Bronson Gray said the move was a surprise.
"He's a great guy, he's beloved by the staff and he's a true leader," Bronson Gray said. "It's a loss, I won't say otherwise, but the company will go on and do well."
Williams grew up in western Massachusetts and spent the bulk of his career at Immunex, but he has long-standing ties to the company he is joining, Genesis Research and Development of Auckland, New Zealand.
Through Immunex, he met Jim Watson, an internationally recognized immunologist who had an opportunity to be an Immunex co-founder. Watson went on to found Genesis in 1994. Immunex invested in it and struck up a research relationship, and Williams joined its board.
Williams was well-liked at Immunex for his strong scientific credentials, personable manner and a habit of deflecting credit to those who worked for him.
Bronson Gray and Williams both said the departure is not a sign of any diminishing commitment to Seattle. Bronson Gray reiterated Amgen plans to invest $600 million into the Helix Project for research and development along Elliott Bay, to finish construction by early 2004 and to house about 600 employees there. She added that Amgen is hiring 200 more people at a factory in Rhode Island that makes Enbrel.
Susan Erb, a longtime colleague at Immunex who didn't join Amgen, said the loss of Immunex's culture has been hard for many to take. She said Williams will be missed.
"It's a really difficult thing," Erb said. "It's really tough to get bought out when you always thought you were going to change the world and control your own destiny."
Luke Timmerman: 206-515-5644 or firstname.lastname@example.org.