This blog post has been updated.

British drugmaker GlaxoSmithKline has expelled members of the executive suite, and most of the board of directors, at Rockville-based Human Genome Sciences on the same day it took control of the company, according to a regulatory filing.

Deirdre Connelly has been appointed president and chief executive at HGS, replacing H. Thomas Watkins. Adrian Rawcliffe will serve as chief financial officer and Daniel Troy as secretary. All three are existing Glaxo employees.

In a brief letter sent to HGS employees this morning, Watkins said the move was not unexpected, calling the changes “a necessary and well understood part of the acquisition process.”

“I and all of the other members of the HGS senior management team will remain part of HGS through at least the end of August,” Watkins said. “A number of our executive officers will remain involved in the integration process beyond that time, possibly through the end of the year.”

The removal of executives came after several members on HGS board of directors resigned and Glaxo replaced them with its own picks.

Argeris N. Karabelas, Augustine Lawlor and Gregory Norden retained their seats on the board. They are joined by Connelly, Rawcliffe and Troy, as well as Roger Connor, Chester Koczynski, David Redfern and Ian Tomlinson.

The shake-up was disclosed in a Securities and Exchange Commission filing that also announced the closure of the firm’s tender offer. Glaxo agreed to buy HGS earlier this month for $3.6 billion, or $14.25 a share, on an equity basis or approximately $3 billion net of cash and debt.

That deal came together after months of wrangling for control of the company. Glaxo had initially offered $2.6 billion for the firm, but HGS aggressively rebuffed the bid as too low.

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