Shire P.L.C., which has grown from 100 local employees to about 1,100 since the specialty pharmaceutical company landed in Wayne in 2004, is nearing a decision on a likely move of its North American headquarters from Wayne to another spot in the region. Shire chief executive officer Angus Russell said during a recent wide-ranging interview that the company needed a campus-like setting to handle its current workforce and future growth. Although he said he had met with Mayor Nutter on a variety of topics, including the move, Russell would not identify possible relocation sites, in the city or elsewhere.