The Business Journal's annual listing of the largest local players in the pharmaceutical industry shows a sector that remains in decline—a year-over-year drop of 4.5% to 2,521 employees—with several firms with significant operations here either shrinking their local base of operations or closing altogether. Of the seven companies ranked in the Business Journal annual survey, six are headquartered in Orange County. Irvine is the city favored by four. The Irvine-based aesthetics operations of AbbVie Inc. easily retained its top spot as the largest of all drugmakers doing business in the county, despite ongoing retrenchment in the area. AbbVie employs an estimated 1,300 in Orange County out of 50,000 companywide. AbbVie, the maker of the blockbuster arthritis and Crohn's disease medicine Humira, bought Botox maker Allergan for $63 billion in 2019.