Abbott Laboratories (ABT) named a new head of its pharmaceutical unit, while the outgoing division chief takes over a new Abbott investment arm.

The Abbott Park, Ill., health-care products company said in a regulatory filing Monday it named Olivier Bohuon executive vice president of pharmaceutical products, effective Aug. 1. He was previously senior vice president of international pharmaceuticals.

Bohuon succeeds James Tyree, who will move to a new role as president of Abbott Biotech Ventures Inc., a new unit that will invest in early-stage pharmaceuticals and biologics.

Abbott spokeswoman Melissa Brotz said Tyree has experience identifying and securing pharmaceutical investments. In an earlier position with Abbott he served as vice president of global licensing and new business development. As for Bohuon, Brotz said Abbott's international pharmaceutical business has done extremely well under him.

Abbott's pharmaceutical unit is its biggest, contributing more than 55% of total company revenue. After a period of strong growth, the unit posted a sales decline for the first quarter, partly because of a slowdown in sales of its top product, Humira for rheumatoid arthritis and other conditions.

Tyree has had senior posts in the pharmaceutical unit since 2006. He was elected an Abbott corporate officer in 2001. Bohuon has held leadership posts in European and international operations since 2003, the year he was elected a corporate officer.

Abbott shares fell 66 cents to $45.34 Tuesday.

-Peter Loftus, Dow Jones Newswires; 215-656-8289; peter.loftus@dowjones.com