Lexicon Genetics Inc., of The Woodlands, Texas, appointed C. Thomas Caskey chairman of its board of directors and elected to the board Sam Barker, formerly with Bristol-Myers Squibb Co.

Neose Technologies Inc., of Horsham, Pa., named P. Sherrill Neff chief operating officer in addition to his current position as president.

Neurocrine Biosciences Inc., of San Diego promoted Paul Hawran to executive vice president.

Nexell Therapeutics Inc., of Irvine, Calif., appointed Lewis Chapman vice president, global marketing; Wayne Tyo, corporate controller; and Dennis Van Epps vice president, research and development.

Sangamo BioSciences Inc., of Point Richmond, Calif., appointed Alan Wolffe senior vice president and chief scientific officer, and Julianna Wood senior director of corporate communications.