 He held several research, clinical and regulatory positions at Lilly in the United States and England before joining the biotechnology company, Sphinx Pharmaceuticals, Inc. in Durham, North Carolina in 1990 as executive vice president and chief operating officer.In 1992, he joined Progenitor, Inc. as president and chief executive officer.Then, in 1993, he joined Interneuron Pharmaceuticals in Lexington, Massachusetts, Progenitor’s parent company, as chairman and chief executive officer.