Complex sentence: He then was hired by Caremark as its vice president for Disease Management Marketing and general manager of its Home Healthcare business unit; he spent four years advocating and directing the development of the company's first AIDS management program.
Split into simpler sentences: He then was hired by Caremark as its vice president for Disease Management Marketing and general manager of its Home Healthcare business unit. He spent four years advocating and directing the development of the company's first AIDS management program.