Samuel D. Isaly founded the investment business of OrbiMed in 1989 with a vision to invest across the spectrum of healthcare companies: from private start-ups to large multinational companies. The investment team and capabilities of the firm have expanded considerably over time. Beginning with a mutual fund in 1989, investment activities were broadened to include long/short equity and venture capital investments in 1993.

As a result of OrbiMed's growing capabilities in private equity, the firm launched a dedicated venture capital fund, Caduceus Private Investments, in 2000. Caduceus Private Investments II followed in 2003 and Caduceus Private Investments III was launched in 2006 with committed capital of over $500 million.

Today, OrbiMed has a singular focus on seeking successful investments on a worldwide basis across the entire spectrum of private and publicly-traded life sciences companies. Assets under management currently exceed $6 billion, ranking OrbiMed as the world's largest healthcare-dedicated investment firm.