Pacific Horizon is an active venture investor, often owning large majority stakes in its portfolio companies. The venture capitalist has taken two different strategies with its majority-owned virology investments, Illumigen and Koronis, eschewing and embracing risk, respectively. Each firm, however, represents a potential game-changing opportunity, and illustrates PHV's back-to-basics venture philosophy: making novel-mechanism bets that are perceived as having both high scientific risks and long-term potential paybacks