Traditional VCs appear to have missed the boat on Forma Therapeutics Holdings LLC because the platform company launched when many investors were focusing on late-stage companies or single-asset plays that could generate near-term returns. Early backing from strategic investors and a string of deals like this month's Celgene Corp. partnership have given Forma a free hand to build its drug discovery engine.

In the companies' second partnership in a year, Celgene paid Forma $225 million in cash up front for a 3.5-year research collaboration to discover and develop compounds targeting undisclosed protein families across a range of therapeutic areas.