Like in many industries, knowledge management is the key to the successful developments of new drugs and other commercialized products in the pharmaceutical sector. Prior studies have shown that knowledge management requires effective external knowledge sourcing strategies. We argue that both the geographic distance to external knowledge sources and the diversity of such sources have strong influences on the success of the search process and the development of new drugs. We test these theoretical assumptions by applying several advanced estimation techniques on a combined broad set of data from the U.S. Patent and Trademarks Office (USPTO) and U.S. Food and Drug Administration (FDA). We find empirical evidence that the intensity of external knowledge sourcing activities has a positive effect on new drugs approval and commercialization. Specifically, our models predict that a higher number of references to prior patents increases the probability of a new patented drug to be approved and commercialized. Furthermore, the geographic distance covered in the search for external knowledge also positively contributes to drug commercialization. Important management implications derived from these findings are also discussed in the paper.