Electronic Health Records for Drug Repurposing: Current Status, Challenges, and Future Directions.

It is well recognized that the global pharmaceutical industry now faces challenges such as high costs and low productivity when developing new drugs (e.g., it is estimated that the average cost for developing a new drug ranges from US $2 billion to $3 billion with the total time to bring it to the market being about 13–15 years). Therefore, drug repurposing (also called drug repositioning/reprofiling), which finds new indications for existing drugs, has received great attention in the past decade. Drug repurposing can reduce drug development time, while improving success rates because the toxicity profiles of existing drugs are already known. Studies have shown that new applications for repurposed drugs have nearly a 30% success rate for US Food and Drug Administration (FDA) approval, whereas traditional new drug applications have < 10% approval rate.