The document summarizes key findings from EvaluatePharma's 2014 Orphan Drug Report. It finds that worldwide orphan drug sales are forecast to reach $176 billion by 2020, almost double the growth of the overall prescription drug market. Orphan drugs are expected to account for 19.1% of worldwide prescription sales by 2020. The report also notes that Soliris, used to treat rare blood disorders, generates the highest revenue per patient of any orphan drug in the US.