In September 2009, Sepracor Inc was acquired by Japanese Pharmacuetical firm Dainippon Sumitomo Pharma. After the acquisition, Sepracor became a wholly owned subsidiary of Dainippon Sumitomo Pharma America Holdings, Inc., a wholly owned U.S. subsidiary of DSP, and continued operations based in Marlborough, Massachusetts and in Canada. In April 2010, DSP's original U.S. subsidiary, Dainippon Sumitomo Pharma America, Inc. (DSPA) was merged into Sepracor. Sunovion is the new company born of this union. Sunovion Pharmaceuticals Inc, is specialty pharmaceutical company developing improved versions of widely prescribed pharmaceutical compounds. The Improved Chemical Entities (ICE) development program identifies existing, widely prescribed drugs that might be replaced by improved single-isomer or active-metabolite forms of such drugs. Sepracor then seeks to develop ICEs that offer one or more benefits over the parent drugs, such as reduced side effects, improved therapeutic efficacy or effectiveness for new indications. The company has spun out several technology companies including publicly-traded BioSepra Inc. (NASDAQ: BSEP) and HemaSure, Inc. (NASDAQ: HMSR) and wholly-owned SepraChem Inc. and Versicor Inc.