After gaining an option in 2011 to license Japanese rights to Boston Biomedical’s BBI608, an orally administered cancer stem cell (CSC) inhibitor, Japan’s Dainippon Sumitomo Pharma (DSP) has agreed to acquire the US biotech for as much as US$2.63 B, US$200 M of which will come upfront. As well as two clinical-stage programmes and a CSC drug discovery platform, the acquisition will provide DSP with an R&D base in the US.