Sumitomo merges U.S. biotechs to create oncology division

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SDP Oncology will advance a pipeline led by napabucasin and alvocidib. (Grantuking/CC BY 2.0)(By Grantuking from Cerrione, Italy (Tokyo Uploaded by Smooth_O) [CC BY 2.0 (], via Wikimedia Commons)

Sumitomo Dainippon Pharma has merged Tolero Pharmaceuticals and Boston Biomedical to form an oncology division with sites in Massachusetts and Utah. The U.S. unit, Sumitomo Dainippon Pharma Oncology Inc., will work with Sumitomo sites in Japan to advance a pipeline of cancer prospects.

Japan’s Sumitomo bought Boston Biomedical for $200 million upfront to get its hands on a pair of cancer stemness inhibitors, BBI503 and BBI608. Boston Biomedical terminated two trials of BBI503 last year, but BBI608, also known as napabucasin, remains in development. At Sumitomo Dainippon Pharma Oncology, napabucasin heads up a pipeline that also features contributions from Tolero.

Sumitomo struck a deal to buy Tolero in 2016, again by offering $200 million upfront and more on the back end. The takeover gave Sumitomo control of CDK9 inhibitor alvocidib, which is now being tested in midphase blood cancer clinical trials.

Boston Biomedical and Tolero operated as wholly owned subsidiaries of Sumitomo in the years after the acquisitions, keeping their own names and sponsoring their own trials. Sumitomo has decided to end that arrangement by merging the two biotechs to make Sumitomo Dainippon Pharma Oncology Inc. The U.S. unit will work with Japanese R&D sites under the name SDP Oncology. 

Patricia Andrews, former CEO of Boston Biomedical, will lead the combined entity. David Bearss, founder and CEO of Tolero, has taken up the chief scientific officer post at SDP Oncology. Boston Biomedical’s Edgar Braendle and Masashi Murata make up the rest of the global leadership team. 

Andrews and her colleagues will advance a pipeline led by napabucasin and alvocidib. SDP Oncology has another midstage prospect, WT1 cancer vaccine DSP-7888, and seven candidates in early-phase clinical development.

Sumitomo is looking to the pipeline to help offset the anticipated impact of the arrival of generic competitors to bipolar depression drug Latuda, although prior setbacks have raised doubts about the prospects of some of the assets. Notably, napabucasin has failed phase 3 colorectal and pancreatic cancer trials in recent years.