Dainippon Sumitomo Pharma (DSP) of Osaka, Japan, plans to acquire Norwood, Mass.-based Boston Biomedical (BBI).

DSP will make an upfront payment of $200 million to BBI shareholders, and will make development milestone payments of up to $540 million related to compounds BBI608 and BBI503 currently in development. It will also pay up to $1.9 billion in sales milestones.

DSP currently aims to commercialize BBI608 and BBI503 in 2015 or later. Both are small molecular oral drugs that aim to cause an antitumor effect in cancer stem cells. Although there are no successful anticancer drugs thus far, BBI and DSP believe BBI608 and BBI503 are likely to become the first anticancer drugs in the world targeting cancer stem cells. BBI608 is currently in the preparatory stage for phase III clinical trial for colorectal cancer inNorth Americaand in phase Ib and II clinical trials for various solid tumors. BBI503 is in phase I clinical trial for patients with various advanced solid tumors inNorth America.

DSP signed an exclusive license agreement with BBI in March 2011 for the rights to develop and commercialize BBI608 in Japanfor all indications of cancer. Seeing BBI's development pipeline led to DSP's decision to acquire BBI.

Acquisition of BBI is not only an acquisition of an innovative pipeline in the oncology area, it also represents obtaining an excellent drug discovery/development platform with the capabilities of BBI, enabling us to continuously create candidate compounds likely to advance into later development stages,” said Masayo Tada, president and CEO of DSP. “Subsequently we intend to establish our R&D base in the U.S. to expand our presence in cancer treatment globally. We are aiming to make the oncology area one of our future focus therapeutic areas next to the CNS area.

Once the acquisition closes in April, BBI will become a 100% owned subsidiary of DSP and continue its operation in the Boston area.