Daiichi will be paying $805m up-front with near-term milestone payments associated with the approval of Plexxikon’s melanoma treatment drug PLX4032 adding up to another $130m.
The acquisition will be internally funded, and Daiichi Sankyo will retain the US co-promotion rights for PLX4032 after the acquisition.
PLX4032 is Plexxikon’s lead program which the company has co-developed with Swiss pharma major Roche.
It is an oral, novel drug which targets the oncogenic BRAF mutation present in almost half of melanoma cancers and about eight percent of all solid tumors.
Patients treated with PLX4032 have demonstrated improved overall survival (OS) and improved progression-free survival (PFS) compared to patients treated with dacarbazine, the current standard of care.
Daiichi Sankyo CEO Joji Nakayama said Plexxikon’s acquisition will help accelerate the growth of Sankyo’s franchise, especially by co-promoting PLX4032 as a very exciting personalized medicine.
Plexxikon CEO Peter Hirth said together with Daiichi Sankyo, the company hopes to leverage its accelerated discovery and development capabilities in a unique but supportive structure.
PLX3397 is another oral, selective kinase inhibitor in Plexxikon’s pipeline of products.
It is in the late stages of a Phase 1 dose escalation trial, and there are plans to initiate several Phase 2 trials with PLX3397 in specific cancers in 2011, including Hodgkin lymphoma, AML, glioblastoma and metastatic breast cancer.
Plexxikon has also initiated a Phase 1 study for PLX5622, an oral agent indicated for the treatment of rheumatoid arthritis.