$450 million deal takes existing collaboration one-step further.

Building on a previous partnership agreement between Japanese firm Astellas Pharma and US-based biotech startup Mitobridge, the two companies announced in late November that Astellas has elected to exercise its exclusive option right to acquire Mitobridge under the amended terms of the October 2013 partnership agreement. 

Mitobridge develops small-molecule therapeutics that enhance mitochondrial function. The previous partnership, which began in 2013, developed potential drug candidates targeting genetic, metabolic and neurodegenerative disorders and conditions of aging. The most advanced candidate is in Phase I clinical studies for Duchenne Muscular Dystrophy (DMD).

As part of the transaction, Astellas will pay Mitobridge a total of $450 million  $225 million upfront with up to $225 million in additional milestone payments related to the progress of programs in clinical development.

“Astellas has increased the involvement in mitochondrial drug discovery through its partnership with Mitobridge and the network of key scientists that the company has assembled. The achievements resulting from the collaboration have exceeded our expectations, including the rapid advancement of multiple programs,” said Yoshihiko Hatanaka, President and CEO of Astellas. “Through the acquisition of Mitobridge, Astellas accelerates our investment in diseases caused by mitochondria dysfunctions in order to deliver innovative new treatment options to patients.”

Added Kazumi Shiosaki, Ph.D., President, CEO and Co-founder of Mitobridge: “We at Mitobridge are delighted to become part of Astellas’ major initiative to develop new therapies for serious diseases. We are grateful for the tremendous support and guidance from Astellas, MPM Capital, and Longwood Fund that enabled Mitobridge to rapidly build an exciting pipeline. Mitobridge–as a subsidiary of Astellas–will now have additional resources to continue to advance and expand on its achievements to date.” The deal is expected to close in the next several weeks following regulatory approval.