Sosei Subsidiary Heptares Enters Strategic Drug Discovery Collaboration with Pfizer Inc. Focused on GPCR Targets Across Multiple Therapeutic Areas

TOKYO--()--Sosei Group Corporation ("Sosei") (TOKYO:4565) today announces that its wholly-owned subsidiary, Heptares Therapeutics has entered into a strategic drug discovery collaboration with Pfizer Inc. (NYSE: PFE) to research and develop potential new medicines directed at up to 10 G protein-coupled receptor (GPCR) targets across multiple therapeutic areas.

Heptares will use its proprietary GPCR structure-guided platform to help deliver stabilised GPCRs (StaR® proteins), high-resolution crystal structures and other technologies to support the discovery of potential novel agents directed to the GPCR targets selected by Pfizer. Pfizer will be responsible for developing and commercialising any potential therapeutic agents (small molecules or biologics derived from StaR antigens) for each target and will have exclusive global rights to any potential resulting agents.

Heptares will receive an initial payment on signing the agreement in return for delivering certain StaR proteins and structures for targets selected by Pfizer that it has already generated.

Heptares is eligible to receive potential research, development, regulatory and commercial milestone payments of up to USD189 million per target. In addition, Heptares is eligible to receive potential tiered royalties on the net sales of any products that are commercialised by Pfizer.

In addition, Sosei and Pfizer Seiyaku KK ("Pfizer KK") have entered into an equity agreement under which Pfizer KK will purchase USD33 million of newly issued Sosei common stock at a premium of 25% to the average closing price during the 20-day period prior to the closing date. The closing is expected to be in December 2015. The investment will represent approximately 3.02% of the enlarged Sosei share capital and is subject to review by Japanese financial authorities.

"This extensive partnership with Pfizer is an important step toward realizing full potential of Heptares' technology. Alliances of this kind also play an important role in achieving Sosei's ambition for becoming a leading global biopharmaceutical company of Japanese origin," commented Shinichi Tamura, CEO of Sosei Group.

Commenting on the agreement, Malcolm Weir, Chief Executive Officer of Heptares and Chief R&D Officer of Sosei Group, said: "This strategic collaboration with Pfizer, spanning as it does many targets and indications, is another significant achievement for Heptares and recognises the potential clinical benefit that may be realisable through the combination of our continuing leadership in GPCR structure-based design technology and Pfizer's global therapeutic drug discovery and development capabilities. We are delighted to be embarking on this new collaboration and look forward to an exciting and productive relationship."

"Pfizer looks forward to this collaboration with Heptares to help us more quickly screen and identify lead GPCR programs across multiple therapeutic areas within our preclinical portfolio and, ultimately, help us increase the speed at which we bring potential new therapies to patients," said Rod MacKenzie, senior vice president, PharmaTherapeutics Research & Development at Pfizer.

Notes to Editors:

About Sosei

Sosei is a biopharmaceutical company originating from Japan but with global presence. Sosei's primary business model is based on identifying novel and/or differentiated product assets or technology platforms and, through supporting these in preclinical and clinical development and establishing commercial partnerships, advancing new medicines to patients worldwide.
For more information about Sosei, please visit www.sosei.com/en.

About Heptares Therapeutics

Heptares is a clinical-stage company creating transformative medicines targeting G protein-coupled receptors (GPCRs), a superfamily of 375 receptors linked to a wide range of human diseases. Heptares proprietary structure-based drug design technology enables us to engineer drugs for highly validated, yet historically undruggable or challenging, GPCRs. Using this approach, we have built an exciting pipeline of new medicines with the potential to transform the treatment of Alzheimer's disease, schizophrenia, migraine, addiction, metabolic disease, and other indications. Our pharmaceutical partners include Pfizer, AstraZeneca, MedImmune, MorphoSys and Teva. Heptares is a wholly owned subsidiary of Sosei Group Corporation. For more information, please visit www.heptares.com and www.sosei.com/en.