• GPR35 is a novel target with an established genetic association to IBD
  • UK regulatory approval received to commence first-in-human studies
  • Independent commercial analysis supports a worldwide peak sales opportunity of more than US$3 billion for GSK4381406 with its unique target product profile

TOKYO, Japan and CAMBRIDGE, UK I November 24, 2023 I Sosei Group Corporation (“Sosei Heptares” or “the Company”; TSE: 4565) announces it has initiated discussions with GSK to regain full ownership of GSK4381406, a highly selective first-in-class, oral GPR35 agonist in development under a Global Collaboration and License Agreement with GSK as a potential new treatment for Inflammatory Bowel Diseases (IBD). GPR35 is an important orphan G protein-coupled receptor (“GPCR”) with an established genetic association to IBD, for which there remains significant unmet need for millions of sufferers worldwide.

GSK4381406 was designed by Sosei Heptares using its proprietary structure-based drug design (SBDD) platform and licensed to GSK in 2020. Since then, Sosei Heptares and GSK have advanced GSK4381406 through a joint development program, generating promising mechanistic, preclinical and safety data suggesting that it may have the potential to improve barrier function and reduce visceral pain in gastrointestinal indications such as ulcerative colitis and irritable bowel syndrome.

These data enabled Sosei Heptares and GSK to gain approval from the UK Medicines and Healthcare products Regulatory Agency (“MHRA”) in mid-2023 to enter GSK4381406 into first-in- human studies (NCT05999708).

The Company is to regain full ownership of the GSK4381406 program following a decision by GSK to deprioritize and discontinue its development due to changes to both its immunology research strategy and immunology research leadership. The decision was not based on any scientific, preclinical or safety data related to GSK4381406. Under the terms of the 2020 agreement between the companies, Sosei Heptares has the right – for no upfront payment – to regain full ownership of the GSK4381406 program, together with all associated intellectual property licensed by Sosei Heptares to GSK, and preclinical data generated under the partnership. GSK becomes eligible for a low single digit royalty from Sosei Heptares on net sales of GSK4381406 should it become commercially available.

Sosei Heptares’ strategy is to advance novel or best-in-class products through early clinical development before seeking a partner to develop and commercialize in major markets. Following the Company’s acquisition of Idorsia’s pharmaceutical businesses in Japan and Korea, Sosei Heptares also now has full clinical development and commercialization capabilities in the Japan/Asia-Pacific regions (ex-China).

Upon completion of the process to regain ownership of the GSK4381406 program, Sosei Heptares expects to proceed with the planned Phase 1 trial in the UK itself while determining the optimal strategy for the further clinical development and/or re-partnering of the program. The event reported today has no immediate impact on the consolidated financial results for the accounting period ending December 2023. Should any impacts or other matters that require an announcement be identified, the Company will announce such matters promptly.

Chris Cargill, President & CEO of Sosei Heptares, commented: “We are delighted at the prospect of regaining ownership of GSK4381406 from GSK. This exciting program has already delivered highly promising preclinical data that support its potential as a new therapy for IBD and is poised to enter a Phase 1 clinical trial.

“We have enjoyed a productive partnership with GSK over the past few years and understand and respect its decision as the result of a reprioritization of its immunology pipeline. For Sosei Heptares, this represents a significant opportunity, and one we have capitalized on several times over recent years, to regain and re-partner promising programs that have benefited from external collaboration and investment to validate their potential and advance them through development.  

“The return of the GPR35 agonist program, with its first-in-class mechanism of action and potential to address major unmet needs in IBD worldwide, would be a welcome addition to our growing clinical pipeline. We have already commissioned an independent commercial analysis and believe GSK4381406 has global peak sales potential of more than US$3 billion given its unique target product profile. This presents a strong rationale and clear opportunity for Sosei Heptares to further advance this program, either alone by leveraging our expanded development and commercialization capabilities, and/or in partnership.”

About the Agreement with GSK
Sosei Heptares and GSK entered into a Global Collaboration and License Agreement in December 2020, under which GSK licensed global rights to a portfolio of GPR35 agonists, including GSK4381406, that were designed by Sosei Heptares using its StaR® technology and structure-based drug design (SBDD) platform. Sosei Heptares and GSK jointly conducted the research and early preclinical development phase, and GSK was to lead clinical development, manufacturing and commercialization. Further details of the agreement can be found by clicking here.

* Compound code to be changed to Sosei Heptares’ format in future.

About Sosei Heptares

Sosei Heptares is a fully integrated biopharmaceutical company focused on bringing life-changing medicines based on world-class science to patients globally. Our vision is to become one of Japan’s global biopharmaceutical champions.

Our global business combines our world-leading GPCR-targeted StaR® technology, structure-based drug design and early development capabilities in the UK with a highly experienced clinical development capability and a commercial operation in Japan.

We are leveraging these capabilities to generate and advance a broad and deep pipeline of novel medicines across multiple therapeutic areas, including neurology, immunology, gastroenterology and inflammatory diseases. We intend to develop these opportunities for patients in Japan and globally both internally and through our partnerships with global biopharmaceutical companies and emerging technology companies.

Sosei Heptares operates from key locations in Tokyo and Osaka (Japan), London and Cambridge (UK), Basel (Switzerland) and Seoul (South Korea).

For more information, please visit https://soseiheptares.com/
LinkedIn: @soseiheptaresco | Twitter: @soseiheptaresco | YouTube: @soseiheptaresco

SOURCE: Sosei Heptares