Sosei Group Company

HTL0039732 is a novel EP4 antagonist with the potential to treat a wide range of cancers in combination with other immunotherapies

TOKYO, Japan and LONDON and CAMBRIDGE, UK, July 22 Feb. 2022 (GLOBE NEWSWIRE) — Sosei Group Corporation (“the Company”; TSE: 4565), an international biopharmaceutical company and world leader in GPCR1-structure-based drug design and development (SBDD) and Cancer Research UK, the world’s largest private funder of cancer research, today announce the signing of an agreement to make cancer immunotherapy drug candidate from Sosei Heptares a first-in-human trial.

Under the Clinical Trial and Licensing Agreement (CTLA), the Cancer Research UK Drug Development Center will sponsor, design and execute a Phase I/IIa clinical trial of HTL00397322a new selective EP4 antagonist.

Sosei Heptares will be responsible for CTA’s enabling activities including GLP toxicology, IMP manufacturing1 and other preclinical studies necessary for the initiation of the clinical trial. Sosei Heptares is licensing the results generated in the trial to further clinical development and commercialization of HTL0039732.

HTL0039732 has been proposed for a range of cancers, including stable microsatellites3 colorectal, gastroesophageal, head and neck cancer and castration-resistant prostate cancer.

Many people with these types of cancer have missed out on the benefits of common immunotherapies, such as PD1/L1 checkpoint inhibitors4, have brought to other types of cancer. The hope is that this trial may reveal that HTL0039732 is an effective immunotherapy for these underserved patient populations.

HTL0039732 is a type of immunotherapy known as an EP4 antagonist, which means it binds and selectively blocks a specific type of prostaglandin receptor5 called EP4. Prostaglandin E2 (PGE2)-mediated signaling via EP4 can induce cancer cells to evade the immune system and can also influence tumor cell growth. Therefore, blocking this type of receptor may improve patient survival, especially if used in combination with another immunotherapy.

Director of the Center for Drug Development at Cancer Research UK, Dr Nigel Blackburn, said: “People with these types of cancer have, to date, largely missed some of the remarkable advances in the field of immunotherapy.

“We are therefore delighted to partner with Sosei Heptares to bring their novel immunotherapy candidate into human trials. The hope is that with more trials like this, all cancer patients will eventually be able to benefit from this potentially life-saving form of cancer treatment. .”

Matt Barnes, Chairman of Heptares Therapeutics and Head of UK R&D, commented“We are extremely pleased to collaborate with Cancer Research UK to advance HTL0039732 into Phase I/IIa clinical trials and take a step forward in bringing new treatments to cancer patients.

“HTL0039732 was rationally designed using our highly productive SBDD platform specifically for this type of immunotherapy approach and as such we believe it has the potential to be an EP4 antagonist of first order.”

Notes to Editors

Further details of HTL0039732 will be presented at the Gordon Research Conference in Medicinal Chemistry 2022 in early August 2022.

1GPCRs (G protein-coupled receptors) are a superfamily of integral cell membrane proteins that are present on cells and tissues throughout the body. GPCRs are involved in signaling pathways that influence a wide range of biological processes and are important drug targets implicated in many human diseases and disorders. CTA – Clinical Trial Authorization; GLP – Good Laboratory Practices; IMP – Investigational Drug

2HTL0039732 will be evaluated as both combination therapy and monotherapy

3About 80-85% of colorectal cancer patients are classified as “stable microsatellites”, which means they have low instability of short, repeated sequences of DNA in their tumors, called microsatellites. MSS tumors often exist in an environment that suppresses the immune system and does not respond well to immunotherapies.

4Checkpoint inhibitors block proteins, called checkpoint proteins, that prevent the immune system from attacking cancer cells. Examples of checkpoint inhibitors include pembrolizumab (Keytruda), ipilimumab (Yervoy), nivolumab (Opdivo), and atezolizumab (Tecentriq).

5Prostaglandins are a group of lipids made at sites of tissue damage or infection that are involved in the treatment of injury and disease. They control processes such as inflammation, blood flow, blood clot formation, and induction of labor.

About the Cancer Research UK Drug Development Center
Cancer Research UK has an impressive track record in developing new cancer treatments. The Cancer Research UK Center for Drug Development has been a pioneer in the development of new cancer treatments for 25 years, taking more than 140 potential new cancer agents into clinical trials in patients. It currently has a portfolio of 21 new anticancer agents in preclinical development, in phase I or at the start of phase IIa clinical trials. Six of these new agents have been brought to market, including temozolomide for brain cancer, abiraterone for prostate cancer and rucaparib for ovarian cancer. Two other drugs are nearing the end of phase III development trials.

About Cancer Research UK

  • Cancer Research UK is the world’s leading cancer charity dedicated to saving lives through research.

  • Cancer Research UK’s pioneering work in preventing, diagnosing and treating cancer has saved millions of lives.

  • Cancer Research UK receives no funding from the UK government for its lifesaving research. Every step he takes to beat cancer relies on vital donations from the public.

  • Cancer Research UK has been at the heart of progress that has already doubled survival in the UK over the past 40 years.

  • Today, 2 out of 4 people survive their cancer for at least 10 years. Cancer Research UK’s ambition is to accelerate progress so that by 2034, 3 out of 4 people will survive their cancer for at least 10 years.

  • Cancer Research UK supports research into all aspects of cancer through the work of over 4,000 scientists, doctors and nurses.

  • Together with its partners and supporters, Cancer Research UK’s vision is to bring forward the day when all cancers are cured.

For more information on the work of Cancer Research UK or to find out how to support the charity, please call +44 (0)300 123 1022 or visit follow us on Twitter and Facebook.

About Sosei Heptares

We are an international biopharmaceutical group focused on the discovery and early development of new drugs based on our patented GPCR-targeted StaR® technology and structure-based drug design platform capabilities. We are developing a broad and deep pipeline of new drugs in multiple therapeutic areas, including neurology, immunology, gastroenterology and inflammatory diseases.

We have established partnerships with some of the world’s largest pharmaceutical companies and many emerging technology companies, including AbbVie, AstraZeneca, Biohaven, Genentech (Roche), GSK, Neurocrine Biosciences, Novartis, Pfizer, Takeda and Verily. Sosei Heptares is headquartered in Tokyo, Japan, with corporate and R&D facilities in Cambridge, UK.

“Sosei Heptares” is the trademark and trademark of Sosei Group Corporation, which is listed on the Tokyo Stock Exchange (ticker: 4565). Sosei, Heptares, the logo and StaR® are registered trademarks of Sosei Group companies.

For more information, please visit
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Cancer research in the UK
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