PureTech Presents New Data Reinforcing Galectin-9 as a Compelling Therapeutic Target and Biomarker for a Range of Cancers at the American Association for Cancer Research Annual Meeting

Data include largest cohort of breast cancer samples ever evaluated in this context and demonstrate that high levels of galectin-9 are associated with shorter time to disease relapse

Wholly-owned novel monoclonal antibody (LYT-200) is designed to selectively inhibit galectin-9, with a first-in-human clinical trial expected to begin in 2H 2020

PureTech presented new data at the American Association for Cancer Research (AACR) 2020 Virtual Annual Meeting providing compelling evidence that therapies targeting galectin-9 may impede tumor growth through immune rescue in an array of solid tumors. The research also establishes galectin-9 as an important biomarker for patient stratification. These data support PureTech’s wholly-owned immuno-oncology product candidate LYT-200, a first-in-class, fully human monoclonal antibody targeting galectin-9. (Graphic: Business Wire)

BOSTON--()--PureTech Health plc (LSE: PRTC) (“PureTech” or the “Company”), a clinical-stage biotherapeutics company dedicated to discovering, developing and commercializing highly differentiated medicines for devastating diseases, today shared new data establishing galectin-9 as a novel target for cancer immunotherapy and providing compelling evidence that therapies targeting galectin-9 may enable the immune system to attack an array of solid tumors. The data were shared in a scientific poster presented at the June session of the American Association for Cancer Research (AACR) 2020 Virtual Annual Meeting.

PureTech is developing a first-in-class, fully human monoclonal antibody targeting galectin-9. The product candidate, LYT-200, is expected to enter a first-in-human, Phase 1a/1b study in 2020 in hard-to-treat cancers, including pancreatic, cholangiocarcinoma and certain types of colorectal and liver cancers, which remain insufficiently responsive or resistant to currently approved checkpoint inhibitors. PureTech has previously presented data demonstrating LYT-200’s efficacy in reducing tumor growth and reactivating human effector T cells in preclinical, patient-derived tumor culture models.

“These new data clearly establish the importance of galectin-9 as a therapeutic target, given that its high expression across tumor types correlates with poor patient outcomes. Our analysis of more than 1,000 samples from human breast cancer tumors found that high levels of galectin-9 are associated with shorter time to disease relapse as well as with a tumor microenvironment that lacks cytotoxic CD8+ T cells that would otherwise be able to attack the tumor,” said Joseph Bolen, PhD, chief scientific officer at PureTech. “Our first-in-class monoclonal antibody, LYT-200, is designed to target and inhibit galectin-9 and thereby reverse this suppression of the immune system to boost its ability to destroy tumors. We’re proud to be presenting this research at AACR and look forward to advancing LYT-200 into the clinic later this year, as well as to progressing our work on galectin-9 as a biomarker.”

The AACR poster details a study undertaken by PureTech and its academic collaborators to evaluate the importance of galectin-9 expression in the tissues of cancer patients. The study is believed to include the largest cohort of breast cancer patient samples ever evaluated in this context, as well as robust cohorts of pancreatic and cholangiocarcinoma cases, and it found high expression of galectin-9 across all of these tumor types. Importantly, the highest levels of galectin-9 correlated with shorter time to disease relapse and poor survival. Strong galectin-9 expression was observed on the membranes of tumors with poor prognosis, which indicates this target is attractive for an antibody therapeutic such as LYT-200. In breast cancer, galectin-9 expression was associated with tumors showing worse pathological features, such as high tumor grade and estrogen receptor negativity, as well as features characteristic of an immunosuppressed tumor microenvironment, including the absence of CD8+ T cells. Collectively, these data suggest that galectin-9 could be significant both as a therapeutic target for a range of cancers and as a cancer biomarker, which PureTech intends to explore further for patient stratification.

About PureTech Health

PureTech is a clinical-stage biotherapeutics company dedicated to discovering, developing and commercializing highly differentiated medicines for devastating diseases, including intractable cancers, lymphatic and gastrointestinal diseases, central nervous system disorders and inflammatory and immunological diseases, among others. The Company has created a broad and deep pipeline through the expertise of its experienced research and development team and its extensive network of scientists, clinicians and industry leaders. This pipeline, which is being advanced both internally and through PureTech’s Founded Entities, is comprised of 24 products and product candidates, including two that have been cleared by the US Food and Drug Administration (FDA). All of the underlying programs and platforms that resulted in this pipeline of product candidates were initially identified or discovered and then advanced by the PureTech team through key validation points based on the Company’s unique insights into the biology of the brain, immune and gut, or BIG, systems and the interface between those systems, referred to as the BIG Axis.

For more information, visit www.puretechhealth.com or connect with us on Twitter @puretechh.

Forward Looking Statement

This press release contains statements that are or may be forward-looking statements, including statements that relate to the company's future prospects, developments, and strategies. The forward looking statements are based on current expectations and are subject to known and unknown risks and uncertainties that could cause actual results, performance and achievements to differ materially from current expectations, including, but not limited to, those risks and uncertainties described in the risk factors included in the regulatory filings for PureTech Health plc. These forward-looking statements are based on assumptions regarding the present and future business strategies of the company and the environment in which it will operate in the future. Each forward-looking statement speaks only as at the date of this press release. Except as required by law and regulatory requirements, neither the company nor any other party intends to update or revise these forward-looking statements, whether as a result of new information, future events or otherwise.

Contacts

Investors
Allison Mead Talbot
+1 617 651 3156
amt@puretechhealth.com

EU media
Ben Atwell, Rob Winder
+44 (0) 20 3727 1000
ben.atwell@FTIconsulting.com

US media
Stephanie Simon
+1 617 581 9333
stephanie@tenbridgecommunications.com

Release Summary

PureTech Presents New Data Reinforcing Galectin-9 as a Compelling Therapeutic Target and Biomarker for a Range of Cancers at the AACR Annual Meeting

Contacts

Investors
Allison Mead Talbot
+1 617 651 3156
amt@puretechhealth.com

EU media
Ben Atwell, Rob Winder
+44 (0) 20 3727 1000
ben.atwell@FTIconsulting.com

US media
Stephanie Simon
+1 617 581 9333
stephanie@tenbridgecommunications.com