Turnstone Biologics Acquires Novel Cell Therapy Platform

Acquisition of Myst Therapeutics adds proprietary tumor infiltrating lymphocyte (�TIL”) technology and programs to Turnstone’s growing portfolio

NEW YORK–(BUSINESS WIRE)–Turnstone Biologics Corp., a clinical-stage biotechnology company pioneering the development of cancer immunotherapies, today announced that it has acquired California-based Myst Therapeutics, a privately held biotechnology company focused on advancing novel T-cell therapies for solid tumors. The acquisition adds a pipeline of innovative TIL programs to Turnstone’s portfolio of oncolytic virus candidates. Financial terms were not disclosed.

TIL therapy treatment protocols utilize populations of T-cells that are isolated from a patient’s own tumor, expanded and stimulated before being re-administered to the patient. There has been strong clinical evidence demonstrating the benefit of TIL therapy in solid tumors such as melanoma and cervical cancer, however, driving clinical benefit in harder-to-treat cancers has been elusive. The Myst TIL therapy platform has been specifically designed to extend beyond the use of bulk TILs to enrich for the most relevant T-cells for tumor eradication, preserving broad antigen diversity and minimizing time to treatment for patients.

“Myst has created an industry-best selection strategy for identifying, expanding and stimulating antigen-reactive T-cells in a patient’s tumor,” said Mike Burgess, M.D., Ph.D., President of R&D at Turnstone. “It represents the most straight-line solution for broadening the benefit of TILs to other solid tumor indications while maintaining commercial feasibility. We are excited to advance this technology both independently and in combination with our viral immunotherapies.”

Myst has focused on applying their innovative T-cell selection strategies to clinically proven TIL treatment protocols. With this acquisition, Turnstone gains full access to this technology, the complete R&D capabilities of Myst along with existing development collaborations, and a pipeline of TIL programs with the lead candidate expected to enter the clinic this year.

“The Myst platform builds on validated and durable responses in the field and represents a next-generation approach to TILs that aligns directly with our commitment to exploiting the full potential of innate and adaptive tumor immunity,” said Sammy Farah, Ph.D., CEO at Turnstone. “It further strengthens our internal development expertise and expands our opportunity to deliver transformative medicines to the millions of cancer patients underserved by current treatment options.”

The acquisition of Myst will see an integration of talent across Turnstone’s senior management and R&D teams. Myst CEO, TJ Langer, will join Turnstone’s senior leadership team as Senior Vice President, Cell Therapy Development and External Innovation.

“The Turnstone team has extensive experience in the field of cancer immunotherapy, and I am delighted to join them to further develop this cutting-edge therapeutic modality,” said Mr. Langer. “We are confident that our TIL platform has the potential to offer a substantial improvement over current TIL therapies by driving meaningful and robust responses in a wide spectrum of tumors. It is extraordinary to have these leading oncolytic virus and cell therapy programs together under one roof.”

About Turnstone Biologics

Turnstone Biologics, a privately held clinical stage biotech company, is developing breakthrough cancer immunotherapies by advancing two leading and complementary platforms that drive innate and adaptive tumor immunity, to provide benefit to the millions of cancer patients underserved by current treatment options. Turnstone’s proprietary vaccinia virus platform is engineered to drive coordinated immune activation, potent viral activity, and local expression of encoded therapeutics. The innovative TIL cell therapy platform leverages clinically validated treatment protocols and has been specifically designed to extend beyond the use of bulk TILs to enrich for the most relevant T-cells for tumor eradication, preserving broad antigen diversity and minimizing time to treatment for patients. The Company has an ongoing Phase 1/2a trial in solid tumors (RAPTOR) for its leading oncolytic virus candidate, RIVAL-01, and is expecting to file an IND for the lead TIL therapy candidate, TIDAL-01, in 2021. For more information, please visit www.turnstonebio.com, and follow Turnstone on LinkedIn.

Contacts

Turnstone Biologics

Ahmed Aneizi

613-421-8930

ahmed.aneizi@turnstonebio.com