Turnstone announces ongoing enrollment of Marabex clinical trial

Marabex™ trial to assess the safety of a novel tumour-targeted oncolytic virus vaccine in patients with advanced solid tumours

Turnstone Biologics Inc. ("Turnstone" or the "Company"), a FACIT portfolio company, has announced the ongoing enrollment of the Marabex™ clinical trial assessing the safety and immune responses in patients with advanced or metastatic, MAGE-A3-expressing solid tumours.

Harnessing the patient's immune system is a promising new avenue in the fight against cancer that continues to garner significant momentum and excitement. Turnstone's technology platform, Marabex™, is a novel approach that combines the benefits of oncolytic viral therapy with a tumour-targeted vaccine into a single intravenously-delivered treatment to improve potency and enhance patient outcomes. Preclinical studies using this new strategy have demonstrated unprecedented immune responses against tumours and builds on recent clinical validation of oncolytic viruses, positioning the Marabex™ technology to expand the boundaries for new treatments and benefit a large group of patients.

This initial landmark trial is a world's first to combine two viruses, one given intravenously, into a single anti-cancer vaccine therapy. The clinical trial is managed by the NCIC Clinical Trials Group with financial support from the Ontario Regional BioTherapeutics Program (ORBiT) at the Ontario Institute for Cancer Research (OICR). As Turnstone was created to accelerate and steward the broader clinical development of the Marabex™ technology platform, this trial also forms the basis of multiple upcoming clinical studies exploring the potential of the Marabex™ oncolytic vaccine in combination with other emerging immune therapies and standard cancer therapies.

A media event announcing the clinical trial was held this morning at The Ottawa Hospital, with Turnstone's academic and clinical partners as well as the Company's founding scientists in attendance. The Marabex™ platform integrates breakthrough discoveries supported by OICR, FACIT, Children's Hospital of Eastern Ontario (CHEO) Research Institute, McMaster University, The Ottawa Hospital, and the University of Ottawa. This clinical trial highlights the opportunities associated with multi-institutional collaborations and OICR's innovative translational research platforms.

"We congratulate our colleagues in the ORBiT program at CHEO, McMaster and The Ottawa Hospital for initiating this important clinical trial. We look forward to building upon these important scientific findings to advance this and other promising technologies from the Marabex™ platform, and achieving our mission to improve the lives of patients with cancer," remarked Jeff Courtney, Turnstone's Chief Executive Officer and Chief Commercial Officer of FACIT.