Geneos Therapeutics, a clinical-stage biotherapeutics company developing personalized immunotherapies for cancer (PICs), today announced that two patients with aggressive cancers – one with glioblastoma multiforme (GBM), and another with advanced hepatocellular carcinoma (HCC) treated in the second line – remain on personalized immunotherapy for cancer (PIC) monotherapy, recurrence free and healthy, after more than six years and five years of ongoing treatment, respectively. Both achieved complete responses and neither has experienced any PIC-related adverse event greater than Grade 1 nor any PIC-related serious adverse event. Additional clinical trial patients with GBM and advanced HCC receiving PIC monotherapy continue to progress toward five years of recurrence-free survival.

“Geneos’ PICs as monotherapy have now enabled patients with two distinct, difficult-to-treat, rapidly progressing cancers to live beyond five years, recurrence free and healthy – living rich, fulfilling lives," said Niranjan Sardesai, Ph.D., President and Chief Executive Officer of Geneos. "These cases, together with our broader clinical trial results, highlight the durability and tolerability we believe to be achievable with our DNA-based PIC therapy. These results are encouraging and we look forward to continuing to advance our clinical program so that we may bring this potential new treatment option to people living with aggressive cancers rapidly.”

The U. S. Food and Drug Administration (FDA) recently released draft guidance identifying overall survival (OS) as a key endpoint in oncology trials. Geneos believes the long-term survival being seen in PIC-treated patients aligns with these regulatory expectations and strengthens the case for broader clinical development.

“Durable overall survival of five years or more in GBM and advanced HCC are uncommon, while recurrence-free survival is almost unheard of," said Ildiko Csiki, M.D., Ph.D., Geneos Chief Medical Officer. “If confirmed in larger datasets, we expect these results to align with FDA's guidance on overall survival as a primary endpoint for registrational studies.”

The patient with GBM presented at age 21 with an IDH-positive, methylated tumor. She received standard of care treatment of surgery, radiation, and temozolomide, as well as a single dose each of two experimental treatments. One year after diagnosis, the patient began PIC monotherapy. Median recurrence-free survival in this setting is 26 months and OS is 40 months. This patient has now reached 75 months of recurrence-free survival and is 87 months from surgical resection. She recently completed a master’s degree and works supporting other cancer patients.

The HCC patient presented at age 61 with a beta catenin mutated form of HCC, having progressed despite liver resection and treatment with an oncolytic virus and sorafenib. Upon enrollment in Geneos' GT-30 Phase 1b/2a trial, the patient was treated for two years with the combination of PIC and pembrolizumab, after which, per protocol, she was converted to PIC monotherapy. Median OS for such PD-1 treated HCC patients averages 14 months with three-to-four months of progression-free survival. This patient has now reached 60 months of recurrence-free survival and recently welcomed her first grandchild.

PICs are DNA-based tumor-infiltrating lymphocyte (TIL)-inducing agents containing up to 43 of a patient’s specific cancer neoantigens. They have been shown to have a 100% success rate in patients at inducing CD8+ activated cytotoxic T effector memory cells which traffic to tumors, the first such immunotherapeutic ever to achieve this metric. Unlike experimental mRNA-based personalized immunotherapeutics generally administered for no more than nine months, the tolerability of PICs supports uninterrupted treatment over years to maintain TIL response and minimize the odds of recurrence or progression.

Geneos is actively preparing to advance PIC monotherapy development in the upcoming GT-31 Phase 2b randomized, controlled clinical trial as adjuvant immunotherapy of patients with HCC.

About Geneos Therapeutics

Geneos Therapeutics is a clinical-stage biotherapeutics company developing personalized immunotherapies for cancer (PICs). The company's approach uses its proprietary DNA-based GT-EPIC™ platform to target neoantigens (abnormal mutations produced by cancer cells) from individual patient tumors to develop novel and uniquely personalized treatments for cancer. Planning is underway for a potentially registrational clinical trial in hepatocellular carcinoma in the adjuvant setting. For more information, please visit www.geneostx.com.

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