GenVivo, Inc. presented updated clinical and preclinical data for its novel cancer immunotherapies at the 2025 American Society of Gene + Cell Therapy (ASGCT) Annual Meeting in New Orleans. The clinical-stage biopharmaceutical company shared promising results from its ongoing Phase 1 trial of GEN2 and preclinical studies of GEN-1013, both utilizing the company's patented off-the-shelf vector platform.
GEN2 Shows Favorable Safety Profile in Phase 1 Trial
GEN2, a non-replicating mRNA vector, delivers a dual payload consisting of an enhanced prodrug-activating enzyme (HSV-eTK) and the cytokine GM-CSF. This combination stimulates the immune system against patient-specific tumor antigens, creating what the company describes as a "personalizing anti-tumor effect."
Early data from the ongoing Phase 1 dose escalation trial (NCT06391918) demonstrates that GEN2 is well-tolerated across intravenous dose ranges from 3.4E6 TU/kg to 2E8 TU/kg, with minimal toxicity and no Dose Limiting Toxicities (DLTs) reported to date.
"The safety profile we're seeing with GEN2 is particularly encouraging," said a GenVivo representative during the presentation. "We're observing clear signs of pharmacodynamic activity, including measurable GM-CSF levels and vector persistence in peripheral blood mononuclear cells during the dosing cycle."
Once the Recommended Phase 2 Dose (RP2D) is established, the protocol will expand to include three specific cancer types: hepatocellular carcinoma (HCC), hormone-positive breast cancer, and cutaneous malignancies. Assessment of paired biopsies is currently underway, and additional cohorts are planned to evaluate GEN2 in combination with checkpoint inhibitors for CPI-refractory melanoma and HCC.
GEN-1013 Demonstrates Potent Anti-Tumor Activity in Preclinical Models
The company also presented compelling preclinical data for GEN-1013, another non-replicating mRNA vector that delivers HSV-eTK alongside the immunostimulatory cytokine IL-12. This combination is designed to enhance cytolytic activity and tumor infiltration by natural killer cells and cytotoxic T lymphocytes without the systemic toxicities typically associated with IL-12 therapies.
In aggressive murine cancer models, GEN-1013 demonstrated remarkable efficacy. When administered intravenously to CT26 implanted tumor animals, 89% of treated subjects reached the predetermined study endpoint compared to just 11% of vehicle control animals. These studies utilized a mouse surrogate vector encoding mouse IL-12 (mIL-12), as human IL-12 is inactive in wild-type mice.
Notably, researchers observed immune activation in peripheral blood immune cells with both intravenous and intratumoral administration, correlating with the presence of intratumoral GEN-1013-transduced T cells. The therapy produced sufficient IL-12 to stimulate anti-tumor immune responses without approaching levels associated with IL-12 toxicity.
"What's particularly exciting about GEN-1013 is its ability to leverage localized IL-12 expression to stimulate potent immune responses while minimizing toxicity," explained a scientist involved in the research. "The administration was safe and well-tolerated in BALB/c mice at efficacious dose levels."
Novel Approach to Cancer Immunotherapy
Both therapies represent GenVivo's innovative approach to cancer treatment, which focuses on activating the patient's immune system against their own tumor antigens. This strategy differs from many current immunotherapies by potentially addressing the full spectrum of cancer-specific antigens rather than targeting a single marker.
"Traditional approaches often target a single antigen, which can lead to resistance as cancer cells evolve," noted a company spokesperson. "Our platform is designed to engage the immune system against multiple tumor-specific antigens simultaneously, potentially creating a more robust and durable response."
Development Timeline and Future Directions
GenVivo is continuing to advance both programs, with GEN2 progressing through its Phase 1 clinical trial and GEN-1013 undergoing comprehensive pharmacology and toxicology assessments to optimize dosing and scheduling. The company has announced plans for an Investigational New Drug (IND) filing for GEN-1013 by mid-2026.
In addition to these two lead programs, GenVivo's preclinical pipeline includes an in vivo CAR-T program, further expanding the company's portfolio of innovative cancer immunotherapies.
The company emphasizes its commitment to developing treatments that are not only effective but also practical for clinical use – rapidly deployed, easily administered, and personalizing despite being off-the-shelf products. The ultimate goal, according to GenVivo, is to increase cancer patient survival while improving quality of life.
About GenVivo
GenVivo (GVO) is a private, vertically integrated, clinical-stage biotechnology company based in San Marino, California. Founded to develop innovative gene delivery and immune stimulation therapies, the company focuses on activating patients' immune systems to treat cancer. GEN2, the company's first clinical candidate, is currently in a Phase 1 clinical trial in the US, while its preclinical pipeline includes GEN-1013 and an in vivo CAR-T program.
