Transgene Presents Preclinical Data on Its PoxSTG-EEV Virus at SITC
In a press release published on November 3, 2026, the Strasbourg-based biotech detailed the preclinical data it will present in poster form at the annual meeting of the Society for Immunotherapy of Cancer (SITC), in Phoenix.
This work addresses what the company describes as the main challenges of oncolytic viruses: their systemic administration and their spread within the tumor.
A Chimeric Virus Compared with Conventional Vaccinia-Type Poxviruses
PoxSTG-EEV combines a chimeric viral vector, PoxSTG, with a formulation enriched in EEV (Extracellular Enveloped Virion), designed to generate and preserve the enveloped form of the virus. According to the company, this formulation aims to promote spread within the tumor and to strengthen the virus's resistance to the host immune system.
Compared with conventional vaccinia-type oncolytic viruses, PoxSTG-EEV demonstrated superior cytotoxic activity across multiple tumor cell models, as well as improved intratumoral spread.
The virus also retained its infectivity in the presence of active complement and neutralizing antibodies. In murine models, intravenous administration significantly reduced tumor growth and prolonged survival.
A Program Still at the Preclinical Stage, Upstream of Clinical Assets
Johann Foloppe, researcher and project leader at Transgene, stated that PoxSTG-EEV “forms the basis of Transgene’s new proprietary platform, EEVOLV, dedicated to the development of a new generation of clinical candidates.”
The program is upstream of the group’s clinical candidates, including TG4050, TG4070 (in Phase 1 in non-small cell lung cancer) and the oncolytic virus BT-001.
Katell Bidet-Huang, interim Chief Scientific Officer, considered that progress in systemic administration and intratumoral spread “could allow its therapeutic potential to be further exploited.” According to her, these data highlight the value of PoxSTG-EEV “in addressing some of these obstacles.”
These results come from cellular and murine models. In its forward-looking statements, the company reminds investors that there is no guarantee that the results of preclinical studies will be predictive of those of ongoing clinical trials.
The poster (abstract no. 1050), whose presentation had been announced in a press release dated October 5, 2026, will be presented on November 7, 2026, and posted online the same day on the websites of SITC and Transgene.
