KaliVir Immunotherapeutics has raised USD 14 million in a Series A extension to advance its oncolytic immunotherapy VET3-TGI, as the company reported completion of the first intravenous dose cohort in its Phase I/Ib STEALTH-001 trial.
Company K Partners led the round, with participation from SV Investment, Flexus Partners, and existing investors including affiliates of Nextrans and Quad Investment Management. In conjunction with the close, Woo Young Kim of Company K Partners, Kwang Ha Jung of SV Investment, and JP Hong of Flexus Partners joined KaliVir's board of directors. Proceeds will support patient enrollment in the STEALTH-001 Phase I/Ib trial. KaliVir's initial Series A closed in March 2022 and was directed toward advancing VET3-TGI toward its investigational new drug application.
VET3-TGI is an oncolytic vaccinia virus engineered on KaliVir's proprietary Vaccinia Enhanced Template (VET) platform, designed to selectively replicate in tumor cells while expressing interleukin-12 and a transforming growth factor-beta inhibitor to stimulate immune responses and remodel the immunosuppressive tumor microenvironment. The STEALTH-001 study is a first-in-human, open-label dose-escalation and expansion trial evaluating VET3-TGI by intratumoral injection and intravenous infusion, as monotherapy and in combination with atezolizumab (Tecentriq), in patients with advanced, unresectable, or metastatic solid tumors. KaliVir said the study continues to progress through its dose-escalation phase as planned.
The VET platform has previously attracted two major pharma partnerships. In December 2020, KaliVir entered a worldwide exclusive licensing agreement with Astellas Pharma for VET2-L2, later designated ASP1012, carrying potential milestone payments of up to approximately USD 634 million; Astellas subsequently terminated its Phase I trial after enrolling approximately 15 patients. In May 2022, KaliVir entered a separate global exclusive licensing agreement with Roche for novel oncolytic vaccinia viruses derived from the VET platform, and in November 2025 the two companies announced a clinical trial collaboration and supply agreement for the atezolizumab combination arm within STEALTH-001.