KaliVir Immunotherapeutics Announces Clinical Trial Collaboration and Supply Agreement with Roche to Evaluate VET3-TGI in Combination with Atezolizumab (Tecentriq®) in Advanced Solid Tumors

Audio By Carbonatix

PITTSBURGH--(BUSINESS WIRE)--Nov 19, 2025--

KaliVir Immunotherapeutics, Inc., a clinical-stage biotechnology company developing cutting-edge, multi-mechanistic oncolytic immunotherapies, today announced a clinical trial collaboration and supply agreement with Roche to evaluate VET3-TGI, a novel oncolytic immunotherapy developed using KaliVir’s proprietary Vaccinia Enhanced Template (VET™) platform, in combination with Roche’s atezolizumab (Tecentriq®).

The collaboration will support the expansion of KaliVir’s ongoing STEALTH-001 (NCT06444815) Phase 1a/1b clinical study evaluating VET3-TGI in patients with advanced or metastatic solid tumors. Under the terms of the agreement, Roche will supply atezolizumab for use in combination with VET3-TGI across multiple dosing cohorts.

VET3-TGI is KaliVir’s lead oncolytic immunotherapy candidate, designed to directly destroy tumor cells while activating a potent immune response through a proprietary payload that includes interleukin-12 (IL-12) and a TGF-β inhibitor. Combining VET3-TGI with atezolizumab aims to amplify immune activation and reshape the tumor microenvironment, with the goal of broadening and deepening clinical benefit for patients with a range of solid tumors.

"This clinical collaboration with Roche allows us to build on the promising clinical and preclinical data by expanding the evaluation of VET3-TGI beyond monotherapy into combination therapy with an established checkpoint inhibitor,” said Helena Chaye, CEO of KaliVir Immunotherapeutics. “Partnering with Roche, a global leader in oncology, represents an important step toward advancing innovative therapeutic strategies and exploring the full potential of this novel combination for patients with advanced solid tumors."

About VET3-TGI and the STEALTH-001 Study

VET3-TGI is a novel oncolytic virus developed using KaliVir’s proprietary VET™ platform, designed to selectively replicate in tumor cells, stimulate local immune responses and remodel the immunosuppressive tumor microenvironment through the expression of IL-12 and a TGFβ inhibitor. The STEALTH-001 study is a first-in-human, open-label, dose escalation and expansion Phase 1a/1b trial assessing both intratumoral and intravenous administration of VET3-TGI. The STEALTH-001 trial is a dose escalation and expansion study evaluating VET3-TGI administered through direct IT injection and IV infusion. The trial is evaluating VET3-TGI as a monotherapy and in combination with a checkpoint inhibitor in patients with pathologically confirmed, advanced, unresectable or metastatic solid tumors. The study continues to progress as planned through its dose escalation phase.

About KaliVir Immunotherapeutics, Inc.

KaliVir Immunotherapeutics is a clinical-stage biotechnology company at the forefront of developing next-generation oncolytic immunotherapies. By harnessing the unique advantages of the vaccinia platform, KaliVir engineers optimized viral backbones to create innovative candidates for cancer treatment. The Company's proprietary Vaccinia Enhanced Template (VET™) platform integrates multiple genetic modifications, allowing for the systemic delivery of oncolytic vaccinia candidates and the targeted expression of therapeutic transgenes within tumors.

Headquartered in Pittsburgh, Pennsylvania, KaliVir is committed to revolutionizing cancer treatment. For more information, visit www.kalivir.com.

Tecentriq® (atezolizumab) is a registered trademark of Genentech, a member of the Roche Group.

View source version on businesswire.com:https://www.businesswire.com/news/home/20251119270996/en/

CONTACT: Media Contact:

Lauren Arnold

LA Communications

[email protected]

KEYWORD: PENNSYLVANIA UNITED STATES NORTH AMERICA

INDUSTRY KEYWORD: SCIENCE OTHER SCIENCE BIOTECHNOLOGY RESEARCH PHARMACEUTICAL ONCOLOGY HEALTH CLINICAL TRIALS

SOURCE: KaliVir Immunotherapeutics, Inc.

Copyright Business Wire 2025.

PUB: 11/19/2025 08:00 AM/DISC: 11/19/2025 08:01 AM

http://www.businesswire.com/news/home/20251119270996/en