Oncolytic viral immunotherapy utilizes engineered viruses that can preferentially infect and kill cancer cells thereby generating de novo or boosting pre-existing anti-tumor immunity to combat cancer. Most oncolytic viruses are genetically modified to enhance tumor tropism or tumor targeting abilities, so that the virus’ virulence against non-tumor cells are significantly reduced. This allows the virus to replicate preferentially in tumor cells and leave normal cells unharmed. 

In addition to direct cell killing abilities, oncolytic viruses can also stimulate a pro-inflammatory environment within the host tumor as well as enhancing antigen release and recognition. This immune activation can counteract the immune evasiveness of tumors. In essence, the virus stimulates a systemic immune response that can combat cancer.



KALIVIR’s novel oncolytic viruses attack cancer in multiple ways to maximize replication of the viruses, spread of the viruses, expression of therapeutic payload matched to specific tumor immunophenotypes and/or unique biomarkers.

  • Start with Optimal virus strain for systemic delivery established in the clinic: Vaccinia virus;
  • Enhance vaccinia backbone with a proprietary combination of genetic modification to achieve maximize oncolytic killing and systemic delivery and spread;
  • Augment the vaccinia backbone with the ability to overcome immunosuppression and to activate anti-tumor immune response to attack tumors;
  • Express multiple therapeutic payloads to boost the anti-tumor immune response and that can synergize with other immuno-oncology therapeutics.

KALIVIR achieves this by using its proprietary VET™ Backbone technology to engineer vaccinia viruses. Learn more about the VET™ Backbone here.

KALIVIR’s product candidates are designed and constructed through rigorous testing and scientific evaluation utilizing the VET™ Backbone. We combine proprietary VET modifications and potent therapeutic transgenes to create unique product candidates that can effectively target a wide range of cancers.


Chief Medical Officer

Dr. James Burke is a University of California, San Francisco trained hematologist and oncologist who has led clinical development of gene therapy and oncolytic viruses for cancer for over 15 years including first in human through Phase 3 studies. Most recently, Dr Burke served as Chief Medical Officer of Sillajen (previously Jennerex) leading Phase 1-3 global development of a vaccinia virus platform for multiple cancers including HCC, RCC, and CRC.

The global Phase 3 registration trial targeting advanced HCC represents one of the largest oncolytic studies conducted to date spanning four continents including North America, Europe, Australia, and Asia. This Phase 3 study was the first oncolytic virus study conducted by a foreign biotech in China and one of only a few OV trials to ever be conducted in mainland China. Aside from Sillajen, Dr Burke led initial Phase 1-2 clinical development of Turnstone’s maraba virus prime-boost oncolytic virus program as CMO through initial studies and fund raising.

Dr Burke started his career at Cell Genesys spearheading early gene and immunotherapy studies including oncolytic adenovirus, lentivirus, AAV, and tumor vaccine programs. In addition to his biotechnology experience, Dr Burke directed studies as a clinical scientist including first in human studies in oncolytic viruses, tumor vaccines, as well as other cancer therapeutics in Phase 1-3 development.

Throughout his career he has had extensive interaction with global regulatory authorities and key academicians, led clinical development of numerous agents, built expert research teams, presented his research findings in key scientific journals and symposia, and led medical discussions and negotiations with external financing entities including venture capital and pharma.


Senior Vice President of Clinical Operations

Ms. Pelusio has more than 20 years of experience in drug development. Before joining KaliVir, she served as Senior Vice President of Clinical Operations at Turnstone Biologics, where she oversaw the advancement of candidate oncolytic viruses, cancer vaccines and adoptive cell therapies into clinical trials. Prior, Ms. Pelusio spent 10 years at SillaJen, Inc. (formerly Jennerex Biotherapeutics) where she led the introduction of oncolytic viruses into 17 countries across Phase I-III clinical trials. She holds an M.S. from the University of Florida and is pursuing an M.P.H. from Harvard University T.H. Chan School of Public Health.


Chief Scientific Officer

Stephen Thorne co-founded Kalivir in 2019 and currently serves as Chief Scientific Officer. He is a leader in the field of oncolytic viral immunotherapy and previously co-founded Western Oncolytics, BioEclipse and Jennerex, which is currently advancing Pexa-Vec through late-stage clinical trials.

Stephen was a Professor of Cell Biology and Immunology at the University of Pittsburgh and received his B.A. from Oxford University, UK and Ph.D. from Imperial College of London. Stephen has served in post doctorate roles at Surrey University, Cancer Research UK, and Stanford University and has authored more than 100 scientific publications in the field.


Chief Executive Officer

Helena has over 23 years of experience in the biotechnology industry having held leadership positions in operations, corporate affairs, business development and IP management primarily in oncolytic virotherapy development. Most recently, Helena served as Chief Business Officer at SillaJen Biotherapeutics, Inc. where she managed all operations including corporate and business development strategies, R&D strategy and intellectual property. Prior to joining SillaJen, Helena held the positions of VP of Corporate Affairs & IP at Jennerex Biotherapeutics and the Director of Business Development at MediGene. Helena received her B.S. in Biochemistry and her Ph.D. in Genetics from the University of British Columbia and her J.D. from Dalhousie University.