A cell-based platform to potentiate oncolytic virus: Potential approach for cancer therapies.

Authors

null

Duong Nguyen

Calidi Therapeutics, San Diego, CA

Duong Nguyen, Alberto Gomez, Ashley Alamillo, Forrest Neuharth, Ivelina Minev, Thomas Herrmann, Barbara Haertl, Laura Edith Schneider, Boris Minev, Dobrin Draganov, Antonio F. Santidrian

Organizations

Calidi Therapeutics, San Diego, CA, Calidi Biotherapeutics, San Diego, CA, StemVac, Bernried, Germany, Stemvac, Bernried, Germany

Research Funding

Pharmaceutical/Biotech Company
Calidi Biotherapeutics.

Background: Oncolytic virotherapy has been pursued by multiple companies and institutions with few candidates reaching the clinic and demonstrating limited efficacy. The therapeutic potential of oncolytic viruses can be severely restricted by innate and adaptive immune barriers. To overcome this obstacle, we load and protect tumor selective CAL1 oncolytic vaccinia virus into adipose-derived stem cells (AD-MSC) to generate a new therapeutic agent called SNV1(SuperNova1). Methods: SNV1s were generated by incubating AD-MSC with CAL1 virus. SNV1 was analyzed for its ability to kill cancer cell lines and protect virus in the presence of active neutralizing antibodies and complement. In animals, SNV1 was intratumorally injected in various xenograft and syngeneic models. Viral biodistribution was also evaluated by PCR. Immune infiltration were analyzed using flow cytometry. Results: Compared to the naked virus, SNV1 showed improved protection against the humoral barriers and efficient eradication of various human cancer cell lines in vitro. Intratumoral SNV1 treatment showed statistically significant and potentiated tumor growth inhibition compared to control or CAL1 naked virus treatment in all tested models (prostate, breast, melanoma, colon, and prostate cancers). Importantly, local administration of SNV1 induced systemic therapeutic effects. Five days after SNV1 administration, tumor infiltrating lymphocytes (TILs) from both treated and untreated tumors showed increased CD4 and CD8 T-cell populations. As well as decreased frequency of Tregs, and improved effector to Treg ratios, which was associated with inhibition of tumor growth at the treated tumor site and also at distant untreated sites. Ongoing and persistent virus infection could be detected in the treated tumor as late as 15 days after administration. Conclusions: This study demonstrates the ability of our cell-based platform to protect and potentiate oncolytic vaccinia virus by circumventing the innate and adaptive immune barriers, resulting in enhanced oncolytic virotherapy. These findings provide fundamental rationale for the development of cell-based platforms to maximize the therapeutic potential of various oncolytic viruses.

Disclaimer

This material on this page is ©2024 American Society of Clinical Oncology, all rights reserved. Licensing available upon request. For more information, please contact licensing@asco.org

Abstract Details

Meeting

2020 ASCO-SITC Clinical Immuno-Oncology Symposium

Session Type

Poster Session

Session Title

Poster Session A

Track

Breast and Gynecologic Cancers,Developmental Therapeutics,Genitourinary Cancer,Head and Neck Cancer,Lung Cancer,Melanoma/Skin Cancers,Gastrointestinal Cancer,Combination Studies,Implications for Patients and Society,Miscellaneous Cancers,Hematologic Malignancies

Sub Track

Vaccines and Oncolytic Viruses

Citation

J Clin Oncol 38, 2020 (suppl 5; abstr 21)

Abstract #

21

Poster Bd #

C3

Abstract Disclosures

Similar Abstracts

First Author: Eduardo Richardet