Oncolytic Viral Therapies Require Shielding to Destroy Tumors

Share this content:

(ChemotherapyAdvisor) – Oncolytic reoviruses require a little help from host blood cells in order to evade the host humoral immune response, according to a multinational team of researchers. The conclusion is based on a study entitled “Cell Carriage, Delivery, and Selective Replication of an Oncolytic Virus in Tumor in Patients,” which has been published in the June issue of Science Translational Medicine.

In this study, the investigators aimed to evaluate how oncolytic reoviruses evade the antiviral immune response, as well as how they are preferentially delivered to, and replicated in, tumors over normal tissue. Prior to this study, none of these aspects had been investigated in humans. Colorectal cancer patients were treated with a single cycle of intravenous reovirus prior to previously-planned resection of liver metastases.

Following administration, the reovirus was genome-tracked, being detected in plasma, and blood mononuclear cells, granulocytes, and platelets. “Despite the presence of neutralizing antibodies before viral infusion in all patients, replication-competent reovirus that retained cytotoxicity was recovered from blood cells but not from plasma, suggesting that transport by cells could protect virus for potential delivery to tumors,” the investigators wrote. Malignant cells expressed higher levels of reoviral protein than normal tissue, confirming preferential infection of tumor tissue. Replicating virus was also recovered from tumor tissues but not normal liver. 

Based on their findings, the investigators concluded that systemic administration via host cell carriage is necessary to shield a reoviral-based oncolytic vaccine from neutralization by antibodies in vivo, and thus allow for entry into, and destruction of, tumors. 

Abstract

Related Resources

You must be a registered member of Cancer Therapy Advisor to post a comment.

Sign Up for Free e-newsletters



Regimen and Drug Listings

GET FULL LISTINGS OF TREATMENT Regimens and Drug INFORMATION

Bone Cancer Regimens Drugs
Brain Cancer Regimens Drugs
Breast Cancer Regimens Drugs
Endocrine Cancer Regimens Drugs
Gastrointestinal Cancer Regimens Drugs
Gynecologic Cancer Regimens Drugs
Head and Neck Cancer Regimens Drugs
Hematologic Cancer Regimens Drugs
Lung Cancer Regimens Drugs
Other Cancers Regimens
Prostate Cancer Regimens Drugs
Rare Cancers Regimens
Renal Cell Carcinoma Regimens Drugs
Skin Cancer Regimens Drugs
Urologic Cancers Regimens Drugs