Gene-Modified Virus Targets Tumor Cells

It extended survival of patients with metastatic colon cancer

THURSDAY, June 9, 2005 (HealthDay News) -- A genetically engineered anti-cancer virus shows promise as a treatment for people with colorectal cancer that has spread to the liver, researchers report.

"These results are very promising. The median survival time we saw among our patients was higher than you might expect among this group of patients," researcher Dr. Nancy Kemeny of Memorial Sloan-Kettering Cancer Center, New York, said in a prepared statement.

Her team tested an oncolytic herpes simplex virus (oHSV) in 12 patients with colorectal cancer that had spread to the liver and had proven resistant to first-line chemotherapy. The specific strain of the virus was NV1020, a weakened and altered form of herpes simplex virus type-1, which causes cold sores.

This specially engineered virus selectively destroys cancer cells without harming normal tissue.

In this Phase I study, the researchers gave the patients increasing doses of NV1020 delivered via a single 10-minute infusion. The virus treatment was followed by chemotherapy.

So far, the 12 patients' overall median survival time following the treatment is 23 months. One patient is still alive 30 months after the treatment.

"Our primary aim in this study was to test the safety of the virus. We were pleased to see that the virus could be administered safely in the hepatic [liver] artery without significant effects on the normal liver function," Kemeny said.

The findings were presented this week at the European Society for Medical Oncology Scientific and Educational Conference in Budapest, Hungary.

More information

The American Cancer Society has more about colorectal cancer.

SOURCE: European Society for Medical Oncology, news release, June 6, 2005
Consumer News