Virus Shows Some Cancer-Killing Abilities

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Previous viruses have shown cancer-fighting (oncolytic) ability. But, because the human immune system is primed to fend off viruses, oncolytic viruses may have trouble surviving until they reach their intended target -- the spreading cancer cells. To avoid this, researchers have been directly injecting viruses into tumors. But, according to Hallenbeck, if you're able to access a tumor well enough to inject the virus into it, that tumor can probably be well treated with surgery or radiation.

The SVV virus appears to be able to reach metastatic cancer cells without being inactivated by the immune system cells present in blood. With this virus, Hallenbeck is hoping to be able to track down metastatic cancer cells that can't easily be detected.

And, in cell lines, the virus appears to be effective at treating small-cell lung cancer and some pediatric cancers, without being inactivated by the immune system. The researchers also tested the virus in mice with deficient immune systems and found it was able to eradicate small-cell lung cancer in 10 out of 10 mice tested and knock out eye cancer in five out of eight mice tested.

"It is unclear whether these results from immune-deficient mouse models would be similar to those of patients with metastatic cancer. In particular, it is unknown whether the patients' immune system would reduce the effectiveness of SVV-001," the study authors wrote.

Hallenbeck said the phase I trial is expected to be completed some time next year. If all goes well in that trial, testing of the virus will move on to trials designed to measure effectiveness, he said.

More information

To learn about cancer advances made in recent years, visit the U.S. National Cancer Institute.