Intravenous delivery of a cancer-targeting virus is successful in destroying cancer cells that have spread throughout the body, according to research to be presented at the American Society of Gene & Cell Therapy 13th Annual Meeting.

A recent study tested 23 patients with metastasized colorectal, skin, ovarian and lung cancers. Patients received a single intravenous treatment at one of five dose levels. In 75 percent of patients who received the highest doses, the therapy reached and replicated within tumors throughout the body, effectively stopping cancer growth. Some patients on the lower doses also saw disease stabilization.

All dose levels were well tolerated, with patients experiencing only mild side effects, such as flu-like symptoms.

“This is the first time that we’ve been able to treat patients intravenously and had proven success in targeting and destroying metastatic cancers in the body with an armed oncolytic virus product,” said David H. Kirn, MD. “This opens up a whole new world of systemic approaches to therapy.”

Gene therapy has been used before to fight cancer, but previous treatments were limited to localized tumors. Intravenous delivery allows for whole-body treatment.

Kirn said the study opens the door to retest existing genetic or protein treatments that had previously been limited to patients with localized tumors. Researchers will begin a Phase III trial later this year in patients with liver cancer.