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Novel Viral Therapy May Benefit Cancer Patients
Last Updated: September 01, 2011

A novel, intravenously-delivered viral therapy appears to selectively infect and replicate in tumor cells without invading and harming healthy tissue in individuals with advanced cancer, according to a study published online Aug. 31 in Nature.

THURSDAY, Sept. 1 (HealthDay News) -- A novel, intravenously-delivered viral therapy appears to selectively infect and replicate in tumor cells without invading and harming healthy tissue in individuals with advanced cancer, according to a study published online Aug. 31 in Nature.

Caroline J. Breitbach, Ph.D., of Jennerex Inc. in San Francisco, and colleagues administered a single intravenous infusion of a virus called JX-594, at one of five dose levels, in 23 patients with advanced cancers that had metastasized to multiple organs and failed to respond to standard treatments. Biopsies were obtained eight to 10 days later.

The investigators found that seven of eight patients (87 percent) who received the two highest dose levels showed evidence of viral replication in their tumor, without impact on normal tissue. All these patients demonstrated tumor-selective expression of a foreign gene that was engineered into the virus to help with detection. The virus was well tolerated at all dose levels. The most common adverse events were influenza-like symptoms that lasted for less than 24 hours.

"We are very excited because this is the first time in medical history that a viral therapy has been shown to consistently and selectively replicate in cancer tissue after intravenous infusion in humans," co-author John Bell, Ph.D., of the Ottawa Hospital Research Institute and the University of Ottawa, said in a statement. "Intravenous delivery is crucial for cancer treatment because it allows us to target tumors throughout the body as opposed to just those that we can directly inject. The study is also important because it shows that we can use this approach to selectively express foreign genes in tumors, opening the door to a whole new suite of targeted cancer therapies."

The study was funded by Jennerex Inc.; two authors disclosed financial relationships Jennerex.