A virus injected into the blood has been found to successfully target cancer cells throughout the body, a group of researchers has announced.

The virus, named JX-594, attacked tumours in 23 patients as part of a small trial, the researchers wrote in scientific journal Nature. Healthy tissue in the patients’ bodies was left unharmed.

The researchers, led by Professor John Bell from the University of Ottawa in Canada, wrote in the journal: “We hypothesised that a poxvirus, which evolved for blood-borne systemic spread in mammals, could be engineered for cancer-selective replication and used as a vehicle for the intravenous delivery and expression of transgenes in tumours.”

JX-594 selectively infects and replicates and expresses transgene products in cancer tissue after intravenous infusion in order to attack tumours all over the body.

“This platform technology opens up the possibility of multifunctional products that selectively express high concentrations of several complementary therapeutic and imaging molecules in metastatic solid tumours in humans,” the abstract concluded.

Infection prevented further tumour growth in six patients for a time, BBC News reports. However, the virus did not cure cancer.

Patients were given only one dose of the virus as the trial was designed to test the safety of JX-594.