Thirty terminally ill liver cancer patients were treated with a genetically engineered virus and it was found that the virus destroyed the tumors and inhibited the development of new ones thereby significantly prolonging the lives of the patients.
A genetically modified organism is an organism whose genetic material has been modified using certain techniques to incorporate certain desiable characters in it (like pathogen resistance in case od crop plants) or to remove certain undesiable characters (like pathogenecity etc. in case of microbes).
So far, among the patients with an advanced stage of cancer, 16 had been given high doses of the vaccine Pexa-Vec or JX-594 and 14 had been given low doses and this increased their life span by a few months to over a year.
“For the first time in medical history, we have shown that a genetically-engineered virus can improve survival of cancer patients,” said David Kirn, the co-author of the study.
This trial with the new vaccine was reported in the Nature Medicine and is said to be a promising field in the treatment of the advanced stages of cancer. As mentioned in the report, according to the authors, “Despite advances in cancer treatment over the past 30 years with chemotherapy and biologics, the majority of solid tumours remain incurable once they are metastatic (have spread to other organs).”
Pexa-Vec, that has been genetically engineered from the vaccinia virus,a virus used for the eradication of smallpox, is designed in a way that it boosts the host’s immune response in addition to targetting and killing tumor cells itself. It is now being tested for other kinds of cancers as well.