Cancer is one of the most devastating diseases in the world, and researchers have been searching for a cure for decades. Recently, a new breakthrough has been made in the fight against cancer: a modified version of the herpes simplex virus, known as RP2, has shown promising results in a phase I trial. In this article, we'll take a look at the research behind this new treatment and explore how it could potentially offer a lifesaver to people with advanced cancers. The Institute for Cancer Research (ICR) in London recently announced that a patient in a trial testing a herpesvirus-based cancer treatment saw his cancer completely disappear and has remained cancer-free in the 15 months since his treatment began. This is not the first time that scientists have developed a modified herpesvirus to fight cancer; modified versions of HSV-1 have already proven successful against melanoma and brain cancer.
The drug is a weakened form of the cold sores virus (herpes simplex) that has been modified to kill tumors. When patients' tumors were biopsied before and after the injection, researchers found evidence that herpes was activating the immune system, with more immune cells present around the tumor. Dr. Harrington, one of the researchers involved in the study, explained that there were also approved medications available that could treat a herpes infection if the virus ended up replicating in places where it shouldn't, even though that hadn't happened in the tests.
He also noted that herpesviruses, which also include the viruses behind chickenpox and genital herpes, have developed a number of remarkable abilities, such as the trick of infecting and hiding in nerve cells, from which they emerge periodically to cause outbreaks of sores or skin rashes, such as shingles. Harrington told Medical News Today in an interview that the herpes virus really offered the “complete package” as a candidate for genetic modification to create such treatments. McFaddent added that one limitation of the use of herpes viruses as a basis for these treatments was that they had to be injected directly into the tumor, while it was expected that treatments based on smallpox viruses could be administered intravenously. A brief treatment with the virus, which is a specially modified version of the herpes virus that normally causes cold sores, seems to have eliminated cancer in some cases. The oncolytic herpes simplex virus (OHSV) can be genetically modified to attack cancer cells while preserving normal cells. The herpes simplex virus (HSV), which belongs to the Herpesviridae family, has a large dsDNA (152 kb) that is encapsulated within an enveloped icosahedron capsid. Viruses that have been used as oncolytic viruses include the herpes simplex virus, adenoviruses, smallpox viruses and the Coxsackie virus, and genetic modifications are used to introduce transgenes to improve their ability to kill cancer cells. The initial findings of this phase I trial are encouraging and suggest that this new genetically modified virus could be an effective treatment for advanced cancers.
Larger and longer studies will be needed to confirm these results, but experts are hopeful that this injection could ultimately offer a lifesaver to more people with advanced cancers.
