Cancer-fighting version of herpes shows promise in early human trials

Illustration of the herpes simplex virus.

Illustration of the herpes simplex virus.
Clarification: stock struggle (stock struggle)

New research this week suggests that scientists may be able to turn an ancient bacterial foe into a cancer-fighting ally. In preliminary data from a phase 1 trial, a genetically modified version of the herpes virus has shown promise in treating hard-to-remove tumors, with one patient experiencing complete remission for 15 months now. However, more research will be needed to confirm the success of early treatment.

The viral treatment is known as RP2 and is a genetically modified strain of herpes simplex 1, the virus responsible for most cases of oral herpes in humans, as well as some cases of genital herpes. Developed by Replimune, RP2 is Designer To act on two fronts. When injected directly into a tumor, the virus is supposed to selectively infect and kill some cancer cells. But it also blocks the expression of a protein known as CTLA-4 that these cells produce, hijacking their organs to produce another molecule called GM-CSF. The end result of these cellular changes is the weakening of the cancer’s ability to hide and fend off the immune system.

In a phase 1 trial by scientists at the Institute of Cancer Research and the Royal Marsden NHS Foundation Trust in the UK, RP2 was given as monotherapy to nine patients with advanced cancers who had failed to respond to other treatments; It was also given in combination with another immunosuppressant to 30 patients. Three patients on RP2 alone seemed to respond to the treatment, meaning their cancers shrank or stopped growing, and seven patients responded in the combination therapy. One patient in particular, with a type of cancer along his salivary gland, did not show signs of cancer for at least 15 months after treatment with RP2 alone. No life-threatening adverse events were reported in the trial, and the most common symptoms after treatment were fever, chills, and other influenza-like illnesses.

the findings, Foot This week at the 2022 European Society of Medical Oncology (ESMO) conference, it’s preliminary, as it has yet to be screened through the formal peer review process. They are also based on a very small sample size, which means that any results should be taken with caution. But the Phase 1 trials aren’t meant to show that the treatment is effective, only that it’s safe enough for humans to take. So the fact that some people with seemingly incurable cancers actually seem to respond to RP2, the team says, is a very good sign that it could live up to its potential.

“Our study shows that a genetically engineered virus that kills cancer can deal a one-to-two blow against tumors — destroying cancer cells directly from within while also invoking the immune system against them,” said lead author Kevin Harrington, professor of biological cancer. Treatments at the Institute for Cancer Research, in a statement from the organisation.

لقد كان العلماء optimistic About anti-cancer viruses for a long time. But it is only recently that this hope has finally begun to bear fruit. In 2015, it was the first viral treatment agreed In the United States for some advanced cases of skin cancer. Last May, scientists in California launched the first phase of a clinical trial of their anti-cancer virus Vaccinia. else comp They develop their own candidates, either on their own or in combination with other treatments. Replimune is developing two other candidates based on a modified herpes virus.

While many experimental treatments eventually fail to cross the finish line and reach the public, it is at least possible that some of these viruses will one day become the new standard treatment for cancer.