An altered herpes virus is being tested in mesothelioma patients, and the results show that it can stabilize the growth of mesothelioma tumors. Half of the patients given the virus responded to the treatment, which is very promising. Thirteen patients were injected with a version of HSV (herpes causing virus) that seeks out cancer cells. The virus has been altered so that it cannot replicate in non-dividing cells. It is very destructive, especially in cancer cells, so mesothelioma is a good candidate for this treatment. The virus has also been altered so that it cannot cause herpes. This is done by weakening the virus, also known as attenuating it. This is not the first study of this virus. Other studies have shown that it stimulates the immune system to fight cancer.
The study is being done at the University of Sheffield in the United Kingdom. Thirteen patients with pleural mesothelioma were injected with the virus. Five of the patients had received chemotherapy to treat their cancer and the other eight had not received any chemotherapy. The patients did not have a choice to have surgery. Doctors injected the altered herpes virus into bodies using a pleural catheter. Three of the patients received only one dose, three received two doses, and seven received four doses. The treatment was well tolerated by the patients but there were a few virus-related adverse events and toxicities from no dose limiting.
The treatment stimulated the patients’ own immune systems to fight their mesothelioma. The virus did not shrink any tumors so there are limitations to the treatment. It did stop the tumors from growing for two months in half of the patients though. The results of the study allowed the researchers to conclude that the altered herpes virus has an anti-tumor immune response in pleural mesothelioma patients.
Mesothelioma is an incurable cancer caused by asbestos exposure. Since there is no cure, many clinical trials are being done to find better ways to treat it. Without these clinical trials, mesothelioma treatment would not be where it is today. If this clinical trial is found to be effective, it could be used to treat mesothelioma and improve sufferers’ lives.
