Human Virus Helps to Treat Cancer Patients
18 May 2010 - A naturally-occurring harmless human virus given in combination with radiotherapy has shown significant benefit in a Phase I trial of patients with advanced cancer led by the ICR and The Royal Marsden.
The drug Reolysin, developed by Oncolytics, is based on a virus (reovirus type 3 Dearing) that is commonly found in humans’ respiratory and gastrointestinal tracts without causing any symptoms.
Laboratory tests on tumour cells showed Reolysin appeared to magnify the effects of radiotherapy, so researchers began a safety study on 23 patients with a range of solid tumours, including lung, colorectal, ovarian and skin cancer. Patients were given between two and six injections of Reolysin in escalating doses directly into their tumours, in combination with either a low dose (20Gy) or high dose (36Gy) of radiotherapy.
Of the 14 patients who received the treatment and were able to be evaluated, seven received low dose radiotherapy and tumours shrank in two cases and stabilised in five. In seven patients on high-dose radiotherapy, tumours shrank in five cases and stabilised in two.
Side-effects were generally mild and typical of patients receiving radiotherapy alone.
Patients in this trial had advanced disease that had stopped responding to traditional drugs, but for which radiotherapy could provide some pain relief. Chief Investigator Dr Kevin Harrington said the next step was to investigate the treatment combination in patients with newly-diagnosed cancers that would normally be treated with radiotherapy alone, to see whether it could improve cure rates.
