Tuesday 18 May 2010
A naturally-occurring harmless human virus given in combination with radiotherapy has shown significant benefit in patients with advanced cancer, according to results of an early trial published online today in the journal Clinical Cancer Research.
Reolysin is a new drug developed by Oncolytics Biotech Inc with preclinical and clinical studies conducted at The Institute of Cancer Research (ICR) and The Royal Marsden Hospital that can be injected directly into patients’ tumours. It is based on a virus (reovirus type 3 Dearing) that is commonly found in humans’ respiratory and gastrointestinal tracts without causing any symptoms.
Until now, trials of virus treatments injected in cancer patients have found them to be safe but with only limited effectiveness. Meanwhile, scientists have been looking for approaches that would amplify the effects of radiotherapy in a process known as radiation sensitisation, giving a greater effect than simply the sum of the two treatments.
Laboratory tests on tumour cells showed Reolysin appeared to magnify the effects of radiotherapy, so researchers began a Phase I study on 23 patients with a range of solid tumours, including lung, colorectal, ovarian and skin cancer. They were given between two and six injections of Reolysin in escalating doses, in combination with either a low dose (20Gy) or high dose (36Gy) of radiotherapy, at either The Royal Marsden Hospital in London or St James’s University Hospital in Leeds.
The study primarily assessed whether the treatment combination was safe, and found side-effects were generally mild and typical of patients receiving radiotherapy alone. However clinicians were also able to measure tumour response for 14 patients, and found tumours for all 14 patients either shrank or stabilised.
Of the seven patients who received low dose radiotherapy and were able to be evaluated, 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. One patient had a large tumour mass of his parotid gland and it shrank enough to be surgically removed. Another patient with metastatic melanoma was still alive 17 months after treatment commenced.
The study also tested patients’ blood, stools, urine and sputum for viral RNA, and found the virus was not shed after treatment. This means people could be given the drug as outpatients as no risk was found that they could transmit the virus to others.
Patients in this trial had advanced disease that had stopped responding to traditional drugs, but for which radiotherapy could provide some pain relief. Dr Kevin Harrington from the ICR and The Royal Marsden 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.
“The absence of any significant side-effects in this study is extremely reassuring for future trials in patients receiving radiotherapy with the aim of curing their cancer,” Dr Harrington said.
Dr Brad Thompson, President and CEO of Oncolytics, added: “We believe that this study clearly demonstrates that the combination of low dose radiation and Reolysin is well tolerated and that the very high response rate warrants further investigation.”
The study was funded by Oncolytics Biotech Inc.
-ENDS-
Media Contact: ICR Science Press Officer Jane Bunce at [email protected] or 0207 153 5106
Notes to editors:
Two-Stage Phase I Dose Escalation Study of Intratumoural Reovirus Type 3 Dearing and Palliative Radiotherapy in Patients with Advanced Cancers is published online first in Clinical Cancer Research on Tuesday May 18.
The Institute of Cancer Research (ICR)
• The ICR is Europe’s leading cancer research centre
• The ICR has been ranked the UK’s top academic research centre, based on the results of the Higher Education Funding Council’s Research Assessment Exercise
• The ICR works closely with partner The Royal Marsden NHS Foundation Trust to ensure patients immediately benefit from new research. Together the two organisations form the largest comprehensive cancer centre in Europe
• The ICR has charitable status and relies on voluntary income, spending 95 pence in every pound of total income directly on research
• As a college of the University of London, the ICR also provides postgraduate higher education of international distinction
• Over its 100-year history, the ICR’s achievements include identifying the potential link between smoking and lung cancer which was subsequently confirmed, discovering that DNA damage is the basic cause of cancer and isolating more cancer-related genes than any other organisation in the world
For more information visit www.icr.ac.uk
The Royal Marsden Hospital
The Royal Marsden opened its doors in 1851 as the world’s first hospital dedicated to cancer treatment, research and education. Today, together with its academic partner, The Institute of Cancer Research, it is the largest and most comprehensive cancer centre in Europe treating over 40,000 patients every year. It is a centre of excellence, and the only NHS Trust to achieve the highest possible ranking in the Healthcare Commission’s Annual Health Check for the fourth year in a row. Since 2004, the hospital’s charity, The Royal Marsden Cancer Campaign, has helped raise over £50 million to build theatres, diagnostic centres, and drug development units. Prince William became President of The Royal Marsden in 2007, following a long royal connection with the hospital. For more information, visit www.royalmarsden.nhs.uk
Oncolytics Biotech IncOncolytics is a Calgary-based biotechnology company focused on the development of oncolytic viruses as potential cancer therapeutics. Oncolytics’ clinical program includes a variety of human trials including a Phase III trial in head and neck cancers using REOLYSIN, its proprietary formulation of the human reovirus. For further information about Oncolytics, please visit: www.oncolyticsbiotech.com