The test was evaluated alongside a Phase I clinical trial of an experimental drug known as a c-MET inhibitor, the results of which are published today in the Journal of Clinical Oncology.
Trial lead investigator Professor Johann de Bono from the ICR and The Royal Marsden says: “To assess whether a drug is working doctors currently rely on techniques such as imaging or biopsy, which are slow to show results and may lead to other complications.
“These blood tests could be used at a much earlier stage to confirm that the drug is benefiting a particular patient; and if not they can be quickly moved to an alternative therapy. If larger-scale trials confirm these results, it will help ensure patients receive the best possible treatment.”
The drug being trialled, developed by pharmaceutical companies ArQule and Daiichi Sankyo and known as tivantinib (formerly ARQ 197), is a new-generation treatment designed to target the genetic defects responsible for causing the cancer, in comparison to old-style drugs that do not differentiate between cancer cells and other fast growing cells. It therefore has the potential to kill cancer cells with fewer side-effects, but will not be effective for all cancer patients.
A number of clinical trials are being carried out around the world to test tivantinib’s effectiveness. In conjunction with one such trial held at The Royal Marsden, ICR scientists set out to find a simple way to establish which patients would respond to the drug.
The trial, which started in April 2007, involved 51 patients with a range of solid tumours including prostate cancer, melanoma, gastrointestinal cancers and breast cancer.
Side-effects were generally mild, and included fatigue, nausea and vomiting. Although the trial was mainly designed to assess the drug’s safety, the researchers observed that 14 patients’ cancer stabilised for at least four months, while tumours shrank for two patients, one with metastatic gastric cancer and the other with Merkel cell carcinoma.
Patients’ blood was taken before and after treatment and their levels of circulating tumour cells (CTCs) and circulating endothelial cells (CECs) were measured. CTCs are cancer cells that have broken away from an existing tumour and entered the blood stream, and are thought to be an indicator of disease progression. CECs are a measure of whether blood vessels are functioning; and are linked to tumour progression as cancers rely on new blood vessels forming to enable them to spread.
The ICR scientists measured a drop in CTCs in around six of ten patients with initially detectable levels, suggesting a potential benefit for these patients. CECs fell in around half of the patients with initially detectable levels, providing preliminary evidence of an effect on tumour blood vessel formation in these people.
Tests for CTCs and CECs are also being incorporated into trials for other cancer drugs and it is hoped that ultimately they may be widely used to measure patients’ prognoses.
Media Contact: Science Communications Manager Jane Bunce on 0207 153 5106 or after hours 077217 47900
Notes to editors:
Phase I Trial of a Selective c-MET Inhibitor ARQ 197 Incorporating Proof of Mechanism Pharmacodynamic Studies is published today in the Journal of Clinical Oncology with lead author Dr Timothy Yap from the ICR and The Royal Marsden.
Tivantinib was discovered by ArQule with further development in conjunction with Daiichi Sankyo. Tivantinib has progressed to later stage testing for a range of cancer types, both as a single agent and in combination with other drugs. The most advanced trial, a Phase III trial of tivantinib in combination with erlotinib, began enrolling patients with non-small cell lung cancer in January after an earlier Phase II trial found the combination therapy gave a significantly longer overall survival time compared to a placebo plus erlotinib.
ArQule Inc provided the main funding for the study with additional support from Cancer Research UK. Further resources were provided by the Experimental Cancer Medicine Centre, the National Institute for Health Research Biomedical Research Centre and the Cancer Research UK and Engineering and Physical Sciences Research Council Cancer Imaging Centre, all located at the ICR and The Royal Marsden.
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 90 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
- The ICR is home to the world’s leading academic cancer drug development team. Several important anti-cancer drugs used worldwide were synthesised at the ICR and it has discovered an average of two preclinical candidates each year over the past five years
For more information visit www.icr.ac.uk