New trial to test cancer smart drugs

Nov 29 2004

Cancer Research UK has launched a major new clinical trial for the most common form of lung cancer, to test the effectiveness of one of the new generation of 'smart' cancer drugs as a first line treatment.

Researchers at more than 70 centres across the UK will test out a drug called Tarceva, which is taken by mouth as a simple white pill and targets a molecule with a key role in the growth and extended lifespan of cancer cells.

The pioneering final phase trial will not only evaluate a potentially exciting new therapeutic approach for advanced lung cancer – currently very difficult to treat – but will also collect essential information aimed at targeting the drug at the patients who will benefit most.

As part of the trial, scientists at University College London will carry out one of the largest pharmacogenomic studies ever conducted, to match treatments to the genetic profiles of tumours.

The trial is being funded by Cancer Research UK and coordinated by the Cancer Research UK and UCL Trials Centre in London. Doctors will aim to recruit 664 patients with advanced non-small cell lung cancer, which accounts for three quarters of cases of the disease.

The study will start this week, with half the patients randomised to receive Tarceva.

Chief investigator Dr Siow Ming Lee, consultant at the UCL Hospital Trust and clinical researcher for Cancer Research UK, says: "Conventional chemotherapy is of limited use against advanced lung cancer.

"Tumour cells quickly become resistant to treatment, while chemotherapy doesn't properly distinguish between cancerous cells and healthy ones and has too many side effects for many very ill lung cancer patients to cope with.

"In the new trial, we're testing a rather more subtle approach to treating lung cancer, by targeting a molecule which is more important for cancer cells than for their healthy counterparts.

"Carrying out large-scale trials like this will play a crucial role in evaluating the new smart cancer drugs and getting the most effective ones into the clinic as soon as possible."

Tarceva selectively blocks the action of a molecule called the epidermal growth factor receptor (EGFR), which relays instructions to cells to grow and divide, and to ignore signals telling them to die.

EGFR seems to be particularly important for the growth and survival of some cancer cells and large amounts of the molecule are often present in the cells of non-small cell lung cancers, sometimes in a mutated, over-active form.

After treatment, researchers will analyse patients' tumour and blood samples, to determine whether the type or amount of EGFR detected affects the way a patient responds to treatment. This could pave the way for a test to predict which patients are most likely to benefit from the drug.

A recent Canadian trial tested Tarceva against non-small cell lung cancer, but in patients who had already been heavily treated with chemotherapy. The results were positive, suggesting the drug could potentially extend the amount of time patients lived.

Dr Lee is optimistic for the prospects of the new Phase III study, which will use the drug as a first-line treatment in patients diagnosed with advanced lung cancer who are considered unsuitable to receive chemotherapy.

Dr Lee explains: "By the time they are referred to cancer experts, some lung cancer patients have widespread disease and are too unwell to undergo chemotherapy. For this new trial, we will test the role of a highly selective, non-cytotoxic drug to treat lung cancer patients who are currently not offered any forms of systemic treatment.

"Tarceva has minimal side effects and patients should be able to cope with it much better than they would with conventional chemotherapy."

Professor Robert Souhami, Cancer Research UK's Director of Policy and Communication, says: "We are seeing important changes in our approach to the treatment of some cancers, with researchers beginning to test out more specific anti-cancer therapies in place of broad-action chemotherapy.

"The new trial will test out one such selective anti-cancer agent, which we hope will make some headway against a disease which is notoriously difficult to treat. By providing a treatment which patients can take at home in simple pill form, it may also make a significant contribution to improving the quality of life of very ill cancer patients."