An international clinical study led by Canadian researchers has demonstrated that a drug called erlotinib increases survival in patients with advanced non-small cell lung cancer who typically have no other treatment options.
The study, funded by the Canadian Cancer Society and published in tomorrow's issue of The New England Journal of Medicine, involved 731 patients at centres in North and South America, Europe, Israel, New Zealand, Asia and South Africa. The patients had already received at least one or two regimens of chemotherapy and were randomly assigned to one of two groups: 488 patients received erlotinib and 243 received a placebo. The researchers found that treatment with erlotinib resulted in longer survival compared to the placebo. Patients who received erlotinib survived an average of 6.7 months, while patients on placebo survived an average of 4.7 months – a 42.5 per cent improvement. Of the patients receiving erlotinib, 31 per cent were alive after one year, compared to only 22 per cent of patients receiving placebo. Unlike many chemotherapies, erlotinib was generally well-tolerated and caused only minor side effects.
"This drug offers a new treatment option to patients at a time in their disease when they have no other options," says Dr. Frances Shepherd, the study's principal investigator, holder of the Scott Taylor Chair in Lung Cancer Research and medical oncologist at Princess Margaret Hospital, and professor of medicine at the University of Toronto. "Not only does erlotinib help them live longer, but it also improves their physical function, their quality of life, and it improves their symptoms of cough, shortness of breath and pain."
Dr. Barbara Whylie, CEO of the Canadian Cancer Society, says, "This is a welcome advance in the treatment of lung cancer, the most common cause of cancer death in Canada. Canadian researchers continue to be at the forefront of new advances in the fight against this disease and we are committed to continuing to support their outstanding efforts."
Also known commercially as Tarceva, erlotinib slows down tumour growth by interfering with a specific cellular pathway that promotes cell division. The drug interferes with epidermal growth factor receptors (EGFR), which receive an ongoing signal for the cells to divide, thus driving the cancer's growth. Erlotinib specifically targets EGFR to prevent the tumour from growing. This is the first drug of the EGFR inhibitors family demonstrated to improve survival. In November 2004, the U.S. Food and Drug Administration approved erlotinib for patients with advanced non-small cell lung cancer who had received at least one regimen of chemotherapy.
In a companion study, also published in tomorrow's issue of The New England Journal of Medicine, scientists led by Dr. Ming Tsao and Dr. Frances Shepherd at Princess Margaret Hospital assessed tumour biopsies from some of the patients on the study. They looked for gene mutations, gene copy number, and the expression of the epidermal growth factor receptor protein in the cancer cells. Their findings suggest that molecular testing is not necessary to identify appropriate patients for treatment with erlotinib.
Lung cancer is one of the most common forms of cancer worldwide, and it is the leading cause of death from cancer in North America. Non-small cell lung cancer is the most common type of lung cancer, accounting for almost 80 per cent of all cases. An estimated 22,200 Canadians will be diagnosed with lung cancer this year, and 19,000 will die of the disease.
The lung cancer clinical study was coordinated by the National Cancer Institute of Canada Clinical Trials Group, which is funded by the Canadian Cancer Society and based at Queen's University in Kingston, Ontario. It was also funded by OSI Pharmaceuticals Inc.
Princess Margaret Hospital and its research arm, Ontario Cancer Institute, have achieved an international reputation as global leaders in the fight against cancer. Princess Margaret Hospital is a member of the University Health Network, which also includes Toronto General Hospital and Toronto Western Hospital. All three are teaching hospitals affiliated with the University of Toronto.