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An international research led by The Chinese Univeristy of Hong Kong (CUHK) has confirmed a novel targeted therapy which is twice as effective as the current standard treatment for ALK-positive lung cancer because it doubles the progression-free survival time, and at the same time, lowers the chance of brain metastases.  ALK is a gene that produces a protein that helps cancer cells grow and spread, according to the American Cancer Society (ACS).

This global study, led by Prof. Tony MOK, will set the new standard of care for initial treatment for ALK-positive lung cancer patients throughout the world.  The findings of this study were just published in the leading international medical journal The New England Journal of Medicine on 7 June 2017, and presented at the 2017 American Society of Clinical Oncology (ASCO) Annual Meeting on the same day.

‘Alectinib’ halts lung cancer growth for 15 months longer than current standard therapy 

Lung cancer is the most common cancer in the world, accounting for 1.6 million deaths every year. It is also the leading cause of cancer deaths in Hong Kong, with over 4,000 new cases every year.  Of these, 80% suffer from non-small-cell lung cancer (NSCLC) and about 5% of these cases are ALK-positive.  ‘Crizotinib’ is the current standard of care, while Alectinib (a second generation ALK inhibitor) is approved for usage upon crizotinib failure.  Alectinib is a more potent, next generation inhibitor of ALK and this is the first global study to compare the two targeted therapies.

Prof. Tony Shu Kam MOK, Li Shu Fan Medical Foundation Professor of Clinical Oncology and Chairman of the Department of Clinical Oncology of the Faculty of Medicine of CUHK, explained, ‘Although the majority of patients respond well to Crizotinib initially, the cancer typically starts growing again within 12 months.  Also, like many drugs available for lung cancer treatment, Crizotinib is not effective against brain metastases due to the presence of the blood-brain barrier which prevents toxins (including chemotherapy and targeted therapies) from entering the brain.’

Prof. Tony MOK led a multinational study from 2014 to 2016 on 303 patients from 29 countries with ALK-positive NSCLC.  Previously untreated, all patients were randomly divided into two groups; one group to receive Alectinib and the other Crizotinib over the same period.

Results revealed that Alectinib recorded a median of more than 25.7 months of progression-free survival, over double that of Crizotinib (10.4 months).  In addition, the probability of 1-year event-free survival was close to 70% with Alectinib, as opposed to 50% with Crizotinib.  It also had fewer side effects and was associated with greater reduction in lung cancer symptoms and greater improvement in quality of life.

The results are summarized in the table below:

New therapy especially beneficial in controlling and lowering the chance of brain metastases

The research team also proved that the novel targeted therapy was 70% more effective than the current standard of care in preventing tumours from spreading to the brain as it penetrates better into the brain and kills cancer cells.  

Professor MOK described the research findings as very significant and encouraging, ‘The study has proved that the second-line therapy outperforms the current standard one in  first-line treatment for ALK-positive lung cancer, meaning that the first-line use of Alectinib will be a new standard of care for these patients, with the belief that they can live longer and better.’

This remarkable research result by Professor MOK makes another important breakthrough in lung cancer treatment after his findings in 2014 proved that molecular targeted therapy is superior to standard first-line chemotherapy in ALK-positive lung cancer patients.  His  landmark study in 2009 also established the role of first-line treatment in patients with EGFR mutation, later suggesting a new treatment paradigm in 2016.  By understanding the molecular profile of lung cancer, physicians can customize the treatment for patients according to the genetic information of their tumor. This brings personalized medicine development of lung cancer into a new stage and enhances patients’ quality of life.