A personalised lung cancer pill launched today offers new hope to sufferers of a rare form of the disease.
The drug, crizotinib, targets a protein found in around five in 100 patients with the most common type of lung cancer.
Typically, these patients are much younger than average and do not appear to have a disease closely linked to smoking.
Marketed as Xalkori, the treatment was given an early licence by regulators after promising trial findings.
A Phase III study of 347 patients found that the drug more than doubled the time taken for treated tumours to start growing again or stop shrinking.
So-called "progression free survival" was increased from a mid-point of three months for patients on chemotherapy to 7.7 months.
Although survival time was not studied, researchers believe the drug has the potential to extend lives.
Crizotinib is the latest in a new generation of cancer drugs tailored to individuals with specific genetic make-ups.
It acts on a protein called ALK which blocks anti-cancer signalling pathways.
Patients who can benefit from crizotinib are identified by analysing biopsy tissue samples. They form a distinct subgroup among patients with non-small cell lung cancer (NSCLC), which accounts for 80-85% of lung cancer cases.
Dr Ekaterini Boleti, a member of the trial team from the Royal Free Hospital, London, said: "Lung cancer carries the most stigma of all cancer diseases and has a bad press. It's associated with patients not looking after themselves and smoking.
"But this is like a new entity within lung cancer. These patients tend to be younger than the average patient with lung cancer, and tend to be non-smokers or light smokers.
"It's not a cure drug, it's not a miracle drug, but it's a huge leap forward compared with what we had before.
"We see this as the beginning of a new era of cancer treatment. It's no longer relying on broad spectrum treatment - one bucket for treating everyone with the same thing. In the future, cancer treatment is going to be much more targeted and personalised."
The drug, made by Pfizer Ltd, will receive its full licence after all the trial data have been processed. It is yet to be assessed by the National Institute for health and Clinical Excellence (Nice) which looks at the cost-effectiveness of new NHS treatments.
Dr David Montgomery, medical director of Pfizer Oncology UK, said: "Today's news is a significant milestone for people with ALK-positive advanced NSCLC in the UK.
"Crizotinib is a new personalised treatment which offers the hope of better outcomes for people with this kind of lung cancer."