A new immunotherapy drug similar to the one denied to writer AA Gill can significantly extend the lives of lung cancer patients, trial results have shown.
Scientists compared the effectiveness of atezolizumab with standard chemotherapy in a group of 1,225 patients with advanced non-small-cell-lung cancer.
The drug, an antibody that leaves cancer cells vulnerable to immune attack, increased survival from an average 9.6 months to 13.8 months.
All of the patients had run out of treatment options, just as had AA Gill who died on Saturday aged 62 after revealing he had the "full English" of cancers.
The columnist and restaurant critic, a former smoker, had been diagnosed with lung cancer that had spread to his neck and pancreas.
Writing his last piece in the Sunday Times, he revealed that his oncologist had recommended immunotherapy but was not able to provide it on the NHS.
The suggested treatment, another antibody drug called nivolumab, would have cost £60,000 to £100,000 per year - about four times the cost of chemotherapy.
Both nivolumab and atezolizumab target the way some cancers shield themselves from the immune system. The cancers do this by hi-jacking a system that stops the body attacking itself, so immune cells "see" them as healthy tissue.
The new trial, published in The Lancet medical journal, showed that atezolizumab not only increased survival but caused fewer side effects than treatment with the chemotherapy drug docetaxel.
Lead researcher Dr Achim Rittmeyer, from Goettingen University in Germany, said: "Lung cancer is the most common cancer, affecting 1.8 million people each year worldwide. It is also the leading cause of cancer death worldwide and survival remains stubbornly low.
"Recently, important advances in the treatment of the disease have come from immunotherapies. Atezolizumab reinvigorates patients' immune systems against cancer, and our trial has shown that this has significant results for their survival."
The results were from an early analysis of the first 850 trial patients. Half were given atezolizumab and the other half docetaxel.
Patients whose cancers had the highest levels of a protein called PD-L1 responded best to the treatment. For these patients, atezolizumab doubled survival compared with chemotherapy, providing an extra 20.5 months of life on average.
PD-L1 (programmed cell death ligand 1) is a signalling protein on the surface of cancer cells that helps them hide from the immune system.
Atezolizumab and nivolumab attack the same cancer survival pathway but from different directions. Nivolumab blocks PD-L1's counterpart, the PD-1 protein which is on the surface of immune cells.
Commenting on the findings in The Lancet, Professor Elisabeth Quoix from the University Hospitals of Strasbourg, France, wrote: "After decades of disappointments with non-specific vaccines or more recently tumor associated antigen specific vaccines, immunotherapy with antibodies that target the PD-L1 and PD-1 pathway have emerged as a major therapeutic breakthrough.
"This treatment improves the prognosis of patients with non-small-cell lung cancer that cannot benefit from targeted therapies... The time in which chemotherapy will no more be the mainstay of treatment of metastatic non-small-cell lung cancer is perhaps not so far away."
Nivolumab is under review by the National Institute for Health and Care Excellence (Nice) which decides whether new drugs are cost effective enough to be available on the NHS in England.
NHS lung cancer patients in Scotland can already qualify for the drug.
In line with Nice's recommendation, nivolumab can be offered to NHS patients in England with melanoma skin cancer.
Atezolizumab is being looked at by Nice as a potential treatment for advanced bladder cancer.