Lung cancer cell. Credit: LRI EM Unit
Patients with advanced non-small-cell lung cancer survived for 13.8 months on average when treated with the drug – called atezolizumab (Tecentriq) – compared to those treated with standard chemotherapy, who survived for 9.6 months on average.
Those on atezolizumab also experienced fewer side effects than those on chemotherapy, according to the phase 3 clinical trial led by scientists at the University Goettingen in Germany, which is published in The Lancet.
The drug blocks the PD-L1 molecule, which is often found in excess on the surface of cancer cells where it tells immune cells not to attack.
By blocking PD-L1, atezolizumab could be unveiling the cells to the immune system so they can be attacked and destroyed.
Professor Peter Johnson, Cancer Research UK’s chief clinician, said: “This is another great example of how research into the immune system can deliver powerful new treatments.
“This new era of cancer treatment provides hope for several cancer types, especially lung cancer and melanoma, that were previously really hard to treat effectively.”
The trial enrolled 1,225 patients who had no more treatment options available to them. And these latest results come from the first 850 patients who were treated.
Half were given atezolizumab and the other half were treated with docetaxel chemotherapy, the standard treatment for patients at this stage of their disease.
The study found that atezolizumab worked best for patients with the highest levels of the PD-L1 molecule on their cells. It more than doubled survival for these patients compared to chemotherapy (20.5 months compared with 8.9 months).
But survival was still higher compared to chemotherapy for those where tumour samples showed little to no levels of the molecule (12.6 compared with 8.9 months).
While the side effects of atezolizumab were more tolerable than the chemotherapy, 46 out of 609 patients (7.6%) did stop treatment because of side effects. This was compared to 108 out of 578 patients (18.7%) who stopped chemotherapy treatment due to side effects.
Dr Achim Rittmeyer, lead author, said atezolizumab reinvigorates patients’ immune systems against cancer and has shown significant results for increasing their survival.
Cancer Research UK’s Professor Johnson added: “It’s important that healthcare systems are able to adopt these advances as quickly as possible, to make sure patients benefit from this research.”
Atezolizumab is one of a handful of immunotherapy drugs – called checkpoint inhibitors – that target immune-regulating molecules on the surface of tumour cells or immune cells.
Two such drugs – called nivolumab (Opdivo) and pembrolizumab (Keytruda) – target PD-L1’s counterpart PD-1, which is found on the surface of immune cells. These drugs have also been shown to extend the lives of patients with advanced lung cancer, but not to the extent seen here with atezolizumab.
Commenting on the latest results, Professor Elisabeth Quoix, from Hôpitaux Universitaires de Strasbourg in France, said that studies like this suggest a time where chemotherapy is no longer the mainstay of treatment for these patients “is perhaps not so far away”.
But she added that further studies would be needed to work out the best way to use these drugs, and potentially in which combinations, to limit costs and get the best results for patients.
Rittmeyer, A., et al. (2016). Atezolizumab versus docetaxel in patients with previously treated non-small-cell lung cancer (OAK): a phase 3, open-label, multicentre randomised controlled trial. The Lancet. DOI: 10.1016/S0140-6736(16)32517-X