An immunotherapy drug can ward off head and neck cancers for twice as long as the standard treatment, in the biggest breakthrough in two decades.
Pembrolizumab stimulates the immune system to fight cancer, targeting a specific protein that enables the drug to wipe out cancer cells.
The drug kept cancer at bay in some patients for an average of five years, compared with 30 months when added to standard of care, a clinical trial found.
The results were presented at the annual meeting of the American Society of Clinical Oncology, the world’s largest cancer conference.
The trial, which involved more than 700 patients across 192 sites in 24 countries, was led by researchers at the Washington University School of Medicine. Dr Douglas Adkins, the study’s co-principal investigator and a professor of oncology, said the results were significant and notable because it was the first time such a drug had generated this effect.
Researchers around the world tested the drug in patients with newly diagnosed locally advanced head and neck cancers. Hundreds of thousands of patients are diagnosed with these cancers globally each year.
Of 714 patients in the trial, 363 received pembrolizumab followed by standard of care, and 351 received only the current standard of care – surgery to remove their tumour followed by radiotherapy with or without chemotherapy.
Standard of care has not changed for these patients in more than 20 years, and more than half are unlikely to survive for five years.
The immunotherapy worked particularly well for those with high levels of the immune marker PD-L1, but it increased dramatically the likelihood of patients with all types of head and neck cancers remaining well, without the disease progressing or returning.
Kevin Harrington, a professor of biological cancer therapies at the Institute ofCancerResearch, London, led a UK team involved in the trial, which was funded by the pharmaceutical company MSD.
“For patients with newly diagnosed, locally advanced head and neck cancer, treatments haven’t changed in over two decades,” he said. “Immunotherapy has been amazingly beneficial for patients with cancer that has come back or spread around the body but, until now, it hasn’t been as successful for those presenting for the first time with disease which has spread to nearby areas.
“This research shows that immunotherapy could change the world for these patients – it significantly decreases the chance of cancer spreading around the body, at which point it is incredibly difficult to treat.
“The results of this trial show that pembrolizumab dramatically increases the duration of disease remission for years longer than the current standard treatments. It works particularly well for those with high levels of immune markers, but it’s really exciting to see that the treatment improves outcomes for all head and neck cancer patients, regardless of these levels.”
Laura Marston, 45, from Derbyshire, joined the trial after she was diagnosed with stage 4 tongue cancer in 2019. “I am amazed I am still here six years later,” she said. “This treatment has given me the gift of life.”
Prof Kristian Helin, the chief executive of the Institute of Cancer Research, said: “Immunotherapy continues to deliver … To learn that patients with immunotherapy added to their treatment plan had, on average, double the length of time free from evidence of disease compared to those without it – with some patients still yet to see their cancer return – is wonderful.”