Immunotherapy breakthrough for prostate cancer

20 December, 2018

A clinical trial led by a team at the ICR and The Royal Marsden is the first to show the benefits of immunotherapy for some men with advanced, otherwise untreatable prostate cancer.

Researchers found that a subset of men who had exhausted all existing options for treatment survived much longer than expected when receiving the checkpoint inhibitor pembrolizumab - with many of them showing impressive remissions and prolonged disease control. The landmark international trial could lead to a subset of prostate cancers being treated with immunotherapy.

Of the 258 men with advanced prostate cancer who took part in the trial, 38 per cent were still alive a year after immunotherapy treatment and 11 per cent were still receiving the treatment a year after the trial began and had not seen their cancer grow.

The study which was funded by Merck Sharp & Dohme and presented at the American Society of Clinical Oncology's annual meeting in Chicago, also revealed vital clues for identifying the subset of patients who could especially benefit from immunotherapy.

Five per cent of men saw their tumours shrink or disappear after treatment, and researchers found this response was higher in those whose tumours had mutations in their DNA repair genes

Professor Johann de Bono, Director of the Drug Development Unit at the ICR and The Royal Marsden, said: 

"Immunotherapy has changed the way we treat many advanced cancers, but up to now, no one had demonstrated a benefit in men with prostate cancer. 

38%

of patients with advanced prostate cancer were still alive a year after immunotherapy treatment

We are planning a new clinical trial, specifically in men with prostate cancer whose tumours have mutations in their DNA repair genes, to see if immunotherapy can become part of their treatment.