Less than 13 percent of patients with this cancer typically respond to chemotherapy and less than 14 percent respond to hormone therapy.
Results from the trial show that of the 24 patients involved, 46 percent saw their tumours shrink significantly.
In patients with a particular mutation, results proved to be even more successful.
Up to 64 percent of those who have KRAS-driven tumours saw them shrink after treatment.
The researchers said this suggested that tumour profiles could be used to identify which patients are most likely to benefit from the new treatment.
They also said those taking part in the trial –who were aged between 31 and 75 – lived for an average of 23 months before their cancer progressed.
Professor Kristian Helin, the chief executive of the ICR, said: “Overcoming cancer’s ability to evolve resistance to treatment is a huge challenge for cancer research.
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