A drug that could stop cancer cells repairing themselves has shown early signs of working. More than half of the 40 patients given berzosertib had the growth of their tumours halted.
Berzosertib was even more effective when given alongside chemotherapy, the trial run by the Institute of Cancer Research (ICR) and the Royal Marsden NHS Trust suggested.
The trial was designed to test the safety of the drug.
The drug is the first to be trialled of a new family of treatments, which block a protein involved in DNA repair.
Blocking this protein prevents cancers from mending damage to their cells.
It's part of a branch of treatment known as "precision medicine", which targets specific genes or genetic changes.
The study involved patients with very advanced tumours, for whom no other treatment had worked.
This was what is known as a "phase one" trial, which is only designed to test the safety of a treatment.
But the ICR said the researchers did find some early indications that berzosertib could stop tumours growing.