Scientists, including one of the Indian-origin, have developed a new targeted treatment for ovarian cancer that shrinks tumours without causing any side effects. Researchers believe the drug, which mimics the action of the folic acid to enter cells, could hold huge promise for women with advanced ovarian cancer who have stopped responding to standard treatment. The drug kills cells by blocking a molecule called thymidylate synthase and causing irreparable DNA damage. “The results we have seen in this trial are very promising. It is rare to see such clear evidence of reproducible responses in these early stages of drug development,” said Udai Banerji, Deputy Director, Drug Development Unit at Institute of Cancer Research (ICR) in the UK.
“The beauty of this particular drug is that it is targeted to the cancer cell. This means there are fewer side- effects, making it a kinder treatment for ovarian cancer patients,” Banerji said. Ovarian cancer cells have an abnormally large number of receptors for folic acid, called alpha-folate receptors, they are particularly targeted by the treatment, while healthy cells are left alone, researchers said. They found that since the drug targets cancer cells specifically, it did not have side-effects often seen with traditional chemotherapy such as infections, diarrhoea, nerve damage and hair loss.
The team tested the drug, ONX-0801, in 15 women with ovarian cancer as part of a wider phase I clinical trial. Phase I trials are run in patients who have advanced cancer as a way of testing a drug’s safety, and it is highly unusual to see major clinical responses at this stage, researchers said. They found that the drug significantly shrunk tumours in seven of the 15 ovarian cancer patients – results the researchers described as ‘exciting’ and ‘very promising.